Store-operated Ca2+ entry regulates Ca2+-activated chloride channels and eccrine sweat gland function

PubMed Central

Concepcion, Axel R.; Vaeth, Martin; Wagner, Larry E.; Eckstein, Miriam; Hecht, Lee; Yang, Jun; Crottes, David; Seidl, Maximilian; Shin, Hyosup P.; Weidinger, Carl; Cameron, Scott; Turvey, Stuart E.; Issekutz, Thomas; Meyts, Isabelle; Lacruz, Rodrigo S.; Cuk, Mario; Yule, David I.

2016-01-01

Eccrine sweat glands are essential for sweating and thermoregulation in humans. Loss-of-function mutations in the Ca2+ release–activated Ca2+ (CRAC) channel genes ORAI1 and STIM1 abolish store-operated Ca2+ entry (SOCE), and patients with these CRAC channel mutations suffer from anhidrosis and hyperthermia at high ambient temperatures. Here we have shown that CRAC channel–deficient patients and mice with ectodermal tissue–specific deletion of Orai1 (Orai1K14Cre) or Stim1 and Stim2 (Stim1/2K14Cre) failed to sweat despite normal sweat gland development. SOCE was absent in agonist-stimulated sweat glands from Orai1K14Cre and Stim1/2K14Cre mice and human sweat gland cells lacking ORAI1 or STIM1 expression. In Orai1K14Cre mice, abolishment of SOCE was associated with impaired chloride secretion by primary murine sweat glands. In human sweat gland cells, SOCE mediated by ORAI1 was necessary for agonist-induced chloride secretion and activation of the Ca2+-activated chloride channel (CaCC) anoctamin 1 (ANO1, also known as TMEM16A). By contrast, expression of TMEM16A, the water channel aquaporin 5 (AQP5), and other regulators of sweat gland function was normal in the absence of SOCE. Our findings demonstrate that Ca2+ influx via store-operated CRAC channels is essential for CaCC activation, chloride secretion, and sweat production in humans and mice. PMID:27721237

Lack of harmonization in sweat testing for cystic fibrosis - a national survey.

PubMed

Christiansen, Anne Lindegaard; Nybo, Mads

2014-11-01

Sweat testing is used in the diagnosis of cystic fibrosis. Interpretation of the sweat test depends, however, on the method performed since conductivity, osmolality and chloride concentration all can be measured as part of a sweat test. The aim of this study was to investigate how performance of the test is organized in Denmark. Departments conducting the sweat test were contacted and interviewed following a premade questionnaire. They were asked about methods performed, applied NPU (Nomenclature for Properties and Units) code, reference interval, recommended interpretation and referred literature. 14 departments performed the sweat test. One department measured chloride and sodium concentration, while 13 departments measured conductivity. One department used a non-existing NPU code, two departments applied NPU codes inconsistent with the method performed, four departments applied no NPU code and seven applied a correct NPU code. Ten of the departments measuring conductivity applied reference intervals. Nine departments measuring conductivity had recommendations of a normal area, a grey zone and a pathological value, while four departments only applied a normal and grey zone or a pathological value. Cut-off values for normal, grey and pathological areas were like the reference intervals inconsistent. There is inconsistent use of NPU codes, reference intervals and interpretation of sweat conductivity used in the process of diagnosing cystic fibrosis. Because diagnosing cystic fibrosis is a combined effort between local pediatric departments, biochemical and genetic departments and cystic fibrosis centers, a national harmonization is necessary to assure correct clinical use.

Biochemical changes in sweat following prolonged ischemia.

PubMed

Ferguson-Pell, M; Hagisawa, S

1988-01-01

Much emphasis has been placed on the measurement of physical parameters at the body support interface in order to detect and moderate conditions which could result in pressure damage to soft tissues. Major difficulties are encountered both in the design of instrumentation and interpretation of the data collected. Metabolic processes in sweat glands that control sweat secretion have been shown to be sensitive to applied pressure, producing sweating rate suppression and changes in sweat NaCl concentration. In this study, we have demonstrated the feasibility of measuring lactate concentration in sweat collected locally using an electrochemical stimulation technique (iontophoresis of pilocarpine nitrate). Elevated levels of sweat lactate concentration during local tissue indentation were detected in a group of able-bodied subjects. Upon removal of the indentor, however, levels of sweat lactate returned to normal.

Radiofrequency Thermotherapy for Treating Axillary Hyperhidrosis.

PubMed

Schick, Christoph H; Grallath, Tanja; Schick, Kerstin S; Hashmonai, Moshe

2016-05-01

Thermotherapy has been established between conservative and surgical options as a minimally invasive method for the treatment of axillary hyperhidrosis. The objective of this study was to present radiofrequency thermotherapy (RFTT) as a safe and effective new treatment method. Thirty adult patients with pronounced axillary hyperhidrosis were treated with RFTT with noninsulated microneedles 3 times at intervals of 6 weeks. Subjective improvement was rated using the Hyperhidrosis Disease Severity Scale (HDSS) and Dermatology Life Quality Index (DLQI). Satisfaction and estimated reduction of sweating were monitored. Objective measurements were made using gravimetry. Adverse effects were recorded in follow-up. At the 6-month follow-up, improvement in sweating was seen in 27 patients. The HDSS dropped from 3.4 to 2.1, the DLQI improved significantly from 16 to 7. The gravimetric measurements of sweat were reduced from 221 to 33 mg/min. The average reduction of sweating was reported to be 72%. Adverse effects were generally mild and improved rapidly. Radiofrequency thermotherapy was shown to be an effective and minimally invasive treatment option for axillary hyperhidrosis. Patients described their sweating as normal. The method clearly has the potential to normalize axillary sweating.

Feasibility and normal values of an integrated conductivity (Nanoduct™) sweat test system in healthy newborns.

PubMed

Kuehni, Claudia E; Schindler, Matthias; Mazur, Agnieszka; Malzacher, Andreas; Hornung, René; Barben, Juerg

2017-07-01

Nanoduct™ is a simple and practical sweat analysis system measuring conductivity in situ. It requires only three microlitres of sweat, making it especially applicable to newborns. We measured conductivity in 260 healthy term infants at the age of four days, and again at four weeks to determine the proportion of successful tests, test duration, and normal values for sweat conductivity in newborns. Sufficient sweat was collected in 159/260 of four-day olds (61%), and in 225/239 of four-week olds (94%). Mean (sd) test duration was 27 (5) and 25 (5) min. Mean (sd, range) conductivity was 53mmol/l (16, 8-114) at age four days, and 36 (9, 12-64) at four weeks. Determination of sweat conductivity using Nanoduct™ cannot be recommended for four-day old newborns. However, at the age of four weeks the success rate is high (94%), and conductivity values at that age are comparable to older healthy children. Copyright © 2017 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Endoscopic thoracic sympathectomy

MedlinePlus

Endoscopic thoracic sympathectomy (ETS) is surgery to treat sweating that is much heavier than normal. This condition ... hyperhidrosis . Usually the surgery is used to treat sweating in the palms or face. The sympathetic nerves ...

[Study on sweat gland regeneration induced by microenvironment of three-dimensional bioprinting].

PubMed

Yao, B; Xie, J F; Huang, S; Fu, X B

2017-01-20

Sweat glands are abundant in the body surface and essential for thermoregulation. Sweat glands fail to conduct self-repair in patients with large area of burn and trauma, and the body temperature of patients increases in hot climate, which may cause shock or even death. Now, co-culture system, reprogramming, and tissue engineering have made progresses in inducing sweat gland regeneration, but the inductive efficiency and duration need to be improved. Cellular microenvironment can regulate cell biological behavior, including cell migration and cell differentiation. This article reviews the studies of establishment of microenvironment in vitro by three-dimensional bioprinting technology to induce sweat gland regeneration.

Sweat Chloride as A Biomarker of CFTR Activity: Proof of Concept and Ivacaftor Clinical Trial Data

PubMed Central

Accurso, Frank J.; Van Goor, Fredrick; Zha, Jiuhong; Stone, Anne J.; Dong, Qunming; Ordonez, Claudia L.; Rowe, Steven M.; Clancy, John Paul; Konstan, Michael W.; Hoch, Heather E.; Heltshe, Sonya L.; Ramsey, Bonnie W.; Campbell, Preston W.; Ashlock, Melissa A.

2014-01-01

Background We examined data from a Phase 2 trial {NCT00457821 } of ivacaftor, a CFTR potentiator, in cystic fibrosis (CF) patients with a G551D mutation to evaluate standardized approaches to sweat chloride measurement and to explore the use of sweat chloride and nasal potential difference (NPD) to estimate CFTR activity. Methods Sweat chloride and NPD were secondary endpoints in this placebo-controlled, multicenter trial. Standardization of sweat collection, processing, and analysis was employed for the first time.. Sweat chloride and chloride ion transport (NPD) were integrated into a model of CFTR activity. Results Within-patient sweat chloride determinations showed sufficient precision to detect differences between dose-groups and assess ivacaftor treatment effects. Analysis of changes in sweat chloride and NPD demonstrated that patients treated with ivacaftor achieved CFTR activity equivalent to approximately 35%–40% of normal. Conclusions Sweat chloride is useful in multicenter trials as a biomarker of CFTR activity and to test the effect of CFTR potentiators. PMID:24660233

Sweat chloride as a biomarker of CFTR activity: proof of concept and ivacaftor clinical trial data.

PubMed

Accurso, Frank J; Van Goor, Fredrick; Zha, Jiuhong; Stone, Anne J; Dong, Qunming; Ordonez, Claudia L; Rowe, Steven M; Clancy, John Paul; Konstan, Michael W; Hoch, Heather E; Heltshe, Sonya L; Ramsey, Bonnie W; Campbell, Preston W; Ashlock, Melissa A

2014-03-01

We examined data from a Phase 2 trial {NCT00457821} of ivacaftor, a CFTR potentiator, in cystic fibrosis (CF) patients with aG551D mutation to evaluate standardized approaches to sweat chloride measurement and to explore the use of sweat chloride and nasal potential difference (NPD) to estimate CFTR activity. Sweat chloride and NPD were secondary endpoints in this placebo-controlled, multicenter trial. Standardization of sweat collection, processing,and analysis was employed for the first time. Sweat chloride and chloride ion transport (NPD) were integrated into a model of CFTR activity. Within-patient sweat chloride determinations showed sufficient precision to detect differences between dose-groups and assess ivacaftor treatment effects. Analysis of changes in sweat chloride and NPD demonstrated that patients treated with ivacaftor achieved CFTR activity equivalent to approximately 35%–40% of normal. Sweat chloride is useful in multicenter trials as a biomarker of CFTR activity and to test the effect of CFTR potentiators.

Gay theatre, AIDS, and taboo: reconsidering Robert Chesley.

PubMed

Gavrila, Rebecca

2013-01-01

Theatre was among the first popular culture forms to address HIV/AIDS and did so memorably in such works as The Normal Heart, As Is, Love! Valor! Compassion!, and March of the Falsettos. As a response to criticisms of stage dramas focusing on HIV/AIDS in the main as undifferentiated and melodramatic, the author suggests critical consideration of two works by playwright Robert Chesley. In her analysis of Night Sweats and Jerker, the author argues Chesley offers an alternative perspective that is both liberatory and sex-positive.

Somatostatin receptors are strongly expressed in palmoplantar sweat glands and ducts: studies of normal and palmoplantar pustulosis skin.

PubMed

Hagforsen, E; Michaëlsson, G; Stridsberg, M

2011-07-01

The acrosyringium is the target for inflammation in the chronic and intensely inflammatory skin disease palmoplantar pustulosis (PPP). The sweat-gland apparatus seems to be an immunocompetent structure that probably contributes to skin defence. Furthermore, the sweat gland and duct may be a hitherto unrecognized neuroendocrine organ. To obtain further information about the neuroendocrine properties of the sweat-gland apparatus by examining expression of the somatostatin receptors (SSTRs) 1-5 in healthy palmar skin and in PPP skin. Biopsy specimens were taken from 25 patients with PPP and 25 healthy controls. Immunohistochemical analysis was used to investigate expression of SSTRs 1-5. SSTRs 1-5 were expressed in both epidermal and endothelial structures. The staining intensity of the sweat-gland apparatus was more pronounced than that of the epidermis. Expression differed significantly between lesional PPP and normal plantar skin, with increased expression of SSTRs 3 and 4 in ducts in epidermis, and decreased expression of SSTR 1 in ducts in both papillary and reticular dermis. In specimens with pronounced inflammation, numerous dendritic cells with strong expression of SSTRs 1, 2 and 4 were seen, especially in the papillary dermis. The presence of SSTRs in palmoplantar skin, and specifically at high density in the sweat glands and ducts, might be of particular importance in skin neuroimmunoendocrinology. Although the relevance of the changes in SSTR expression in PPP skin compared with normal skin is unclear, our hypothesis is that these differences might influence the function of both the neuroendocrine and neuroimmunological properties of palmoplantar skin, especially in the sweat-gland apparatus. © The Author(s). CED © 2011 British Association of Dermatologists.

Sweat, the driving force behind normal skin: an emerging perspective on functional biology and regulatory mechanisms.

PubMed

Murota, Hiroyuki; Matsui, Saki; Ono, Emi; Kijima, Akiko; Kikuta, Junichi; Ishii, Masaru; Katayama, Ichiro

2015-01-01

The various symptoms associated with excessive or insufficient perspiration can significantly reduce a patient's quality of life. If a versatile and minimally invasive method could be established for returning sweat activity to normalcy, there is no question that it could be used in the treatment of many diseases that are believed to involve perspiration. For this reason, based on an understanding of the sweat-gland control function and sweat activity, it was necessary to conduct a comprehensive search for the factors that control sweating, such as the central and peripheral nerves that control sweat-gland function, the microenvironment surrounding the sweat glands, and lifestyle. We focused on the mechanism by which atopic dermatitis leads to hypohidrosis and confirmed that histamine inhibits acetylcholinergic sweating. Acetylcholine promotes the phosphorylation of glycogen synthesis kinase 3β (GSK3β) in the sweat-gland secretory cells and leads to sensible perspiration. By suppressing the phosphorylation of GSK3β, histamine inhibits the movement of sweat from the sweat-gland secretory cells through the sweat ducts, which could presumably be demonstrated by dynamic observations of the sweat glands using two-photon microscopy. It is expected that the discovery of new factors that control sweat-gland function can contribute to the treatment of diseases associated with dyshidrosis. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

CROSS CULTURAL ANALYSIS OF DETERMINANTS OF HOT FLASHES AND NIGHT SWEATS: LATIN-AMERICAN IMMIGRANTS TO MADRID AND THEIR SPANISH NEIGHBORS

PubMed Central

Pérez-Alcalá, Irene; Sievert, Lynnette Leidy; Obermeyer, Carla Makhlouf; Reher, David Sven

2013-01-01

Objective This study applies a biocultural perspective to better understand the determinants of hot flashes and night sweats within immigrant and local populations in Madrid, Spain. Methods A combined sample of 575 women from Madrid, aged 45 to 55, was drawn from two studies. The Spanish sample (n=274) participated in the Decisions at Menopause Study (DAMES) in 2000–2002. The Latin-American sample (n=301) was drawn from immigrants to Madrid in 2010–2011. Chi square analyses and logistic regression models were carried out among the combined controlling by origin of provenance. Results Forty four percent of the women reported hot flashes, 36% reported night sweats and 26% both symptoms. Compared to Spanish women, Latin-American women were less likely to report hot flashes (OR 0.7, 95% CI 0.4–0.9) after controlling for demographic variables and menopausal status. The same was not found for night sweats and for both symptoms combined. Determinants of hot flashes differed from determinants of night sweats. Conclusions Because determinants differed, hot flashes and night sweats should be queried and analyzed separately. Latin-American women were less likely to report hot flashes, but not night sweats or both symptoms combined. More research is needed to clarify the differences in reported hot flashes as the lesser report among immigrants could have been a cultural rather than a biological phenomenon. PMID:23571525

Abnormal sudomotor function in the hypomelanotic macules of tuberous sclerosis complex.

PubMed

Chudnow, R S; Wolfe, G I; Sparagana, S P; Delgado, M R; Batchelor, L; Roach, E S

2000-08-01

To investigate the integrity of sympathetic innervation in the hypomelanotic macules of tuberous sclerosis complex, we studied sudomotor function in nine patients with tuberous sclerosis complex. Postganglionic sudomotor function was assessed using the Silastic imprint test in nine patients with tuberous sclerosis complex who have at least one hypomelanotic macule greater than 2 cm in diameter. Sweating was induced by iontophoresis with 0.5% pilocarpine nitrate and sweat droplets were counted under a microscope using a 1 x 1 cm grid. Silastic imprint testing of an analogous skin area contralateral to the hypomelanotic macule was measured as a control. Sweat volume quantitation using sweat collectors was performed in five of the subjects. The sweat volume collected from the hypomelanotic macule was reduced compared to the control skin in four of the five subjects. Sweat droplet counts from the hypomelanotic macule were significantly reduced in only one of nine subjects. These data suggest that, although there is no difference in the number of functioning sweat glands in most hypomelanotic macules, the sweat glands produce less sweat (ie, decreased sweat volume) than in normal skin. We hypothesize that focal abnormalities of sympathetic innervation might be responsible for the hypomelanotic macules of tuberous sclerosis complex.

Sweat: a sample with limited present applications and promising future in metabolomics.

PubMed

Mena-Bravo, A; Luque de Castro, M D

2014-03-01

Sweat is a biofluid with present scant use as clinical sample. This review tries to demonstrate the advantages of sweat over other biofluids such as blood or urine for routine clinical analyses and the potential when related to metabolomics. With this aim, critical discussion of sweat samplers and equipment for analysis of target compounds in this sample is made. Well established routine analyses in sweat as is that to diagnose cystic fibrosis, and the advantages and disadvantages of sweat versus urine or blood for doping control have also been discussed. Methods for analytes such as essential metals and xenometals, ethanol and electrolytes in sweat in fact constitute target metabolomics approaches or belong to any metabolomics subdiscipline such as metallomics, ionomics or xenometabolomics. The higher development of biomarkers based on genomics or proteomics as omics older than metabolomics is discussed and also the potential role of metabolomics in systems biology taking into account its emergent implementation. Normalization of the volume of sampled sweat constitutes a present unsolved shortcoming that deserves investigation. Foreseeable trends in this area are outlined. Copyright © 2013 Elsevier B.V. All rights reserved.

