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Female development includes significant morphological changes across the breast. Yet, whether differences in breast surface area (BrSA) modify breast skin stiffness and tactile sensitivity at rest and after exercise in the heat remain unclear. We investigated the relationship between BrSA and skin stiffness and tactile sensitivity in 20 young to middle-aged women (27 ± 8 years of age) of varying breast sizes (BrSA range: 147-502 cm 2 ) at rest and after a submaximal run in a warm climatic chamber (32 C ${\mathrm{C}}$  ±  0 . 6 C ; ${\mathrm{0}}{\mathrm{.6C;}}$ 53% ± 1.7% relative humidity). Skin stiffness above and below the nipple and tactile sensitivity from the nipple down were measured. Associations between BrSA and both skin stiffness and tactile sensitivity at rest were determined via correlation analyses. Effects of exercise and test site were assessed by a two-way ANOVA. Skin stiffness was positively correlated with BrSA 3 cm above the areola edge (r = 0.61, P = 0.005) and at the superior areola border (r = 0.54, P = 0.016), but not below the nipple (P > 0.05). The area 3 cm below the areola was also significantly stiffer than all other test sites (P < 0.043). Tactile sensitivity did not vary with BrSA (P > 0.09), but it varied across the breast (i.e., the area 3 cm below the areola was more sensitive than the inferior areola edge; P = 0.018). Skin stiffness and tactile sensitivity across the breast decreased after exercise by ∼37% (P < 0.001) and ∼45% (P = 0.008), respectively. These findings expand our fundamental understanding of the mechanosensory properties of the female breast, and they could help to inform sportswear innovation to better meet the support needs of women of different breast sizes at rest and following exercise., (© 2024 The Author(s). Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Female development includes significant morphological changes across the breast. Yet, whether differences in breast surface area (BrSA) modify sweat gland density and output remains unclear. The present study investigated the relationship between BrSA and sweat gland density and output in 22 young to middle-aged women (28 ± $\ \pm \ $ 10 years) of varying breast sizes (BrSA range: 147-561 cm 2 ) during a submaximal run in a warm environment (32  ± $ \pm \ $ 0.6°C; 53  ± $ \pm \ $ 1.7% relative humidity). Local sweat gland density and local sweat rate (LSR) above and below the nipple and at the bra triangle were measured. Expired gases were monitored for the estimation of evaporative requirements for heat balance (E req , in W/m 2 ). Associations between BrSA and (i) sweat gland density; (ii) LSR; and (iii) sweat output per gland for the breast sites were determined via correlation and regression analyses. Our results indicated that breast sweat gland density decreased linearly as BrSA increased (r = -0.76, P < 0.001), whereas sweat output per gland remained constant irrespective of BrSA (r = 0.29, P = 0.28). This resulted in LSR decreasing linearly as BrSA increased (r = -0.62, P = 0.01). Compared to the bra triangle, the breast had a 64% lower sweat gland density (P < 0.001), 83% lower LSR (P < 0.001) and 53% lower output per gland (P < 0.001). BrSA (R 2  = 0.33, P = 0.015) explained a greater proportion of variance in LSR than E req (in W/m 2 ) (R 2  = 0.07, P = 0.538). These novel findings extend the known relationship between body morphology and sweat gland density and LSR, to the female breast. This knowledge could innovate user-centred design of sports bras by accommodating breast size-specific needs for sweat management, skin wetness perception and comfort., (© 2024 The Author(s). Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Inclusive thermal comfort solutions should accommodate the need of clinical groups such as people with Multiple Sclerosis (pwMS), who experience abnormal thermal sensitivity. The aim of this study was to develop high-density body maps of temperature sensitivity in pwMS to inform the design of patient-centred personal comfort systems. Fourteen pwMS (6 M/8 F; 48.6 ± 10.0 y) and 13 healthy individuals (CTR; 5 M/8 F; 47.8 ± 10.4) underwent a quantitative sensory test in a thermoneutral environment, during which they rated their local thermal sensations arising from the application of warm (39°C) and cold (27°C) stimuli to 115 bilateral body sites across the face, torso, upper and lower limbs. We used a z-transformation to create maps of hypo- and hyper-sensitivity for each individual MS participant using normative CTR data. We found that 50% of pwMS (N = 7/14) presented a loss of cold sensitivity over the upper limb, and a loss of warm sensitivity over the feet. Furthermore, 36% of pwMS (N = 5) presented warm hyper-sensitivity over the upper limb. Finally, cold sensitivity loss and warm sensitivity gain were more evenly distributed and affected a greater proportion of skin sites in MS (i.e. cold hypo-sensitivity = 44% of tested sites; warm hyper-sensitivity = 14%) than warm sensitivity loss (i.e. 10%), which was more focused on sites such as the feet. Our findings highlight the need to consider "thermosensory corrective power" when designing personal comfort systems, to accommodate either thermosensory loss or gain in pwMS. Our approach to clinical body mapping may support this process and help meeting the unique thermal needs of vulnerable individuals., Competing Interests: Declaration of competing interest The authors report no conflict of interest., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Cytokine-induced β-cell apoptosis is a major pathogenic mechanism in type 1 diabetes (T1D). Despite significant advances in understanding its underlying mechanisms, few drugs have been translated to protect β-cells in T1D. Epigenetic modulators such as bromodomain-containing BET (bromo- and extra-terminal) proteins are important regulators of immune responses. Pre-clinical studies have demonstrated a protective effect of BET inhibitors in an NOD (non-obese diabetes) mouse model of T1D. However, the effect of BET protein inhibition on β-cell function in response to cytokines is unknown. Here, we demonstrate that I-BET, a BET protein inhibitor, protected β-cells from cytokine-induced dysfunction and death. In vivo administration of I-BET to mice exposed to low-dose STZ (streptozotocin), a model of T1D, significantly reduced β-cell apoptosis, suggesting a cytoprotective function. Mechanistically, I-BET treatment inhibited cytokine-induced NF-kB signaling and enhanced FOXO1-mediated anti-oxidant response in β-cells. RNA-Seq analysis revealed that I-BET treatment also suppressed pathways involved in apoptosis while maintaining the expression of genes critical for β-cell function, such as Pdx1 and Ins1. Taken together, this study demonstrates that I-BET is effective in protecting β-cells from cytokine-induced dysfunction and apoptosis, and targeting BET proteins could have potential therapeutic value in preserving β-cell functional mass in T1D.

