Is Physiological Equivalent Temperature (PET) a superior screening tool for heat stress risk than Wet-Bulb Globe Temperature (WBGT) index? Eight years of data from the Gothenburg half marathon.

BACKGROUND: The Wet-Bulb Globe Temperature (WBGT) index is a common tool to screen for heat stress for sporting events. However, the index has a number of limitations. Rational indices, such as the physiological equivalent temperature (PET) and Universal Thermal Climate Index (UTCI), are potential alternatives. AIM: To identify the thermal index that best predicts ambulance-required assistances and collapses during a city half marathon. METHODS: Eight years (2010-2017) of meteorological and ambulance transport data, including medical records, from Gothenburg's half-marathon were used to analyse associations between WBGT, PET and UTCI and the rates of ambulance-required assistances and collapses. All associations were evaluated by Monte-Carlo simulations and leave-one-out-cross-validation. RESULTS: The PET index showed the strongest correlation with both the rate of ambulance-required assistances (R2=0.72, p=0.008) and collapses (R2=0.71, p=0.008), followed by the UTCI (R2=0.64, p=0.017; R2=0.64, p=0.017) whereas the WBGT index showed substantially poorer correlations (R2=0.56, p=0.031; R2=0.56, p=0.033). PET stages of stress, match the rates of collapses better that the WBGT flag colour warning. Compared with the PET, the WBGT underestimates heat stress, especially at high radiant heat load. The rate of collapses increases with increasing heat stress; large increase from the day before the race seems to have an impact of the rate of collapses. CONCLUSION: We contend that the PET is a better predictor of collapses during a half marathon than the WBGT. We call for further investigation of PET as a screening tool alongside WBGT.

Medical Emergencies During a Half Marathon Race - The Influence of Weather.

The aim was to analyze the influence of weather conditions on medical emergencies in a half-marathon, specifically by evaluating its relation to the number of non-finishers, ambulance-required assistances, and collapses in need of ambulance as well as looking at the location of such emergencies on the race course. Seven years of data from the world's largest half marathon were used. Meteorological data were obtained from a nearby weather station, and the Physiological Equivalent Temperature (PET) index was used as a measure of general weather conditions. Of the 315,919 race starters, 104 runners out of the 140 ambulance-required assistances needed ambulance services due to collapses. Maximum air temperature and PET significantly co-variated with ambulance-required assistances, collapses, and non-finishers (R2=0.65-0.92; p=0.001-0.03). When air temperatures vary between 15-29°C, an increase of 1°C results in an increase of 2.5 (0.008/1000) ambulance-required assistances, 2.5 (0.008/1000) collapses (needing ambulance services), and 107 (0.34/1000) non-finishers. The results also indicate that when the daily maximum PET varies between 18-35°C, an increase of 1°C PET results in an increase of 1.8 collapses (0.006/1000) needing ambulance services and 66 non-finishers (0.21/1000).

Can participants predict where ambulance-requiring cases occur at a half marathon?

OBJECTIVES: Despite endurance races leading to a substantial number of ambulance-requiring cases (ARC), little is known regarding where they occur, meaning that knowing where to place medical teams, ambulance pick-up points, etc, is difficult. This article investigates whether the location of ARCs can be identified by race participants. METHODS: Using the world's largest half marathon (Gothenburg half marathon) as a case, 237 runners were asked, post-race, to mark on a map which geographical point of the race was most exhausting. Using the level of agreement tests, these geographical points were then compared with the GPS positions of ARCs. RESULTS: According to the level of agreement tests, the most exhausting positions (MEP), as identified by participants, seem to be highly correlated to the location of ARCs. This study can also show that ambulance-requiring cases seem to be more prevalent towards the end of the race and in uphill sections. CONCLUSIONS: By asking participants where they found the race most exhausting it seems possible to identify high-risk places for an ARC. From a practical perspective, using this method could considerably increase the safety of competitors as well as improving the cost-effectiveness of safety interventions at endurance races. Further studies are needed to understand the specific risk factors of the high-risk areas as well as characteristics of collapsed runners.

A truncated analogue of CCL2 mediates anti-fibrotic effects on murine fibroblasts independently of CCR2.

The truncated [1+9-76] CCL2 analogue, also known as 7ND, has been described in numerous reports as an anti-inflammatory and anti-fibrotic agent in a wide spectrum of animal models, e.g. models of cardiovascular disease, graft versus host disease and bleomycin-induced pulmonary fibrosis. 7ND has been reported to function as a competitive inhibitor of CCL2 signaling via CCR2 in human in vitro systems. In contrast, the mechanistic basis of 7ND action in animal models has not been previously reported. Here we have studied how 7ND interacts with CCL2 and CCR2 of murine origin. Surprisingly, 7ND was shown to be a weak inhibitor of murine CCL2/CCR2 signaling and displaced murine CCL2 (JE) from the receptor with a K(i)>1 µM. Using surface plasmon resonance, we found that 7ND binds murine CCL2 with a K(d) of 670 nM, which may indicate that 7ND inhibits murine CCL2/CCR2 signaling by a dominant negative mechanism rather than by competitive binding to the CCR2 receptor. In addition we observed that sub-nanomolar levels of 7ND mediate anti-fibrotic effects in CCR2 negative fibroblasts cultured from fibrotic lung of bleomycin-induced mice. Basal levels of extracellular matrix proteins were reduced (collagen type 1 and fibronectin) as well as expression levels of α-smooth muscle actin and CCL2. Our conclusion from these data is that the previously reported effects of 7ND in murine disease models most probably are mediated via mechanisms independent of CCR2.

2-amino-1,3-thiazol-4(5H)-ones as potent and selective 11beta-hydroxysteroid dehydrogenase type 1 inhibitors: enzyme-ligand co-crystal structure and demonstration of pharmacodynamic effects in C57Bl/6 mice.

11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) has attracted considerable attention during the past few years as a potential target for the treatment of diseases associated with metabolic syndrome. In our ongoing work on 11beta-HSD1 inhibitors, a series of new 2-amino-1,3-thiazol-4(5 H)-ones were explored. By inserting various cycloalkylamines at the 2-position and alkyl groups or spirocycloalkyl groups at the 5-position of the thiazolone, several potent 11beta-HSD1 inhibitors were identified. An X-ray cocrystal structure of human 11beta-HSD1 with compound 6d (Ki=28 nM) revealed a large lipophilic pocket accessible by substitution off the 2-position of the thiazolone. To increase potency, analogues were prepared with larger lipophilic groups at this position. One of these compounds, the 3-noradamantyl analogue 8b, was a potent inhibitor of human 11beta-HSD1 (Ki=3 nM) and also inhibited 11beta-HSD1 activity in lean C57Bl/6 mice when evaluated in an ex vivo adipose and liver cortisone to cortisol conversion assay.