Sweat as an Efficient Natural Moisturizer.

PubMed

Shiohara, Tetsuo; Sato, Yohei; Komatsu, Yurie; Ushigome, Yukiko; Mizukawa, Yoshiko

2016-01-01

Although recent research on the pathogenesis of allergic skin diseases such as atopic dermatitis has focused on defects in skin genes important for maintaining skin barrier function, the fact that excreted sweat has an overwhelmingly great capacity to increase skin surface hydration and contains moisturizing factors has long been ignored: the increase in water loss induced by these gene defects could theoretically be compensated fully by a significant increase in sweating. In this review, the dogma postulating the detrimental role of sweat in these diseases has been challenged on the basis of recent findings on the physiological functions of sweat, newly recognized sweat gland-/duct-related skin diseases, and therapeutic approaches to the management of these diseases. We are now beginning to appreciate that sweat glands/ducts are a sophisticated regulatory system. Furthermore, depending on their anatomical location and the degree of the impairment, this system might have a different function: sweating responses in sweat glands/ducts located at the folds in hairy skin such as on the trunk and extremities could function as natural regulators that maintain skin hydration under quiescent basal conditions, in addition to the better-studied thermoregulatory functions, which can be mainly mediated by those at the ridges. The normal functioning of sweat could be disturbed in various inflammatory skin diseases. Thus, we should recognize sweating disturbance as an etiologic factor in the development of these diseases. © 2016 S. Karger AG, Basel.

Sweat glucose and GLUT2 expression in atopic dermatitis: Implication for clinical manifestation and treatment

PubMed Central

Ono, Emi; Mori, Yuki; Yoshioka, Yoshichika; Nomura, Yuko; Munetsugu, Takichi; Yokozeki, Hiroo; Katayama, Ichiro

2018-01-01

Sweat includes active components and metabolites, which are needed to maintain skin homeostasis. Component changes in sweat derived from atopic dermatitis (AD) have been reported. To investigate the influence of sweat components on the pathogenesis of AD, we performed a multifaceted assessment, including nuclear magnetic resonance spectroscopy-based metabolomic analysis, and linked these features to clinical features of AD. Distinctive properties of AD sweat are the quite-variation in protein, anti-microbial peptides and glucose concentrations. pH, sodium, and other salt levels in sweat of AD were comparable to that of healthy subjects. Sweat from AD patients with acute inflammation had a more prominent increase in glucose concentration than sweat from healthy individuals or those with AD with chronic inflammation. Topical glucose application delayed recovery of transepidermal water loss in barrier-disrupted mice. Furthermore, the glucose transporter GLUT2 was highly expressed in the lumen of sweat glands from AD patients. AD patients with chronic inflammation had significantly increased GLUT2 mRNA expression and near normal sweat glucose levels. Despite the small sample size in our study, we speculate that the increased glucose levels might be affected by AD severity and phenotype. We hope that this report will bring novel insight into the impact of sweat components on the clinical manifestation of AD. PMID:29677207

The Native American Sweat Lodge as Metaphor for Group Work.

ERIC Educational Resources Information Center

Garrett, Michael Walkingstick; Osborne, W. Larry

1995-01-01

Discusses how the interrelationship and growth emphasized by the Native American sweat lodge ceremony and "the talking circle" can provide a richer understanding of group counseling. Details each ceremony and explores the implications of practices that are based on cultural traditions, arguing that such traditions can enrich the group…

Sweat chloride and immunoreactive trypsinogen in infants carrying two CFTR mutations and not affected by cystic fibrosis.

PubMed

Castellani, Carlo; Tridello, Gloria; Tamanini, Anna; Assael, Baroukh M

2017-07-01

Newborns with raised immunotrypsinogen levels who have non-pathological sweat chloride values and carry two cystic fibrosis transmembrane regulator ( CFTR ) mutations of which at least one is not acknowledged to be cystic fibrosis (CF)-causing are at risk of developing clinical manifestations consistent with CFTR-related disorders or even CF. It is not known whether newborns with similar genotypes and normal immunoreactive trypsinogen (IRT) may share the same risk. This study found that newborns with these characteristics and normal IRT have lower sweat chloride values than those with raised IRT (p=0.007). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Fungal protein MGL_1304 in sweat is an allergen for atopic dermatitis patients.

PubMed

Hiragun, Takaaki; Ishii, Kaori; Hiragun, Makiko; Suzuki, Hidenori; Kan, Takanobu; Mihara, Shoji; Yanase, Yuhki; Bartels, Joachim; Schröder, Jens-M; Hide, Michihiro

2013-09-01

Sweat is a major aggravating factor of atopic dermatitis (AD) and approximately 80% of patients with AD show type I hypersensitivity against sweat. To identify and characterize an antigen in sweat that induces histamine release from basophils of patients with AD. Basophil histamine-releasing activity in sweat was purified by a combination of chromatographies, and proteins were analyzed with mass spectrometry. Recombinant proteins of the sweat antigen were generated, and their biological characteristics were studied by immunoblots, histamine release tests, and neutralization assays. We identified a fungal protein, MGL_1304, derived from Malassezia globosa (M globosa) in the purified sweat antigen. Recombinant MGL_1304 induced histamine release from basophils of most of the patients with AD, in accordance with the semi-purified sweat antigen. Moreover, recombinant MGL_1304 abolished the binding of serum IgE of patients with AD to the semi-purified sweat antigen, or vice versa in immunoblot analysis, and attenuated the sensitization of RBL-48 mast cells expressing human FcɛRI by serum IgE. Studies of truncated mutants of MGL_1304 indicated that IgE of patients with AD recognized the conformational structure of MGL_1304 rather than short peptide sequences. Western blot analysis of the whole lysate, the culture supernatant of M globosa, and the semi-purified sweat antigen showed that MGL_1304 was produced as a minor immunological antigen of M globosa with posttranslational modification, cleaved, and secreted as a 17-kDa major histamine-releasing sweat antigen. MGL_1304 is a major allergen in human sweat and could cause type I allergy in patients with AD. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Exercise and Fluid Balance Update

ERIC Educational Resources Information Center

Schlicht, Jeff

2005-01-01

One common piece of advice that exercise professionals give their clients is to drink water before, during, and after exercise. During exercise people can lose as much as three liters of water per hour (about 100 ounces) through sweat. Dehydration alters normal sweat patterns, which can lead to an increased core body temperature. Since most of the…

Human eccrine sweat gland cells turn into melanin-uptaking keratinocytes in dermo-epidermal skin substitutes.

PubMed

Böttcher-Haberzeth, Sophie; Biedermann, Thomas; Pontiggia, Luca; Braziulis, Erik; Schiestl, Clemens; Hendriks, Bart; Eichhoff, Ossia M; Widmer, Daniel S; Meuli-Simmen, Claudia; Meuli, Martin; Reichmann, Ernst

2013-02-01

Recently, Biedermann et al. (2010) have demonstrated that human eccrine sweat gland cells can develop a multilayered epidermis. The question still remains whether these cells can fulfill exclusive and very specific functional properties of epidermal keratinocytes, such as the incorporation of melanin, a feature absent in sweat gland cells. We added human melanocytes to eccrine sweat gland cells to let them develop into an epidermal analog in vivo. The interaction between melanocytes and sweat gland-derived keratinocytes was investigated. The following results were gained: (1) macroscopically, a pigmentation of the substitutes was seen 2-3 weeks after transplantation; (2) we confirmed the development of a multilayered, stratified epidermis with melanocytes distributed evenly throughout the basal layer; (3) melanocytic dendrites projected to suprabasal layers; and (4) melanin was observed to be integrated into former eccrine sweat gland cells. These skin substitutes were similar or equal to skin substitutes cultured from human epidermal keratinocytes. The only differences observed were a delay in pigmentation and less melanin uptake. These data suggest that eccrine sweat gland cells can form a functional epidermal melanin unit, thereby providing striking evidence that they can assume one of the most characteristic keratinocyte properties.

De novo epidermal regeneration using human eccrine sweat gland cells: higher competence of secretory over absorptive cells.

PubMed

Pontiggia, Luca; Biedermann, Thomas; Böttcher-Haberzeth, Sophie; Oliveira, Carol; Braziulis, Erik; Klar, Agnieszka S; Meuli-Simmen, Claudia; Meuli, Martin; Reichmann, Ernst

2014-06-01

In our previous work, we showed that human sweat gland-derived epithelial cells represent an alternative source of keratinocytes to grow a near normal autologous epidermis. The role of subtypes of sweat gland cells in epidermal regeneration and maintenance remained unclear. In this study, we compare the regenerative potential of both secretory and absorptive sweat gland cell subpopulations. We demonstrate the superiority of secretory over absorptive cells in forming a new epidermis on two levels: first, the proliferative and colony-forming efficiencies in vitro are significantly higher for secretory cells (SCs), and second, SCs show a higher frequency of successful epidermis formation as well as an increase in the thickness of the formed epidermis in the in vitro and in vivo functional analyses using a 3D dermo-epidermal skin model. However, the ability of forming functional skin substitutes is not limited to SCs, which supports the hypothesis that multiple subtypes of sweat gland epithelial cells hold regenerative properties, while the existence and exact localization of a keratinocyte stem cell population in the human eccrine sweat gland remain elusive.

Study on moisture absorption and sweat discharge of honeycomb polyester fiber

NASA Astrophysics Data System (ADS)

Feng, Aifen; Zhang, Yongjiu

2015-07-01

The moisture absorption and liberation properties of honeycomb polyester fiber were studied in order to understand its moisture absorption and sweat discharge. Through testing moisture absorption and liberation regains of honeycomb polyester fiber and normal polyester fiber in standard atmospheric conditions, their moisture absorption and liberation curves were depicted, and the regression equations of moisture regains to time during their reaching the balance of moisture absorption and moisture liberation were obtained according to the curves. Their moisture absorption and liberation rate curves were analyzed and the regression equations of the rates to time were obtained. The results shows that the moisture regain of honeycomb polyester fiber is much bigger than the normal polyester fiber's, and the initial moisture absorption and moisture liberation rates of the former are much higher than the latter's, so that the moisture absorbance and sweat discharge of honeycomb polyester fiber are excellent.

Highly abundant defense proteins in human sweat as revealed by targeted proteomics and label-free quantification mass spectrometry.

PubMed

Csősz, É; Emri, G; Kalló, G; Tsaprailis, G; Tőzsér, J

2015-10-01

The healthy human skin with its effective antimicrobial defense system forms an efficient barrier against invading pathogens. There is evidence suggesting that the composition of this chemical barrier varies between diseases, making the easily collected sweat an ideal candidate for biomarker discoveries. Our aim was to provide information about the normal composition of the sweat, and to study the chemical barrier found at the surface of skin. Sweat samples from healthy individuals were collected during sauna bathing, and the global protein panel was analysed by label-free mass spectrometry. SRM-based targeted proteomic methods were designed and stable isotope labelled reference peptides were used for method validation. Ninety-five sweat proteins were identified, 20 of them were novel proteins. It was shown that dermcidin is the most abundant sweat protein, and along with apolipoprotein D, clusterin, prolactin-inducible protein and serum albumin, they make up 91% of secreted sweat proteins. The roles of these highly abundant proteins were reviewed; all of which have protective functions, highlighting the importance of sweat glands in composing the first line of innate immune defense system, and maintaining the epidermal barrier integrity. Our findings with regard to the proteins forming the chemical barrier of the skin as determined by label-free quantification and targeted proteomics methods are in accordance with previous studies, and can be further used as a starting point for non-invasive sweat biomarker research. © 2015 European Academy of Dermatology and Venereology.

Mycostatic effect of recombinant dermcidin against Trichophyton rubrum and reduced dermcidin expression in the sweat of tinea pedis patients.

PubMed

Arai, Satoru; Yoshino, Takashi; Fujimura, Takao; Maruyama, Sachie; Nakano, Toshiaki; Mukuno, Akira; Sato, Naoya; Katsuoka, Kensei

2015-01-01

Trichophytosis, a common dermatophytosis, affects nearly 20-25% of the world's population. However, little is known about mechanisms for preventing colonization of Trichophyton on the skin. Dermcidin, an antimicrobial peptide that provides innate immunity to the skin and is constitutively secreted even in the absence of inflammatory stimulation, was studied to elucidate its antimycotic activity against Trichophyton. Recombinant dermcidin was determined to have antimycotic activity against Trichophyton rubrum, as evaluated by colony-forming unit (CFU) assays. The killing rate of dermcidin was 40.5% and 93.4% at 50 μg/mL (the average dermcidin concentration in healthy subjects) and 270 μg/mL, respectively. An effect of dermcidin treatment was found to be a reduction of the metabolic activity of Trichophyton as determined by nicotinamide adenine dinucleotide assay. Further, dermcidin concentrations in sweat of tinea pedis patients were found to be lower than those of healthy subjects. These findings suggest a mycostatic role for dermcidin, at normal sweat concentrations. Accordingly, we suspect that dermcidin, at normal sweat concentrations, inhibits growth of Trichophyton, where Trichophyton is subsequently eliminated in conjunction with epidermis turnover. Dermcidin, therefore, appears to play a role in the skin protection mechanism that prevents colonization of tinea pedis. © 2014 Japanese Dermatological Association.

Effect of Exercise-induced Sweating on facial sebum, stratum corneum hydration, and skin surface pH in normal population.

PubMed

Wang, Siyu; Zhang, Guirong; Meng, Huimin; Li, Li

2013-02-01

Evidence demonstrated that sweat was an important factor affecting skin physiological properties. We intended to assess the effects of exercise-induced sweating on the sebum, stratum corneum (SC) hydration and skin surface pH of facial skin. 102 subjects (aged 5-60, divided into five groups) were enrolled to be measured by a combination device called 'Derma Unit SSC3' in their frontal and zygomatic regions when they were in a resting state (RS), at the beginning of sweating (BS), during excessive sweating (ES) and an hour after sweating (AS), respectively. Compared to the RS, SC hydration in both regions increased at the BS or during ES, and sebum increased at the BS but lower during ES. Compared to during ES, Sebum increased in AS but lower than RS. Compared to the RS, pH decreased in both regions at the BS in the majority of groups, and increased in frontal region during ES and in zygomatic region in the AS. There was an increase in pH in both regions during ES in the majority of groups compared to the BS, but a decrease in the AS compared to during ES. The study implies that even in summer, after we sweat excessively, lipid products should be applied locally in order to maintain stability of the barrier function of the SC. The study suggests that after a short term(1 h or less) of self adjustment, excessive sweat from moderate exercise will not impair the primary acidic surface pH of the facial skin. Exercise-induced sweating significantly affected the skin physiological properties of facial region. © 2012 John Wiley & Sons A/S.

Immunohistochemical evidence suggests intrinsic regulatory activity of human eccrine sweat glands

PubMed Central

ZANCANARO, CARLO; MERIGO, FLAVIA; CRESCIMANNO, CATERINA; ORLANDINI, SIMONETTA; OSCULATI, ANTONIO

1999-01-01

Immunohistochemistry of normal eccrine sweat glands was performed on paraffin sections of human skin. Immunoreactivity (ir) for neuron specific enolase, S100 protein (S100), regulatory peptides, nitric oxide synthase type I (NOS-I) and choline-acetyltransferase (ChAT) was found in small nerve bundles close to sweat glands. In the glands, secretory cells were labelled with anticytokeratin antibody. Using antibodies to S100, calcitonin gene-related peptide (CGRP) and substance P (SP) a specific distribution pattern was found in secretory cells. Granulated (dark) and parietal (clear) cells were immunopositive for CGRP, and S100 and SP, respectively. Immunoreactivity was diffuse in the cytoplasm for CGRP and S100, and peripheral for SP. Myoepithelial cells were not labelled. Electron microscopy revealed electron dense granules, probably containing peptide, in granulated cells. Using antibodies to NOS-I and ChAT, ir was exclusively found in myoepithelial cells. Immunoreactivity for the atrial natriuretic peptide was absent in sweat glands. These results provide evidence for the presence of both regulatory peptides involved in vasodilation and key enzymes for the synthesis of nitric oxide and acetylcholine in the secretory coil of human sweat glands. It is suggested that human sweat glands are capable of some intrinsic regulation in addition to that carried out by their nerve supply. PMID:10386780

Prevalence of hot flushes and night sweats around the world: a systematic review.

PubMed

Freeman, E W; Sherif, K

2007-06-01

Many studies have evaluated the relationships between ethnicity and culture, prevalence of menopausal symptoms, and attitudes toward them, but few have assessed menopausal symptoms across cultures world-wide. This paper aims to systematically review the prevalence of hot flushes and night sweats, two prevalent symptoms of menopause, across the menopausal stages in different cultures and considers potential explanations for differences in prevalence rates. Sixty-six papers formed the basis for this review. Studies were organized by geographic region, and results are presented for North America, Europe, East Asia, Southeast Asia, Australia, Latin America, South Asia, Middle East, and Africa. Studies were included if they provided quantitative information on the occurrence of hot flushes. This report focuses on hot flushes and night sweats, the most common menopausal symptoms reported in epidemiologic studies. Studies reviewed indicate that vasomotor symptoms are highly prevalent in most societies. The prevalence of these symptoms varies widely and may be influenced by a range of factors, including climate, diet, lifestyle, women's roles, and attitudes regarding the end of reproductive life and aging. Patterns in hot flush prevalence were apparent for menopausal stages and, to a lesser degree, for regional variation. Caregivers should recognize that variations exist and ask patients specific questions about symptoms and their impact on usual functioning.

Normal and PPP-affected palmoplantar sweat gland express neuroendocrine markers chromogranins and synaptophysin differently.