July 2023 has been confirmed as Earth's hottest month on record, and it was characterized by extraordinary heatwaves across southern Europe. Field data collected under real heatwave periods could add important evidence to understand human adaptability to extreme heat. However, field studies on human physiological responses to heatwave periods remain limited. We performed field thermo-physiological measurements in a healthy 37-years male undergoing resting and physical activity in an outdoor environment in the capital of Sicily, Palermo, during (July 21; highest level of local heat-health alert) and following (August 10; lowest level of local heat-health alert) the peak of Sicily's July 2023 heatwave. Results indicated that ~40 min of outdoor walking and light running in 33.8°C Wet Bulb Globe Temperature (WBGT) conditions (July 21) resulted in significant physiological stress (i.e., peak heart rate: 209 bpm; core temperature: 39.13°C; mean skin temperature: 37.2°C; whole-body sweat losses: 1.7 kg). Importantly, significant physiological stress was also observed during less severe heat conditions (August 10; WBGT: 29.1°C; peak heart rate: 190 bpm; core temperature: 38.48°C; whole-body sweat losses: 2 kg). These observations highlight the physiological strain that current heatwave conditions pose on healthy young individuals. This ecologically-valid empirical evidence could inform more accurate heat-health planning., (© 2024 The Author(s). Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

This study protocol aims to investigate how localised cooling influences the skin's microvascular, inflammatory, structural, and perceptual tolerance to sustained mechanical loading at the sacrum, evaluating factors such as morphology, physiology, and perceptual responses. The protocol will be tested on individuals of different age, sex, skin tone and clinical status, using a repeated-measure design with three participants cohorts: i) young healthy (n = 35); ii) older healthy (n = 35); iii) spinal cord injured (SCI, n = 35). Participants will complete three testing sessions during which their sacrum will be mechanically loaded (60 mmHg; 45 min) and unloaded (20 min) with a custom-built thermal probe, causing pressure-induced ischemia and post-occlusive reactive hyperaemia. Testing sessions will differ by the probe's temperature, which will be set to either 38°C (no cooling), 24°C (mild cooling), or 16°C (strong cooling). We will measure skin blood flow (via Laser Doppler Flowmetry; 40 Hz); pro- and anti-inflammatory biomarkers in skin sebum (Sebutape); structural skin properties (Optical Coherence Tomography); and ratings of thermal sensation, comfort, and acceptance (Likert Scales); throughout the loading and unloading phases. Changes in post-occlusive reactive hyperaemia will be considered as the primary outcome and data will be analysed for the independent and interactive effects of stimuli's temperature and of participant group on within- and between-subject mean differences (and 95% Confidence Intervals) in peak hyperaemia, by means of a 2-way mixed model ANOVA (or Friedman). Regression models will also be developed to assess the relationship between absolute cooling temperatures and peak hyperaemia. Secondary outcomes will be within- and between-subject mean changes in biomarkers' expression, skin structural and perceptual responses. This analysis will help identifying physiological and perceptual thresholds for the protective effects of cooling from mechanically induced damage underlying the development of pressure ulcers in individuals varying in age and clinical status., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Gordon et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Women are a group of individuals that undergo unique anatomical, physiological and hormonal changes across the lifespan. For example, consider the impact of the menstrual cycle, pregnancy and menopause, all of which are accompanied by both short- and long-term effects on female body morphology (e.g., changes in breast size) and temperature regulation, heat tolerance, thermal sensitivity and comfort. However, empirical evidence on how skin thermal and wetness sensitivity might change across the lifespan of women, and the implications that this has for female-specific thermal behaviours, continues to be lacking. This paper is based on a symposium presentation given at Physiology 2023 in Harrogate, UK. It aims to review new evidence on anatomical and physiological mechanisms underpinning differences in skin thermal and wetness sensitivity amongst women varying in breast size and age, in addition to their role in driving female thermal behaviours. It is hoped that this brief overview will stimulate the development of testable hypotheses to increase our understanding of the behavioural thermal physiology of women across the lifespan and at a time of climate change., (© 2024 The Authors. Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Objective: Despite expanded guidelines, adolescent gonorrhea and chlamydia (GC/CT) screening rates remain low due to multiple psychosocial barriers and biases. This intervention aimed to improve screening and diagnosis rates at adolescent well visits by establishing a streamlined universal screening protocol for all patients ages 13-18 years old., Methods: A universal sexually transmitted infection (STI) screening approach was introduced at an urban clinic affiliated with an academic medical center near Philadelphia, Pennsylvania (PA) in September 2018 for all adolescent well-visits. GC/CT screening and diagnosis rates were compared two years prior to and two years after implementation, deemed the baseline and intervention groups, respectively., Results: In total, 1,168 encounters were included for analysis. The patient cohort consisted of 47% females, with an average age of 15, and were predominantly publicly insured (79%). STI screening rates increased significantly from 16.7% (89/534) to 83.6% (530/634) of adolescents with implementation of the universal screening protocol. Furthermore, there was a 1.6-fold increase in total positive cases detected after implementation of ok universal screening., Conclusion: This study demonstrates improved adolescent GC/CT capture rates by establishing a universal screening protocol and highlights a streamlined means of implementation in virtually any pediatric clinic. Limitations include sample size, as this is a single academic practice, as well as any issues with lab collection and results reporting., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Background: Cervical collars restrict cervical spine movement to minimise the risk of spinal cord injury. Collars apply mechanical loading to the skin putting it at risk of skin damage. Indeed, cervical collar-related pressure ulcers are unacceptably prevalent, especially at the occiput, mandibles, and chin. Collar design and fit are often key considerations for prevention., Methods: This comprehensive study evaluated four commercial prehospital and acute care cervical collars. Pressure, microclimate, transepidermal water loss and skin hydration were measured at the interface between the device and the skin. Range of motion restriction was measured to evaluate effective immobilisation. Head, neck, and shoulder morphology was evaluated using three-dimensional scans., Findings: The occiput experienced significantly higher interface pressures than the chin and mandibles for most collar designs. Interface pressure at the occiput was significantly higher for the Stiffneck extrication collar compared to the other collar designs. The Stiffneck collar also provided the most movement restriction, though not significantly more than other designs. Relative humidity at the device skin interface was significantly higher for the Stiffneck and Philadelphia collars corresponding to closed cell foam padding, in contrast to the open cell foams lined with permeable fabric used in the other collars. Collar discomfort correlated with both occipital pressure and skin humidity., Interpretation: The occiput is at increased risk of cervical collar-related pressure ulcers during supine immobilisation, especially for Stiffneck extrication collars. Lined open-cell foams could be used to minimise skin humidity and increase comfort., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Women continue to be under-represented in thermoregulatory research despite their undergoing unique physiological changes across the lifespan. This study investigated the biophysical, thermo-physiological, and perceptual determinants of cool-seeking behaviour during exercise in younger and older women. Eleven younger (25 ± 5 years; 1.7 ± 0.1 m; 63.1 ± 5.2 kg) and 11 older women (53 ± 6 years; 1.7 ± 0.1 m; 65.4 ± 13.9 kg) performed a 40-min incremental cycling test in a thermoneutral environment (22 ± 1.7°C; 36 ± 4% relative humidity). Throughout the test, participants freely adjusted the temperature of a cooling probe applied to their wrists to offset their thermal discomfort. We continuously recorded the probe-wrist interface temperature to quantify participants' cool-seeking behaviour. We also measured changes in participants' rate of metabolic heat production, core and mean skin temperatures, and skin wetness. Finally, we body-mapped participants' skin heat, cold and wetness sensitivity. Our results indicated that: (1) older and younger women exhibited similar onset and magnitude of cool-seeking behaviour, despite older women presented reduced autonomic heat-dissipation responses (i.e., whole-body sweat losses); (2) older women's thermal behaviour was less determined by changes in core temperature (this being a key driver in younger women), and more by changes in multiple thermo-physiological and biophysical parameters (i.e., physical skin wetness, temperature and heat production); (3) older women did not present lower regional skin thermal and wetness sensitivity than younger women. We conclude that predictions of female cool-seeking behaviours based on thermo-physiological variables should consider the effects of ageing. These findings are relevant for the design of wearable cooling systems and sports garments that meet the thermal needs of women across the lifespan., (© 2023 The Authors. Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

The purpose of this study was to characterize the perception of heat loss, comfort, and wetness in recreational surfers wearing wetsuits, to compare these data with changes in skin temperature reported in prior studies, and to examine the impact of wetsuit thickness, zipper location, and accessory use on thermal sensation and comfort. Following their surf session, nine-hundred and three male (n = 735) and female (n = 168) recreational surfers responded to a series of questions regarding thermal comfort/sensation, wetsuit characteristics, and surfing history. Average whole body thermal sensation rating was 0.8 ± 3.6 on a scale of -10 to +10 and average whole body thermal comfort rating was 1.5 ± 1.2, midway between "just comfortable" and "comfortable." Overall, surfers felt coldest in their feet, hands, and head. Under their wetsuits, surfers felt the coldest, wettest, and least comfortable in their