Eccrine Sweat Gland Activity Research Articles

Effect of Boron on Sympathetic Skin Response in Rats.

Boron effects on reproduction and growth have been extensively studied in animals. Electrodermal activity (EDA) reflects the activity of eccrine sweat glands stimulated by the release of acetylcholine from sympathetic nerves. In the presen study, it was aimed to examine the effect of boron, which was turned into cream, on sweat glands. A cream form mixed with thyme oil was prepared for EDA recording. Our groups were formed as EDA recording gel (Group 1), cream with thyme oil (Group 2), cream containing 10% boron (Group 3) and cream containing 30% boron (Group 4). In each group, 3 months old, 10 male rats were used, and creams were applied to the soles of the hind extremities of the rats, EDA was recorded from this region after half an hour, and skin conductivity levels (SCL) were recorded as tonic (at rest) and phasic (with auditory sound stimulation). EDA results recorded in the morning were analysed with tonic and phasic recordings. In the morning SCL measurements, tonic SCL value of Group 4 was higher than the other groups (P < 0.001). Although the phasic SCL value was measured, it was significantly higher in Group 4 than in all groups (P < 0.0s). EDA measurements showed that boron increased sweat gland activity by increasing sympathetic nerve activity.

Separate extraction of human eccrine sweat gland activity and peripheral hemodynamics from high- and low-quality thermal imaging data

Sweat gland activity and peripheral hemodynamics, which characterize the function of sympathetic cholinergic nerve fibers and the manifestation mechanisms of vascular tone regulation, respectively, can be detected via dynamic thermography of the skin. Thus, they are useful parameters for diagnosing various forms of neuropathy and functional circulatory disorders. Both parameters affect the dynamics of the skin temperature; therefore, for an adequate description of thermographic data, it is necessary to build models that consider both these coexisting components simultaneously. PurposeThe objective of this study was to determine the spatiotemporal and statistical features of dynamic thermograms of skin areas with sweat glands and to develop methods for the extraction of temperature components mediated by sweat gland activity (Tsweat) separately from hemodynamics (Tblood) based on thermograms of high and low temperature resolutions. MethodsTo separate the Tsweat and Tblood components, simultaneous thermographic and photoplethysmographic (PPG) measurements were performed in the area of the fingers during a deep inspiratory gasp (DIG). PPG data, which were obtained solely by hemodynamics, were converted into a temperature signal (Tblood) using the spectral filtering approach. By calculating the difference between the skin (Tskin) and blood (Tblood) temperature components, the Tsweat component was determined, which characterizes sweat gland activity and the integrity of the cholinergic sympathetic nerve fibers that innervate them. The Tsweat component was compared with the active sweat pore count curve, which was determined by the adaptive detection of local temperature minima. Thermographic and PPG measurements were performed for 3 min on a group of 15 volunteers during the DIG test. The skin temperature was measured using a cooled thermal imaging camera in the spectral range of 8–9 μm with a temperature sensitivity of 0.02 °C. PPG measurements were performed using a reflectance sensor with a central wavelength of 800 nm. Wavelet analysis with the Morlet basis function was used to preliminarily determine the spectrum of spontaneous temperature oscillations in an area of the skin with and without sweat pores. Statistical parameters of the histogram, such as the standard deviation and the statistical pore activation index (SPAI) - which is proposed in this paper were used in the DIG test to detect sweat gland activity with low-temperature resolution thermograms. The temporal dynamics of the statistical parameters were compared with the dynamics of the sweat pore count. ResultsThe Tsweat component was correlated with the sweat pore count on the thermogram with a coefficient of 0.75, confirming the dependence of this temperature component on the sweat gland activity and the need for considering this activity in the analysis of the spatiotemporal dynamics of the human skin temperature. The use of the proposed SPAI and standard deviation allows the detection of sweat gland activity even with thermograms of a low temperature resolution. The use of an integrated map of the sweat gland activity will help the specialist to assess the degree of integrity of the innervation of skin areas in a single image. The primary assessment of the spectrum of temperature oscillations at rest indicated that spontaneous sweat gland activity is accompanied by high-frequency oscillations in the skin temperature localized in the area of sweat pores, within the frequency range of 0.07–0.3 Hz. This suggests the possibility of spectral separation of the temperature component mediated by sweat gland activity from the hemodynamic component, which dominates in the region of <0.1 Hz. The proposed two-component approach for the analysis of skin temperature dynamics allows separate assessment of sympathetic innervation and rhythms of hemodynamic regulation using dynamic thermograms.