PubMed

Hagforsen, Eva; Michaëlsson, Gerd; Stridsberg, Mats

2010-11-01

Earlier findings indicate the acrosyringium as the target for the inflammation in the chronic and intensely inflammatory skin disease palmoplantar pustulosis (PPP). The sweat gland apparatus seems to be an immune-competent structure that probably contributes to the defence of the skin. Furthermore, the sweat gland and duct may be a hitherto unrecognized neuroendocrine organ because it expresses cholineacetyl-transferase and acetylcholinesterase, nicotinic receptors, beta-adrenergic and angiotensin receptors. The aim of this study was to obtain further information about neuroendocrine properties of the sweat gland apparatus by examining the expression of common neuroendocrine markers synaptophysin and chromogranins A and B in healthy palmar skin and in PPP skin. Synaptophysin and chromogranins were expressed in the sweat glands and ducts with some variation in the pattern and intensity of the expression. In PPP skin the expression differed, being higher and lower, depending on the part of the sweat duct. Chromogranins were further expressed in the epidermis, endothelium and inflammatory cells, but its intensity was weaker in epidermis than in the sweat gland apparatus. In most cases, chromogranins in epidermis in involved PPP were weakly expressed compared to healthy controls. The presence of synaptophysin and chromogranins in palmoplantar skin may have marked neuroendocrine effects, and the palmoplantar skin is likely to have important neuroimmuno-endocrine properties. Moreover, the altered chromogranin expression in PPP skin might influence both the neuroendocrine and neuroimmunologic properties of palmoplantar skin in these patients. These results indicate important neuroendocrine properties of the palmoplantar skin.

Dehydration and heat-related death: sweat lodge syndrome.

PubMed

Byard, Roger W; Riches, Karen J

2005-09-01

A 37-year-old Caucasian male died of dehydration and heat exposure following a sweat lodge ceremony in outback Australia. The case demonstrates difficulties that may arise in the determination of the cause of death at autopsy due to nonspecific pathologic findings in hyperthermic deaths. There are also a number of features that characterize this particular "sweat lodge syndrome," including prolonged exposure to elevated temperatures in a relatively uncontrolled environment, failure to ensure adequate hydration, failure to appreciate the significance of loss of consciousness, use of ineffective alternative methods of treatment, and delay in seeking appropriate medical care. Unfortunately, the adoption of rituals and practice from other cultures may not be a completely safe undertaking. Participants in this type of activity must be cognizant of the types of medical problems that may arise. Individuals with significant cardiovascular disease, those who are taking certain medications that predispose to hyperthermia, or those who have had large amounts of alcohol should not enter sweat lodges.

Vulvar apocrine adenocarcinoma: a case with nodal metastasis and intranodal mucinous differentiation.

PubMed

Alsaad, Khaled O; Obaidat, Nidal; Dube, Valerie; Chapman, William; Ghazarian, Danny

2009-01-01

Primary vulvar adenocarcinomas are rare tumors, and their histogenesis is not fully understood. They are classified into extramammary Paget's disease, sweat gland carcinomas, and "breast-like" adenocarcinomas of the vulva. The latter resemble adenocarcinomas arising in the breast morphologically and immunophenotypically. Rare cases of adenocarcinoma with apocrine features have been reported, and whether these neoplasms originate from the "native apocrine" sweat glands or from "anogenital mammary-like" glands are still debatable. The presence of normal mammary-like glands in the vicinity of the tumor, the transitional malignant morphological features from normal mammary-like glands and the tumor, the breast-like histological features of the tumor, and the expression of estrogen and progesterone receptors generally suggest an origin from anogenital mammary-like glands. Absence of these features points toward native apocrine sweat glands as the source of these neoplasms. In this report, we present a patient who was initially diagnosed with Paget's disease of the right vulva, which was treated by hemi-vulvectomy, and who later presented with primary vulvar apocrine adenocarcinoma with metastasis to the inguinal lymph nodes and intranodal mucinous/colloidal differentiation: a feature, to the best of our knowledge, not reported before. We also reviewed the histogenesis of the vulvar adenocarcinomas, with emphasis on the morphological features that separate the tumors arising from the anogenital mammary-like glands in the vulva from those arising from the native vulvar sweat glands.

Correlates of college students' physical activity: cross-cultural differences.

PubMed

Seo, Dong-Chul; Torabi, Mohammad R; Jiang, Nan; Fernandez-Rojas, Xinia; Park, Bock-Hee

2009-10-01

This study examined cross-cultural differences in personal and behavioral determinants of vigorous-intensity and moderate-intensity physical activity (PA) among college students living in distinctly different cultures, that is, the United States, Costa Rica, India, and South Korea. Participants of this study were recruited from randomly chosen public universities in the 4 countries during the 2006-2007 academic year. A total of 4685 students participated in the study (response rate 90%). Vigorous-intensity PA was measured by asking on how many of the past 7 days the participants participated in PA for at least 20 minutes that made them sweat or breathe hard. For moderate-intensity PA, participants were asked on how many of the past 7 days they participated in PA for at least 30 minutes that did not make them sweat or breathe hard. Findings indicate that whereas perceived overweight and fruit and vegetable consumption are relatively culture-free predictors of PA, gender and TV/video watching are culture-specific predictors. Binge drinking was not predictive of meeting the vigorous-intensity and moderate-intensity PA guidelines in any of the 4 countries.

Frequency of resonance of human sweat duct in different modes of operation

NASA Astrophysics Data System (ADS)

Tripathi, Saroj R.; Takahashi, Shogo; Kinumura, Kento; Kawase, Kodo

2018-02-01

Recently, some studies have demonstrated that the sweat ducts present in the skin play a significant role in terahertz (THz) wave interaction with human beings. It was reported that the sweat ducts act as a low-Q-factor helical antenna due to their helical structure, and resonate in the sub-terahertz frequency range according to their structural parameters, such as helix diameter and helix length. According to the antenna theory, a helical antenna resonates in two different modes of operation known as normal mode and axial mode and the dimension of the helix plays a key role to determine the frequency of resonance. Therefore, here we performed the optical coherence tomography (OCT) of number of human subjects on their palm and foot to investigate the density, distribution and morphological features of sweat ducts. Moreover, we calculated the dielectric properties of human skin using terahertz time domain spectroscopy. Based on the structural parameters of human sweat ducts and its THz dielectric properties of surrounding medium, we computed the frequency of resonance of sweat duct in different modes of operation and we found that these ducts resonate in subterahertz frequency region. We believe that these findings will facilitate further investigation of the THz-skin interaction and provide guidelines for safety levels with respect to human exposure to electromagnetic waves at these frequencies.

Prenatal Correction of X-Linked Hypohidrotic Ectodermal Dysplasia.

PubMed

Schneider, Holm; Faschingbauer, Florian; Schuepbach-Mallepell, Sonia; Körber, Iris; Wohlfart, Sigrun; Dick, Angela; Wahlbuhl, Mandy; Kowalczyk-Quintas, Christine; Vigolo, Michele; Kirby, Neil; Tannert, Corinna; Rompel, Oliver; Rascher, Wolfgang; Beckmann, Matthias W; Schneider, Pascal

2018-04-26

Genetic deficiency of ectodysplasin A (EDA) causes X-linked hypohidrotic ectodermal dysplasia (XLHED), in which the development of sweat glands is irreversibly impaired, an condition that can lead to life-threatening hyperthermia. We observed normal development of mouse fetuses with Eda mutations after they had been exposed in utero to a recombinant protein that includes the receptor-binding domain of EDA. We administered this protein intraamniotically to two affected human twins at gestational weeks 26 and 31 and to a single affected human fetus at gestational week 26; the infants, born in week 33 (twins) and week 39 (singleton), were able to sweat normally, and XLHED-related illness had not developed by 14 to 22 months of age. (Funded by Edimer Pharmaceuticals and others.).

The Italian pilot external quality assessment program for cystic fibrosis sweat test.

PubMed

Salvatore, Marco; Floridia, Giovanna; Amato, Annalisa; Censi, Federica; Carta, Claudio; de Stefano, Maria Chiara; Ferrari, Gianluca; Tosto, Fabrizio; Capoluongo, Ettore; Caruso, Ubaldo; Castaldo, Giuseppe; Cirilli, Natalia; Corbetta, Carlo; Padoan, Rita; Raia, Valeria; Taruscio, Domenica

2016-05-01

Sweat chloride test is the gold standard test for cystic fibrosis (CF) diagnosis. In 2014 the Istituto Superiore di Sanità established the Italian pilot external quality assessment program for CF sweat test (IEQA-ST). Ten laboratories, included among the 33 Italian CF Referral Centers, were selected and enrolled on the basis of their attitude to perform sweat test (ST) analysis by using methods recommended by the Italian Guidelines. They received three different sweat-like samples (normal, borderline and pathologic chloride concentration), with mock clinical indications, for analysis according to routine procedures. Assessment, performed by a panel of experts, covered analytical performance, interpretation and reporting of results; categories of "poor" and "satisfactory" performance were not defined. All data were managed through a web utility. The program identified important areas of interest and, in some case, of concern. It is important to underline that results are referred to a small proportion, i.e. about 30%, of Italian laboratories performing CF ST in the context of the Referral Centers. Data collected highlight the importance of participation in EQA programs as it may improve laboratory/clinical performance; our study represents a model for the setting up of a large-scale EQA scheme for ST. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Does extensive genotyping and nasal potential difference testing clarify the diagnosis of cystic fibrosis among patients with single-organ manifestations of cystic fibrosis?

PubMed

Ooi, Chee Y; Dupuis, Annie; Ellis, Lynda; Jarvi, Keith; Martin, Sheelagh; Ray, Peter N; Steele, Leslie; Kortan, Paul; Gonska, Tanja; Dorfman, Ruslan; Solomon, Melinda; Zielenski, Julian; Corey, Mary; Tullis, Elizabeth; Durie, Peter

2014-03-01

The phenotypic spectrum of cystic fibrosis (CF) has expanded to include patients affected by single-organ diseases. Extensive genotyping and nasal potential difference (NPD) testing have been proposed to assist in the diagnosis of CF when sweat testing is inconclusive. However, the diagnostic yield of extensive genotyping and NPD and the concordance between NPD and the sweat test have not been carefully evaluated. We evaluated the diagnostic outcomes of genotyping (with 122 mutations included as disease causing), sweat testing and NPD in a prospectively ascertained cohort of undiagnosed patients who presented with chronic sino-pulmonary disease (RESP), chronic/recurrent pancreatitis (PANC) or obstructive azoospermia (AZOOSP). 202 patients (68 RESP, 42 PANC and 92 AZOOSP) were evaluated; 17.3%, 22.8% and 59.9% had abnormal, borderline and normal sweat chloride results, respectively. Only 17 (8.4%) patients were diagnosable as having CF by genotyping. Compared to sweat testing, NPD identified more patients as having CF (33.2%) with fewer borderline results (18.8%). The level of agreement according to kappa statistics (and the observed percentage of agreement) between sweat chloride and NPD in RESP, PANC and AZOOSP subjects was 'moderate' (65% observed agreement), 'poor' (33% observed agreement) and 'fair' (28% observed agreement), respectively. The degree of agreement only improved marginally when subjects with borderline sweat chloride results were excluded from the analysis. The diagnosis of CF or its exclusion is not always straightforward and may remain elusive even with comprehensive evaluation, particularly among individuals who present at an older age with single-organ manifestations suggestive of CF.

Absence of arterial baroreflex modulation of skin sympathetic activity and sweat rate during whole-body heating in humans

NASA Technical Reports Server (NTRS)

Wilson, T. E.; Cui, J.; Crandall, C. G.

2001-01-01

1. Prior findings suggest that baroreflexes are capable of modulating skin blood flow, but the effects of baroreceptor loading/unloading on sweating are less clear. Therefore, this project tested the hypothesis that pharmacologically induced alterations in arterial blood pressure in heated humans would lead to baroreflex-mediated changes in both skin sympathetic nerve activity (SSNA) and sweat rate. 2. In seven subjects mean arterial blood pressure was lowered (approximately 8 mmHg) and then raised (approximately 13 mmHg) by bolus injections of sodium nitroprusside and phenylephrine, respectively. Moreover, in a separate protocol, arterial blood pressure was reduced via steady-state administration of sodium nitroprusside. In both normothermia and heat-stress conditions the following responses were monitored: sublingual and mean skin temperatures, heart rate, beat-by-beat blood pressure, skin blood flow (laser-Doppler flowmetry), local sweat rate and SSNA (microneurography from peroneal nerve). 3. Whole-body heating increased skin and sublingual temperatures, heart rate, cutaneous blood flow, sweat rate and SSNA, but did not change arterial blood pressure. Heart rate was significantly elevated (from 74 +/- 3 to 92 +/- 4 beats x min(-1); P < 0.001) during bolus sodium nitroprusside-induced reductions in blood pressure, and significantly reduced (from 92 +/- 4 to 68 +/- 4 beats x min(-1); P < 0.001) during bolus phenylephrine-induced elevations in blood pressure, thereby demonstrating normal baroreflex function in these subjects. 4. Neither SSNA nor sweat rate was altered by rapid (bolus infusion) or sustained (steady-state infusion) changes in blood pressure regardless of the thermal condition. 5. These data suggest that SSNA and sweat rate are not modulated by arterial baroreflexes in normothermic or moderately heated individuals.

Ectodermal dysplasia

MedlinePlus

... fever, because the skin cannot sweat and control temperature properly. Affected adults are unable to tolerate a ... need special measures to keep a normal body temperature. Depending on which genes are affected, other symptoms ...

Deficient Vasoactive Intestinal Peptide Innervation in the Sweat Glands of Cystic Fibrosis Patients

NASA Astrophysics Data System (ADS)

Heinz-Erian, Peter; Dey, Richard D.; Flux, Marinus; Said, Sami I.

1985-09-01

The innervation of acini and ducts of eccrine sweat glands by immunoreactive, vasoactive intestinal peptide--containing nerve fibers was sharply reduced in seven patients with cystic fibrosis compared to eight normal subjects. The decrease in innervation by this neuropeptide, which has been shown to promote blood flow and the movement of water and chloride across epithelial surfaces in other systems, may be a basic mechanism for the decreased water content and relative impermeability of the epithelium to chloride and other ions that characterize cystic fibrosis.

Diagnosis of cystic fibrosis in the kindred of an infant with CFTR-related metabolic syndrome: importance of follow-up that includes monitoring sweat chloride concentrations over time.

PubMed

Williams, Sophia N; Nussbaum, Eliezer; Chin, Terry W; Do, Paul C M; Singh, Kathryn E; Randhawa, Inderpal

2014-03-01

Newly implemented newborn screening (NBS) programs in California have resulted in a large subset of patients in whom at least two cystic fibrosis transmembrane conductance regulator (CFTR) mutations are identified, but subsequent sweat chloride analysis reveals normal or indeterminate values. These patients are diagnosed with CFTR-Related Metabolic Syndrome (CRMS). However, the natural progression and management of these patients are not clearly understood and frequently after the age of 1-year these patients are lost to follow-up with Cystic Fibrosis (CF) Centers. We present the first case of an infant who was referred to Miller Children's Hospital for a NBS positive for CF and subsequent discovery of identical mutations in six of his seven older brothers. Several siblings had positive sweat chloride results on repeat testing after the age of 3 years. We suggest the need for continued follow-up of CRMS in a CF center with diagnostic evaluation including repeat sweat chloride testing, beyond the currently recommended period. © 2013 Wiley Periodicals, Inc.

Quantitation of normal CFTR mRNA in CF patients with splice-site mutations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Z.; Olsen, J.C.; Silverman, L.M.

Previously we identified two mutations in introns of the CFTR gene associated with partially active splice sites and unusual clinical phenotypes. One mutation in intron 19 (3849+10 kb C to T) is common in CF patients with normal sweat chloride values; an 84 bp sequence from intron 19, which contains a stop codon, is inserted between exon 19 and exon 20 in most nasal CFTR transcripts. The other mutation in intron 14B (2789+5 G to A) is associated with elevated sweat chloride levels, but mild pulmonary disease; exon 14B (38 bp) is spliced out of most nasal CFTR transcipts. Themore » remaining CFTR cDNA sequences, other than the 84 bp insertion of exon 14B deletion, are identical to the published sequence. To correlate genotype and phenotype, we used quantitative RT-PCR to determine the levels of normally-spliced CFTR mRNA in nasal epithelia from these patients. CFTR cDNA was amplified (25 cycles) by using primers specific for normally-spliced species, {gamma}-actin cDNA was amplified as a standard.« less

Loss of carbonic anhydrase XII function in individuals with elevated sweat chloride concentration and pulmonary airway disease.

PubMed

Lee, Melissa; Vecchio-Pagán, Briana; Sharma, Neeraj; Waheed, Abdul; Li, Xiaopeng; Raraigh, Karen S; Robbins, Sarah; Han, Sangwoo T; Franca, Arianna L; Pellicore, Matthew J; Evans, Taylor A; Arcara, Kristin M; Nguyen, Hien; Luan, Shan; Belchis, Deborah; Hertecant, Jozef; Zabner, Joseph; Sly, William S; Cutting, Garry R

2016-05-15

Elevated sweat chloride levels, failure to thrive (FTT), and lung disease are characteristic features of cystic fibrosis (CF, OMIM #219700). Here we describe variants in CA12 encoding carbonic anhydrase XII in two pedigrees exhibiting CF-like phenotypes. Exome sequencing of a white American adult diagnosed with CF due to elevated sweat chloride, recurrent hyponatremia, infantile FTT and lung disease identified deleterious variants in each CA12 gene: c.908-1 G>A in a splice acceptor and a novel frameshift insertion c.859_860insACCT. In an unrelated consanguineous Omani family, two children with elevated sweat chloride, infantile FTT, and recurrent hyponatremia were homozygous for a novel missense variant (p.His121Gln). Deleterious CFTR variants were absent in both pedigrees. CA XII protein was localized apically in human bronchiolar epithelia and basolaterally in the reabsorptive duct of human sweat glands. Respiratory epithelial cell RNA from the adult proband revealed only aberrant CA12 transcripts and in vitro analysis showed greatly reduced CA XII protein. Studies of ion transport across respiratory epithelial cells in vivo and in culture revealed intact CFTR-mediated chloride transport in the adult proband. CA XII protein bearing either p.His121Gln or a previously identified p.Glu143Lys missense variant localized to the basolateral membranes of polarized Madin-Darby canine kidney (MDCK) cells, but enzyme activity was severely diminished when assayed at physiologic concentrations of extracellular chloride. Our findings indicate that loss of CA XII function should be considered in individuals without CFTR mutations who exhibit CF-like features in the sweat gland and lung. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Skin grafting impairs postsynaptic cutaneous vasodilator and sweating responses.