chest, lower legs, lower arms, and upper back. Wetsuit accessory use had the greatest impact on regions identified as coldest, least comfortable, and wettest. These data suggest that wetsuit design should focus on optimizing water access points and improving accessories for the feet, hands, and head., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: The purpose of this study was to evaluate temporal changes in skin responses following exposure to moisture alone or moisture in combination with mechanical loading., Design: Comparison cohort with a repeated-measures design., Subjects and Settings: The sample comprised 12 healthy volunteers. Participants were purposely sampled from 2 different age groups; half were 32 to 39 years old and half were 50 to 62 years old. Participants identified as White, Black, or mixed; 83% (n = 10) identified as White; 8 (67%) were female., Methods: Four sites at the sacrum were challenged with the application of specimens taken from 2 absorbent products; the pad specimens were applied dry or saturated with synthetic urine (SU; pH = 8); a further site from the sacral skin was also selected and used as a control. Skin assessments were performed at different points in time: (1) 60 minutes after exposure to dry or SU-saturated pad specimens; (2) 60 minutes after exposure to pads and mechanical loading (application of pressure in the form of 45°C high sitting); and (3) 30 minutes after removal of all pads (recovery period). Outcome measures were transepidermal water loss (TEWL), stratum corneum (SC) hydration, erythema, pH, and skin inflammatory biomarkers measured at each of the time points described earlier., Results: The control site and those exposed to dry pads showed minimal time-dependent changes irrespective of the parameter investigated. In contrast, significant increases in TEWL (P = .0000007) and SC hydration responses (P = .0000007) were detected at the sites under absorbent pad specimens after saturation with SU (exposure to moisture). In some participants, TEWL and SC hydration parameters were significantly higher during pressure application. Skin pH remained in the mildly acidic range throughout the test session, and no consistent trends were observed with erythema. Skin inflammatory biomarkers also exhibited considerable variability across participants; none changed significantly over time. Significant differences (P = .02) were also detected following the exposure of moisture in combination with pressure., Conclusion: We evaluated an array of parameters to identify changes following skin exposure to 2 absorbent pads in the presence and absence of SU and mechanical loading. Analysis revealed changes in skin barrier properties in the presence of moisture and/or pressure. This observation suggests a need for frequent pad changing as well as periods of skin off-loading to protect the skin health of individuals with incontinence., Competing Interests: Disclosures: Shabira Abbas is a senior scientist at Essity AB. The other authors have no conflicts of interest., (Copyright © 2023 by the Wound, Ostomy and Continence Nurses Society.)

In acute care facilities, the detection of pressure ulcers (PUs) relies on visual and manual examination of the patient's skin, which has been reported to be inconsistent and may lead to misdiagnosis. In skin and wound research, various biophysical parameters have been extensively employed to monitor changes in skin health. Nonetheless, the transition of these measures into care settings as part of a routine clinical assessment has been limited. This study was designed to examine the spatial and temporal changes in skin biophysical parameters over the site of a category I PU, in a cohort of hospitalised patients. Thirty patients, each presenting with a category I PU, were enrolled in the study. Skin integrity was assessed at the PU-compromised site and two adjacent areas (5 and 10 cm away). Data was collected over three sessions to examine both temporal differences and longitudinal changes. Skin integrity was assessed using two biophysical parameters, namely, transepidermal water loss (TEWL) and stratum corneum (SC) hydration. In addition, the influence of intrinsic factors, namely, incontinence and mobility status, on the parameters was evaluated. TEWL values at the sites compromised by PU were statistically significantly greater (P < .001) than corresponding values at the adjacent control sites at 5 and 10 cm, which were consistent with a normative range (<20 g/h/m 2 ). By contrast, SC hydration values did not reveal clear distinctions between the three sites, with high inter-patient variation detected at the sites. Nevertheless, individual profiles were consistent across the three sessions, and the PU site was observed to be either abnormally dry or overhydrated in different individuals. No consistent temporal trend in either parameter was evident. However, intrinsic factors were shown to influence the parameters, with females, bedridden and incontinent patients presenting significantly higher TEWL and SC hydration values (P < .05). TEWL was able to identify differences in skin responses at skin sites compromised with a category I PU when compared to healthy adjacent skin sites. Accordingly, this parameter could be included in the clinical assessment for the identification of PU risk. Further studies are required to elucidate the role of hydration and skin barrier function in the development of PUs and their ability to monitor temporal changes in skin integrity., (© 2023 The Authors. International Wound Journal published by Medicalhelplines.com Inc and John Wiley & Sons Ltd.)