A Flexible and Printable Chemiresistor Sensor Array for Detection and Recognition of Aging-Associated Human Body Odor

Introduction Human skin emits a variety of volatile organic compounds that are perceived as unique body odor [1]. It has been believed human body odor contains a large amount of information related to body chemistry of individuals. During recent years, there has been great interest in aging-associated body odors since some compounds have been identified existing in specific age groups [2]. For example, diacetyl has been found is a key contributor for middle-aged male odor [3]. 2-nonenal has been detected only in people over the age of 40 (old person smell) [4]. Organic acids (such as hexanoic acid and its derivatives) are characteristic odor of young ages due to their active activity of eccrine sweat glands [2]. The detection and recognition of aging-associated body odor may suggest many potential applications. However, the assessment of body odor at present mainly depends on human panelist and lack of effective sensing approaches. In this work, a flexible and printable chemiresistor sensor is developed for the detection and recognition of aging-associated odor compounds. The fabrication process of the sensor, the selection method of sensitive materials, and the pattern recognition of an optimized sensor array on three typical odor substances (hexanoic acid, diacetyl and 2-nonenal) are introduced. Materials and Method The chemiresistor sensor was prepared by using conductive composites of carbon black (CB) with various sensing materials. Many materials have been reported that can be used in the fabrication of CB-based chemiresistor sensors including polymers, lipopolymers, low volatility organic molecules, intrinsic conducting polymers, gas chromatography stationary materials, and so on. How to select those materials that are suitable for the sensing of body odor is a problem. In this work we investigated and compared the performance of about fifty materials commercially available. The chemiresistor sensors were prepared by mixing CB and the sensitive materials in tetrahydrofuran (or chloroform) with appropriate critical concentrations. Interdigitated array (IDA) electrode was prepared by a commercial inkjet printer using Ag conductive ink and polyethylene terephthalate (PET) film. The CB suspensions of different sensing materials were dropcast automatically by a digital dispenser on the IDA electrode to fabricate the array sensors. The performance of the sensitive materials was evaluated by their response on five McReynolds test probes (benzene, 1-butanol, 2-pentanone, nitropropane and pyridine). The selectivity of sensor channels were analysis by principle component analysis (PCA) as well as multivariate analysis of covariance (MANCOVA). A 6-channel sensor array optimized according to F-values of Wilk’s Λ statistic was used for pattern recognition of hexanoic acid, diacetyl and 2-nonenal. Vapors with standard concentration (from several ppm to several tens of ppm) were generated by a calibration gas generation system (GASTEC, Japan). The response of chemresistor sensor was recorded by a home-made multiple channel sensing device and control software system. Results and Conclusions Figure 1 shows the illustrated experimental setup used for the generation and sensing of odor samples with standard concentrations. The flexible IDA electrode with 8 channels basically was prepared by a low cost inkjet printing process. The McReynolds probe compounds are generally used in gas chromatography to assess the separation capability of gas chromatography stationary phase. Here we use them as a reference to select the sensitive materials for the fabrication of sensor array. Figure 2a shows the response characteristics of twenty-four materials on the five McReynolds probes (The details of these materials was not disclosed in view of business consideration). Figure 2b shows the ordered F-value of the above 24 materials by analysis of MANCOVA. A large F-value means that the variable has high selectivity [5]. That is to say, the materials holds high discrimination ability in the array. The chemiresistor sensor array can be then optimized by comprehensive consideration both the selectivity (F-value) and sensitivity (response intensity over 5 ‰). For example, the red mark in figure 2b lists an optimized sensor array including 6 channels ( No.13, 34, 32, 20, 23 and 16). Figure 3 shows the PCA result of the optimized sensor array on the McReynolds probes. The five compounds are well separated in the PCA plot which demonstrates that the optimized sensor array may exhibit a broad range of ability to discriminate odorant molecules. This result provides us a guiding principle to design sensor arrays for different sensing targets. The sensor array is then used for sensing of hexanoic acid, diacetyl and 2-nonenal. The PCA plot shown in figure 4 demonstrates that it succeeds in the detection and recognition of aging-associated human body odors. Considering the excellent body odor sensing performance as well as printable and flexible characteristics, it is promising that the chemiresistor sensor array can be further developed as a wearable device and applied for body odor-related biomedical and health application.

