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To mitigate excessive rises in core temperature (>1 °C) in non-heat acclimatized workers, the American Conference of Governmental Industrial Hygienists (ACGIH) provides heat stress limits (Action Limit Values; ALV), defined by the wet-bulb globe temperature (WBGT) and a worker's metabolic rate. However, since these limits are based on data from men, their suitability for women remains unclear. We therefore assessed core temperature and heart rate in men (n = 19; body surface area-to-mass ratio: 250 (SD 17) cm2/kg) and women (n = 15; body surface area-to-mass ratio: 268 (SD 24) cm2/kg) aged 18-45 years during 180 min of walking at a moderate metabolic rate (200 W/m2) in WBGTs below (16 and 24 °C) and above (28 and 32 °C) ACGIH ALV. Sex did not significantly influence (i) rises in core temperature, irrespective of WBGT, (ii) the proportion of participants with rises in core temperature >1 °C in environments below ACGIH limits, and (iii) work duration before rises in core temperature exceeded 1 °C or volitional termination in environments above ACGIH limits. Although further studies are needed, these findings indicate that for the purpose of mitigating rises in core temperature exceeding recommended limits (>1 °C), ACGIH guidelines have comparable effectiveness in non-heat acclimatized men and women during moderate-intensity work. Novelty: Sex did not appreciably influence thermal strain nor the proportion of participants with core temperatures exceeding recommended limits. Sex did not significantly influence tolerance to uncompensable heat stress. Despite originating from data obtained in only men, current occupational heat stress guidance offered comparable effectiveness in men and women.

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This study evaluated if passive controlled hyperthermia heat acclimation modulates cognitive performance during passive heat stress. Eight healthy adults (25 ± 4 years) underwent 7 consecutive days of hot water immersion (core temperature ≥38.6 °C) and a 7-day time-control period. On days 1 and 7 of heat acclimation, participants performed a digital Stroop test at baseline, when core temperature reached 38.6 °C, and after 60 minutes at a core temperature ≥38.6 °C to evaluate reaction time during tasks targeting processing speed (reading and counting) and executive functions (inhibition and switching). On days 1 and 7 of the time-control intervention, participants performed the Stroop test with equivalent amounts of time separating each task as for heat acclimation. During day 1 of heat acclimation, reaction time was quicker during the reading (-44 ms [-71 to -17], P < 0.01) and counting (-39 ms [-76 to -2], P = 0.04) tasks when the rectal temperature reached 38.6 °C, but after a further 60 minutes of heat exposure, reaction time only remained quicker during the reading task (-56 ms [-83 to -29], P < 0.01). Changes in reaction time during heat exposure were unaffected by subsequent heat acclimation (interaction, all P ≥ 0.09). In conclusion, 7 days of heat acclimation does not modulate processing speed and executive functions during passive heat exposure. Novelty: Whether heat acclimation improves cognitive performance during heat exposure remains unclear. We tested the hypothesis that heat acclimation modulates reaction time during cognitive tasks performed at matched levels of thermal strain. Despite the classical signs of heat acclimation, reaction time during heat exposure is unaffected by heat acclimation.

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During uncompensable occupational heat stress, heat-mitigation controls are required to prevent core temperature exceeding recommended limits (≥38 °C). However, the initial stay time before employing controls remained unknown. We estimated these times for moderate-intensity work at 26, 28, 30, and 32 °C wet-bulb globe temperatures (WBGT) in 50 young (18-30 years) and older (50-70 years), non-heat acclimatized men. Initial stay time was 111 min at 26 °C WBGT and declined exponentially to 44 min at 32 °C WBGT. Novelty: We provide estimates of the moderate-intensity work duration before heat-mitigation is required in wet-bulb globe temperatures between 26-32 °C for young and older, non-heat acclimatized men.