PubMed

Davis, Scott L; Shibasaki, Manabu; Low, David A; Cui, Jian; Keller, David M; Purdue, Gary F; Hunt, John L; Arnoldo, Brett D; Kowalske, Karen J; Crandall, Craig G

2007-01-01

This study tested the hypothesis that postsynaptic cutaneous vascular responses to endothelial-dependent and -independent vasodilators, as well as sweat gland function, are impaired in split-thickness grafted skin 5 to 9 months after surgery. Intradermal microdialysis membranes were placed in grafted and adjacent control skin, thereby allowing local delivery of the endothelial-dependent vasodilator, acetylcholine (ACh; 1 x 10(-7) to 1 x 10(-1) M at 10-fold increments) and the endothelial-independent nitric oxide donor, sodium nitroprusside (SNP; 5 x 10(-8) to 5 x 10(-2) M at 10-fold increments). Skin blood flow and sweat rate were simultaneously assessed over the semipermeable portion of the membrane. Cutaneous vascular conductance (CVC) was calculated from the ratio of laser Doppler-derived skin blood flow to mean arterial blood pressure. deltaCVC responses from baseline to these drugs were modeled via nonlinear regression curve fitting to identify the dose of ACh and SNP causing 50% of the maximal vasodilator response (EC50). A rightward shift in the CVC dose response curve for ACh was observed in grafted (EC50 = -2.61 +/- 0.44 log M) compared to adjacent control skin (EC50 = -3.34 +/- 0.46 log M; P = .003), whereas the mean EC50 for SNP was similar between grafted (EC50 = -4.21 +/- 0.94 log M) and adjacent control skin (EC50 = -3.87 +/- 0.65 log M; P = 0.332). Only minimal sweating to exogenous ACh was observed in grafted skin whereas normal sweating was observed in control skin. Increased EC50 and decreased maximal CVC responses to the exogenous administration of ACh suggest impairment of endothelial-dependent cutaneous vasodilator responses in grafted skin 5 to 9 months after surgery. Greatly attenuated sweating responses to ACh suggests either abnormal or an absence of functional sweat glands in the grafted skin.

Measurement of nasal potential difference in young children with an equivocal sweat test following newborn screening for cystic fibrosis.

PubMed

Sermet-Gaudelus, Isabelle; Girodon, Emmanuelle; Roussel, Delphine; Deneuville, Eric; Bui, Stéphanie; Huet, Frédéric; Guillot, Marcel; Aboutaam, Rola; Renouil, Michel; Munck, Anne; des Georges, Marie; Iron, Albert; Thauvin-Robinet, Christel; Fajac, Isabelle; Lenoir, Gerard; Roussey, Michel; Edelman, Aleksander

2010-06-01

A challenging problem arising from cystic fibrosis (CF) newborn screening is the significant number of infants with hypertrypsinaemia (HIRT) with sweat chloride levels in the intermediate range and only one or no identified CF-causing mutations. To investigate the diagnostic value for CF of assessing CF transmembrane conductance regulator (CFTR) protein function by measuring nasal potential difference in children with HIRT. A specially designed protocol was used to assess nasal potential difference (NPD) in 23 young children with HIRT (3 months-4 years) with inconclusive neonatal screening. Results were analysed with a composite score including CFTR-dependent sodium and chloride secretion. Results were correlated with genotype after extensive genetic screening and with clinical phenotype at follow-up 3 years later. NPD was interpretable for 21 children with HIRT: 13 had NPD composite scores in the CF range. All 13 were finally found to carry two CFTR mutations. At follow-up, nine had developed a chronic pulmonary disease consistent with a CF diagnosis. The sweat test could be repeated in nine children, and six had sweat chloride values >or=60 mmol/l. Of the eight children with normal NPD scores, only two had two CFTR mutations, both wide-spectrum mutations. None had developed a CF-like lung disease at follow-up. The sweat test could be reassessed in five of these eight children and all had sweat chloride values <60 mmol/l. CF diagnosis was ruled out in six of these eight children. Evaluation of CFTR function in the nasal epithelium of young children with inconclusive results at CF newborn screening is a useful diagnostic tool for CF.

Peritoneal tuberculosis with elevated serum Ca-125 level mimicking advanced stage ovarian cancer: a case report.

PubMed

Tan, Orkun; Luchansky, Edward; Rosenman, Stephen; Pua, Tarah; Azodi, Masoud

2009-08-01

Tuberculosis is still a common problem in immigrant population with peritoneal tuberculosis as the most common presentation of extrapulmonary disease. A 36-year-old woman presented with abdominal distention, night sweats and weight loss. Physical examination and radiologic studies revealed ascites, omental caking and bilateral enlarged ovaries with an elevated serum Ca-125 of 353 U/mL. Acid-fast stain and culture were negative for Mycobacterium tuberculosis. Diagnostic laparoscopy and biopsy revealed multiple granulomas with epithelioid cells and caseification necrosis confirming tuberculosis. Treatment with anti-tuberculin drugs resulted in resolution of symptoms with a reduction in Ca-125 to normal. Laparoscopic biopsy with frozen section evaluation would spare patients with peritoneal tuberculosis from unnecessary extensive surgery. Serum Ca-125 level may be useful in monitoring treatment response.

Variability of hair coat and skin traits as related to adaptation in Criollo Limonero cattle.

PubMed

Landaeta-Hernández, Antonio; Zambrano-Nava, Sunny; Hernández-Fonseca, Juan P; Godoy, Rosario; Calles, Marcos; Iragorri, José L; Añez, Lauderys; Polanco, Miguel; Montero-Urdaneta, Merilio; Olson, Tim

2011-03-01

The variation in hair coat and skin histology traits of Criollo Limonero cattle was analyzed using 213 Criollo Limonero females. Skin biopsies were obtained from slick-haired (N=16) and normal-haired (N=14) animals. Measured traits included hair length (HL), color coat (CC), number of hair follicles per square centimeter (NHF), sweat glands per square centimeter (NSG), sweat glands size (SGS), sebaceous glands per square centimeter (NSBG), blood vessels per square centimeter (NBV), and thickness of epidermis (TE). Hair length differed (P<0.001) between slick- and normal-haired animals (4.9 ± 0.12 vs 10.9 ± 0.20, respectively). Differences (P<0.01) in CC (Bayo = 144/67.6% vs Red = 69/32.4%) and HL (slick-haired = 199/93.4% vs normal-haired = 14/6.5%) were found. Distribution of slick- and normal-haired animals differed (P<0.01) between bayo-coated and red-coated (139/62.2% vs 9/4.2%; respectively). Most (P<0.05) red-coated animals belonged to a single family. No differences (P>0.05) were found between slick-haired and normal-haired animals in NHF (637 ± 164 vs 587 ± 144, respectively), NSG (556 ± 134 vs 481 ± 118, respectively), NSBG (408 ± 87 vs 366 ± 77, respectively), NBV (1628 ± 393 vs 1541 ± 346, respectively), and TE (1.24 ± 0.14 vs 1.32 ± 0.12, respectively). However, SGS was greater (P<0.01) in slick-haired than normal-haired animals. In conclusion, Criollo Limonero cattle are predominantly bayo-coated, slick-haired, with a reduced number of hair follicles relative to Zebu cattle, sweat and sebaceous glands in proportion to hair follicle numbers, and with a high blood flow irrigating the skin. There is a sub-group of red-coated animals with yellow or cream skin, thicker epidermis, and with a higher frequency of normal-haired animals. It appears that the slick hair gene has been favored by natural selection in this breed.

Sweating and Body Odor

MedlinePlus

... This fluid is composed mainly of water and salt. Apocrine glands produce a milky fluid that most commonly is secreted when you're under emotional stress. This fluid is odorless until it combines with bacteria found normally on your skin. By Mayo Clinic ...

Dehydration-induced drinking in humans

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.

1982-01-01

The human tendency to experience a delay in rehydration (involuntary dehydration) after fluid loss is considered. The two primary factors contributing to involuntary dehydration are probably upright posture, and extracellular fluid and electrolyte loss by sweating from exercise and heat exposure. First, as the plasma sodium and osmotic concentrations remain virtually unchanged for supine to upright postural changes, the major stimuli for drinking appear to be associated with the hypovolemia and increase in the renin-angiotension system. Second, voluntary drinking during the heat experiments was 146% greater than in cool experiments; drinking increased by 109% with prior dehydration as opposed to normal hydration conditions; and drinking was increased by 41% after exercise as compared with the resting condition. Finally, it is concluded that the rate of sweating and the rate of voluntary fluid intake are highly correlated, and that the dispogenic factors of plasma volume, osmolality, and plasma renin activity are unrelated to sweat rate, but are likely to induce drinking in humans.

A modified ion-selective electrode method for measurement of chloride in sweat.

PubMed

Finley, P R; Dye, J A; Lichti, D A; Byers, J M; Williams, R J

1978-06-01

A modified method of analysis of sweat chloride concentration with an ion-selective electrode is presented. The original method of sweat chloride analysis proposed by the Orion Research Corporation (Cambridge, Massachusetts 02139) is inadequate because it produces erratic and misleading results. The modified method was compared with the reference quantitative method of Gibson and Cooke. In the modified method, individual electrode pads are cut and placed in the electrodes rather than using the pads supplied by the company; pilocarpine nitrate (2,000 mg/l) is used in place of pilocarpine HCl (640 mg/l); sodium bicarbonate as the weak electrolyte is used instead of K2SO4. A 10-minute period for sweat accumulation is employed rather than a zero-time collection as in the original Orion method. The modification has been studied for reproducibility in individuals, reproducibility between right and left arm in individuals; it has been compared extensively with the quantitative method of Gibson and Cooke, both in normal individuals and in patients with cystic fibrosis. There is excellent agreement between the modified method and the quantitative reference method. There appears to be a slight bias toward higher concentrations of chloride from the right arm compared with the left arm, but this difference is not medically significant.

A Wearable Microfluidic Sensing Patch for Dynamic Sweat Secretion Analysis.

PubMed

Nyein, Hnin Yin Yin; Tai, Li-Chia; Ngo, Quynh Phuong; Chao, Minghan; Zhang, George B; Gao, Wei; Bariya, Mallika; Bullock, James; Kim, Hyungjin; Fahad, Hossain M; Javey, Ali

2018-05-25

Wearable sweat sensing is a rapidly rising research area driven by its promising potential in health, fitness, and diagnostic applications. Despite the growth in the field, major challenges in relation to sweat metrics remain to be addressed. These challenges include sweat rate monitoring for its complex relation with sweat compositions and sweat sampling for sweat dynamics studies. In this work, we present a flexible microfluidic sweat sensing patch that enhances real-time electrochemical sensing and sweat rate analysis via sweat sampling. The device contains a spiral-patterned microfluidic component that is embedded with ion-selective sensors and an electrical impedance-based sweat rate sensor on a flexible plastic substrate. The patch is enabled to autonomously perform sweat analysis by interfacing the sensing component with a printed circuit board that is capable of on-site signal conditioning, analysis, and transmission. Progressive sweat flow in the microfluidic device, governed by the pressure induced by the secreted sweat, enhances sweat sampling and electrochemical detection via a defined sweat collection chamber and a directed sweat route. The characteristic of the sweat rate sensor is validated through a theoretical simulation, and the precision and accuracy of the flow rate is verified with a commercial syringe pump and a Macroduct sweat collector. On-body simultaneous monitoring of ion (H + , Na + , K + , Cl - ) concentration and sweat rate is also demonstrated for sensor functionality. This sweat sensing patch provides an integrated platform for a comprehensive sweat secretion analysis and facilitates physiological and clinical investigations by closely monitoring interrelated sweat parameters.

Natural history and clinical manifestations of hyponatremia and hyperchlorhidrosis due to carbonic anhydrase XII deficiency.

PubMed

Feinstein, Yael; Yerushalmi, Baruch; Loewenthal, Neta; Alkrinawi, Soliman; Birk, Ohad S; Parvari, Ruti; Hershkovitz, Eli

2014-01-01

We identified patients of Bedouin origin with a mutation in carbonic anhydrase XII (CA XII) leading to hyponatremia due to excessive salt loss via sweat. The medical records of patients were reviewed for clinical and laboratory data. A total of 11 subjects were identified; 7 symptomatic patients presented with hyponatremic dehydration in infancy. Screening of the entire kindred identified 4 asymptomatic individuals with elevated sweat chloride. All symptomatic patients had failure to thrive and moderate-severe hyponatremia (106-124 mmol·l(-1)); 6 had hypochloremia (79-94 mmol·l(-1)). All asymptomatic subjects had normal or near-normal serum sodium and chloride concentrations. Both symptomatic and asymptomatic subjects had normal renal functions and normal cortisol response on low-dose ACTH test. All symptomatic patients were treated by dietary salt, which prevents episodes of hyponatremic dehydration and promotes growth. At follow-up, the chief complaints remained heat intolerance, accumulation of salt precipitates on the face and hyperhidrosis. No evidence for chronic renal, respiratory, gastrointestinal or fertility abnormalities was found. Recognizing this newly described entity and differentiating it from cystic fibrosis and pseudohypoaldosteronism are important. Patients with CA XII mutations should be followed even after early childhood, especially in hot temperatures and intense physical activity. © 2014 S. Karger AG, Basel.

Usefulness of Sweat Management for Patients with Adult Atopic Dermatitis, regardless of Sweat Allergy: A Pilot Study.

PubMed

Kaneko, Sakae; Murota, Hiroyuki; Murata, Susumu; Katayama, Ichiro; Morita, Eishin

2017-01-01

Background . Sweat is an aggravating factor in atopic dermatitis (AD), regardless of age. Sweat allergy may be involved in AD aggravated by sweating. Objective. We investigated whether sweat exacerbates adult AD symptoms and examined the extent of sweat allergy's involvement. Method. We asked 34 AD patients (17 men, 17 women; mean age: 27.8 years) to record the extent to which sweat aggravated their symptoms on a 10-point numerical scale. Participant responses were compared with histamine release tests (HRT). Furthermore, 24 of the patients received instructions on methods of sweat management, and their outcomes were evaluated on a 10-point scale. Results. Sweat HRT results were class ≥ 2 in 13 patients, but HRT results were not correlated with the patients' self-assessments of symptom aggravation by sweat. One month after receiving sweat management instructions, a low mean score of 4.6 was obtained regarding whether active sweating was good, but a high mean score of 7.0 was obtained in response to whether the sweat management instructions had been helpful. Conclusion . Our investigation showed that patients' negative impressions of sweat might derive from crude personal experiences that are typically linked to sweating. Sweat management for patients with adult atopic dermatitis was extremely useful regardless of sweat allergy.

Dynamic analysis for mental sweating of a group of eccrin sweat glands on a human fingertip by optical coherence tomography

NASA Astrophysics Data System (ADS)

Ohmi, Masato; Tanigawa, Motomu; Wada, Yuki; Haruna, Masamitsu

2011-05-01

OCT is highly potential for in vivo observation of human sweating dynamics which affects activity of the sympathetic nerve. In this paper, we demonstrate dynamic OCT analysis of mental sweating of a group of eccrin sweat glands. The sweating dynamics is tracked simultaneously for nineteen sweat glands by time-sequential piled-up en-face OCT images with the frame spacing of 3.3 sec. Strong non-uniformity is observed in mental sweating where the amount of excess sweat is different for each sweat gland although the sweat glands are adjacent to each other. The non-uniformity should be necessary to adjust as precisely the total amount of excess sweat as possible through the sympathetic nerve in response to strength of the stress.

Medical Problems of Wearing a Coalminer's Safety Helmet

PubMed Central

Fernandez, R. H. P.

1964-01-01

A survey of 324 men, who voluntarily reported an injury to that part of the head normally covered by a miner's safety helmet, took place at 18 collieries (16,732 men) during the period March 31 to September 30, 1962. The most prevalent site for injury was the top of the head in surface workers, and the forehead in underground workers. Normally surface workers do not wear a helmet. Underground workers expose their forehead when they wear their safety helmets in an upwards-tilted position. One reason for this practice is that the helmet has become too small due to shrinkage of the sweat-dampened leather headband which occurs after the helmet has been left for some time in the hot pit-head bath lockers. A helmet which had a wide, unshrinkable, easily adjustable headband made of smooth material was worn by 31 men who had dermatitis or soreness of that part of the skin normally covered by a safety helmet. After six months 26 of these men had no signs or symptoms, confirming that the main cause of helmet dermatitis is friction. A direct relationship between skin rash and sweating was observed in only four of these men. Images PMID:14142522

Measurement of sodium concentration in sweat samples: comparison of 5 analytical techniques.

PubMed

Goulet, Eric D B; Asselin, Audrey; Gosselin, Jonathan; Baker, Lindsay B

2017-08-01

Sweat sodium concentration (SSC) can be determined using different analytical techniques (ATs), which may have implications for athletes and scientists. This study compared the SSC measured with 5 ATs: ion chromatography (IChr), flame photometry (FP), direct (DISE) and indirect (IISE) ion-selective electrode, and ion conductivity (IC). Seventy sweat samples collected from 14 athletes were analyzed with 5 instruments: the 883 Basic IC Plus (IChr, reference instrument), AAnalyst 200 (FP), Cobas 6000 (IISE), Sweat-Chek (IC), and B-722 Laqua Twin (DISE). Instruments showed excellent relative (intraclass correlation coefficient (ICC) ≥ 0.999) and absolute (coefficient of variation (CV) ≤ 2.6%) reliability. Relative validity was also excellent between ATs (ICC ≥ 0.961). In regards to the inter-AT absolute validity, compared with IChr, standard error of the estimates were similar among ATs (2.8-3.8 mmol/L), but CV was lowest with DISE (3.9%), intermediate with IISE (7.6%), and FP (6.9%) and highest with IC (12.3%). In conclusion, SSC varies depending on the AT used to analyze samples. Therefore, results obtained from different ATs are scarcely comparable and should not be used interchangeably. Nevertheless, taking into account the normal variability in SSC (∼±12%), the imprecision of the recommendations deriving from FP, IISE, IC, and DISE should have trivial health and physiological consequences under most exercise circumstances.