Sparse Deconvolution of Electrodermal Activity via Continuous-Time System Identification.

Electrodermal activity (EDA) indicates different eccrine sweat gland activity caused by the stimulation of the autonomic nervous system. Recovering the number, timings, and amplitudes of underlying neural stimuli and physiological system parameters from the EDA is a challenging problem. One of the challenges with the existing methods is the non-convexity of the optimization formulations for estimating the parameters given the stimuli. We solve this parameter estimation problem using the following continuous-time system identification framework: 1) we specifically use the Hartley modulating function (HMF) for parameter estimation so that the optimization formulation for estimating the parameters given the stimuli is convex; and 2) we use Kaiser windows with different shape parameters to put more emphasis on the significant spectral components so that there is a balance between filtering out the noise and capturing the data. We apply this algorithm to skin conductance (SC) data, a measure of EDA, collected during cognitive stress experiments. Under a sparsity constraint, in the HMF domain, we successfully deconvolve the SC signal. We obtain number, timings, and amplitudes of the underlying neural stimuli along with the system parameters with R2 above 0.915. Moreover, using simulated data, we illustrate that our approach outperforms the existing EDA data analysis methods, in recovering underlying stimuli. We develop a novel approach for deconvolution of SC by employing the HMF method and capturing the significant spectral components of SC data. Recovering the underlying neural stimuli more accurately using this approach will potentially improve tracking emotional states in affective computing.

Skin Capacitance Mapping of Eccrine Sweat Gland Activity during Pregnancy

Skin capacitance mapping is a real-time non-invasive method useful in the assessment of eccrine gland activity. We presently revisit and explore the sweat gland production in pregnant women. Sprouts of sweat vapour are progressively increased during pregnancy by recruiting increasing numbers of active sweat pores. An overall moisturization of the stratum corneum ensues in absence of increased liquid sweat production. These aspects are conveniently assessed using skin capacitance mapping. The sweat duct opening could represent an increased way for percutaneous penetration of some xenobiotics during pregnancy.

A non-contact technique for measuring eccrine sweat gland activity using passive thermal imaging

An approach for monitoring eccrine sweat gland activity using high resolution Mid-Wave Infrared (MWIR) imaging (3–5μm wave band) is described. This technique is non-contact, passive, and provides high temporal and spatial resolution. Pore activity was monitored on the face and on the volar surfaces of the distal and medial phalanges of the index and middle fingers while participants performed a series of six deep inhalation and exhalation exercises. Two metrics called the Pore Activation Index (PAI) and Pore Count (PC) were defined as size-weighted and unweighted measures of active sweat gland counts respectively. PAI transient responses on the finger tips were found to be positively correlated to Skin Conductance Responses (SCRs). PAI responses were also observed on the face, although the finger sites appeared to be more responsive. Results indicate that thermal imaging of the pore response may provide a useful, non-contact, correlate measure for electrodermal responses recorded from related sites.