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We examined if the change in heart rate variability during passive heat exposure is modified by hot water heat acclimation (HA). Sixteen healthy adults (28 ± 5 years, 5 females/11 males) underwent heat exposure in a water-perfused suit, before and after 7 days of HA (60 min at rectal temperature ≥38.6 °C). During passive heat exposure, heart rate, the standard deviation of NN intervals (SDNN), the square root of the mean squared differences of successive NN intervals (RMSSD), and the power in the high-frequency range (HF) were measured. No difference in heart rate (P = 0.22), SDNN (P = 0.87), RMSSD (P = 0.79), and HF (P = 0.23) was observed at baseline. The increase in HR (pre-HA, 43 ± 10; post-HA, 42 ± 9 bpm; P = 0.57) and the decrease of SDNN (pre-HA, -54.1 ± 41.0; post-HA, -52.2 ± 36.8 ms; P = 0.85), RMSSD (pre-HA, -70.8 ± 49.5; post-HA, -72.7 ± 50.4 ms; P = 0.91) and HF (pre-HA, -28.0% ± 14.5; post-HA, -23.2% ± 17.1%; P = 0.27) were not different between experimental visits at fixed increases in esophageal temperature. These results suggest that 7 consecutive days of hot water HA does not modify the change in heart rate variability indices during passive heat exposure. Novelty: It remains unclear if HA alters the change in heart rate variability that occurs during passive heat exposure. At matched levels of thermal strain, 7 consecutive days of hot water immersion did not modulate the change in indices of heart rate variability during passive heat exposure.

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Dopamine activity can modulate physical performance in the heat, but less is known about its effects on cognition during thermal stress. Twelves males completed a randomized, double-blinded protocol consisting of oral ingestion of 20 mg of methylphenidate (MPH) or placebo (lactose pill) during passive heating using a water-perfused suit (water temperature ∼49 °C). To identify the impact of peripheral versus central thermal strain, a cognitive test battery was completed at 4 different thermal states: baseline (BASE; 37.2 ± 0.6 °C core, 32.9 ± 0.7 °C skin), neutral core-hot skin (NC-HS; 37.2 ± 0.3 °C, 37.4 ± 0.3 °C), hyperthermic core-hot skin (HC-HS; 38.7 ± 0.4 °C, 38.7 ± 0.2 °C), and hyperthermic core-cooled skin (HC-CS; 38.5 ± 0.4 °C, 35.1 ± 0.8 °C). The cognitive test battery consisted of the 2-back task (i.e., working memory), set-shifting (i.e., executive function), Groton Maze Learning Task (i.e., executive function) and detection task (i.e., psychomotor processing). MPH led to significantly higher heart rates (∼5-15 b·min-1) at BASE, NC-HS, and HC-HS (all p < 0.05). There were no significant differences in the number of errors made on each task (all p < 0.05). Participants were significantly faster (p < 0.05) on the set-shifting task in the HC-HS timepoint, irrespective of drug condition (p > 0.05). In summary, we demonstrated that 20 mg of MPH did not significantly alter cognitive function during either normothermia or moderate hyperthermia. Novelty: Twenty milligrams of MPH did not significantly alter cognitive function during passive heat stress. MPH led to significant higher heart rates (∼5-15 b·min-1) in thermoneutral and during passive heat stress. Future studies are needed to determine the mechanisms of why MPH improves physical but not cognitive performance during heat stress.

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The effect of localised head and neck per-cooling on central and peripheral fatigue during high thermal strain was investigated. Fourteen participants cycled for 60 min at 50% peak oxygen uptake on 3 occasions: thermoneutral control (CON; 18 °C), hot (HOT; 35 °C), and HOT with head and neck cooling (HOTcooling). Maximal voluntary force (MVF) and central activation ratio (CAR) of the knee extensors were measured every 30 s during a sustained maximal voluntary contraction (MVC). Triplet peak force was measured following cycling, before and after the MVC. Rectal temperatures were higher in HOTcooling (39.2 ± 0.6 °C) and HOT (39.3 ± 0.5 °C) than CON (38.1 ± 0.3 °C; P < 0.05). Head and neck thermal sensation was similar in HOTcooling (4.2 ± 1.4) and CON (4.4 ± 0.9; P > 0.05) but lower than HOT (5.9 ± 1.5; P < 0.05). MVF and CAR were lower in HOT than CON throughout the MVC (P < 0.05). MVF and CAR were also lower in HOTcooling than CON at 5, 60, and 120 s, but similar at 30 and 90 s into the MVC (P > 0.05). Furthermore, they were greater in HOTcooling than HOT at 30 s, whilst triplet peak force was preserved in HOT after MVC. These results provide evidence that central fatigue following exercise in the heat is partially attenuated with head and neck cooling, which may be at the expense of greater peripheral fatigue. Novelty Central fatigue was greatest during hyperthermia. Head and neck cooling partially attenuated the greater central fatigue in the heat. Per-cooling led to more voluntary force production and more peripheral fatigue.