Sweating

MedlinePlus

... Home Body Looking and feeling your best Sweating Sweating You might think that you are only supposed to sweat when you are hot, but once you hit puberty, you will also sweat when you are nervous. Your sweat glands, which ...

Chloride and potassium channels in cystic fibrosis airway epithelia

NASA Astrophysics Data System (ADS)

Welsh, Michael J.; Liedtke, Carole M.

1986-07-01

Cystic fibrosis, the most common lethal genetic disease in Caucasians, is characterized by a decreased permeability in sweat gland duct and airway epithelia. In sweat duct epithelium, a decreased Cl- permeability accounts for the abnormally increased salt content of sweat1. In airway epithelia a decreased Cl- permeability, and possibly increased sodium absorption, may account for the abnormal respiratory tract fluid2,3. The Cl- impermeability has been localized to the apical membrane of cystic fibrosis airway epithelial cells4. The finding that hormonally regulated Cl- channels make the apical membrane Cl- permeable in normal airway epithelial cells5 suggested abnormal Cl- channel function in cystic fibrosis. Here we report that excised, cell-free patches of membrane from cystic fibrosis epithelial cells contain Cl- channels that have the same conductive properties as Cl- channels from normal cells. However, Cl- channels from cystic fibrosis cells did not open when they were attached to the cell. These findings suggest defective regulation of Cl- channels in cystic fibrosis epithelia; to begin to address this issue, we performed two studies. First, we found that isoprenaline, which stimulates Cl- secretion, increases cellular levels of cyclic AMP in a similar manner in cystic fibrosis and non-cystic fibrosis epithelial cells. Second, we show that adrenergic agonists open calcium-activated potassium channels, indirectly suggesting that calcium-dependent stimulus-response coupling is intact in cystic fibrosis. These data suggest defective regulation of Cl- channels at a site distal to cAMP accumulation.

Working Up a Good Sweat – The Challenges of Standardising Sweat Collection for Metabolomics Analysis

PubMed Central

Hussain, Joy N; Mantri, Nitin; Cohen, Marc M

2017-01-01

Introduction Human sweat is a complex biofluid of interest to diverse scientific fields. Metabolomics analysis of sweat promises to improve screening, diagnosis and self-monitoring of numerous conditions through new applications and greater personalisation of medical interventions. Before these applications can be fully developed, existing methods for the collection, handling, processing and storage of human sweat need to be revised. This review presents a cross-disciplinary overview of the origins, composition, physical characteristics and functional roles of human sweat, and explores the factors involved in standardising sweat collection for metabolomics analysis. Methods A literature review of human sweat analysis over the past 10 years (2006–2016) was performed to identify studies with metabolomics or similarly applicable ‘omics’ analysis. These studies were reviewed with attention to sweat induction and sampling techniques, timing of sweat collection, sweat storage conditions, laboratory derivation, processing and analytical platforms. Results Comparative analysis of 20 studies revealed numerous factors that can significantly impact the validity, reliability and reproducibility of sweat analysis including: anatomical site of sweat sampling, skin integrity and preparation; temperature and humidity at the sweat collection sites; timing and nature of sweat collection; metabolic quenching; transport and storage; qualitative and quantitative measurements of the skin microbiota at sweat collection sites; and individual variables such as diet, emotional state, metabolic conditions, pharmaceutical, recreational drug and supplement use. Conclusion Further development of standard operating protocols for human sweat collection can open the way for sweat metabolomics to significantly add to our understanding of human physiology in health and disease. PMID:28798503

Sweating the small stuff: adequacy and accuracy in sweat chloride determination.

PubMed

DeMarco, Mari L; Dietzen, Dennis J; Brown, Sarah M

2015-04-01

Sweat chloride testing is the gold standard for diagnosis of cystic fibrosis (CF). Our objectives were to: 1) describe variables that determine sweat rate; 2) determine the analytic and diagnostic capacity of sweat chloride analysis across the range of observed sweat rates; and 3) determine the biologic variability of sweat chloride concentration. A retrospective analysis was performed using data from all sweat chloride tests performed at St. Louis Children's Hospital over a 21-month period. A total of 1397 sweat chloride tests (1155 sufficient [≥75 mg], 242 insufficient [<75 mg]), were performed on 904 individuals. The sweat weight collected from forearms was statistically greater than that collected from legs. There was a negligible correlation between sweat weight and chloride concentration (r=-0.06). The mean individual biologic CV calculated from individuals with two or more sweat collections ≥75 mg was 13.1% (95% CI: 11.3-14.9%; range 0-88%) yielding a reference change value of 36%. Using 60 mmol/L as the diagnostic chloride cutoff, 100% of CF cases were detected whether a minimum sweat weight of 75, 40, or 20 mg was required. 1) Collection of sweat from forearms is preferable to upper legs, particularly in very young infants; 2) sweat chloride concentrations are not highly dependent upon sweat rate; 3) a change in sweat chloride concentration exceeding 36% may be considered a clinically significant response to cystic fibrosis transmembrane receptor targeted therapy, and 4) sweat collections of less than 75 mg provide clinically accurate information. Copyright © 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Dynamic analysis of mental sweating of eccrine sweat gland of human fingertip by time-sequential piled-up en face optical coherence tomography images.

PubMed

Ohmi, Masato; Wada, Yuki

2016-08-01

In this paper, we demonstrate dynamic analysis of mental sweating for sound stimulus of a few tens of eccrine sweat glands by the time-sequential piled-up en face optical coherence tomography (OCT) images with the frame spacing of 3.3 sec. In the experiment, the amount of excess sweat can be evaluated simultaneously for a few tens of sweat glands by piling up of all the en face OCT images. Non-uniformity was observed in mental sweating where the amount of sweat in response to sound stimulus is different for each sweat gland. Furthermore, the amount of sweat is significantly increased in proportion to the strength of the stimulus.

A Real-Time Wireless Sweat Rate Measurement System for Physical Activity Monitoring.

PubMed

Brueck, Andrew; Iftekhar, Tashfin; Stannard, Alicja B; Yelamarthi, Kumar; Kaya, Tolga

2018-02-10

There has been significant research on the physiology of sweat in the past decade, with one of the main interests being the development of a real-time hydration monitor that utilizes sweat. The contents of sweat have been known for decades; sweat provides significant information on the physiological condition of the human body. However, it is important to know the sweat rate as well, as sweat rate alters the concentration of the sweat constituents, and ultimately affects the accuracy of hydration detection. Towards this goal, a calorimetric based flow-rate detection system was built and tested to determine sweat rate in real time. The proposed sweat rate monitoring system has been validated through both controlled lab experiments (syringe pump) and human trials. An Internet of Things (IoT) platform was embedded, with the sensor using a Simblee board and Raspberry Pi. The overall prototype is capable of sending sweat rate information in real time to either a smartphone or directly to the cloud. Based on a proven theoretical concept, our overall system implementation features a pioneer device that can truly measure the rate of sweat in real time, which was tested and validated on human subjects. Our realization of the real-time sweat rate watch is capable of detecting sweat rates as low as 0.15 µL/min/cm², with an average error in accuracy of 18% compared to manual sweat rate readings.

Diagnosis of cystic fibrosis with chloride meter (Sherwood M926S chloride analyzer®) and sweat test analysis system (CFΔ collection system®) compared to the Gibson Cooke method.

PubMed

Emiralioğlu, Nagehan; Özçelik, Uğur; Yalçın, Ebru; Doğru, Deniz; Kiper, Nural

2016-01-01

Sweat test with Gibson Cooke (GC) method is the diagnostic gold standard for cystic fibrosis (CF). Recently, alternative methods have been introduced to simplify both the collection and analysis of sweat samples. Our aim was to compare sweat chloride values obtained by GC method with other sweat test methods in patients diagnosed with CF and whose CF diagnosis had been ruled out. We wanted to determine if the other sweat test methods could reliably identify patients with CF and differentiate them from healthy subjects. Chloride concentration was measured with GC method, chloride meter and sweat test analysis system; also conductivity was determined with sweat test analysis system. Forty eight patients with CF and 82 patients without CF underwent the sweat test, showing median sweat chloride values 98.9 mEq/L with GC method, 101 mmol/L with chloride meter, 87.8 mmol/L with sweat test analysis system. In non-CF group, median sweat chloride values were 16.8 mEq/L with GC method, 10.5 mmol/L with chloride meter, and 15.6 mmol/L with sweat test analysis system. Median conductivity value was 107.3 mmol/L in CF group and 32.1 mmol/L in non CF group. There was a strong positive correlation between GC method and the other sweat test methods with a statistical significance (r=0.85) in all subjects. Sweat chloride concentration and conductivity by other sweat test methods highly correlate with the GC method. We think that the other sweat test equipments can be used as reliably as the classic GC method to diagnose or exclude CF.

Sweating Rate and Sweat Sodium Concentration in Athletes: A Review of Methodology and Intra/Interindividual Variability.

PubMed

Baker, Lindsay B

2017-03-01

Athletes lose water and electrolytes as a consequence of thermoregulatory sweating during exercise and it is well known that the rate and composition of sweat loss can vary considerably within and among individuals. Many scientists and practitioners conduct sweat tests to determine sweat water and electrolyte losses of athletes during practice and competition. The information gleaned from sweat testing is often used to guide personalized fluid and electrolyte replacement recommendations for athletes; however, unstandardized methodological practices and challenging field conditions can produce inconsistent/inaccurate results. The primary objective of this paper is to provide a review of the literature regarding the effect of laboratory and field sweat-testing methodological variations on sweating rate (SR) and sweat composition (primarily sodium concentration [Na + ]). The simplest and most accurate method to assess whole-body SR is via changes in body mass during exercise; however, potential confounding factors to consider are non-sweat sources of mass change and trapped sweat in clothing. In addition, variability in sweat [Na + ] can result from differences in the type of collection system used (whole body or localized), the timing/duration of sweat collection, skin cleaning procedure, sample storage/handling, and analytical technique. Another aim of this paper is to briefly review factors that may impact intra/interindividual variability in SR and sweat [Na + ] during exercise, including exercise intensity, environmental conditions, heat acclimation, aerobic capacity, body size/composition, wearing of protective equipment, sex, maturation, aging, diet, and/or hydration status. In summary, sweat testing can be a useful tool to estimate athletes' SR and sweat Na + loss to help guide fluid/electrolyte replacement strategies, provided that data are collected, analyzed, and interpreted appropriately.

A Real-Time Wireless Sweat Rate Measurement System for Physical Activity Monitoring

PubMed Central

Brueck, Andrew; Iftekhar, Tashfin; Stannard, Alicja B.; Kaya, Tolga

2018-01-01

There has been significant research on the physiology of sweat in the past decade, with one of the main interests being the development of a real-time hydration monitor that utilizes sweat. The contents of sweat have been known for decades; sweat provides significant information on the physiological condition of the human body. However, it is important to know the sweat rate as well, as sweat rate alters the concentration of the sweat constituents, and ultimately affects the accuracy of hydration detection. Towards this goal, a calorimetric based flow-rate detection system was built and tested to determine sweat rate in real time. The proposed sweat rate monitoring system has been validated through both controlled lab experiments (syringe pump) and human trials. An Internet of Things (IoT) platform was embedded, with the sensor using a Simblee board and Raspberry Pi. The overall prototype is capable of sending sweat rate information in real time to either a smartphone or directly to the cloud. Based on a proven theoretical concept, our overall system implementation features a pioneer device that can truly measure the rate of sweat in real time, which was tested and validated on human subjects. Our realization of the real-time sweat rate watch is capable of detecting sweat rates as low as 0.15 µL/min/cm2, with an average error in accuracy of 18% compared to manual sweat rate readings. PMID:29439398

Quality of sweat test (ST) based on the proportion of sweat sodium (Na) and sweat chloride (Cl) as diagnostic parameter of cystic fibrosis: are we on the right way?

PubMed

Faria, Alethéa Guimarães; Marson, Fernando Augusto Lima; Gomez, Carla Cristina de Souza; Ribeiro, Maria Ângela Gonçalves de Oliveira; Morais, Lucas Brioschi; Servidoni, Maria de Fátima; Bertuzzo, Carmen Sílvia; Sakano, Eulália; Goto, Maura; Paschoal, Ilma Aparecida; Pereira, Mônica Corso; Hessel, Gabriel; Levy, Carlos Emílio; Toro, Adyléia Aparecida Dalbo Contrera; Peixoto, Andressa Oliveira; Simões, Maria Cristina Ribeiro; Lomazi, Elizete Aparecida; Nogueira, Roberto José Negrão; Ribeiro, Antônio Fernando; Ribeiro, José Dirceu

2016-10-26

To assess the quality of sweat test (ST) based on the proportion of sweat sodium and sweat chloride as diagnostic parameter of cystic fibrosis (CF). A retrospective study of 5,721 sweat samples and subsequent descriptive analysis were carried out. The test was considered "of good quality" (correct) when: (i) sweat chloride was lower than 60 mEq/L, and sweat sodium was higher than sweat chloride; (ii) sweat chloride was higher than 60 mEq/L, and sweat sodium was lower than sweat chloride. The study included 5,692/5,721 sweat samples of ST which had been requested due to clinical presentations compatible with CF and/or neonatal screenings with altered immunoreactive trypsinogen values. Considering the proportion of sweat sodium and sweat chloride as ST quality parameter, the test was performed correctly in 5,023/5,692 (88.2 %) sweat samples. The sweat chloride test results were grouped into four reference ranges for chloride (i) chloride < 30 mEq/L: 3,651/5,692 (64.1 %); (ii) chloride ≥ 30 mEq/L to < 40 mEq/L: 652/5,692 (11.5 %); (iii) ≥ 40 mEq/L to < 60 mEq/L: 673/5,692 (11.8 %); (iv) ≥ 60 mEq/L: 716/5,692 (12.6 %). In the comparative analysis, there was no association between ST quality and: (i) symptoms to indicate a ST [respiratory (p = 0.084), digestive (p = 0.753), nutritional (p = 0.824), and others (p = 0.136)], (ii) sweat weight (p = 0.416). However, there was a positive association with: (i) gender, (ii) results of ST (p < 0.001), (iii) chloride/sodium ratio (p < 0.001), (iv) subject's age at the time of ST [grouped according to category (p < 0.001) and numerical order (p < 0.001)]. For the subset of 169 patients with CF and two CFTR mutations Class I, II and/or III, in comparative analysis, there was a positive association with: (i) sweat chloride/sodium ratio (p < 0.001), (ii) sweat chloride values (p = 0.047), (iii) subject's age at the time of the ST grouped by numerical order (p = 0.001). Considering that the quality of ST can be assessed by levels of sweat sodium and sweat chloride, an increasing number of low-quality tests could be observed in our sweat samples. The quality of the test was associated with important factors, such as gender, CF diagnosis, and subjects' age.

Effect of salt supplementation on the rate of inadequate sweat collection for infants less than 3 months of age referred for the sweat test.

PubMed

Guglani, Lokesh; Abdulhamid, Ibrahim

2015-01-01

Sweat testing in young infants (≤ 3 months) with a positive newborn screen for Cystic Fibrosis (CF) can yield higher rates of inadequate sweat collection. The role of salt supplements in improving sweat collection has not been studied before. All young infants referred to our CF center for sweat testing were randomized to either receive salt supplements {1/8th teaspoon salt (750 mg)} mixed in formula feeds 1 day prior to sweat testing (study group) or no salt supplement (controls). Of the 151 young infants that underwent sweat testing over 18 months, 75 received salt supplements, while 76 did not. A total of 9 (11.8%) infants in the salt supplement group had inadequate sweat collection, as compared to 4 (5.2%) infants in the control group (p = 0.16, Fisher's Exact Test). Oral salt supplementation for young infants prior to sweat testing does not help to reduce the rates of inadequate sweat collection.

Sweat

MedlinePlus

Sweat is a clear, salty liquid produced by glands in your skin. Sweating is how your body cools itself. You sweat mainly under your arms and on your feet and palms. When sweat mixes with bacteria on your skin, it can ...

What's Sweat?

MedlinePlus

... Safe Videos for Educators Search English Español What's Sweat? KidsHealth / For Kids / What's Sweat? Print en español ¿ ... dehydrated (say: dee-HI-drayt-ed). Why Does Sweat Smell? Sweat isn't just wet — it can ...

Temperature responses of exercizing dogs to infusion of electrolytes

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Kozlowski, S.; Nazar, K.; Kaciuba-Uscilko, H.; Brzezinska, Z.

1974-01-01

The effect of infusions with solutions of various ionic and osmotic composition on exercise temperature responses was studied in dogs who do not regulate their temperature by sweating. The results suggest an association between plasma Na+ and Ca++ level within the normal physiological range and the control of body temperature during exercise.

Pituitary adenylate cyclase-activating polypeptide promotes eccrine gland sweat secretion.

PubMed

Sasaki, S; Watanabe, J; Ohtaki, H; Matsumoto, M; Murai, N; Nakamachi, T; Hannibal, J; Fahrenkrug, J; Hashimoto, H; Watanabe, H; Sueki, H; Honda, K; Miyazaki, A; Shioda, S

2017-02-01

Sweat secretion is the major function of eccrine sweat glands; when this process is disturbed (paridrosis), serious skin problems can arise. To elucidate the causes of paridrosis, an improved understanding of the regulation, mechanisms and factors underlying sweat production is required. Pituitary adenylate cyclase-activating polypeptide (PACAP) exhibits pleiotropic functions that are mediated via its receptors [PACAP-specific receptor (PAC1R), vasoactive intestinal peptide (VIP) receptor type 1 (VPAC1R) and VPAC2R]. Although some studies have suggested a role for PACAP in the skin and several exocrine glands, the effects of PACAP on the process of eccrine sweat secretion have not been examined. To investigate the effect of PACAP on eccrine sweat secretion. Reverse transcriptase-polymerase chain reaction and immunostaining were used to determine the expression and localization of PACAP and its receptors in mouse and human eccrine sweat glands. We injected PACAP subcutaneously into the footpads of mice and used the starch-iodine test to visualize sweat-secreting glands. Immunostaining showed PACAP and PAC1R expression by secretory cells from mouse and human sweat glands. PACAP immunoreactivity was also localized in nerve fibres around eccrine sweat glands. PACAP significantly promoted sweat secretion at the injection site, and this could be blocked by the PAC1R-antagonist PACAP6-38. VIP, an agonist of VPAC1R and VPAC2R, failed to induce sweat secretion. This is the first report demonstrating that PACAP may play a crucial role in sweat secretion via its action on PAC1R located in eccrine sweat glands. The mechanisms underlying the role of PACAP in sweat secretion may provide new therapeutic options to combat sweating disorders. © 2016 British Association of Dermatologists.