Immunohistochemical sweat gland profiles

Human sweat glands are heterogeneous in their structures and functions. Accordingly, eccrine, apocrine, and apoeccrine glands are distinguished. Some immunohistochemical markers are expected to distinguish the sweat gland types in their secretory and excretory parts. This study used two sets of antibodies. The first panel was composed of antibodies directed to well-defined sweat gland structures. The molecular targets included the low-molecular-weight cytokeratins CAM 5.2, the S100-B protein, the epithelial membrane antigen (EMA), the carcinoembryonic antigen (CEA), and the lectin Ulex europaeus agglutinin-1 (UEA-1). A second exploratory panel of antibodies targeted syndecan-1 (CD138), NKI-C3 (CD63), and CD68. They were used to disclose some undescribed antigen expressions in human sweat glands. The first set of antibodies confirmed previous findings. The immunoreactivities of the three sweat gland types were similar in the excretory ducts. By contrast, they were distinguished in the deeper coiled secretory portions of the glands. Clues supporting their distinction and probably their functional activity were obtained by immunohistochemistry using the S100-B protein, CEA and CD63 antibodies. The immunoreactivity to the S100-B protein, CEA and CD63 possibly help identifying apoeccrine sweat glands or a peculiar functional activity of eccrine sweat glands.

Antiperspirantien bei der Behandlung der fokalen Hyperhidrose

In Europe often no clear distinction is made between deodorant and antiperspirant. Particularly in Germany, the labeling "deo" is used for both. Only antiperspirants are capable of influencing the activity of eccrine sweat glands. In the treatment of focal hyperhidrosis, the use of aluminum chloride solutions represents the first choice. The efficacy is well documented in a variety of studies. Subjective side effects include pruritus and - less often - irritant dermatitis, which can be treated symptomatically and usually does not require discontinuation of the treatment. Rare variants of focal hyperhidrosis like auriculotemporal syndrome, Ross syndrome and nevus sudoriferus also are suitable for treatment with topical aluminum chloride hexahydrate solutions.

Electrochemical Characterization of Nickel Electrodes in Phosphate and Carbonate Electrolytes in View of Assessing a Medical Diagnostic Device for the Detection of Early Diabetes

AbstractIn view of optimizing a multi‐electrode device using proprietary technology for noninvasive assessment of eccrine sweat gland activity and thus the early detection of diabetes, we thoroughly explored the electrochemical behavior of a nickel electrode in a three‐electrode set up combining a nickel counter electrode and a nickel pseudo‐reference electrode in synthetic buffered phosphate and carbonate solutions in presence of chloride, lactate and urea that mimic the composition of physiological sweat. This approach provides insight into the origin of the onset of responses measured upon the application of low voltage potential with variable amplitudes to Ni electrodes on the skin. For low voltage amplitude of ca. ΔE=0.6 V, the electrochemical reactions measured at the electrodes are those related to the oxidation of Ni leading to the formation of a passive layer, as well as the reduction of this passive layer. For voltage amplitude higher than 1 V, or current densities higher than 1 mA/cm2, the breakdown of the passive layer becomes the main electrochemical anodic reaction, while its reduction and the electrolytic solution govern the cathode reactions. This brings explanation of the nonlinear current‐voltage features measured during the clinic tests. Finally, the obtained results make possible the definition of the experimental electrochemical conditions where the Ni electrodes can be renewed.

S6.5 Mental sweating: A reliable autonomic marker of emotional arousal

Autonomic indices are relevant markers classically used to evaluate the somatic impact of emotional processing. In this frame, the electrical activity of eccrine sweat glands, usually recorded as skin conductance (SC), is a very wide-used activity allowing to index orientation behavior, motor activity, cognitive processes or emotional states. Although fMRI-proof SC recording systems exist, introducing metallic device, such as SC electrodes, could sometimes cause severe injuries like third degree burns.

PAR-2 receptor-induced effects on human eccrine sweat gland cells

Serine proteases can induce cell signaling by stimulating G-protein-coupled receptors, called proteinase-activated receptors (PAR's) on a variety of epithelial cells. While PAR-2, one such receptor, activates cell signaling in a secretory cell line derived from human sweat glands, there was no information on their presence and effects on intact sweat glands. PAR-2 presence and activation of eccrine sweat glands isolated from human skin samples was investigated using Western blot analysis, immunohistochemistry, electron microscopy (EM) and Ca(2+) imaging. Anti-human PAR-2 antibody demonstrated the presence of these receptors in eccrine sweat glands. EM showed that PAR-2 activation resulted in degranulation of secretory cells. Ca(2+) imaging using PAR-2 activators demonstrated a two phase increase in [Ca(2+)](i) which was dependent on extracellular Ca(2+) for the second phase, and that the response could be blocked by prior incubation with xestospongin, the IP(3) receptor blocker. The results demonstrated that PAR-2 receptors are present in human sweat gland secretory cells and that these receptors are functionally active and can induce changes associated with secretory events in eccrine glands.