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INTRODUCTION: Cervical cancer is the twelfth most frequent cancer in women in France. Glassy cell carcinoma is a rare histological entity, rapidly aggressive, associated with a poor prognosis. CASE REPORT: A 30-year-old woman was admitted in an internal medicine department for polyarthralgia with high grade fever, evolving for 3 weeks. There was an inflammatory syndrome. The 18-FDG-PET-scan showed inflammatory lymph nodes as well as disseminated osteolytic lesions, and a primitive pelvic tumor. A 3cm tumor of the cervix was found during the gynaecologic examination. Histological analysis elicited a high-index mitotic carcinoma, glassy cell carcinoma type. Despite chemotherapy, the outcome was poor, with early death occurring after three months of follow-up. CONCLUSION: The glassy cell carcinoma of the cervix should be considered as an aetiology of bone metastases in young female patients.

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We examined if physical characteristics could be used to predict cooling time during cold water immersion (CWI, 2 °C) following exertional hyperthermia (rectal temperature ≥39.5 °C) in a physically heterogeneous group of men and women (n = 62). Lean body mass was the only significant predictor of cooling time following CWI (R2 = 0.137; P < 0.001); however, that prediction did not provide the precision (mean residual square error: 3.18 ± 2.28 min) required to act as a safe alternative to rectal temperature measurements.

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Colon adenocarcinoma is one of the most common cancers worldwide, and resistance to current therapeutic modalities is a serious drawback in its treatment. Auraptene is a natural coumarin with considerable anticancer effects. The goal of this study was to introduce a novel combinatorial approach for treatment against colon adenocarcinoma cells. To do so, HT29 cells were pretreated with nontoxic auraptene and then hyperthermia was induced. Afterwards, the viability of the cells was assessed, changes induced in the cell cycle were analyzed, and the expression patterns of candidate genes were studied. Results from the MTT assay demonstrated significant (p < 0.01) decreases in cell viability when 20 µg/mL auraptene was used for 72 h, heat shock was induced, and cells were allowed to recover for 24 h. Flow cytometry analysis also indicated considerable changes in the distribution of cells between the sub-G1/G1 and G2/M phases of cell cycle after the combinatorial treatment. Real-time RT-PCR studies revealed significant (p < 0.01) up-regulation of P21 in the cells pretreated with auraptene after heat shock, whereas no significant change was observed in HSP27 expression. Our findings not only indicate, for the first time, that the efficacy of hyperthermia was improved by auraptene pretreatment, but also suggest that this coumarin could be used in the future to achieve more effective therapeutic outcomes.

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This study investigated the effect of 5 days of controlled short-term heat acclimation (STHA) on the determinants of endurance performance and 5-km performance in runners, relative to the impairment afforded by moderate heat stress. A control group (CON), matched for total work and power output (2.7 W·kg-1), differentiated thermal and exercise contributions of STHA on exercise performance. Seventeen participants (10 STHA, 7 CON) completed graded exercise tests (GXTs) in cool (13 °C, 50% relative humidity (RH), pre-training) and hot conditions (32 °C, 60% RH, pre- and post-training), as well as 5-km time trials (TTs) in the heat, pre- and post-training. STHA reduced resting (p = 0.01) and exercising (p = 0.04) core temperature alongside a smaller change in thermal sensation (p = 0.04). Both groups improved the lactate threshold (LT, p = 0.021), lactate turnpoint (LTP, p = 0.005) and velocity at maximal oxygen consumption (vV̇O2max; p = 0.031) similarly. Statistical differences between training methods were observed in TT performance (STHA, -6.2(5.5)%; CON, -0.6(1.7)%, p = 0.029) and total running time during the GXT (STHA, +20.8(12.7)%; CON, +9.8(1.2)%, p = 0.006). There were large mean differences in change in maximal oxygen consumption between STHA +4.0(2.2) mL·kg-1·min-1 (7.3(4.0)%) and CON +1.9(3.7) mL·kg-1·min-1 (3.8(7.2)%). Running economy (RE) deteriorated following both training programmes (p = 0.008). Similarly, RE was impaired in the cool GXT, relative to the hot GXT (p = 0.004). STHA improved endurance running performance in comparison with work-matched normothermic training, despite equality of adaptation for typical determinants of performance (LT, LTP, vV̇O2max). Accordingly, these data highlight the ergogenic effect of STHA, potentially via greater improvements in maximal oxygen consumption and specific thermoregulatory and associated thermal perception adaptations absent in normothermic training.