Preliminary human studies show that reduced skin temperature minimises the risk of mechanically induced skin damage. However, the mechanisms by which cooling enhances skin tolerance to pressure and shear remain poorly understood. We hypothesized that skin cooling below thermo-neutral conditions will decrease kinetic friction at the skin-material interface. To test our hypothesis, we measured the friction coefficient of a thermally pre-conditioned index finger pad sliding at a normal load (5N) across a plate maintained at three different temperatures (38, 24, and 16 °C) in 8 healthy young adults (29±5y). To quantify the temperature distribution of the skin tissue, we used 3D surface scanning and Optical Coherence Tomography to develop an anatomically representative thermal model of the finger. Our group-level data indicated that the sliding finger with thermally affected tissues (up to 8 mm depth) experienced significantly lower frictional forces (p<0.01) at plate temperatures of 16 °C (i.e. 32% decrease) and 24 °C (i.e. 13% decrease) than at 38 °C, respectively. This phenomenon occurred consistently across participants (i.e. N = 6/8, 75%) and without large changes in skin hydration during sliding. Our complementary experimental and theoretical results provide new insights into thermal modulation of skin friction that can be employed for developing thermal technologies to maintain skin integrity under mechanical loading and shearing., Competing Interests: Declaration of competing interest We declare we have no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

A multitude of sensory modalities are involved in humans' experience of wetness, yet we know little of the integratory role of vision. Therefore, the aim was to quantify the effect of physical stain volume, chroma and size on wetness perception, and to compare wetness perception under different sensory conditions, including visuotactile and visual only interactions. Eighteen participants visually observed and/or used their index fingerpad to dynamically interact with stimuli varying in physical wetness (0, 2.16 × 10 -4 or 3.45 × 10 -4  ml mm -2 ), stain chroma (clear, light, dark) and stain size (1150 or 5000 mm 2 ). After interaction participants rated wetness perception using a visual analogue scale (very dry to very wet). In visual only conditions participants were able to differentiate between dry and wet stimuli, and could also discriminate between different magnitudes of wetness with the addition of tactile cues. In both visual only and visuotactile conditions greater stain chroma resulted in increased wetness perception. Stain size did not have a significant effect in either condition. These results show that visual cues influence wetness perception ( R 2  = 0.29), but indicate that visual dominance does not apply in these sensory integrations. Findings are relevant for the design of products with wetness management properties.

Pressure Ulcers (PU) are a major burden for affected patients and healthcare providers. Current detection methods involve visual assessments of the skin by healthcare professionals. This has been shown to be subjective and unreliable, with challenges associated with identifying erythema in darker colour skin. Although there exists a number of promising non-invasive biophysical techniques such as ultrasound, capacitance measurements, and thermography, the present study focuses on directly measuring the changes in the inflammatory status of the skin and underlying tissues. Therefore, in this study, we aim to analyse inflammatory cytokines collected through non-invasive sampling techniques to detect early signs of skin damage. Thirty hospitalised patients presenting with Stage I PU were recruited to evaluate the inflammatory response of skin at the site of damage and an adjacent healthy control site. Sebutapes were collected over three sessions to investigate the temporal changes in the inflammatory response. The panel of cytokines investigated included high-abundance cytokines, namely, IL-1α and IL-1RA, and low abundance cytokines; IL-6, IL-8, TNF-α, INF-γ, IL-33, IL-1β and G-CSF. Spatial and temporal differences between sites were assessed and thresholds were used to determine the sensitivity and specificity of each biomarker. The results suggest significant (P < .05) spatial changes in the inflammatory response, with upregulation of IL-1α, IL-8, and G-CSF as well as down-regulation of IL-1RA over the Stage I PU compared with the adjacent control site. There were no significant temporal differences between the three sessions. Selected cytokines, namely, IL-1α, IL-1RA, IL-8, G-CSF, and the ratio IL-1α/IL-1RA offered clear delineation in the classification of healthy and Stage-I PU skin sites, with receiver operating characteristic curves demonstrating high sensitivity and specificity. There were limited influences of intrinsic and extrinsic factors on the biomarker response. Inflammatory markers provided a high level of discrimination between the sites presenting with Stage I PU and an adjacent healthy skin site, in a cohort of elderly inpatients. Indeed, the ratio of IL-1α to IL-1RA provided the highest sensitivity and specificity, indicative that inflammatory homeostasis is affected at the PU site. There was a marginal influence of intrinsic and extrinsic factors, demonstrating the localised effects of the inflammation. Further studies are required to investigate the potential of inflammatory cytokines incorporated within Point of Care technologies, to support routine clinical use., (© 2023 The Authors. International Wound Journal published by Medicalhelplines.com Inc and John Wiley & Sons Ltd.)

