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Introduction Systemic cryotherapy is a popular treatment involving a short stay in a cryogenic chamber at a temperature below −100 °C. This leads to a number of physiological reactions, some of them also observed in the skin. The aim of the study was to analyze the effect of a single cryogenic treatment on selected skin characteristics (skin pH, level of hydration and TEWL – Transepidermal Water Loss) in young, healthy people. Materials and methods Skin characteristics in 77 young people (23.63 ± 1.36 years) were assessed. In the study, 43 women and 33 men who took part in a one-time treatment (−120 °C) lasting 3 min. Measurements were made on the forearm skin and (in men) on the face twice: before and immediately after the procedure. Results: Initial differences in hydration of the stratum corneum and TEWL were observed between the group of women and men. After one treatment, the examined characteristics of the forearm skin did not change, and an unfavorable increase in TEWL in men was indicated in the facial area. Conclusions A single stay in the cryogenic chamber, while maintaining the correct methodology of the treatment, is safe for the skin. The changes taking place depend on the body surface area tested, which indicates that the skin on the limbs and on the face reacts differently to the cryogenic stimulus.

Background : Skin is constantly exposed to mechanical and chemical insults, in the form of prolonged loading, overhydration or exposure to irritants. An array of non-invasive biophysical tools has been adopted to monitor the changes in skin response. The present study aims to identify a set of robust parameters sensitive to mechanical and chemical challenges to skin integrity. Materials and methods: Eleven healthy participants were recruited to evaluate the skin response following mechanical loading, tape-stripping, overhydration and chemical irritation. Forearm skin responses were recorded at baseline and at three time points following the insult. Measurements included transepidermal water loss, sub-epidermal moisture, erythema and laser Doppler imaging. Thresholds were informed by basal values and the sensitivity of parameters to detect skin changes was evaluated. Results: High degree of variability in skin response was observed with selected biophysical parameters, such as sub-epidermal moisture, laser Doppler imaging and erythema, even in the absence of an applied insult. Temporal skin response revealed distinct response profiles during each evoked insult. Indeed, the sensitivity of the biophysical parameters was influenced by the threshold values and time point of measurement. Some statistically significant correlations were determined between the biophysical parameters. Conclusion: The study revealed that thresholds derived from single biophysical parameters were limited in detecting skin changes following insults. A complementary evaluation using combined parameters has the potential to provide a more sensitive assessment. Further research is required to identify robust biophysical parameters, to aid the early detection of skin damage in clinical settings.

Background The accumulation of advanced glycation end products has been proposed as a causative agent of skin aging, but there are no conventional devices for quantifying advanced glycation end‐product accumulation in facial skin. Aims This study aimed to develop a convenient and accurate in situ advanced glycation end‐product measurement system for the human face. Methods We developed a facial glycation imaging system, which consisted of illumination (white light‐emitting diode, ultraviolet light‐emitting diode) and image acquisition modules to capture face images. Advanced glycation end product–related autofluorescence and total skin reflectance were calculated to obtain the skin glycation index using an image analysis algorithm. Correlations between the skin glycation index and facial skin elasticity and age were examined in 36 healthy Korean women. Results The facial glycation imaging system was validated against a volar forearm skin autofluorescence measurement device, that is, the AGE Reader mu, with forearm skin glycation index (R = 0.64, P

Rationale & objective: Arteriovenous fistula cannulation with the buttonhole technique is often preferred by patients but has been associated with an increased infection risk. Guidelines disagree on whether it should be abandoned, thus we assessed a technologically simple method to facilitate gentler arteriovenous fistula cannulation with potentially less discomfort and damage to the epithelial lining of the buttonhole tract. Study design: 8-week, prospective, open-label, randomized controlled trial. Setting & participants: Patients with buttonhole tracts receiving hemodialysis at 7 dialysis centers in Norway were randomized to the intervention group (43 patients, 658 cannulations) or control group (40 patients, 611 cannulations). Intervention: Direction and angle of the established buttonhole tract were marked on the forearm skin in the intervention group, whereas the control group had no structured cannulation information system. Outcomes: The primary outcome was successful cannulation, defined as correct placement of both blunt needles at the first attempt without needing to change needles, perform extra perforations, or reposition the needle. The secondary outcomes were patient-reported difficulty of cannulation (verbal rating scale: 1 = very easy, 6 = impossible) and intensity of pain (numeric rating scale: 0 = no pain, 10 = unbearable pain). Results: After a 2-week run-in period, successful cannulation was achieved in 73.9% and 74.8% of the patients in the intervention and control groups, respectively (relative risk [RR], 0.99; 95% CI, 0.87-1.12; P = 0.85). However, the probability of a difficult arterial cannulation (verbal rating scale, 3-6) was significantly lower in the intervention group (RR, 0.69; 95% CI, 0.55-0.85; P = 0.001). There were no improvements for venous cannulations. Furthermore, the probability of a painful cannulation (numeric rating scale, 3-10) was lower in the intervention group (RR, 0.72; 95% CI, 0.51-1.02; P = 0.06). Limitations: Unable to evaluate hard end points such as infections and thrombosis owing to the small sample size. Conclusions: Marking direction and angle of cannulation did not improve cannulation success rates; however, patients more often reported an unproblematic procedure and less pain. Funding: None. Trial registration: ClinicalTrials.gov (NCT01536548).

Summary Purpose After harvesting a radial forearm flap (RFF) an optimal aesthetic and functional restitution of the donor site is required. In order to cover the secondary defect of the donor site, several solutions are currently available, but there is still no real evidence of the most reliable option. A retrospective study was conducted in order to evaluate a new technique of forearm coverage with artificial dermis: the association of full thickness skin graft (FTSG) with Matriderm®. Methods Our study included all RFF performed during a 34-month period. Forty-three forearm secondary defects after harvesting a RFF (16 men, 27 female) were included. Forearm donor site was covered using three techniques: a simple FTSG, split thickness skin graft (STSG) with Matriderm® or FTSG with Matriderm®. Clinical evaluations based on residual functionality, skin quality and aesthetic result were assessed using respectively the Disabilities of the Arm, Shoulder and Hand (DASH) score, the Vancouver Scar Scale (VSS) score and a blind panel questionnaire. Results FTSG with Matriderm® showed an improved DASH (10.6/100) and VSS score (5.5/13) if compared to the other techniques, mean surgeon satisfaction score was 3/5, mean patient satisfaction score was 3/5 in the FTSG with Matriderm® group. Conclusion The results of this study revealed that the new association of FTSG with Matriderm® improves the DASH score and the aesthetic outcomes resulting to be a reliable solution in treating full thickness forearm skin defects after RFF harvesting.