In vivo single human sweat gland activity monitoring using coherent anti-Stokes Raman scattering and two-photon excited autofluorescence microscopy.

PubMed

Chen, X; Gasecka, P; Formanek, F; Galey, J-B; Rigneault, H

2016-04-01

Eccrine sweat secretion is of central importance for control of body temperature. Although the incidence of sweat gland dysfunction might appear of minor importance, it can be a real concern for people with either hypohidrosis or hyperhidrosis. However, sweat gland function remains relatively poorly explored. To investigate the function of single human sweat glands. We describe a new approach for noninvasive imaging of single sweat gland activity in human palms in vivo up to a depth of 100 μm, based on nonlinear two-photon excited autofluorescence (TPEF) and coherent anti-Stokes Raman scattering (CARS). These techniques appear to be useful compared with approaches already described for imaging single sweat gland activity, as they allow better three-dimensional spatial resolution of sweat pore inner morphology and real-time monitoring of individual sweat events. By filling the sweat pore with oil and tuning the CARS contrast at 2845 cm(-1) , we imaged the ejection of sweat droplets from a single sweat gland when oil is pushed out by sweat flow. On average, sweat events lasted for about 30 s every 3 min under the conditions studied. On the other hand, about 20% of sweat glands were found inactive. TPEF and CARS were also used to study, at the single pore level, the antiperspirant action of aluminium chlorohydrate (ACH) and to reveal, for the first time in vivo, the formation of a plug at the pore entrance, in agreement with reported ACH antiperspirant mechanisms. Although data were acquired on human palms, these techniques show great promise for a better understanding of sweat secretion physiology and should be helpful to improve the efficacy of antiperspirant formulations. © 2015 British Association of Dermatologists.

Mapping axillary microbiota responsible for body odours using a culture-independent approach.

PubMed

Troccaz, Myriam; Gaïa, Nadia; Beccucci, Sabine; Schrenzel, Jacques; Cayeux, Isabelle; Starkenmann, Christian; Lazarevic, Vladimir

2015-01-01

Human axillary odour is commonly attributed to the bacterial degradation of precursors in sweat secretions. To assess the role of bacterial communities in the formation of body odours, we used a culture-independent approach to study axillary skin microbiota and correlated these data with olfactory analysis. Twenty-four Caucasian male and female volunteers and four assessors showed that the underarms of non-antiperspirant (non-AP) users have significantly higher global sweat odour intensities and harboured on average about 50 times more bacteria than those of AP users. Global sweat odour and odour descriptors sulfury-cat urine and acid-spicy generally increased from the morning to the afternoon sessions. Among non-AP users, male underarm odours were judged higher in intensity with higher fatty and acid-spicy odours and higher bacterial loads. Although the content of odour precursors in underarm secretions varied widely among individuals, males had a higher acid: sulfur precursor ratio than females did. No direct correlations were found between measured precursor concentration and sweat odours. High-throughput sequencing targeting the 16S rRNA genes of underarm bacteria collected from 11 non-AP users (six females and five males) confirmed the strong dominance of the phyla Firmicutes and Actinobacteria, with 96% of sequences assigned to the genera Staphylococcus, Corynebacterium and Propionibacterium. The proportion of several bacterial taxa showed significant variation between males and females. The genera Anaerococcus and Peptoniphilus and the operational taxonomic units (OTUs) from Staphylococcus haemolyticus and the genus Corynebacterium were more represented in males than in females. The genera Corynebacterium and Propionibacterium were correlated and anti-correlated, respectively, with body odours. Within the genus Staphylococcus, different OTUs were either positively or negatively correlated with axillary odour. The relative abundance of five OTUs (three assigned to S. hominis and one each to Corynebacterium tuberculostearicum and Anaerococcus) were positively correlated with at least one underarm olfactory descriptor. Positive and negative correlations between bacterial taxa found at the phylum, genus and OTU levels suggest the existence of mutualism and competition among skin bacteria. Such interactions, and the types and quantities of underarm bacteria, affect the formation of body odours. These findings open the possibility of developing new solutions for odour control.

Sweat Facilitated Amino Acid Losses in Male Athletes during Exercise at 32-34°C.

PubMed

Dunstan, R Hugh; Sparkes, Diane L; Dascombe, Benjamin J; Macdonald, Margaret M; Evans, Craig A; Stevens, Christopher J; Crompton, Marcus J; Gottfries, Johan; Franks, Jesse; Murphy, Grace; Wood, Ryan; Roberts, Timothy K

2016-01-01

Sweat contains amino acids and electrolytes derived from plasma and athletes can lose 1-2L of sweat per hour during exercise. Sweat may also contain contributions of amino acids as well as urea, sodium and potassium from the natural moisturizing factors (NMF) produced in the stratum corneum. In preliminary experiments, one participant was tested on three separate occasions to compare sweat composition with surface water washings from the same area of skin to assess contributions from NMF. Two participants performed a 40 minute self-paced cycle session with sweat collected from cleansed skin at regular intervals to assess the contributions to the sweat load from NMF over the period of exercise. The main study investigated sweat amino acid composition collected from nineteen male athletes following standardised endurance exercise regimes at 32-34°C and 20-30% RH. Plasma was also collected from ten of the athletes to compare sweat and plasma composition of amino acids. The amino acid profiles of the skin washings were similar to the sweat, suggesting that the NMF could contribute certain amino acids into sweat. Since the sweat collected from athletes contained some amino acid contributions from the skin, this fluid was subsequently referred to as "faux" sweat. Samples taken over 40 minutes of exercise showed that these contributions diminished over time and were minimal at 35 minutes. In the main study, the faux sweat samples collected from the athletes with minimal NMF contributions, were characterised by relatively high levels of serine, histidine, ornithine, glycine and alanine compared with the corresponding levels measured in the plasma. Aspartic acid was detected in faux sweat but not in the plasma. Glutamine and proline were lower in the faux sweat than plasma in all the athletes. Three phenotypic groups of athletes were defined based on faux sweat volumes and composition profiles of amino acids with varying relative abundances of histidine, serine, glycine and ornithine. It was concluded that for some individuals, faux sweat resulting from exercise at 32-34°C and 20-30% RH posed a potentially significant source of amino acid loss.

Sweat Facilitated Amino Acid Losses in Male Athletes during Exercise at 32-34°C

PubMed Central

Dunstan, R. Hugh; Sparkes, Diane L.; Dascombe, Benjamin J.; Macdonald, Margaret M.; Evans, Craig A.; Stevens, Christopher J.; Crompton, Marcus J.; Gottfries, Johan; Franks, Jesse; Murphy, Grace; Wood, Ryan; Roberts, Timothy K.

2016-01-01

Sweat contains amino acids and electrolytes derived from plasma and athletes can lose 1-2L of sweat per hour during exercise. Sweat may also contain contributions of amino acids as well as urea, sodium and potassium from the natural moisturizing factors (NMF) produced in the stratum corneum. In preliminary experiments, one participant was tested on three separate occasions to compare sweat composition with surface water washings from the same area of skin to assess contributions from NMF. Two participants performed a 40 minute self-paced cycle session with sweat collected from cleansed skin at regular intervals to assess the contributions to the sweat load from NMF over the period of exercise. The main study investigated sweat amino acid composition collected from nineteen male athletes following standardised endurance exercise regimes at 32–34°C and 20–30% RH. Plasma was also collected from ten of the athletes to compare sweat and plasma composition of amino acids. The amino acid profiles of the skin washings were similar to the sweat, suggesting that the NMF could contribute certain amino acids into sweat. Since the sweat collected from athletes contained some amino acid contributions from the skin, this fluid was subsequently referred to as “faux” sweat. Samples taken over 40 minutes of exercise showed that these contributions diminished over time and were minimal at 35 minutes. In the main study, the faux sweat samples collected from the athletes with minimal NMF contributions, were characterised by relatively high levels of serine, histidine, ornithine, glycine and alanine compared with the corresponding levels measured in the plasma. Aspartic acid was detected in faux sweat but not in the plasma. Glutamine and proline were lower in the faux sweat than plasma in all the athletes. Three phenotypic groups of athletes were defined based on faux sweat volumes and composition profiles of amino acids with varying relative abundances of histidine, serine, glycine and ornithine. It was concluded that for some individuals, faux sweat resulting from exercise at 32–34°C and 20–30% RH posed a potentially significant source of amino acid loss. PMID:27936120

Skin Tattoos Alter Sweat Rate and Na+ Concentration.

PubMed

Luetkemeier, Maurie Joe; Hanisko, Joseph Michael; Aho, Kyle Mathiew

2017-07-01

The popularity of tattoos has increased tremendously in the last 10 yr particularly among athletes and military personnel. The tattooing process involves permanently depositing ink under the skin at a similar depth as eccrine sweat glands (3-5 mm). The purpose of this study was to compare the sweat rate and sweat Na concentration of tattooed versus nontattooed skin. The participants were 10 healthy men (age = 21 ± 1 yr), all with a unilateral tattoo covering a circular area at least 5.2 cm. Sweat was stimulated by iontophoresis using agar gel disks impregnated with 0.5% pilocarpine nitrate. The nontattooed skin was located contralateral to the position of the tattooed skin. The disks used to collect sweat were composed of Tygon® tubing wound into a spiral so that the sweat was pulled into the tubing by capillary action. The sweat rate was determined by weighing the disk before and after sweat collection. The sweat Na concentration was determined by flame photometry. The mean sweat rate from tattooed skin was significantly less than nontattooed skin (0.18 ± 0.15 vs 0.35 ± 0.25 mg·cm·min; P = 0.001). All 10 participants generated less sweat from tattooed skin than nontattooed skin and the effect size was -0.79. The mean sweat Na concentration from tattooed skin was significantly higher than nontattooed skin (69.1 ± 28.9 vs 42.6 ± 15.2 mmol·L; P = 0.02). Nine of 10 participants had higher sweat Na concentration from tattooed skin than nontattooed skin, and the effect size was 1.01. Tattooed skin generated less sweat and a higher Na concentration than nontattooed skin when stimulated by pilocarpine iontophoresis.

Interindividual variability in sweat electrolyte concentration in marathoners.

PubMed

Lara, Beatriz; Gallo-Salazar, César; Puente, Carlos; Areces, Francisco; Salinero, Juan José; Del Coso, Juan

2016-01-01

Sodium (Na(+)) intake during exercise aims to replace the Na(+) lost by sweat to avoid electrolyte imbalances, especially in endurance disciplines. However, Na(+) needs can be very different among individuals because of the great inter-individual variability in sweat electrolyte concentration. The aim of this investigation was to determine sweat electrolyte concentration in a large group of marathoners. A total of 157 experienced runners (141 men and 16 women) completed a marathon race (24.4 ± 3.6 °C and 27.7 ± 4.8 % of humidity). During the race, sweat samples were collected by using sweat patches placed on the runners' forearms. Sweat electrolyte concentration was measured by using photoelectric flame photometry. As a group, sweat Na(+) concentration was 42.9 ± 18.7 mmol·L(-1) (minimal-maximal value = 7.0-95.5 mmol·L(-1)), sweat Cl(-) concentration was 32.2 ± 15.6 mmol·L(-1) (7.3-90.6 mmol·L(-1)) and sweat K(+) concentration was 6.0 ± 0.9 mmol·L(-1) (3.1-8.0 mmol·L(-1)). Women presented lower sweat Na(+) (33.9 ± 12.1 vs 44.0 ± 19.1 mmol·L(-1); P = 0.04) and sweat Cl(-) concentrations (22.9 ± 10.5 vs 33.2 ± 15.8 mmol·L(-1); P = 0.01) than men. A 20 % of individuals presented a sweat Na(+) concentration higher than 60 mmol·L(-1) while this threshold was not surpassed by any female marathoner. Sweat electrolyte concentration did not correlate to sweat rate, age, body characteristics, experience or training. Although there was a significant correlation between sweat Na(+) concentration and running pace (r = 0.18; P = 0.03), this association was weak to interpret that sweat Na(+) concentration increased with running pace. The inter-individual variability in sweat electrolyte concentration was not explained by any individual characteristics except for individual running pace and sex. An important portion (20 %) of marathoners might need special sodium intake recommendations due to their high sweat salt losses.

The effect of heat acclimation on sweat microminerals: Artifact of surface contamination

USDA-ARS?s Scientific Manuscript database

Heat acclimation (HA) reportedly conveys conservation in sweat micromineral concentrations when sampled from arm sweat, but time course is unknown. The observation that comprehensive cleaning of the skin surface negates sweat micromineral reductions during prolonged sweating raises the question of w...

Integrated sudomotor axon reflex sweat stimulation for continuous sweat analyte analysis with individuals at rest.

PubMed

Sonner, Zachary; Wilder, Eliza; Gaillard, Trudy; Kasting, Gerald; Heikenfeld, Jason

2017-07-25

Eccrine sweat has rapidly emerged as a non-invasive, ergonomic, and rich source of chemical analytes with numerous technological demonstrations now showing the ability for continuous electrochemical sensing. However, beyond active perspirers (athletes, workers, etc.), continuous sweat access in individuals at rest has hindered the advancement of both sweat sensing science and technology. Reported here is integration of sudomotor axon reflex sweat stimulation for continuous wearable sweat analyte analysis, including the ability for side-by-side integration of chemical stimulants & sensors without cross-contamination. This integration approach is uniquely compatible with sensors which consume the analyte (enzymatic) or sensors which equilibrate with analyte concentrations. In vivo validation is performed using iontophoretic delivery of carbachol with ion-selective and impedance sensors for sweat analysis. Carbachol has shown prolonged sweat stimulation in directly stimulated regions for five hours or longer. This work represents a significant leap forward in sweat sensing technology, and may be of broader interest to those interested in on-skin sensing integrated with drug-delivery.

SINUSITIS, BRONCHIECTASIS, AND FLATUS IN A SUMATRAN ORANGUTAN (PONGO ABELII): COULD THIS BE CYSTIC FIBROSIS?

PubMed

Stringer, Elizabeth; Cossaboon, Cindy; Han, Sushan; Taylor-Cousar, Jennifer L

2016-03-01

A 31-yr-old male Sumatran orangutan (Pongo abelii) presented with 14 yr of chronic purulent nasal drainage and cough with intermittent exacerbation of symptoms requiring systemic antibiotic treatment. He was diagnosed with a cystic fibrosis (CF)-like condition. Evaluation consisted of bronchoscopy with bronchoalveolar lavage, culture, and computed tomography scanning of the sinuses and chest. Although the presence of low fecal elastase activity increased the suspicion for a diagnosis of CF, pilocarpine iontophoresis with sweat collection and analysis ("sweat testing") was inconclusive. Medical management included twice-daily nebulization with bronchodilators and alternating month inhaled antibiotics, pancreatic enzyme replacement therapy, and simethicone as needed. Sinopulmonary and gastrointestinal symptoms improved substantially with treatment. Several years later, the animal died acutely of colonic volvulus. Necropsy and histopathology confirmed CF-like lung disease with chronic air sacculitis.

Iron losses in sweat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brune, M.; Magnusson, B.; Persson, H.

The losses of iron in whole body cell-free sweat were determined in eleven healthy men. A new experimental design was used with a very careful cleaning procedure of the skin and repeated consecutive sampling periods of sweat in a sauna. The purpose was to achieve a steady state of sweat iron losses with minimal influence from iron originating from desquamated cells and iron contaminating the skin. A steady state was reached in the third sauna period (second sweat sampling period). Iron loss was directly related to the volume of sweat lost and amounted to 22.5 micrograms iron/l sweat. The findingsmore » indicate that iron is a physiological constituent of sweat and derived not only from contamination. Present results imply that variations in the amount of sweat lost will have only a marginal effect on the variation in total body iron losses.« less

Thermogenic and psychogenic recruitment of human eccrine sweat glands: Variations between glabrous and non-glabrous skin surfaces.

PubMed

Machado-Moreira, Christiano A; Taylor, Nigel A S

2017-04-01

Human eccrine sweat-gland recruitment and secretion rates were investigated from the glabrous (volar) and non-glabrous hand surfaces during psychogenic (mental arithmetic) and thermogenic stimuli (mild hyperthermia). It was hypothesised that these treatments would activate glands from both skin surfaces, with the non-thermal stimulus increasing secretion rates primarily by recruiting more sweat glands. Ten healthy men participated in two seated, resting trials in temperate conditions (25-26°C). Trials commenced under normothermic conditions during which the first psychogenic stress was applied. That was followed by passive heating (0.5°C mean body temperature elevation) and thermal clamping, with a second cognitive challenge then applied. Sudomotor activity was evaluated from both hands, with colourimetry used to identify activated sweat glands, skin conductance to determine the onset of precursor sweating and ventilated sweat capsules to measure rates of discharged sweating. From glandular activation and sweat rate data, sweat-gland outputs were derived. These psychogenic and thermogenic stimuli activated sweat glands from both the glabrous and non-glabrous skin surfaces, with the former dominating at the glabrous skin and the latter at the non-glabrous surface. Indeed, those stimuli individually accounted for ~90% of the site-specific maximal number of activated sweat glands observed when both stimuli were simultaneously applied. During the normothermic psychological stimulation, sweating from the glabrous surface was elevated via a 185% increase in the number of activated glands within the first 60s. The hypothetical mechanism for this response may involve the serial activation of additional eccrine sweat glands during the progressive evolution of psychogenic sweating. Copyright © 2017 Elsevier Ltd. All rights reserved.

Urea transporters and sweat response to uremia.