Commercial pressure monitoring systems have been developed to assess conditions at the interface between mattress/cushions of individuals at risk of developing pressure ulcers. Recently, they have been used as a surrogate for prolonged posture and mobility monitoring. However, these systems typically consist of high-resolution sensing arrays, sampling data at more than 1 Hz. This inevitably results in large volumes of data, much of which may be redundant. Our study aimed at evaluating the optimal number of sensors and acquisition frequency that accurately predict posture and mobility during lying. A continuous pressure monitor (ForeSitePT, Xsensor, Calgary, Canada), with 5664 sensors sampling at 1 Hz, was used to assess the interface pressures of healthy volunteers who performed lying postures on two different mattresses (foam and air designs). These data were down sampled in the spatial and temporal domains. For each configuration, pressure parameters were estimated and the area under the Receiver Operating Characteristic curve (AUC) was used to determine their ability in discriminating postural change events. Convolutional Neural Network (CNN) was employed to predict static postures. There was a non-linear decline in AUC values for both spatial and temporal down sampling. Results showed a reduction of the AUC for acquisition frequencies lower than 0.3 Hz. For some parameters, e.g., pressure gradient, the lower the sensors number the higher the AUC. Posture prediction showed a similar accuracy of 63-71% and 84-87% when compared to the commercial configuration, on the foam and air mattress, respectively. This study revealed that accurate detection of posture and mobility events can be achieved with a relatively low number of sensors and sampling frequency.

The negative effects of thermal stress on Multiple Sclerosis (MS)' symptoms have long been known. However, the underlying mechanisms of MS heat and cold intolerance remain unclear. The aim of this study was to evaluate body temperatures, thermal comfort, and neuropsychological responses to air temperatures between 12 and 39 °C in people with MS compared to healthy controls (CTR). Twelve MS (5 males/7 females; age: 48.3 ± 10.8 years; EDSS range: 1-7) and 11 CTR participants (4 males /7 females; age: 47.5 ± 11.3 years) underwent two 50-min trials in a climatic chamber. Air temperature was ramped from 24 °C to either 39 °C (HEAT) or 12 °C (COLD) and we continuously monitored participants' mean skin (T sk ) and rectal temperatures (T rec ), heart rate and mean arterial pressure. We recorded participants' self-reported thermal sensation and comfort, mental and physical fatigue, and we assessed their cognitive performance (information processing). Changes in mean T sk and T rec did not differ between MS and CTR neither during HEAT nor COLD. However, at the end of the HEAT trial, 83% of MS participants and 36% of CTR participants reported being "uncomfortable". Furthermore, self-reports of mental and physical fatigue increased significantly in MS but not CTR (p < 0.05), during both HEAT and COLD. Information processing was lower in MS vs. CTR (p < 0.05); yet this cognitive impairment was not exacerbated by HEAT nor COLD (p > 0.05). Our findings indicate that neuropsychological factors (i.e. discomfort and fatigue) could contribute to MS heat and cold intolerance in the absence of deficits in the control of body temperature., Competing Interests: Declaration of Competing Interest The authors report no conflict of interest., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Differences in skin thermal sensitivity have been extensively mapped across areas of the human body, including the torso, limbs, and extremities. Yet, there are parts of the female body, such as the breast and the pelvis for which we have limited thermal sensitivity data. The aim of this study was to map cutaneous warm and cold sensitivity across skin areas of the breast and pelvis that are commonly covered by female underwear. Twelve young females (21.9 ± 3.2 years) reported on a 200 mm visual analogue scale the perceived magnitude of local thermal sensations arising from short-duration (10 s) static application of a cold [5 °C below local skin temperature (T sk )] or warm (5 °C above local T sk ) thermal probe (25 cm 2 ) in seventeen locations over the breast and pelvis regions. The data revealed that thermal sensitivity to the warm probe, but not the cold probe, varied by up to 25% across the breast [mean difference between lowest and highest sensitivity location was 51 mm (95% CI:14, 89; p < 0.001)] and up to 23% across the pelvis [mean difference between lowest and highest sensitivity location: 46 mm (95% CI:9, 84; p = 0.001)]. The regional differences in baseline T sk did not account for variance in warm thermal sensitivity. Inter-individual variability in thermal sensitivity ranged between 24 and 101% depending on skin location. We conclude that the skin across the female breast and pelvis presents a heterogenous distribution of warm, but not cold, thermal sensitivity. These findings may inform the design of more comfortable clothing that are mapped to the thermal needs of the female body., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Skin wetness sensing is important for thermal stress resilience. Individuals with multiple sclerosis (MS) present greater vulnerability to thermal stress; yet, it is unclear whether they present wetness-sensing abnormalities. We investigated the effects of MS on wetness sensing and their modulation with changes in mean skin temperature (T sk ). Twelve participants with MS [5 males (M)/7 females (F); 48.3 ± 10.8 yr; Expanded Disability Status Scale (EDSS) range: 1-7] and 11 healthy controls (4 M/7 F; 47.5 ± 11.3 yr) undertook three trials, during which they performed a quantitative sensory test with either a thermoneutral (30.9°C), warm (34.8°C), or cold (26.5°C) mean T sk . Participants reported on visual analog scales local wetness perceptions arising from the static and dynamic application of a cold-, neutral-, and warm-wet probe (1.32 cm 2 ; water content: 0.8 mL), to the index finger pad, forearm, and forehead. Data were analyzed for the group-level effect of MS, as well as for its individual variability. Our results indicated that MS did not alter skin wetness sensitivity at a group level, across the skin sites and temperature tested, neither under normothermia nor under conditions of shifted thermal state. However, when taking an individualized approach to profiling wetness-sensing abnormalities in MS, we found that 3 of the 12 participants with MS (i.e., 25% of the sample) presented a reduced wetness sensitivity on multiple skin sites and to different wet stimuli (i.e., cold, neutral, and warm wet). We conclude that some individuals with MS may possess reduced wetness sensitivity; however, this sensory symptom may vary greatly at an individual level. Larger-scale studies are warranted to characterize the mechanisms underlying such individual variability.