Background.Hypertension (HTN) is associated with impaired skin microcirculation. Laser Doppler flowmetry is an objective, quantitative, instrumental method that allows evaluating skin microcirculation. However, the method was not widely used clinically due to high variability of perfusion and small difference between healthy people and HTN patients and, as a consequence, low diagnostic signifcance.Objective.To provide the grounds for the approaches increasing the informative value of skin microcirculation measurement by laser Doppler flowmetry in HTN patients.Design and methods.The study involved HTN patients (n = 13, the median age was 60 (49; 63) years) and young otherwise healthy volunteers without HTN (n = 12, the median age 26 (25; 27) years). Microcirculation measurement was performed by laser Doppler flowmetry using LAKK-02 device. Registration of microcirculation on the forearm skin was carried out during the occlusionheating test. The Mann-Whitney test was used to compare the parameters in two groups. The diagnostic accuracy of the method for the inverse classifcation of the subjects was evaluated using ROC analysis.Results.In HTN patients, the median baseline perfusion was 3,1 (1,84; 4,31) perfusion units (PU), in healthy volunteers — 4,29 (3,66; 8,14) PU (p = 0,04). The median area under the microcirculation curve for the frst 2 minutes of heating in HTN patients was 1206,7 (813; 1449) PU × s, in healthy volunteers — 1552,3 (1310; 1624) PU × s (p = 0,035). In healthy volunteers, the heating increased the perfusion by 596 % (386%; 878%), and in HTN patients perfusion increased only by 265% (180 %; 318%) (p = 0,01). The relative increase in perfusion during postocclusion hyperemia with continued heating compared with the baseline in healthy volunteers was 651% (493 %; 999%), and in HTN patients — 302 % (182 %; 436%) (p = 0,005). Thus, when comparing the average parameters for each period in the occlusion-heating test, only basic perfusion showed signifcant differences. However, when changed from absolute to relative parameters (the increase in microcirculation in relation to the vasodilating effects), the difference was signifcant. Moreover, sensitivity achieved was 75 % and specifcity — 84,6% (the inverse classifcation of groups).Conclusions.The physiological (the local heating of the forearm skin at a rate of 2 degrees Celsius per second, a combination of vasodilating effects) and mathematical (the transition from absolute to relative values) approaches provided an increase of the informative value of the laser Doppler flowmetry, as well as its sensitivity and specifcity.

Background Skin occlusion caused by the use of diapers or sanitary napkins often results in irritant contact dermatitis. Furthermore, prolonged occlusion and exposure to body fluids are known to increase skin hydration and permeability, thus leading to irritant contact dermatitis. Objective To investigate the effects of water exposure on the skin and its barrier functions, in order to obtain more insights into the mechanisms of irritant contact dermatitis. Methods Water patches were applied to the volar forearm skin of 10 human subjects for 3 hours. Permeability of the stratum corneum (SC) was examined with methyl nicotinate (MN). Alterations in the hydration and ultrastructure of the SC were measured with Raman spectroscopy and multiphoton microscopy, respectively. Results Water profiles found with Raman spectroscopy showed notable increases in water content throughout the SC and skin surface. Multiphoton microscopy showed morphological changes in the intercellular space of the SC. Emerged pools seemed to contribute to increased MN absorption. Conclusion Excessive skin hydration leading to changes in the SC ultrastructure might result in increased skin permeability to skin irritants and allergens.

Peripheral hemodynamics was studied in the upper extremities of human subjects during a 5-day exposure in microgravity modeled by “dry” immersion (DI). The object of investigation was skin adjacent to the nail bed of the fourth finger and forearm skin. Microcirculation was measured using laser Doppler flowmetry (LDF) and computer capillaroscopy (CCS). In addition, peripheral hemodynamics was assessed in subjects donned in a Penguin axial-loading suit (PLS). The subjects were divided into two groups: with (G-2) and without (G-1) PLS. The results are the following: PLS leveled down all changes in the microcirculatory bloodstream (MCB) of the upper extremities. By the end of DI, some subjects in G-1 were found to have a more intensive tissue perfusion and increased number of capillaries, and exaggerated activity of passive mechanism of blood flow modulation Ас (one-way ANOVA, p < 0.05).

Background Visual and molecular changes occurring upon aging are rather well characterized. Still, aging signs show great significant inter-individual variations, and little is known concerning the link between perceived age and cutaneous microcirculation. Materials and methods To investigate this point, we recruited Caucasian women in their mid-50's to mid-70's and subsampled women looking older or younger than their age. We studied their facial skin color, as well as their microvascular reactivity to local heating assessed in the forearm skin. We also used skin biopsies from some of these women for gene expression or immunohistochemical analysis. Results Clinical and instrumental analysis of skin color revealed that subjects who look 5 years younger differ only by a higher glowing complexion. Our most striking result is that subjects looking 5 years younger than their age present a higher microcirculation reactivity in forearm skin. Transcriptome comparison of skin samples from women looking older or younger than their age revealed 123 annotated transcripts differentially expressed, among which MYL9 relates to microcirculation. MYL9 is downregulated in the group of women looking younger than their real age. Microscopy shows that the labeling of MYL9 and CD31 are altered and heterogeneous with age, as is the morphology of microvessels. Conclusion Therefore, assessing generalized vascular reactivity in non-photo-exposed skin to focus on the intrinsic aging allows subtle discrimination of perceived age within elderly healthy subjects.