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Varying temperature affects cardiac systolic and diastolic function and the left ventricular (LV) pressure-time curve (PTC) waveform that includes information about LV inotropism and lusitropism. Our proposed half-logistic (h-L) time constants obtained by fitting using h-L functions for four segmental phases (Phases I-IV) in the isovolumic LV PTC are more useful indices for estimating LV inotropism and lusitropism during contraction and relaxation periods than the mono-exponential (m-E) time constants at normal temperature. In this study, we investigated whether the superiority of the goodness of h-L fits remained even at hypothermia and hyperthermia. Phases I-IV in the isovolumic LV PTCs in eight excised, cross-circulated canine hearts at 33, 36, and 38 °C were analyzed using h-L and m-E functions and the least-squares method. The h-L and m-E time constants for Phases I-IV significantly shortened with increasing temperature. Curve fitting using h-L functions was significantly better than that using m-E functions for Phases I-IV at all temperatures. Therefore, the superiority of the goodness of h-L fit vs. m-E fit remained at all temperatures. As LV inotropic and lusitropic indices, temperature-dependent h-L time constants could be more useful than m-E time constants for Phases I-IV.

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Non-muscle-invasive bladder cancer (NMIBC) is characterised by a high risk of recurrence when performing only a transurethral resection of the bladder (TURB). Intravesical instillations are performed postoperatively to decrease the rate of recurrence. The standard agents currently used are Mitomycin-C (MMC) or bacillus Calmette-Guérin (BCG). In order to further enhance the efficacy of the adjuvant treatments and/or diminish their side effects, alternative treatments are studied. Intravesical MMC combined with hyperthermia could be an interesting alternative active treatment for intermediate- and possibly high-risk NMIBC, and has been investigated in the past years. Two methods for achieving hyperthermia are described and presently evaluated: heating the bladder wall by the mean of an intravesical microwave generator (Synergo®) and heating the MMC before it is instilled in the bladder (Combat BRS®). LEVEL OF EVIDENCE: 5.

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The fact that epilepsy consists in multiple heterogeneous syndromes with different etiologies and different symptoms is insufficiently taken into account in current animal models. This is in particular the case when modeling mesiotemporal lobe epilepsy (MTLE) for which clinical, electrophysiological, histological and pharmacological features have been well described in the clinic but only partially reproduced in most rodent models. In this review, we report the data of our recent survey of european neurologists with expertise in epilepsy. The answers of 82 of them (out of 258) indicated that seizures with mild behavioral signs, hippocampal sclerosis and focal discharges were the three most critical features to be considered when developing an animal model of MTLE. We then examined how these features are reproduced in three different types of animal models of MTLE depending on their induction: (i) generalized convulsive status epilepticus; (ii) hyperthermic seizures in immature animals and (iii) focal status epilepticus. Among them, only rodent models resulting from the induction of a focal status epilepticus appear to present most characteristics of human MTLE.

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Secondary localization to vagina had a severe prognosis, suggesting a disseminated metatastic disease. We report the case of prevalent vaginal metastasis of adenocarcinoma of the transverse colon. A 65 years old patient has consulted for vaginal mass. After delayed diagnosis, she presented with disseminated metastatic disease with peritoneal carcinomatosis. After neoadjuvant chemotherapy, the following treatment consisted of complete cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy and vaginal adjuvant radiotherapy. No recurrence occurred after one year. Vaginal metastasis of colon cancer are rare. The dark prognosis might justify a systematic gynecological examination of women presenting colorectal neoplasy.

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This case-report focused on the occurrence of a crisis of malignant hyperthermia on a young biker (21 y.o.) victim of a severe traffic accident. This observation gives some key points: the delayed occurrence of the crisis after 4 hours of surgery, the multi-factorial events that triggered the crisis; the choice to perform a quick diagnosis through gene analysis in comparison to the standard tests of caffeine on a muscular biopsy. These different points are discussed with a proposal of algorithm in the situation.

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