Background: The negative effects of heat and cold on Multiple Sclerosis (MS) have been known for ∼100 years. Yet, we lack patient-centred investigations on temperature sensitivity in persons with MS (pwMS)., Objectives: To evaluate triggers, symptoms, and thermal resilience practices of temperature sensitivity pwMS via a dedicated survey., Methods: 757 pwMS completed an online survey assessing the subjective experience of temperature sensitivity. We performed descriptive statistics and regression analyses to evaluate association between individual factors and susceptibility/resilience to thermal stress., Results: Temperature sensitivity varied significantly in pwMS, with 58% of participants being heat sensitive only; 29% heat and cold sensitive; and 13% cold sensitive only (p<0.001). Yet, all pwMS: i) experienced hot and cold days as primary triggers; ii) reported fatigue as the most common worsening symptom, impacting walking and concentration; iii) used air conditioning and changes in clothing insulation as primary thermal resilience practices. Furthermore, certain individual factors (i.e. age, level of motor disability, experience of fatigue) were predictive of greater susceptibility to certain triggers (e.g. hot days) and symptoms (e.g. fatigue)., Conclusion: Patient-centred evidence on the impact of and response to temperature sensitivity could play an important role in the development of individualised healthcare plans for temperature-sensitive pwMS., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: The objective of this study was to evaluate skin wetness perception and thermal sensitivity in people with migraine and similar healthy controls., Background: Environmental triggers, such as cold and humidity, are known triggers for pain in people with migraine. Sensory inputs might be implicated in such heightened responses to cold-humid environments, such that a migraine-induced hypersensitivity to cold wetness could be present in people with migraine. However, we lack empirical evidence on skin thermal and wetness sensitivity across skin sites commonly associated with reported pain in migraine, such as the forehead., Methods: This prospective cross-sectional observational study, conducted in a university hospital setting, evaluated skin wetness perceptions and thermal sensations to wet non-noxious warm-wet, neutral-wet, and cold-wet stimuli applied to the forehead, the posterior neck, and the index finger pad of 12 patients with migraine (mean and standard deviation for age 44.5 ± 13.2 years, 7/12 [58%] women) and 36 healthy controls (mean and standard deviation for age 39.4 ± 14.6 years, 18/36 [50%] women)., Results: On the forehead, people with migraine reported a significantly higher wetness perception than healthy controls across all thermal stimulus (15.1 mm, 95% confidence interval [CI]: 1.8 to 28.5, p = 0.027, corresponding to ~ 15% difference), whereas no significant differences were found on the posterior neck nor on the index finger pad. We found no differences among groups in overall thermal sensations (-8.3 mm, 95% CI: -24.0 to 7.3, p = 0.291; -7.8 mm, 95% CI: -25.3 to 9.7, p = 0.375; and 12.4 mm, 95% CI: -4.0 to 28.9, p = 0.133; forehead, posterior neck, and index finger, respectively)., Conclusion: These findings indicate that people with migraine have a heightened sensitivity to skin wetness on the forehead area only, which is where pain attacks occur. Future studies should further explore the underlying mechanisms (e.g., TRPM8-mediated cold-wet allodynia) that lead to greater perception of wetness in people with migraine to better understand the role of environmental triggers in migraine., (© 2022 The Authors. Headache: The Journal of Head and Face Pain published by Wiley Periodicals LLC on behalf of American Headache Society.)