BACKGROUND The reverse posterior interosseous artery flap is useful for covering hand defects. However, its major drawback is the short pedicle that limits the reach of the flap up to the metacarpophalangeal level. The authors performed a new modification extending the distal reach of the flap by including the recurrent branch of the posterior interosseous artery and they aimed to present the results of reconstruction with this technique. PATIENTS AND METHODS Seven patients with a mean age of 35.2 years (range 17-64 years) underwent extended RPIAF surgery. Six patients were admitted to the emergency department with isolated hand trauma. One patient was present in elective settings with chronic osteomyelitis and skin loss of the thumb related to previous trauma. The defects were located on the distal metacarpophalangeal level (thumb and other fingers). PIA perforators and the recurrent branch were included into the pedicle (Type A) in five cases, whereas the flap was harvested based solely on the recurrent branch (Type B) in two cases. The type B flaps had longer pedicle lengths due to discarding the forearm skin. The donor sites were covered with skin grafts in six patients. RESULTS The average size of the extended RPIAF was 3 × 3.5 cm to 10 × 6 cm (mean 8.28 × 4.14 cm). All of the flaps completely survived, and no complications were encountered during the postoperative period. Functional recovery of the operated hands were observed during the follow up period 13.5 months (8-24 months). Both the patient and our satisfactory levels were high and all of the patients returned to their works. Quick DASH score was used in the final functional evaluation retrospectively. Due to the pandemic, the evaluation could be made with a telephone. Two patients could not be reached in the evaluation. The mean quick DASH score of five patients was 28.64. CONCLUSION The extended RPIAF is a reliable choice in distally located thumb and finger defects if the recurrent branch of the posterior interosseous artery is included in the pedicle.

To evaluate the effect of illumination, camera orientation, and camera distance on color consistency of different skin tones, several swatches from a Pantone SkinTone Guide deck were selected and photographed at varying distances, illuminations, and angles. The RGB values from each selected swatch from each image were converted to LAB units and compared with the converted “true” values provided by Pantone. The ability of various color references to correct different skin tones was tested by comparing color values from a subject’s forearm skin to “true” color values of the closest Pantone SkinTone swatch found by visual comparison.

This chapter describes the procedure for harvesting radial forearm flap (RFF) in a porcine model and details the flap vascular anatomy. The illustrations represent in the chapter allow visualizing the anatomical model of this area. In the porcine model, the vascularized area of forearm skin differs from humans. The radial artery supplies a smaller area of the skin. The deep location of the vascular bundle is the main difference in the surgical anatomy of radial forearm flap from the human.

© 2021 Editorial Council for the Journal of Prosthetic DentistryStatement of problem: A commercially available computerized color matching system (e-Skin) has been introduced for maxillofacial prostheses. However, studies that have tested its ability to produce an acceptable color match for skin color are lacking. Purpose: The purpose of this clinical study was to determine the color match acceptability of light and dark skin silicone replicas fabricated with the use of the computerized color matching system. Material and methods: Fifteen participants with light skin and 15 participants with dark skin were recruited through personal invitation. These 30 participants (aged around 20 years) voluntarily consented to forearm skin color measurements with a spectrophotometer and a spectrocolorimeter integrated in a computerized color matching system. Silicone skin replicas for each participant were produced from the color formulations provided by the online calculator tool of the system according to the manufacturers’ recommendations. The color difference between initial skin color measurements with the spectrophotometer and skin replica color measurements with the spectrophotometer for all participants was calculated by using both the CIELab (ΔE∗ab) and CIEDE2000 (ΔE00) color difference formulas. To compare the instrumental and visual evaluation of color match, 3 observers (a maxillofacial prosthodontist, a prosthodontist, and a postgraduate student) visually evaluated and rated the color match of each silicone replica on a 5-point scale. Statistical analyses were performed by using the Student t, Mann Whitney U, and chi-square tests (α=.05). Results: No significant differences were detected between the light and dark skin groups in terms of the ΔE∗ab and ΔE00 values obtained between the first skin color measurements and their silicone replica color measurements (P=.573, P=.338, respectively). However, a significant difference was found between light and dark skin groups for the ΔL and Δa values obtained from the same measurements (P=.031, P=.017, respectively). L∗, a∗, and b∗ values of light skin were significantly higher than those of their silicone replications (P=.008, P=.033, P=.046, respectively). Color match ratings of observers did not significantly differ when comparing the ratings of light skin replicas to ratings of dark skin replicas. Conclusions: The e-Skin system provided skin replicas that matched the skin color within clinically acceptable thresholds and with ratings of at least “good” by experienced dental clinicians.

The object of this paper is in vivo study of skin spectral-characteristics in patients with kidney failure by conventional Raman spectroscopy in near infrared region. The experimental dataset was subjected to discriminant analysis with the projection on latent structures (PLS-DA). Application of Raman spectroscopy to investigate the forearm skin in 85 adult patients with kidney failure (90 spectra) and 40 healthy adult volunteers (80 spectra) has yielded the accuracy of 0.96, sensitivity of 0.94 and specificity of 0.99 in terms of identifying the target subjects with kidney failure. The autofluorescence analysis in the near infrared region identified the patients with kidney failure among healthy volunteers of the same age group with specificity, sensitivity, and accuracy of 0.91, 0.84, and 0.88, respectively. When classifying subjects by the presence of kidney failure using the PLS-DA method, the most informative Raman spectral bands are 1315 to 1330, 1450 to 1460, 1700 to 1800 cm-1 . In general, the performed study demonstrates that for in vivo skin analysis, the conventional Raman spectroscopy can provide the basis for cost-effective and accurate detection of kidney failure and associated metabolic changes in the skin.

Spatiotemporal optical coherence (STOC) imaging is a novel technique for suppressing coherent cross-talk noise in full-field swept-source OCT (FF-SS-OCT). In STOC, we use time-varying phase masks to modulate light incident on the sample. The modulated signals are averaged incoherently or coherently to yield cross-talk-free 3D images of the sample. We show that coherent averaging is only possible under specific hardware configuration. We explain this theoretically and confirm experimentally by imaging USAF chart covered by diffusers and the rat skin ex vivo. Finally, we present human forearm skin imaging in vivo. In all cases, STOC imaging reveals otherwise invisible sample features.

Skin-remitted picosecond laser pulses were detected at four input-output fiber distances in the spectral range 560-800 nm. After deconvolution procedures, distributions and mean values of the remitted photon path lengths in forearm skin were analyzed.