PubMed

Keller, Raymond W; Bailey, James L; Wang, Yanhua; Klein, Janet D; Sands, Jeff M

2016-06-01

In humans, urea is excreted in sweat, largely through the eccrine sweat gland. The urea concentration in human sweat is elevated when compared to blood urea nitrogen. The sweat urea nitrogen (UN) of patients with end-stage kidney disease (ESRD) is increased when compared with healthy humans. The ability to produce sweat is maintained in the overwhelming majority of ESRD patients. A comprehensive literature review found no reports of sweat UN neither in healthy rodents nor in rodent models of chronic kidney disease (CKD). Therefore, this study measured sweat UN concentrations in healthy and uremic rats. Uninephrectomy followed by renal artery ligation was used to remove 5/6 of renal function. Rats were then fed a high-protein diet to induce uremia. Pilocarpine was used to induce sweating. Sweat droplets were collected under oil. Sweat UN was measured with a urease assay. Serum UN was measured using a fluorescent ortho-pthalaldehyde reaction. Immunohistochemistry (IHC) was accomplished with a horseradish peroxidase and diaminobenzidine technique. Sweat UN in uremic rats was elevated greater than two times compared to healthy pair-fed controls (220 ± 17 and 91 ± 15 mmol/L, respectively). Post hoc analysis showed a significant difference between male and female uremic sweat UN (279 ± 38 and 177 ± 11 mmol/L, respectively.) IHC shows, for the first time, the presence of the urea transporters UT-B and UT-A2 in both healthy and uremic rat cutaneous structures. Future studies will use this model to elucidate how rat sweat UN and other solute excretion is altered by commonly prescribed diuretics. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Testing in artificial sweat - Is less more? Comparison of metal release in two different artificial sweat solutions.

PubMed

Midander, Klara; Julander, Anneli; Kettelarij, Jolinde; Lidén, Carola

2016-11-01

Metal release from materials immersed in artificial sweat can function as a measure of potential skin exposure. Several artificial sweat models exist that, to various degree, mimic realistic conditions. Study objective was to evaluate metal release from previously examined and well characterized materials in two different artificial sweat solutions; a comprehensive sweat model intended for use within research, based on the composition of human sweat; and the artificial sweat, EN1811, intended for testing compliance with the nickel restriction in REACH. The aim was to better understand whether there are advantages using either of the sweat solutions in bio-elution testing of materials. Metal release in two different artificial sweat solutions was compared for discs of a white gold alloy and two hard metals, and a rock drilling insert of tungsten carbide at 1 h, 24 h, 1 week and 1 month. The released amount of metal was analysed by means of inductively coupled plasma mass spectrometry. Similar levels of released metals were measured from test materials in the two different artificial sweat solutions. For purposes in relation to legislations, it was concluded that a metal release test using a simple artificial sweat composition may provide results that sufficiently indicate the degree of metal release at skin contact. Copyright © 2016 Elsevier Inc. All rights reserved.

Native American-Native Siberian Cultural Exchange: Ancient Tribal Connections Come to Light in Monument Valley Study Program.

ERIC Educational Resources Information Center

Hubbard, Pat

1998-01-01

Describes the 1995-97 student exchange program between the Navajo Nation in San Juan School District, Utah, and the Khanty-Mansisk region of Siberia. Similarities were found in language, string games, folk tales, sweat lodges, clan traditions, traditional arts and crafts, and stories of ancient meetings between the two peoples and use of the…

Proteomic and peptidomic analysis of human sweat with emphasis on proteolysis.

PubMed

Yu, Yijing; Prassas, Ioannis; Muytjens, Carla M J; Diamandis, Eleftherios P

2017-02-23

Sweat is produced by eccrine and apocrine glands and represents a biological fluid with established roles in thermo-regulation and host infection defense. The composition of sweat is highly dynamic and alters significantly in various skin and other disorders. Therefore, in-depth profiling of sweat protein composition is expected to augment our understanding of the pathobiology of several skin diseases and may lead to the identification of useful sweat-based disease biomarkers. We here reported an in-depth analysis of the human sweat proteome and peptidome. Sweat was collected from healthy males and healthy females of ages 20-60years, following strenuous exercise. Two sweat pools were prepared (1 for males and 1 for females) and were subjected to sample preparation for mass spectrometric analysis. We identified a total of 861 unique proteins during our proteomic analysis and 32,818 endogenous peptides (corresponding to additional 1067 proteins) from our peptidomics workflow. As expected, the human skin was identified as the most abundant source of sweat proteins and peptides. Several skin proteases and protease inhibitors were identified in human sweat, highlighting the intense proteolytic activity of human skin. The presence of several antimicrobial peptides supports the functional roles of sweat in host defense and innate immunity. Sweat is a skin-associated biological fluid, secreted by eccrine and apocrine glands, with essential function in body thermo-regulation and host infection defense. In the present study, we performed in-depth profiling of both sweat proteome and peptidome composition. Our data provide the most in-depth characterization of the skin's catalytic network present in sweat. For the first time, we brought to light novel peptides in human sweat that potentially have antimicrobial activity, which highlight the important role of this fluid in innate immunity. All these findings allow us to have a better understanding of the complex web of proteases in skin and may act as a platform for the future discovery of novel skin biomarkers. Copyright © 2017 Elsevier B.V. All rights reserved.

Hyperhidrosis in association with efavirenz.

PubMed

Fuertes, Aurelio; Martín, Aurelio Fuertes; Cabrera, Salvador; Figueroa, Salvador Cabrera; Valverde, Maria de la Paz; Merino, María de la Paz Valverde; Domínguez-Gil, Alfonso; Hurléé, Alfonso Domínguez-Gil

2009-03-01

Hyperhidrosis may be an adverse drug event (ADE) induced by the effect on any of the components of human thermoregulation. Some of our efavirenz (EFV)-treated patients have reported excessive nocturnal sweating that resolved after dose reduction. A representative clinical case of a male patient being treated with a night-time 600-mg dose of EFV who reported severe nocturnal sweating is reported here. His EFV plasma concentrations were always above normal and he was homozygous for a deficient function-allele of CYP2D6; for this reason, his EFV dose was reduced to 400mg=d. Simultaneous with this reduction, the patient described a progressive decrease in nocturnal sweating until its complete disappearance 15-20 days after this new drug dosage. The mechanism explaining sweating could be similar to the one suggested for hyperhidrosis related to serotonin uptake inhibitors, because this hyperhidrosis is episodic, nocturnal, and dose dependent. Hyperhidrosis could correspond to a dose-dependent ADE induced by EFV, therefore, a reduction of EFV from 600 to 400mg/d seems to control it. EFV crosses the hematoencephalic barrier and reaches a mean concentration in the cerebroespinal fluid equivalent to 0.69% of the plasma concentration. The ability of EFV to accessing the central nervous system (CNS) could explain an effect on thermoregulation. Hyperhydrosis is not easily discovered through a routine anamnesis because it is not noted on the EFV package insert, so its incidence may be higher than expected. Additionally, hyperhidrosis may be an indicator of elevated EFV plasma concentrations and hence may be controlled through a reduction of dose.

Sweating - absent

MedlinePlus

... page, please enable JavaScript. An abnormal lack of sweat in response to heat may be harmful, because ... diseases or scarring of the skin that block sweat glands Trauma to sweat glands Use of certain ...

3D modeling and characterization of a calorimetric flow rate sensor for sweat rate sensing applications

NASA Astrophysics Data System (ADS)

Iftekhar, Ahmed Tashfin; Ho, Jenny Che-Ting; Mellinger, Axel; Kaya, Tolga

2017-03-01

Sweat-based physiological monitoring has been intensively explored in the last decade with the hopes of developing real-time hydration monitoring devices. Although the content of sweat (electrolytes, lactate, urea, etc.) provides significant information about the physiology, it is also very important to know the rate of sweat at the time of sweat content measurements because the sweat rate is known to alter the concentrations of sweat compounds. We developed a calorimetric based flow rate sensor using PolydimethylSiloxane that is suitable for sweat rate applications. Our simple approach on using temperature-based flow rate detection can easily be adapted to multiple sweat collection and analysis devices. Moreover, we have developed a 3D finite element analysis model of the device using COMSOL Multiphysics™ and verified the flow rate measurements. The experiment investigated flow rate values from 0.3 μl/min up to 2.1 ml/min, which covers the human sweat rate range (0.5 μl/min-10 μl/min). The 3D model simulations and analytical model calculations covered an even wider range in order to understand the main physical mechanisms of the device. With a verified 3D model, different environmental heat conditions could be further studied to shed light on the physiology of the sweat rate.

Tropical Malaysians and temperate Koreans exhibit significant differences in sweating sensitivity in response to iontophoretically administered acetylcholine

NASA Astrophysics Data System (ADS)

Lee, Jeong-Beom; Bae, Jun-Sang; Matsumoto, Takaaki; Yang, Hun-Mo; Min, Young-Ki

2009-03-01

Natives of the tropics are able to tolerate high ambient temperatures. This results from their long-term residence in hot and often humid tropical climates. This study was designed to compare the peripheral mechanisms of thermal sweating in tropical natives with that of their temperate counterparts. Fifty-five healthy male subjects including 20 native Koreans who live in the temperate Korean climate (Temperate-N) and 35 native tropical Malaysian men that have lived all of their lives in Malaysia (Tropical-N) were enrolled in this study after providing written informed consent to participate. Quantitative sudomotor axon reflex testing after iontophoresis (2 mA for 5 min) with 10% acetylcholine (ACh) was used to determine directly activated (DIR) and axon reflex-mediated (AXR) sweating during ACh iontophoresis. The sweat rate, activated sweat gland density, sweat gland output per single gland activated, and oral and skin temperature changes were measured. The sweat onset time of AXR (nicotinic-receptor-mediated) was 56 s shorter in the Temperate-N than in the Tropical-N subjects ( P < 0.0001). The nicotinic-receptor-mediated sweating activity AXR (1), and the muscarinic-receptor-mediated sweating activity DIR, in terms of sweat volume, were 103% and 59% higher in the Temperate-N compared to the Tropical-N subjects ( P < 0.0001). The Temperate-N group also had a 17.8% ( P < 0.0001) higher active sweat gland density, 35.4% higher sweat output per gland, 0.24°C higher resting oral temperature, and 0.62°C higher resting forearm skin temperature compared to the Tropical-N subjects ( P < 0.01). ACh iontophoresis did not influence oral temperature, but increased skin temperature near where the ACh was administered, in both groups. These results suggest that suppressed thermal sweating in the Tropical-N subjects was, at least in part, due to suppressed sweat gland sensitivity to ACh through both recruitment of active sweat glands and the sweat gland output per each gland. This physiological trait guarantees a more economical use of body fluids, thus ensuring more efficient protection against heat stress.

Sweat test for cystic fibrosis: Wearable sweat sensor vs. standard laboratory test.

PubMed

Choi, Dong-Hoon; Thaxton, Abigail; Jeong, In Cheol; Kim, Kain; Sosnay, Patrick R; Cutting, Garry R; Searson, Peter C

2018-03-23

Sweat chloride testing for diagnosis of cystic fibrosis (CF) involves sweat induction, collection and handling, and measurement in an analytical lab. We have developed a wearable sensor with an integrated salt bridge for real-time measurement of sweat chloride concentration. Here, in a proof-of-concept study, we compare the performance of the sensor to current clinical practice in CF patients and healthy subjects. Sweat was induced on both forearms of 10 individuals with CF and 10 healthy subjects using pilocarpine iontophoresis. A Macroduct sweat collection device was attached to one arm and sweat was collected for 30 min and then sent for laboratory analysis. A sensor was attached to the other arm and the chloride ion concentration monitored in real time for 30 min using a Bluetooth transceiver and smart phone app. Stable sweat chloride measurements were obtained within 15 min following sweat induction using the wearable sensor. We define the detection time as the time at which the standard deviation of the real-time chloride ion concentration remained below 2 mEq/L for 5 min. The sweat volume for sensor measurements at the detection time was 13.1 ± 11.4 μL (SD), in many cases lower than the minimum sweat volume of 15 μL for conventional testing. The mean difference between sweat chloride concentrations measured by the sensor and the conventional laboratory practice was 6.2 ± 9.5 mEq/L (SD), close to the arm-to-arm variation of about 3 mEq/L. The Pearson correlation coefficient between the two measurements was 0.97 highlighting the excellent agreement between the two methods. A wearable sensor can be used to make real-time measurements of sweat chloride within 15 min following sweat induction, requiring a small sweat volume, and with excellent agreement to standard methods. Copyright © 2018 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Investigating the Effects of Sweat Therapy on Group Dynamics and Affect

ERIC Educational Resources Information Center

Colmant, Stephen A.; Eason, Evan A.; Winterowd, Carrie L.; Jacobs, Sue C.; Cashel, Chris

2005-01-01

In this study, we examined the effects of sweat therapy on group dynamics and affect. Sweat therapy is the combination of intense heat exposure with psychotherapy or counseling (Colmant & Merta, 1999; 2000). Twenty-four undergraduates were separated by sex and randomly assigned to eight sessions of either a sweat or non-sweat group counseling…

Hyperhidrosis (Excessive Sweating)

MedlinePlus

... your daily routine Sweating causes emotional distress or social withdrawal You suddenly begin to sweat more than usual ... can lead to heavy sweating, as can opioid ... infections. Social and emotional effects. Having clammy or dripping hands ...

Relationship between sweat chloride, sodium, and age in clinically obtained samples.

PubMed

Traeger, Nadav; Shi, Qiuhu; Dozor, Allen J

2014-01-01

The relationship between sweat electrolytes and age is uncertain, as is the value of measuring sodium or the chloride:sodium ratio. 13,785 sweat tests performed over 23 years at one center through the Macroduct collection in clinically obtained samples were analyzed. Sweat chloride tended to decrease over the first year of life, slowly increase until the fourth decade, then either level off or slightly decrease. In children, sweat sodium overlapped between those with positive and negative sweat tests, but not in adults. If the sweat test was positive, there was a higher likelihood of having a chloride:sodium ratio >1, but most subjects with a ratio >1 did not have CF. Sweat chloride and sodium vary with age. Measurement of sweat sodium did not add discriminatory value. The proportion of subjects with a chloride:sodium ratio >1, with or without CF, varied greatly between age ranges. © 2013. Published by Elsevier B.V. on behalf of European Cystic Fibrosis Society. All rights reserved.

Night Sweats

MedlinePlus

Symptoms Night sweats By Mayo Clinic Staff Night sweats are repeated episodes of extreme perspiration that may soak your nightclothes or ... these episodes are usually not labeled as night sweats and typically aren't a sign of a ...

Genetics Home Reference: cold-induced sweating syndrome

MedlinePlus

... Health Conditions Cold-induced sweating syndrome Cold-induced sweating syndrome Printable PDF Open All Close All Enable ... view the expand/collapse boxes. Description Cold-induced sweating syndrome is characterized by problems with regulating body ...

Immediate Wheal Reactivity to Autologous Sweat in Atopic Dermatitis Is Associated with Clinical Severity, Serum Total and Specific IgE and Sweat Tryptase Activity.

PubMed

Ilves, Tiina; Virolainen, Anu; Harvima, Ilkka Tapani

2016-01-01

Sweating can worsen atopic dermatitis (AD). The purpose of this work was to study the associations between reactivity to autologous sweat and the clinical severity of AD as well as investigate the possible wheal-inducing factors of sweat. Intracutaneous skin tests with autologous sweat were performed on 50 AD patients and 24 control subjects. In skin biopsies, tryptase and PAR-2 were enzyme and immunohistochemically stained. The associations between skin test reactivity and sweat histamine concentration, tryptase or chymase activity levels, tryptase or PAR-2 expression and AD clinical severity or IgE levels were investigated. The wheal reactions in the intracutaneous tests with autologous sweat were positive, weakly positive and negative in 38, 34 and 28% of the AD patients, respectively, and in 4, 46 and 50% of the healthy controls, respectively (p = 0.008). In AD, the wheal reaction was associated significantly with clinical severity, serum total and specific IgE levels and sweat tryptase activity, but not with sweat histamine and chymase. In nonlesional AD skin, the percentage of PAR-2+ mast cells (MCs) or the number of tryptase+ MCs did not differ significantly between the intracutaneous test reactivity groups. Reactivity to autologous sweat correlates with the clinical severity of AD, and tryptase may be one of the factors involved in the sweat-induced wheal. © 2016 S. Karger AG, Basel.

Body map of regional vs. whole body sweating rate and sweat electrolyte concentrations in men and women during moderate exercise-heat stress.

PubMed

Baker, Lindsay B; Ungaro, Corey T; Sopeña, Bridget C; Nuccio, Ryan P; Reimel, Adam J; Carter, James M; Stofan, John R; Barnes, Kelly A

2018-05-01

This study determined the relations between regional (REG) and whole body (WB) sweating rate (RSR and WBSR, respectively) as well as REG and WB sweat Na + concentration ([Na + ]) during exercise. Twenty-six recreational athletes (17 men, 9 women) cycled for 90 min while WB sweat [Na + ] was measured using the washdown technique. RSR and REG sweat [Na + ] were measured from nine regions using absorbent patches. RSR and REG sweat [Na + ] from all regions were significantly ( P < 0.05) correlated with WBSR ( r = 0.58-0.83) and WB sweat [Na + ] ( r = 0.74-0.88), respectively. However, the slope and y-intercept of the regression lines for most models were significantly different than 1 and 0, respectively. The coefficients of determination ( r 2 ) were 0.44-0.69 for RSR predicting WBSR [best predictors: dorsal forearm ( r 2  = 0.62) and triceps ( r 2  = 0.69)] and 0.55-0.77 for REG predicting WB sweat [Na + ] [best predictors: ventral forearm ( r 2  = 0.73) and thigh ( r 2  = 0.77)]. There was a significant ( P < 0.05) effect of day-to-day variability on the regression model predicting WBSR from RSR at most regions but no effect on predictions of WB sweat [Na + ] from REG. Results suggest that REG cannot be used as a direct surrogate for WB sweating responses. Nonetheless, the use of regression equations to predict WB sweat [Na + ] from REG can provide an estimation of WB sweat [Na + ] with an acceptable level of accuracy, especially using the forearm or thigh. However, the best practice for measuring WBSR remains conventional WB mass balance calculations since prediction of WBSR from RSR using absorbent patches does not meet the accuracy or reliability required to inform fluid intake recommendations. NEW & NOTEWORTHY This study developed a body map of regional sweating rate and regional (REG) sweat electrolyte concentrations and determined the effect of within-subject (bilateral and day-to-day) and between-subject (sex) factors on the relations between REG and the whole body (WB). Regression equations can be used to predict WB sweat Na + concentration from REG, especially using the forearm or thigh. However, prediction of WB sweating rate from REG sweating rate using absorbent patches does not reach the accuracy or reliability required to inform fluid intake recommendations.