Changes in cholinergic sweat gland activation in diabetic neuropathy identified by computerised sweatspot analysis

Peripheral small-fibre denervation has been reported to result in decreased activation of eccrine sweat glands to muscarinic cholinergic agents. Using computerised image-analysis of pilocarpine-activated sweatspot prints of a 4 cm2 area of the dorsum of the foot in 79 randomly selected diabetic patients we have identified a group of neuropathic patients (18%) with decreased sweatspot activation (less than 20/cm2), and a smaller group (6%) of younger patients with less marked neuropathy who had increased activation (greater than 132/cm2), probably resulting from denervation supersensitivity. The associations between sweatspot density and other conventional tests of peripheral nerve function were weak. The prevalence of abnormal sweatspot density, 24%, was similar to that of other tests, except thermal thresholds at the feet (35-37%), which were not correlated with sweatspot activation, suggesting that diabetic neuropathy has differing effects on afferent and efferent small fibres. The method is rapid and reproducible (median coefficient of variation 14%) and its ability to identify patients with increased, as well as decreased, peripheral nerve function may be of value in the characterisation and longitudinal follow-up of small-fibre abnormalities in diabetes.

Epidermal thermal conductivity and stratum corneum hydration in cat footpad.

Epidermal thermal conductivity (k) was calculated for the cat footpad by measuringtransepidermal heat flux and temperature gradient (¿T) while changes in stratum corneum water content were produced by "internal hydration" (IH; eccrine sweat gland activity by nerve stimulation) or by "external hydration" (HH; exposure to air saturated with water vapor). In some experiments, cutaneous vasoconstriction accompanying IH was prevented by an alpha-adrenergic receptor blocking agent, phenoxybenzamine (POB), 3.52 mg/kg iv. For dry skin k=0.167 plus or minus 0.023 (SE) W.m (-1) degree C (-1). With and without POB, IH produced 49.5% and 17.2% increases in k, respectively; HH after IH did not increase k more. With POB, IH increased k more than did HH alone (49.5% and 15.5%, respectively) and at a higher rate (4.22 times 10 minus 3 and 0.63 times 10 minus 3 W.m minus 1.degree C minus 1. min minus 1, respectively.) As k increased, usually deltaT decreased. Increasing k and decreasing deltaT with skin hydration explain the phenominon that air temperature is felt to be lower the more humid a cold exposure, since the temperature of thermoreceptors at the dermoepidermal junction is closer to that of the skin surface when the corneum is hydrated than when it has a low water content.

Cutaneous vascular responses of dehydrated men following ingestion of saline or water.

SummaryIn 3 dehydrated male subjects, ingestion of water and saline were equally effective at triggering immediate increases in sweating. Sustained increases in cutaneous volume opacity pulse amplitudes were observed only after water ingestion. Since both saline and water ingestion induced increased sweating while cutaneous vasodilatation only occurred after water intake, support was indicated for the concept that dilatation of the cutaneous vascular bed is independent of the activity of eccrine sweat glands.

Modification of skin mechanical properties by eccrine sweat gland activity.