Background The reproducibility and reliability of the modified Rodnan’s Skin Score (mRSS) are debated due to investigator-related subjectivity. Here, we evaluate if durometry correlates with mRSS in patients with diffuse systemic sclerosis (SSc). Methods This cross-sectional study was conducted from December 2018 to June 2019, including 58 diffuse SSc patients. Two certified researchers, blind to each other’s scores, performed the mRSS, followed by durometry at 17 predefined skin sites. For durometry and mRSS, individual scores per skin site were registered. Durometry and mRSS results measured by each researcher, as well as scores from different researchers, were compared. Skin thickness measurements from forearm skin biopsies were available in a subset of the patients, for comparisons. Statistical analyses included Cohen’s Kappa Coefficient, Intraclass Correlation Coefficient, Kendall’s Coefficient and Spearman’s test. Results Mean (standard deviation, SD) patient age was 44.8 (12.9) years, and 88% were female. Inter-rater agreement varied from 0.88 to 0.99 (Intraclass correlation coefficient) for durometry, and 0.54 to 0.79 (Cohen’s Kappa coefficient) for mRSS, according to the specific evaluated sites. When data were compared with skin thickness assessed in forearm biopsies, durometry correlated better with skin thickness than mRSS. Conclusion Durometry may be considered as an alternative method to quantify skin involvement in patients with diffuse SSc. The strong inter-rater agreement suggests that the method may be useful for the assessment of patients by multiple researchers, as in clinical trials.

Incontinence-associated dermatitis is common among wearers of absorbent incontinence products and friction between product materials and skin is thought to be a contributing factor, but the details of its role are unclear. In this study, friction was measured between the dry volar forearm of 19 women (20-95 years) and five nonwovens typical of those in commercial disposable products. Euler's model/Amontons' law held to high precision for all person-fabric pairs for both static and dynamic friction, despite substantial variations in forearm size, soft tissue compliance and skin smoothness between subjects, sometimes substantial lateral contraction in fabric strips, and skin rucking beneath them. For a given subject, the highest coefficients of friction among the fabrics exceeded the lowest by ∼30% to 75%, while - for a given fabric - the highest coefficients of friction among the subjects exceeded the lowest by ∼55% to 85%. The order of coefficient of friction values across fabrics was similar for each subject, and across subjects for each fabric. There was no systematic variation with subject age. The data were well modelled by estimating the coefficients of friction for a given person-fabric combination as the product of the mean coefficient of friction across all fabrics for that person, and the mean coefficient of friction across all persons for that fabric, normalised to the mean coefficient of friction across all person-fabric combinations. Predicted values were within 10% of measured figures for ∼97% of person-fabric combinations. Stick-and-slip behaviour was observed with seven person-fabric combinations, but especially strongly for two subjects with each of two fabrics. It is not clear why and further investigation is merited. Comparison of the data with results from earlier work with the same fabrics and a skin surrogate (Lorica Soft) suggests that measurements with Lorica Soft may be helpful to screen, evaluate and compare candidate materials preparatory to human studies.

A novel biomedical instrument for supporting the physician in Skin Prick Test analysis was designed, developed, characterized, and is now ready for clinical trials. Skin Prick Test is the gold standard front-end analysis for diagnosis of allergies in human subjects. The forearm skin is punctured with different allergens and the resulting reaction wheals are analyzed and compared to standard reaction, with larger areas corresponding to stronger allergy to the specific allergen. The wheals inspection and allergy diagnosis are performed, visually and subjectively, by the Medical Doctor. This procedure is laborious and somehow unreliable, being subject to variability both intra- and inter-operator because the doctor subjectivity in detecting and measuring the wheals is significant. Registration of the exam result is rarely available in a digital format, useful for data saving, transmission, retrieval and comparative analyses. Many of the above criticalities of the actual Prick Test manual practice are addressed and resolved by the proposed biomedical instrumentation that makes use of digital image-processing and data storage. In this work, we present a prototype of wheal measurement system, designed, developed and characterized to specifically measure geometry and areas of the allergic reaction wheals in Prick Test clinical exams. After software developments from previous version of the instrument, the wheal-meter now allows manual, semi-automatic, automatic, and fully-automatic operating conditions always providing digital exams output.

Background: Breath acetone is reported to be a noninvasive biomarker for heart failure. However, the measurement of this metabolite requires expertize and is not standardized yet. Acetone is also released from the skin; thus, measuring acetone as a skin gas may be easier than breath analysis. Methods: We analyzed skin acetone collected from 41 hospitalized patients with cardiovascular diseases. Passive samplers were used to measure skin acetone emission. Passive sampler was softly fixed on the surface of forearm skin for 10 hour at night. Results: Skin acetone emission ranged from 0.00 to 2.70 ng/cm2/h, and was significantly correlated with blood ketone bodies (r = 0.377, p = 0.017). Conclusions: This is the first study to analyze skin gas in patients with cardiovascular diseases. Skin acetone emission was found to reflect blood ketone bodies. It is feasible to measure skin acetone emission for reflecting blood ketone bodies in patients with cardiovascular diseases.

BACKGROUND Quantitative assessment of possible linkages between skin's firmness and water content is useful for cosmetic and clinical purposes and to better understand features of advancing age. OBJECTIVES Our goals were to characterize age-related differential features in skin firmness in women and determine the relationship between skin firmness and indices of skin water. METHODS Skin firmness was quantified using handheld devices that measure the force to indent skin 0.3 and 1.3 mm (F0.3 and F1.3). Skin hydration was quantified using handheld devices that measured tissue dielectric constant (TDC) at 300 MHz to skin depths of 0.5 and 2.0-2.5 mm. All parameters were measured bilaterally in the jowl area and volar forearm of 60 women grouped by age