Mechanosensory inputs arising from dynamic interactions between the skin and moisture, such as when sliding a finger over a wet substrate, contribute to the perception of skin wetness. Yet, the exact relationship between the mechanical properties of a wet substrate, such as friction, and the resulting wetness perception remains to be established under naturalistic haptic interactions. We modeled the relationship between mechanical and thermal properties of substrates varying in moisture levels (0.49 × 10 -4 ; 1.10 × 10 -4 ; and 2.67 × 10 -4 mL·mm -2 ), coefficient of friction (0.783, 0.848, 1.033, 0.839, 0.876, and 0.763), and maximum thermal transfer rate ( Q max , ranging from 511 to 1,260 W·m -2 ·K -1 ), and wetness perception arising from the index finger pad's contact with such substrates. Forty young participants (20M/20F) performed dynamic interactions with 21 different stimuli using their index finger pad at a controlled angle, pressure, and speed. Participants rated their wetness perception using a 100-mm visual analog scale (very dry to very wet). Partial least squares regression analysis indicated that coefficient of friction explained only ∼11% of the variance in wetness perception, whereas Q max and moisture content accounted for ∼22% and 18% of the variance, respectively. These parameters shared positive relationships with wetness perception, such that the greater the Q max , moisture content, and coefficient of friction, the wetter the perception. We found no differences in wetness perception between males and females. Our findings indicate that although the friction of a wet substrate modulates wetness perception, it is still secondary to thermal parameters such as Q max . NEW & NOTEWORTHY Our skin often interacts with wet materials, yet how their physical properties influence our experience of wetness remains poorly understood. We evaluated wetness perception following naturalistic haptic interactions with materials varying in moisture content, friction, optical profiles, and heat transfer rates. We show that although mechanical parameters can influence wetness perception, their role is secondary to that of thermal factors. These findings expand our understanding of multisensory integration and could guide innovation in healthcare product design.

Background: A noticeable but unknown proportion of people with multiple sclerosis (pwMS) report the sudden experience of wetness on a dry skin site, i.e., phantom wetness. Yet, we lack patient-centred investigations on the prevalence and subjective experience of this uncomfortable symptom., Objectives: To assess the prevalence of phantom wetness in pwMS, its association with individual factors, and subjective experience., Methods: 757 pwMS completed an online survey assessing the frequency and subjective experience of phantom wetness. We calculated descriptive statistics and odd ratios and performed a thematic analysis to extract a patient-centred description of phantom wetness., Results: 220 participants reported experiencing phantom wetness (29%). Females and those affected by Relapsing Remitting (RR) MS were 2.17 [1.39, 3.34] (p<0.001) and 1.73 [1.23, 2.40] (p = 0.001) times as likely to experience phantom wetness as males and those not affected by RR MS, respectively. The thematic analysis indicated phantom wetness is more often experienced as water trickling on the skin of the lower limb., Conclusion: Phantom wetness is a paraesthesia occurring in almost a third of the sample surveyed. Clinicians are encouraged to discuss with pwMS to validate their experience as a genuine symptom. Using the patient-generated language we report may help facilitate such conversations., (Copyright © 2021 Elsevier B.V. All rights reserved.)

New Findings: What is the central question of this study? Ageing impairs the skin's thermal and tactile sensitivity: does ageing also induce loss of skin wetness sensitivity? What is the main finding and its importance? Older adults show an average 15% loss of skin wetness sensitivity, with this sensory deficit being mediated by a combination of reductions in skin's tactile sensing and hydration status. These findings increase knowledge of wetness sensing mechanisms across the lifespan., Abstract: Humans use sensory integration mechanisms to sense skin wetness based on thermal and mechanical cues. Ageing impairs the skin's thermal and tactile sensitivity, yet we lack evidence on whether wetness sensing also changes with ageing. We mapped local skin wetness and temperature sensitivity in response to cold-, neutral- and warm-wet stimuli applied to the forehead, neck, lower back, dorsal foot, index finger and thumb, in 10 Younger (22.4 ± 1.1 years) and 10 Older (58.2 ± 5.1 years) males. We measured local skin temperature and conductance (i.e., a marker of hydration status) at the tested sites, to establish the role of skin's thermal and mechanical parameters in ageing-induced changes in wetness sensing. Irrespective of body site, Older reported overall lower wetness perceptions than Younger across all wet-stimulus temperatures (mean difference: -14.6 mm; 95% CI: -4.3, -24.9; P = 0.008; ∼15% difference). When considering regional wetness sensitivity, the effect of ageing was more pronounced in response to the cold-wet stimulus over the lover back (mean difference Older vs. Younger: -36.8 mm; 95% CI: -68.4, -5.2; P = 0.014; ∼37% difference) and dorsal foot (mean difference: -37.1 mm; 95% CI: -68.7, -5.5; P = 0.013; ∼37% difference). We found no differences between age groups on overall thermal sensations (P = 0.744) nor local skin temperature (P = 0.372); however, we found that Older presented overall lower skin conductance than Younger (mean difference: -1.56 μS; 95% CI: -0.49, -2.62; P = 0.005), which corresponded to an ∼78% reduction in skin hydration. We conclude that skin wetness sensing decreases with ageing primarily due to age-induced changes in skin mechanics and tactile sensitivity., (© 2021 The Authors. Experimental Physiology © 2021 The Physiological Society.)