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Abstract Measurement of body core temperature (Tcore) is paramount to determining the thermoregulatory strain of athletes. However, standard measurement procedures of Tcore are not practical for extended use outside the laboratory environment. Therefore, determining the factors that predict Tcore during a self‐paced run is crucial for creating more effective strategies to minimize the heat‐induced impairment of endurance performance and reduce the occurrence of exertional heatstroke. The aim of this study was to identify the factors predicting Tcore values attained at the end of a 10 km time trial (end‐Tcore) under environmental heat stress. Initially, we extracted data obtained from 75 recordings of recreationally trained men and women. Next, we ran hierarchical multiple linear regression analyses to understand the predictive power of the following variables: wet‐bulb globe temperature, average running speed, initial Tcore, body mass, differences between Tcore and skin temperature (Tskin), sweat rate, maximal oxygen uptake, heart rate and change in body mass. Our data indicated that Tcore increased continuously during exercise, attaining 39.6 ± 0.5°C (mean ± SD) after 53.9 ± 7.5 min of treadmill running. This end‐Tcore value was primarily predicted by heart rate, sweat rate, differences between Tcore and Tskin, wet‐bulb globe temperature, initial Tcore, running speed and maximal oxygen uptake, in this order of importance (β power values corresponded to 0.462, −0.395, 0.393, 0.327, 0.277, 0.244 and 0.228, respectively). In conclusion, several factors predict Tcore in athletes subjected to self‐paced running under environmental heat stress. Moreover, considering the conditions investigated, heart rate and sweat rate, two practical (non‐invasive) variables, have the highest predictive power.

Background This study compared left ventricular (LV) characteristics between patients with type‐A and type‐B aortic dissection (AD) and evaluated the ability of LV remodeling phenotypes (hypertrophy, concentricity, or geometric patterns) to predict mortality in both AD types. Methods and Results We evaluated 236 patients with type A and 120 patients with type B who had echocardiograms within 60 days before or after AD diagnosis (median [25th, 75th percentiles] time difference between echocardiogram and AD diagnosis=1 [0, 6] days) from 3 centers. Patients were stratified according to LV phenotypes, and early (90‐day) and late (1‐year) mortality after AD diagnosis were assessed. In adjusted logistic regression analysis, patients with type A had higher and lower odds of concentric and eccentric hypertrophy (odds ratio [OR], 2.56; 95% CI, 1.50–4.36; P

Abstract Introduction The dynamic range of cerebrospinal fluid (CSF) amyloid β (Aβ1–42) measurement does not parallel to cognitive changes in Alzheimer's disease (AD) and cognitively normal (CN) subjects across different studies. Therefore, identifying novel proteins to characterize symptomatic AD samples is important. Methods Proteins were profiled using a multianalyte platform by Rules Based Medicine (MAP‐RBM). Due to underlying heterogeneity and unbalanced sample size, we combined subjects (344 AD and 325 CN) from three cohorts: Alzheimer's Disease Neuroimaging Initiative, Penn Center for Neurodegenerative Disease Research of the University of Pennsylvania, and Knight Alzheimer's Disease Research Center at Washington University in St. Louis. We focused on samples whose cognitive and amyloid status was consistent. We performed linear regression (accounted for age, gender, number of apolipoprotein E (APOE) e4 alleles, and cohort variable) to identify amyloid‐related proteins for symptomatic AD subjects in this largest ever CSF–based MAP‐RBM study. ANOVA and Tukey's test were used to evaluate if these proteins were related to cognitive impairment changes as measured by mini‐mental state examination (MMSE). Results Seven proteins were significantly associated with Aβ1–42 levels in the combined cohort (false discovery rate adjusted P < .05), of which lipoprotein a (Lp(a)), prolactin (PRL), resistin, and vascular endothelial growth factor (VEGF) have consistent direction of associations across every individual cohort. VEGF was strongly associated with MMSE scores, followed by pancreatic polypeptide and immunoglobulin A (IgA), suggesting they may be related to staging of AD. Discussion Lp(a), PRL, IgA, and tissue factor/thromboplastin have never been reported for AD diagnosis in previous individual CSF–based MAP‐RBM studies. Although some of our reported analytes are related to AD pathophysiology, other's roles in symptomatic AD samples worth further explorations.