Skin texture without obvious features is different from other hard biometrics on the skin, such as fingerprints and palmprints. Skin texture gives an impression that it is not distinctive like other soft biometric traits. It was proposed for personal identification a decade ago but did not draw attention from the biometric community, partially due to the success of other biometric technologies for commercial applications. However, in some forensic cases, e.g., identifying masked terrorists in images, skin texture may be the only option. Faces, tattoos, and skin marks are not always available for identification. To address these forensic needs, researchers have recently attempted to visualize blood vessels hidden in color images. Their performance is highly sensitive to image quality. Skin texture that is easily captured even in low-resolution images, such as that of the forearm skin, is suitable for these forensic applications. To study the distinctiveness of low-resolution skin texture, in this paper, an algorithm composed of a positive sample generation scheme, dynamic and directional grids, a large feature set generation scheme, and partial least squares regression has been proposed. More than 6300 inner forearm and thigh images collected from a laboratory environment and from the internet with large pose, viewpoint, and illumination variations were employed in this paper. The proposed algorithm was compared with the state-of-the-art texture recognition methods, and skin texture was compared with blood vessels, a hard biometric trait, extracted from color and infrared images. The results showed that the proposed algorithm performed significantly better than did the texture recognition methods, and skin texture outperformed blood vessels in all of the experiments, achieving encouraging performance.

Several studies have shown that advanced glycation end products (AGE) play a role in both the microvascular and macrovascular complications of diabetes and are closely linked to inflammation and atherosclerosis. AGEs accumulate in skin and can be detected using their auto fluorescence (AF).A significant correlation exists between AGE AF and the levels of AGEs as obtained from skin biopsies. A commercial device, the AGE Reader, has become available to assess skin AF for clinical purposes but, while displaying promising results, it is limited to single-point measurements performed in contact to skin tissue. Furthermore, in vivo imaging of AGE accumulation is virtually unexplored.We proposed a non-invasive, contact-less novel technique for quantifying fluorescent AGE deposits in skin tissue using a multispectral imaging camera setup (MSI) during ultraviolet (UV) exposure. Imaging involved applying a region-of-interest mask, avoiding specular reflections and a simple calibration. Results of a study conducted on 16 subjects with skin types ranging from fair to deeply pigmented skin, showed that AGE measured with MSI in forearm skin was significantly correlated with the AGE reference method (AGE Reader on forearm skin, R=0.68, p=0.005). AGE measured in facial skin was borderline significantly related to AGE Reader on forearm skin (R=0.47, p=0.078). These results support the use of the technique in devices for non-touch measurement of AGE content in either facial or forearm skin tissue over time. SEMEOTICONS

The measurement of perceptual sensitivity can be used for the clinical diagnosis and assessment of skin conditions. However, conventional approaches to evaluating the direct relationship between perceptual sensitivity and the skin mechanical properties have limitations. This study proposed a new approach to achieving the simultaneous measurement of skin deformation and perceptual sensitivity. We introduced suction stimulation on the skin, which is commonly used for evaluating the skin mechanical properties. However, the standard suction stimuli cannot produce sufficient stimuli to be perceived. We solved this issue by applying oscillated suction pressure in the frequency of 10 Hz. We presented the device mechanism and control method of the pressure. As a pilot study, we investigated the relationship between the deformation of the forearm skin and perceptual sensitivity in thirteen participants. Experimental results suggested that the amount of skin displacement achieves better discrimination performance than the suction pressure levels.

For many applications, hand gesture recognition systems that rely on biosignal data exclusively are mandatory. Usually, theses systems have to be affordable, reliable as well as mobile. The hand is moved due to muscle contractions that cause motions of the forearm skin. Theses motions can be captured with cheap and reliable accelerometers placed around the forearm. Since accelerometers can also be integrated into mobile systems easily, the possibility of a robust hand gesture recognition based on accelerometer signals is evaluated in this work. For this, a neural network architecture consisting of two different kinds of recurrent neural network (RNN) cells is proposed. Experiments on three databases reveal that this relatively small network outperforms by far state-of-the-art hand gesture recognition approaches that rely on multi-modal data. The combination of accelerometer data and an RNN forms a robust hand gesture classification system, i.e., the performance of the network does not vary a lot between subjects and it is outstanding for amputees. Furthermore, the proposed network uses only 5 ms short windows to classify the hand gestures. Consequently, this approach allows for a quick, and potentially delay-free hand gesture detection.

The introduction of a strain or consortium has often been considered as a potential solution to restore microbial ecosystems. Extensive research on the skin microbiota has led to the development of probiotic products (with live bacterial strains) that are likely to treat dysbiosis. However, the effects of such introductions on the indigenous microbiota have not yet been investigated. Here, through a daily application of Lactobacillus reuteri DSM 17938 on volunteers’ forearm skin, we studied in vivo the impact of a probiotic on the indigenous skin bacterial community diversity using Terminal-Restriction Fragment Length Polymorphism (T-RFLP) for 3 weeks. The results demonstrate that Lactobacillus reuteri DSM 17938 inoculum had a transient effect on the indigenous community, as the resilience phenomenon was observed within the skin microbiota. Moreover, Lactobacillus reuteri DSM 17938 monitoring showed that, despite a high level of detection after 2 weeks of application, thereafter the colonization rate drops drastically. The probiotic colonization rate was correlated significantly to the effect on the indigenous microbial community structure. These preliminary results suggest that the success of probiotic use and the potential health benefits resides in the interactions with the human microbiota.

Purpose Transcutaneous oxygen tension (TcpO2 ) provides information about blood perfusion in the tissue immediately below the skin. These data are valuable in assessing wound healing problems, diagnosing peripheral vascular/arterial insufficiency, and predicting disease progression or the response to therapy. Currently, TcpO2 is primarily measured using electrochemical skin sensors, which consume oxygen and are prone to calibration errors. The goal of the present study was to develop a reliable method for TcpO2 measurement in human subjects. Methods We have developed a novel TcpO2 oximetry method based on electron paramagnetic resonance (EPR) principles with an oxygen-sensing skin adhesive film, named the superficial perfusion oxygen tension (SPOT) chip. The SPOT chip is a 3-mm diameter, 60-μm thick circular film composed of a stable paramagnetic oxygen sensor. The chip is covered with an oxygen-barrier material on one side and secured on the skin by a medical adhesive transfer tape to ensure that only the oxygen that diffuses through the skin surface is measured. The method quantifies TcpO2 through the linewidth of the EPR spectrum. Results Repeated measurements using a cohort of 10 healthy human subjects showed that the TcpO2 measurements were robust, reliable, and reproducible. The TcpO2 values ranged from 7.8 ± 0.8 to 22.0 ± 1.0 mmHg in the volar forearm skin (N = 29) and 8.1 ± 0.3 to 23.4 ± 1.3 mmHg in the foot (N = 86). Conclusions The results demonstrated that the SPOT chip can measure TcpO2 reliably and repeatedly under ambient conditions. The SPOT chip method could potentially be used to monitor TcpO2 in the clinic.