ArticleModification of skin mechanical properties by eccrine sweat gland activity.T Adams, and W S HunterT Adams, and W S HunterPublished Online:01 Apr 1969https://doi.org/10.1152/jappl.1969.26.4.417MoreSectionsPDF (723 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByAnatomy of the sense of touch in sea otters: Cutaneous mechanoreceptors and structural features of glabrous skin23 August 2021 | The Anatomical Record, Vol. 305, No. 3The Body and the Brain: Measuring Skin Conductance Responses to Understand the Emotional Experience8 December 2016 | Organizational Research Methods, Vol. 22, No. 1Heat Stress17 August 2012Principles of Electrodermal Phenomena22 September 2011Fingertip Moisture Is Optimally Modulated During Object ManipulationT. André, P. Lefèvre, and J-L. Thonnard1 January 2010 | Journal of Neurophysiology, Vol. 103, No. 1Heat Stress16 April 2001Neural Control of Electrodermal Activity: Spinal and Reticular MechanismsInvestigations on the biomechanical significance of dermatoglyphic ridgesEvolutionary origins of the mammary glandMammal Review, Vol. 21, No. 2Histochemical aspects of stratum corneum function in the feline foot padArchives of Dermatological Research, Vol. 281, No. 8Is Mediation of Sweating Cholinergic, Adrenergic, or Both? A Comment on the LiteraturePsychophysiology, Vol. 24, No. 3Epidermal water and electrolyte content and the thermal, electrical and mechanical properties of skinLateralization in the Electrodermal System as a Function of Cognitive/Hemispheric ManipulationsPsychophysiology, Vol. 16, No. 2NEUROENDOCRINE CONTROL OF SWEAT GLANDSJournal of Investigative Dermatology, Vol. 69, No. 1Neural and Humoral Control of Apocrine GlandsJournal of Investigative Dermatology, Vol. 63, No. 1Electrodermal Recovery Rate, Goal-Orientation, and AversionPsychophysiology, Vol. 9, No. 5CARNIVORESTransepidermal Water Loss of Human NewbornsJournal of Investigative Dermatology, Vol. 54, No. 6 More from this issue > Volume 26Issue 4April 1969Pages 417-9 https://doi.org/10.1152/jappl.1969.26.4.417PubMed5775326History Published online 1 April 1969 Published in print 1 April 1969 Metrics

Eccrine sweat gland activity during the menstrual cycle.

Eccrine sweat gland activity during the menstrual cycle.

Characteristics of eccrine sweat gland activity in the footpad of the cat.

Characteristics of eccrine sweat gland activity in the footpad of the cat.

Eccrine sweat gland activity in heat acclimation.

The response of eccrine sweat glands of the forearms of four females was investigated during acclimation to heat. The sweat rate increased progressively during ten exposures. There was no significant change in the number of active sweat glands. The increased sweat rate could, therefore, be attributed to enhanced secretory activity of individual glands.

Human eccrine sweat gland activity and palmar electrical skin resistance.

Sweat gland activity, monitored as a function of the rate at which water vapor was removed from the skin surface (EWL), was measured simultaneously with electrical skin resistance (ESR) from adjacent 1-cm2 areas on the human palm. Both ESR and EWL, and Delta ESR and Delta EWL, were correlated throughout 20–30 min of testing during which the subject rested or participated in conversation. The ratio Delta ESR/Delta EWL was greater the lower the EWL level. As EWL approached diffusion levels (0.06 mg/min.cm2), ESR assumed the highest and most stable value (ca. 170 kilohms). Subject differences in ESR at high EWL rates and the pattern of ESR-EWL relationships through the range of sudomotor activity (0.06–0.18 mg/min.cm2) are attributed to individual variation in the density and activity of sweat glands on the palmar surface. The character of ESR-EWL correspondence was also seen to vary with the phase of sweating activity for any one subject. evaporative water loss; physiological testing; galvanic skin reflex; psychological testing; psychogalvanic reflex; sweat measurement Submitted on October 22, 1964

Eccrine sweat gland activity and racial differences in resting skin conductance.

ABSTRACTActive eccrine sweat gland activity was measured in 30 Negro and 29 Caucasian male subjects to determine whether sweat gland activity was a possible factor in racial differences in skin conductance. Basal skin conductance, heart rate, respiratory rate, finger skin temperature and blood pressure were also obtained. Negro Ss had significantly lower skin conductance but no other significant physiological differences were found. While there was no significant difference in number of active sweat glands between the races, the intragroup relationship between sweat gland count and skin conductance was significantly higher for the Negro Ss. The two groups did not differ in number of nonspecific galvanic skin responses (GSRs) but the Caucasian Ss showed greater change in skin conductance to an initial tone stimulus. When differences in prestimulus levels were taken into account, the group differences in response to stimuli were no longer significant.