Objective: To describe and compare the plantar pressures, temporal foot roll-over, and ground reaction forces (GRFs) between both limbs of subjects with unilateral transfemoral amputation and with those of able-bodied participants during walking. We also verify the relevance of a force plate and a pressure plate to discriminate changes in gait parameters of subjects with limb loss., Design: Cross-sectional study., Setting: Biomechanics laboratory., Subjects: A total of 14 subjects with unilateral transfemoral amputation and 21 able-bodied participants., Methods: We used a force plate and a pressure plate to assess biomechanical gait parameters while the participants were walking at their self-selected gait speed., Main Outcome Measurements: We measured plantar pressure peaks in 6 foot regions and the instant of their occurrence (temporal foot roll-over); and GRF peaks and impulses of anterior-posterior (braking and propulsive phases), medial-lateral, and vertical (load acceptance and thrust phases) components., Results: The thrust, braking, and propulsive peaks, and the braking and propulsive impulses, were statistically significantly lower in the amputated limb than in the sound limb (P < .05) and in able-bodied participants (P < .05). In the amputated limb, we observed higher pressure peaks in the lateral rearfoot and medial and lateral midfoot, and lower values in the forefoot regions compared to those in the other groups (P < .05). The temporal foot roll-over showed statistically significant differences among the groups (P < .05)., Conclusions: The plantar pressures, temporal foot roll-over, and GRFs in subjects with unilateral transfemoral amputation showed an asymmetric gait pattern, and different values were observed in both of their lower limbs as compared with those of able-bodied subjects during walking. The force plate and pressure plate were able to determine differences between participants in gait pattern, suggesting that both plantar pressure and GRF analyses are useful tools for gait assessment in individuals with unilateral transfemoral amputation. Because of the convenience of pressure plates, their use in the clinical context for prosthetic management appears relevant to guide the rehabilitation of subjects with lower limb amputation., (Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.)

Objective: To compare fiber-optic nasal endoscopy with Müller's maneuver (FNMM) against drug-induced sleep endoscopy (DISE) in diagnosing the presence of severe level-specific upper airway collapse in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS)., Study Design: Case series with chart review., Setting: Tertiary care academic center., Subjects and Methods: Medical records of all adult patients undergoing diagnostic DISE as part of their surgical evaluation were reviewed. Patients were included if they had undergone FNMM and had documented Friedman tongue position and tonsillar grade prior to DISE. Airway obstruction on both endoscopic procedures was described according to airway level and severity. Severe airway obstruction was defined as >75% collapse on endoscopy., Results: Fifty-three patients were included in this study. Fiber-optic nasal endoscopy with Müller's maneuver and DISE did not differ significantly regarding the presence of severe retropalatal airway collapse. There was a statistically significant difference in the incidence of severe retrolingual collapse identified via DISE (84.9% [45/53]) compared with FNMM (35.8% [19/53]; P < .0001). This discrepancy between FNMM and DISE findings was statistically significant in individuals with Friedman I and II tongue positions (FNMM = 16.7%, DISE = 88.9%, P < .0001) and individuals with Friedman III tongue position (FNMM = 31.8%, DISE = 81.8%, P = .002). Patients with Friedman IV showed no significant difference (P = .65) between FNMM (69.2%) and DISE (84.6%)., Conclusion: This study shows a significant difference between FNMM and DISE in the identification of severe retrolingual collapse. Since the effectiveness of surgical interventions depends largely on the accurate preoperative identification of the site of obstruction, further scrutiny of each diagnostic endoscopic technique is warranted.