Background Knowledge about the required duration of exposure for elicitation of allergic nickel dermatitis in nickel-allergic individuals is limited. However, it often has been proposed that short skin contact is safe. Objectives To examine whether repeated skin contact with nickel over short time periods (3 × 10 min) can elicit allergic nickel dermatitis. Methods Sixteen nickel-allergic adults and 10 controls were exposed to, respectively, nickel- and aluminium-containing discs on each volar forearm and on each earlobe for 3 × 10 min. One arm was pretreated for 24 h with sodium lauryl sulfate (SLS) 0·5% under occlusion before exposure. One aluminium and one nickel exposure site were clinically evaluated, and blood flow was measured with laser Doppler flowmetry at day 2 and day 4. Results Ten of 16 (63%) nickel-allergic participants developed allergic nickel dermatitis on SLS-pretreated arm skin and three of 16 (19%) developed it on normal skin on the earlobe. On the SLS-pretreated arms of nickel-allergic participants, blood flow increased significantly more on the nickel-exposed skin than on the aluminium-exposed skin on days 2 and 4. No change in clinical reactivity or blood flow was found on normal forearm skin in nickel-allergic participants or on any skin in controls. Conclusions This experimental study showed that relatively short repeated skin contact (3 × 10 min) with metallic nickel elicits allergic nickel dermatitis in irritated skin and at sites with previous dermatitis. The results support the restrictions in current nickel regulation.

In this study, we performed osteosynthesis for a distal radius fracture using a minimally invasive approach for a patient with skin disorder of the forearm and obtained favorable results. This case report may provide new findings confirming the usefulness of this surgical approach for distal radius fractures. Blister formation on the right forearm was observed in a 53-year-old female who was diagnosed with a distal fracture of the right radius and underwent splinting in a local hospital, and she was referred to our hospital 2 days after the injury. Minimally invasive locking plate osteosynthesis was performed, and there was no skin lesion at this incision site. Postoperatively, there were no complications in soft tissues and the operative scar was almost unrecognizable. We reported volar locking plate osteosynthesis using the minimally invasive approach in a patient with skin disorder of the forearm. Such patients are rarely encountered. However, this minimally invasive approach is extremely useful for utilizing the advantages of volar locking plate fixation without being affected by the soft tissue environment.

Due to their microscopic size, ubiquity, and resistance to destruction, pollen grains are an especially valuable biological material that can be used in forensic investigations.Determination of the species composition of pollen grains deposited on the clothing and skin of the people walking in Włodawa County during the summer.Pollen grains deposited on the surface of the skin and garments of individuals walking in four villages of Włodawa County were analysed. The material was sampled using two-sided adhesive tape. The qualitative and quantitative composition of pollen grains was evaluated after analysis of microscopic slides at 400-x magnification.In the present investigations, we identified pollen grains of plants flowering in summer, i.e. in the experimental period. The palynological analyses indicate that the surface of clothes on the shoulders and the surface of the forearm skin are the most suitable areas for deposition of pollen grains, whereas the lowest amounts of pollen were noted on the calves. The statistical analysis shows that the differences in the number of sporomorphs deposited on the different surfaces are not statistically significant.Palynological material collected from suspects or victims should be taken from various parts of clothing and skin, because it does not attach to them in the same way.Ziarna pyłku ze względu na mikroskopijne rozmiary, wszechobecność i odporność na zniszczenie stanowią niezwykle cenny materiał biologiczny, który może być wykorzystany w postępowaniu dochodzeniowym.Określenie składu gatunkowego ziaren pyłku osadzonych na ubraniu i skórze ciała osób spacerujących w okolicach powiatu włodawskiego w okresie letnim.Badaniom zostały poddane ziarna pyłku zdeponowane na powierzchni skóry i elementach garderoby osób spacerujących w czterech miejscowościach powiatu włodawskiego. Materiał pobierano na preparaty z taśmą dwustronnie klejącą. Skład jakościowy oraz ilościowy ziaren pyłku oceniono po analizie preparatów mikroskopowych przy powiększeniu 400-krotnym.W przeprowadzonych badaniach zidentyfikowano ziarna pyłku roślin kwitnących w lecie, czyli w okresie, w jakim został przeprowadzony eksperyment. Z analizy palinologicznej wynika, że najdogodniejszym miejscem osadzania się ziaren pyłku jest powierzchnia ubrania na ramionach oraz powierzchnia skóry na przedramionach, natomiast najmniej ziaren znaleziono na powierzchni skóry na łydkach. Z analizy statystycznej wynika, że różnice w liczebności sporomorf zdeponowanych na różnych powierzchniach nie są istotne statystycznie.Materiał palinologiczny zabezpieczany z podejrzanych lub ofiar powinien być pobierany z różnych części ubrania i skóry, ponieważ nie przyczepia się do nich w jednakowy sposób.

Many people sometimes imagine if they can wield superhuman abilities like that appear in games and animation. Among these abilities, we focused particularly on representing the experience of arm stretching beyond the limits of the human body. We proposed a method for inducing a sense of arm stretching by designing the device attached to forearm and giving the user a visual cue by changing the body structure of the user's avatar in the virtual environment. Our device shifts the mass from the elbow to the wrist while stretching the skin of the forearm according to the animation in the virtual environment. The sensation of the elongation of the arm skin as well as the change in the weight of arm is thought to be the feeling when the arms are stretched out. As a result, we introduce these two mechanisms into our device, which allows the user to feel the sense of arm stretching.

Combination of diffuse reflectance spectroscopy (DRS) and pulsed photothermal radiometry (PPTR) was recently successfully used to study evolution of accidental traumatic bruises. Yet, accidental bruises introduce many unknowns into the evolution analysis and thus a more controllable and repeatable approach for bruising is desired. In this study, evolution of bruises induced by aluminum projectiles of known mass and velocity were studied by DRS and PPTR. Bruises were induced on volar forearm skin of two healthy volunteers. Inverse Monte Carlo including four-layer skin model, was used to analyze the DRS and PPTR data to determine skin chromophores, their concentrations and depths. For bruise analysis, a bruise model was constructed and evolved according to hemoglobin diffusion kinetics. Bruise analysis of PPTR signals yielded bruise evolution parameters, most importantly hemoglobin diffusion constant, hemoglobin decomposition time and blood pool depth. The study results show that chronological tracking of hemoglobin decomposition can be assessed by the combined DRS and PPTR technique on induced bruise. Parameters of individual bruises were compared and two trends in chronological behavior of hemoglobin decomposition time discerned. Changes in bruise diffuse reflectance spectra were noted. Induced bruise parameters, however, still showed some scatter and thus further research is needed to reduce bruise variability.

This study investigated the noradrenergic contribution during the cutaneous vasoconstrictor response to local cooling in the leg and forearm. On each limb, one site was perfused with Yoh/Prop to block the postsynaptic adrenoceptors and another with Lactated Ringer's (control) using microdialysis. Blood flow was measured by Laser-Doppler flowmetry (LDF). Cutaneous vascular conductance (CVC) was calculated as LDF units divided by the mean arterial pressure. After baseline measures, skin was locally cooled to 24°C. Basal CVC was similar at all sites in the leg and forearm (all p > 0.1). During the first 10 min of local cooling, CVC was reduced in the leg (p < 0.005) and unchanged in the forearm control sites (p = 0.2). Yoh/Prop induced an increased CVC in the leg and forearm to a similar level (39.2 ± 11.5, and 41.3 ± 3.3%CVC, respectively; p < 0.35). Late during local cooling, the vasoconstriction was attenuated in the leg and forearm at Yoh/Prop (-38.2 ± 5.3 -37.1 ± 5.3%CVC, respectively; p = 0.5) compared to control sites (-69.1 ± 5.8 vs. -54.5 ± 6.4%CVC, respectively; p < 0.005). Noradrenergic contribution was greater in the leg than the forearm during the late vasoconstrictor response (p = 0.006). These data indicate that the leg skin can induce greater vasoconstriction than forearm during local cooling, possibly via higher noradrenergic sensitivity in the leg skin.

Microvascular dysfunction is a potential factor explaining the association of obesity, insulin resistance, and vascular damage in morbidly obese subjects. The purpose of the study was to evaluate possible determinants of microcirculatory improvement 1 year after laparoscopic sleeve gastrectomy (LSG) intervention. Thirty-seven morbidly obese subjects eligible for bariatric surgery were included in the study. Post-occlusive reactive hyperemia (PORH) of the forearm skin was measured as area of hyperemia (AH) by laser-Doppler flowmetry before LSG and after a 1-year follow-up. After intervention, we observed a significant reduction in BMI, HOMA index, HbA1c, and a significant increase of AH in all patients after surgery; this variation was significant only in those patients having insulin resistance or prediabetes/diabetes. Although significant correlation between the increase of AH and the reduction of both BMI, HOMA index, and HbA1c was observed, BMI was the only independent predictor of AH variation after LSG at the linear regression analysis. Our study shows that LSG intervention is correlated with a significant improvement in the microvascular function of morbidly obese subjects; this improvement seems to be related to the baseline degree of insulin-resistance and to the retrieval of insulin-sensitivity post-intervention.

Background: Despite the focus on facial photoaging ratings, there are few classifications developed for forearm skin aging assessment. Objective: To develop and validate a clinical scale for the evaluation of forearm skin aging. Methods: Three clinical dermatology faculty members selected, discussed, and appraised the main signs of forearm photoaging. The validation of the resulting scale was performed by 5 assessors who were previously trained to classify 102 photographs of forearms with different degrees of aging. Retests were performed in 15 days. Results: There was significant correlation between the selected variables and the subjective global aging scale. The developed scale showed high internal consistency (Cronbach’s α = 0.87) and high correlation with the global photoaging scale (rho = 0.92). Inter- and intraobserver final scores showed high agreement. Conclusion: A validated clinical photoaging scale for forearms with internal consistency, reliability, and validity was developed.

Topical skin protectants (barrier creams) have the potential to reduce or enhance the severity of dermal lesions following exposure to allergens or irritants. Therefore, it is essential that such products are subject to appropriate clinical evaluation prior to marketing. Consequently, it is important to accurately define a dosing regime in order to assess test products under appropriate conditions.In this study, we extended the use of a standard rubefacient (methyl nicotinate; MN) assay to establish the optimum thickness and duration of action of a novel barrier cream (RD1433). White petroleum jelly (Vaseline(®)) was used as a comparator product.The dermal response to MN was measured on the volar forearm skin of volunteers (n = 12; average age 47.5 years) using an array of biophysical instruments and visual scoring. When applied at a nominal thickness of 0.1 mm, RD1433 retained effectiveness against MN for up to six hours. In contrast, Vaseline(®) was relatively ineffective. Moreover, RD1433 provoked no measurable signs of irritation and so can be considered acceptable for further clinical evaluation.Future clinical studies using RD1433 should be based on topical application of a 0.1 mm thickness layer every six hours.

The present study investigated the effect of dynamic handgrip exercise on acetone, 6-methyl-5-hepten-2-one, acetaldehyde, and hexanal levels in skin gas. Participants in this experiment consisted of six healthy males. Skin gas was collected two times. First, skin gas during rest (i.e., before the exercise) was collected for 3 min into the sampling bag. Next, the exercise using a handgrip exercise instrument was performed. The hand performed a dynamic handgrip exercise for 3 min inside the sampling bag, exerting one 30 kg contraction per second. The blood flow at the end of the handgrip exercise increased by about 1.4 times that before exercise and then decreased to basal levels immediately thereafter. Acetone and 6-methyl-5-hepten-2-one concentrations after exercise significantly increased relative to basal levels. Significant differences were not observed in acetaldehyde and hexanal concentrations between at rest and after handgrip exercise. The amount of acetone and 6-methyl-5-hepten-2-one released from forearm skin increased during dynamic handgrip exercise. Acetaldehyde and hexanal levels did not increase during exercise compared with levels at rest.

Background To support internal compound development in systemic sclerosis, a study was performed to identify an mRSS signature in a longitudinal approach by analyzing skin biopsies. Objectives Identification of a gene signature that could be used as a quantitative surrogate marker for the mRSS independent of any treatment. Methods 77 forearm skin biopsies from 32 patients at baseline, and from the same patients after 8 weeks of treatment with SAR100842 (a LPA1 antagonist) or placebo (N=30) and after an additional 16 weeks of treatment with SAR100842 (N=15) in a phase 2 trial, were collected. Total RNA was extracted with the RNeasy® Fibrous Tissue Mini kit according to the manufacturer9s instructions. Total RNA was quantified by spectrofluormetry and qualified by capillary electrophoresis using Agilent Bioanalyzer 2100. Whole transcriptome analysis was performed using Affymetrix chips. Genes highly correlated (Pearson9s correlation) with the mRSS were identified at each treatment visit. A signature was identified as a set of genes whose expression levels correlated consistently either positively or negatively with the mRSS at all study visits regardless of treatment group. The correlation value between the genes and the mRSS at baseline had to be >0.5 or Results This methodology led to the identification of 64 genes considered for the signature and viewed as a single composite marker that was highly correlated to the mRSS. A principal component analysis was computed and the first component explaining the maximum variance in the signature was highly correlated to the mRSS at baseline and week 8. This correlation was confirmed with the median polish algorithm (Pearson9s correlation coefficient of -0.75 and -0.73 respectively). The most significant disease and disorder biological functions associated with the mRSS signature genes were related to immunological diseases. A significant enrichment was also detected for genes associated with inflammatory response and connective tissue disorders with p-values from 2.98E-05 to 2.47E-02. Conclusions An mRSS signature was identified using skin biopsies in SSc patients. Some of these genes (i.e. IRF7, THBS1, COMP or BANK1) have been published using similar approaches in other sets of SSc patients (1), which supports our results. The functional categories of this signature are characteristic for scleroderma pathology reflecting autoimmunity, vasculopathy, inflammation and fibrosis. This mRSS signature needs to be validated in a larger set of SSc patients including assessment of change over time. References Mahoney et al. PLOS Computational Biology 2015: Vol 11; 1–20. Disclosure of Interest I. Agueusop: None declared, S. Illiano: None declared, C. Rocher: None declared, E. Boitier: None declared, J. Murphy: None declared, Y. Allanore Grant/research support from: BMS, Genentech-Roche, Inventiva, Pfizer, sanofi, Consultant for: Actelion, Bayer, Biogen, Genetech-Roche, Galapagos, Medac, Pfizer, Sanofi, Servier, UCB, C. Denton Consultant for: Actelion, Bayer, GSK, CSL Behring, Merck-Serono, Genentech-Roche, Inventiva, Sanofi-Aventis, O. Distler Grant/research support from: Actelion, Bayer, Boehringer Ingelheim, Pfizer, Sanofi, Consultant for: 4 D Science, Actelion, Active Biotec, Bayer, BiogenIdec, BMS, Boehringer Ingelheim, ChemomAb, EpiPharm, espeRare foundation, Genentech/Roche, GSK, Inventiva, Lilly, medac, Mepha, MedImmune, Mitsubishi Tanabe Pharma, Pharmacyclics, Pfizer, Sanofi, Serodapharm, Sinoxa, AbbVie, iQone Healthcare, Mepha, D. Khanna Grant/research support from: Bayer, BMS, Genentech/Roche, Sanofi-Aventis, NIH K24AR063120, Consultant for: Actelion, Bayer, Covis, Cytori, EMD Serono, Genentech/Roche, Gilead, GSK, Sanofi-Aventis, F. Benderitter: None declared

Summary skin tissue dielectric constant (TDC) measurements help assess local skin water to detect incipient early-stage lymphedema subsequent to breast cancer treatment-related lymphedema. However, presurgery measurements are not always obtained and assessments for evolving lymphedema are only made after surgery. Thus, subsequent TDC assessments may be biased in an unknown way dependent on a patient's handedness in relation to the at-risk arm. We investigated this issue by comparing TDC values in dominant and non-dominant volar forearms of 31 left-handed women and 31 right-handed women (age range 24–84 years). Body fat and water percentages were assessed by bioimpedance at 50 KHz. Results showed that TDC values of dominant versus non-dominant arms did not significantly differ for left-handers or for right-handers. There was also no statistically significant difference in absolute TDC values between left- and right-handers or a statistically significant difference in dominant-to-non-dominant arm ratios between left- and right-handers. For the composite data set (N = 62), TDC values for dominant and non-dominant arms were, respectively, 30·0 ± 4·6 and 29·6 ± 4·2 and the dominant-to-non-dominant arm TDC ratio for combined left- and right-handers was 1·015 ± 0·075. These results suggest that handedness is not a major factor when assessing lymphedema status in women who have previously been treated for breast cancer but for whom pretreatment TDCvalues have not been obtained. Moreover, these results suggest that threshold ratios of incipient subclinical unilateral lymphedema based on interarm TDC ratios apply independent of a patient's handedness for the site and tissue depths herein measured.

We investigate the use of skin texture features from the inner forearm as a means for personal identi- fication. The forearm offers a number of potential advantages in that it is a fairly accessible area, and, compared with other zones such as fingertips, is less exposed to the elements and more shielded from wear. We extract and combine skin textural features from two imaging devices (optical and capacitive) with the aim of discriminating between different individuals. Skin texture images from 43 subjects were acquired from three different body parts (back of the hand, forearm and palm); testing used the two sensors either separately or in combination. Skin texture features from the forearm proved effective for discriminating between different individuals with overall recognition accuracy approaching 96%. We found that skin texture features from the forearm are highly individual-specific and therefore suitable for personal identification. Interestingly, forearm skin texture features yielded significantly better accuracy compared to the skin of the back of the hand and of the palm of the same subjects.