In vivo sweat film layer thickness measured with Fourier-domain optical coherence tomography (FD-OCT)

NASA Astrophysics Data System (ADS)

Jonathan, Enock

2008-06-01

While human sweat secretion is accepted as a mechanism by which the body cools off, excessive sweating (hyperhidrosis) is now appreciated as a medical condition and the primary site for diagnosis is the palm of the hand. We propose sweat film layer thickness as a potential clinical diagnostic parameter when screening for excessive sweating. In this preliminary study we demonstrate the usefulness of Fourier-domain optical coherence tomography (FD-OCT) for measurement of sweat film thickness in vivo with micron-scale resolution on the hand of a human volunteer. FD-OCT has a superior image acquisition time and identification of active sweat glands, ducts and pores is also possible.

Precise measurement of instantaneous volume of eccrine sweat gland in mental sweating by optical coherence tomography

NASA Astrophysics Data System (ADS)

Sugawa, Yoshihiko; Fukuda, Akihiro; Ohmi, Masato

2015-03-01

We have demonstrated dynamic analysis of the physiological function of eccrine sweat glands underneath skin surface by optical coherence tomography (OCT). We propose a method for extraction of the target eccrine sweat gland by use of the connected component extraction process and the adaptive threshold method, where the en-face OCT images are constructed by the SS-OCT. Furthermore, we demonstrate precise measurement of instantaneous volume of the sweat gland in response to the external stimulus. The dynamic change of instantaneous volume of eccrine sweat gland in mental sweating is performed by this method during the period of 300 sec with the frame intervals of 3.23 sec.

21 CFR 350.50 - Labeling of antiperspirant drug products.

Code of Federal Regulations, 2012 CFR

2012-04-01

... following: “dampness,” “perspiration,” “sweat,” “sweating,” or “wetness”]. (2) The labeling may state “also...: ‘dampness,’ ‘perspiration,’ ‘sweat,’ ‘sweating,’ or ‘wetness’] due to stress”. (3) For products that demonstrate standard effectiveness (20 percent sweat reduction) over a 24-hour period, the labeling may state...

21 CFR 350.50 - Labeling of antiperspirant drug products.

Code of Federal Regulations, 2011 CFR

2011-04-01

... following: “dampness,” “perspiration,” “sweat,” “sweating,” or “wetness”]. (2) The labeling may state “also...: ‘dampness,’ ‘perspiration,’ ‘sweat,’ ‘sweating,’ or ‘wetness’] due to stress”. (3) For products that demonstrate standard effectiveness (20 percent sweat reduction) over a 24-hour period, the labeling may state...

21 CFR 350.50 - Labeling of antiperspirant drug products.

Code of Federal Regulations, 2014 CFR

2014-04-01

... following: “dampness,” “perspiration,” “sweat,” “sweating,” or “wetness”]. (2) The labeling may state “also...: ‘dampness,’ ‘perspiration,’ ‘sweat,’ ‘sweating,’ or ‘wetness’] due to stress”. (3) For products that demonstrate standard effectiveness (20 percent sweat reduction) over a 24-hour period, the labeling may state...

21 CFR 350.50 - Labeling of antiperspirant drug products.

Code of Federal Regulations, 2010 CFR

2010-04-01

... following: “dampness,” “perspiration,” “sweat,” “sweating,” or “wetness”]. (2) The labeling may state “also...: ‘dampness,’ ‘perspiration,’ ‘sweat,’ ‘sweating,’ or ‘wetness’] due to stress”. (3) For products that demonstrate standard effectiveness (20 percent sweat reduction) over a 24-hour period, the labeling may state...

21 CFR 350.50 - Labeling of antiperspirant drug products.

Code of Federal Regulations, 2013 CFR

2013-04-01

... following: “dampness,” “perspiration,” “sweat,” “sweating,” or “wetness”]. (2) The labeling may state “also...: ‘dampness,’ ‘perspiration,’ ‘sweat,’ ‘sweating,’ or ‘wetness’] due to stress”. (3) For products that demonstrate standard effectiveness (20 percent sweat reduction) over a 24-hour period, the labeling may state...

Sweating the small stuff: Glycoproteins in human sweat and their unexplored potential for microbial adhesion.

PubMed

Peterson, Robyn A; Gueniche, Audrey; Adam de Beaumais, Ségolène; Breton, Lionel; Dalko-Csiba, Maria; Packer, Nicolle H

2016-03-01

There is increasing evidence that secretory fluids such as tears, saliva and milk play an important role in protecting the human body from infection via a washing mechanism involving glycan-mediated adhesion of potential pathogens to secretory glycoproteins. Interaction of sweat with bacteria is well established as the cause of sweat-associated malodor. However, the role of sweat glycoproteins in microbial attachment has received little, if any, research interest in the past. In this review, we demonstrate how recent published studies involving high-throughput proteomic analysis have inadvertently, and fortuitously, exposed an abundance of glycoproteins in sweat, many of which have also been identified in other secretory fluids. We bring together research demonstrating microbial adhesion to these secretory glycoproteins in tears, saliva and milk and suggest a similar role of the sweat glycoproteins in mediating microbial attachment to sweat and/or skin. The contribution of glycan-mediated microbial adhesion to sweat glycoproteins, and the associated impact on sweat derived malodor and pathogenic skin infections are unchartered new research areas that we are beginning to explore. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Sex differences in amino acids lost via sweating could lead to differential susceptibilities to disturbances in nitrogen balance and collagen turnover.

PubMed

Dunstan, R H; Sparkes, D L; Dascombe, B J; Stevens, C J; Murphy, G R; Macdonald, M M; Gottfries, J; Gottfries, C-G; Roberts, T K

2017-08-01

Fluid collected during sweating is enriched with amino acids derived from the skin's natural moisturising factors and has been termed "faux" sweat. Little is known about sex differences in sweat amino acid composition or whether faux sweat amino acid losses affect nitrogen balance. Faux sweat collected by healthy adults (n = 47) after exercise, and at rest by chronic fatigue patients, was analysed for amino acid composition. Healthy females had higher total amino acid concentrations in sweat (10.5 ± 1.2 mM) compared with healthy males (6.9 ± 0.9 mM). Females had higher levels of 13 amino acids in sweat including serine, alanine and glycine. Higher hydroxyproline and proline levels suggested greater collagen turnover in females. Modelling indicated that with conservative levels of exercise, amino acid losses in females via faux sweat were triple than those predicted for urine, whereas in males they were double. It was concluded that females were more susceptible to key amino acid loss during exercise and/or hot conditions. Females reporting chronic fatigue had higher levels of methionine in faux sweat than healthy females. Males reporting chronic fatigue had higher levels of numerous amino acids in faux sweat compared to healthy males. Higher amino acid loss in faux sweat associated with chronic fatigue could contribute to a hypometabolic state. Depending on activity levels, climatic conditions and gender, amino acid losses in sweat and skin leachate could influence daily protein turnover where periods of continuously high turnover could lead to a negative net nitrogen balance.

A NEW METHOD OF SWEAT TESTING: THE CF QUANTUM® SWEAT TEST

PubMed Central

Rock, Michael J.; Makholm, Linda; Eickhoff, Jens

2015-01-01

Background Conventional methods of sweat testing are time consuming and have many steps that can and do lead to errors. This study compares conventional sweat testing to a new quantitative method, the CF Quantum® (CFQT) sweat test. This study tests the diagnostic accuracy and analytic validity of the CFQT. Methods Previously diagnosed CF patients and patients who required a sweat test for clinical indications were invited to have the CFQT test performed. Both conventional sweat testing and the CFQT were performed bilaterally on the same day. Pairs of data from each test are plotted as a correlation graph and Bland Altman plot. Sensitivity and specificity were calculated as well as the means and coefficient of variation by test and by extremity. After completing the study, subjects or their parents were asked for their preference of the CFQT and conventional sweat testing. Results The correlation coefficient between the CFQT and conventional sweat testing was 0.98 (95% confidence interval: 0.97–0.99). The sensitivity and specificity of the CFQT in diagnosing CF was 100% (95% confidence interval: 94–100%) and 96% (95% confidence interval: 89–99%), respectively. In one center in this three center multicenter study, there were higher sweat chloride values in patients with CF and also more tests that were invalid due to discrepant values between the two extremities. The percentage of invalid tests was higher in the CFQT method (16.5%) compared to conventional sweat testing (3.8%)(p < 0.001). In the post-test questionnaire, 88% of subjects/parents preferred the CFQT test. Conclusions The CFQT is a fast and simple method of quantitative sweat chloride determination. This technology requires further refinement to improve the analytic accuracy at higher sweat chloride values and to decrease the number of invalid tests. PMID:24862724

Improved Devices for Collecting Sweat for Chemical Analysis

NASA Technical Reports Server (NTRS)

Feeback, Daniel L.; Clarke, Mark S. F.

2011-01-01

Improved devices have been proposed for collecting sweat for biochemical analysis especially for determination of the concentration of Ca2+ ions in sweat as a measure of loss of Ca from bones. Unlike commercially available sweat-collection patches used previously in monitoring osteoporosis and in qualitative screening for some drugs, the proposed devices would not allow evaporation of the volatile chemical components (mostly water) of sweat. Moreover, the proposed devices would be designed to enable determination of the volumes of collected sweat. From these volumes and the quantities of Ca2+ and/or other analytes as determined by other means summarized below, one could determine the concentrations of the analytes in sweat. A device according to the proposal would be flexible and would be worn like a commercial sweat-collection patch. It would be made of molded polydimethylsiloxane (silicone rubber) or other suitable material having properties that, for the purpose of analyzing sweat, are similar to those of glass. The die for molding the silicone rubber would be fabricated by a combination of lithography and electroplating. The die would reproducibly form, in the silicone rubber, a precisely defined number of capillary channels per unit area, each channel having a precisely defined volume. Optionally, electrodes for measuring the Ca2+ content of the sweat could be incorporated into the device. The volume of sweat collected in the capillary channels of the device would be determined from (1) the amount of light or radio waves of a given wavelength absorbed by the device and (2) the known geometry of the array of capillary channels. Then, in one of two options, centrifugation would be performed to move the sweat from the capillary tubes to the region containing the electrodes, which would be used to measure the Ca2+ content by a standard technique. In the other option, centrifugation would be performed to remove the sweat from the device to make the sweat available to other analytical instruments for measuring concentrations of substances other than Ca2+.

Improved Devices for Collecting Sweat for Chemical Analysis

NASA Technical Reports Server (NTRS)

Feedback, Daniel L.; Clarke, Mark S. F.

2011-01-01

Improved devices have been proposed for collecting sweat for biochemical analysis - especially for determination of the concentration of Ca2+ ions in sweat as a measure of loss of Ca from bones. Unlike commercially available sweat-collection patches used previously in monitoring osteoporosis and in qualitative screening for some drugs, the proposed devices would not allow evaporation of the volatile chemical components (mostly water) of sweat. Moreover, the proposed devices would be designed to enable determination of the volumes of collected sweat. From these volumes and the quantities of Ca(2+) and/or other analytes as determined by other means summarized below, one could determine the concentrations of the analytes in sweat. A device according to the proposal would be flexible and would be worn like a commercial sweat-collection patch. It would be made of molded polydimethylsiloxane (silicone rubber) or other suitable material having properties that, for the purpose of analyzing sweat, are similar to those of glass. The die for molding the silicone rubber would be fabricated by a combination of lithography and electroplating. The die would reproducibly form, in the silicone rubber, a precisely defined number of capillary channels per unit area, each channel having a precisely defined volume. Optionally, electrodes for measuring the Ca(2+) content of the sweat could be incorporated into the device. The volume of sweat collected in the capillary channels of the device would be determined from (1) the amount of light or radio waves of a given wavelength absorbed by the device and (2) the known geometry of the array of capillary channels. Then, in one of two options, centrifugation would be performed to move the sweat from the capillary tubes to the region containing the electrodes, which would be used to measure the Ca(2+) content by a standard technique. In the other option, centrifugation would be performed to remove the sweat from the device to make the sweat available to other analytical instruments for measuring concentrations of substances other than Ca(2+).

Laboratory performance of sweat conductivity for the screening of cystic fibrosis.

PubMed

Greaves, Ronda F; Jolly, Lisa; Massie, John; Scott, Sue; Wiley, Veronica C; Metz, Michael P; Mackay, Richard J

2018-03-28

There are several complementary English-language guidelines for the performance of the sweat chloride test. These guidelines also incorporate information for the collection of conductivity samples. However, recommendations for the measurement and reporting of sweat conductivity are less clear than for sweat chloride. The aim of the study was to develop an understanding of the testing and reporting practices of sweat conductivity in Australasian laboratories. A survey specifically directed at conductivity testing was sent to the 12 laboratories registered with the Royal College of Pathologists of Australasia Quality Assurance Programs. Nine (75%) laboratories participated in the survey, seven of whom used Wescor Macroduct® for collecting sweat and the Wescor SWEAT·CHEK™ for conductivity testing, and the remaining two used the Wescor Nanoduct®. There was considerable variation in frequency and staffing for this test. Likewise, criteria about which patients it was inappropriate to test, definitions of adequate collection sweat rate, cutoffs and actions recommended on the basis of the result showed variations between laboratories. Variations in sweat conductivity testing and reporting reflect many of the same issues that were revealed in sweat chloride test audits and have the potential to lead to uncertainty about the result and the proper action in response to the result. We recommend that sweat testing guidelines should include clearer statements about the use of sweat conductivity.

Thin, Soft, Skin-Mounted Microfluidic Networks with Capillary Bursting Valves for Chrono-Sampling of Sweat.

PubMed

Choi, Jungil; Kang, Daeshik; Han, Seungyong; Kim, Sung Bong; Rogers, John A

2017-03-01

Systems for time sequential capture of microliter volumes of sweat released from targeted regions of the skin offer the potential to enable analysis of temporal variations in electrolyte balance and biomarker concentration throughout a period of interest. Current methods that rely on absorbent pads taped to the skin do not offer the ease of use in sweat capture needed for quantitative tracking; emerging classes of electronic wearable sweat analysis systems do not directly manage sweat-induced fluid flows for sample isolation. Here, a thin, soft, "skin-like" microfluidic platform is introduced that bonds to the skin to allow for collection and storage of sweat in an interconnected set of microreservoirs. Pressure induced by the sweat glands drives flow through a network of microchannels that incorporates capillary bursting valves designed to open at different pressures, for the purpose of passively guiding sweat through the system in sequential fashion. A representative device recovers 1.8 µL volumes of sweat each from 0.8 min of sweating into a set of separate microreservoirs, collected from 0.03 cm 2 area of skin with approximately five glands, corresponding to a sweat rate of 0.60 µL min -1 per gland. Human studies demonstrate applications in the accurate chemical analysis of lactate, sodium, and potassium concentrations and their temporal variations. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Characterization of Chemical Constituents of Human Sweat: A Study Based on Indian Population.

PubMed

Moulvi, Aafrinnaz; Minz, Pooja; Rath, Subrata; Ashma, Richa

2018-06-01

There is a strong evidence in the literature that human odor is unique to an individual; therefore, the focus of this study was to strengthen this evidence through the testing of sweat samples on unrelated individuals with the same ethnicity. Sweat samples were collected from 42 unrelated Indian males and females residing in the same city to determine the chemical constituents in human sweat. The volatile compounds of sweat were subsequently analyzed and identified using gas chromatography-mass spectrometry, and a National Institute of Standards and Technology library was used for individual profiling. A total of 78 compounds were identified in human sweat tested with 22 compounds found to be unique to the individual (frequency of occurrence one). A scent profile, or "chexmotype," unique to the sweat of each individual was obtained. This is the first extensive study on an Indian population with 36 new compounds detected in human sweat.

Determination of selected fatty acids in dried sweat spot using gas chromatography with flame ionization detection.

PubMed

Kanďár, Roman; Drábková, Petra; Andrlová, Lenka; Kostelník, Adam; Čegan, Alexander

2016-11-01

A method is described for the determination of fatty acids in dried sweat spot and plasma samples using gas chromatography with flame ionization detection. Plasma and dried sweat spot samples were obtained from a group of blood donors. The sweat was collected from each volunteer during exercise. Sweat was spotted onto collection paper containing butylated hydroxytoluene. Fatty acids were derivatized with acetyl chloride in methanol to form methyl esters of fatty acids. The fatty acids in dried sweat spot samples treated with butylated hydroxytoluene and stored at -20°C were stable for 3 months. Our results indicate that sweat contains, among fatty acids with short chain, also fatty acids with long chain and unsaturated fatty acids. Linear relationships between percentage content of selected fatty acids in dried sweat spot and plasma were observed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

78 FR 41716 - Hours of Service; Limited 90-Day Waiver From the 30-Minute Rest Break Requirement for the...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-11

..., is a significant concern to the agricultural industry. The animals face a variety of stresses... the transportation of pigs because these animals do not sweat and are subject to heat stress. When heat stress occurs, a pig's body temperature rises to a level that it cannot control through its normal...

Evaluating performance in sweat testing in medical biochemistry laboratories in Croatia.

PubMed

Aralica, Merica; Krleza, Jasna Lenicek

2017-02-15

Sweat test has a diagnostic role in evaluation of cystic fibrosis. Its performance includes sweat stimulation, collection and analysis. All listed may be sources of inconsistencies in everyday practice. The aim of this study was an evaluation of external quality assessment (EQA) of sweat chloride measurement including sweat test performance in medical biochemistry laboratories in Croatia. EQA for sweat chloride measurement was provided by Croatian Centre for Quality Assessment in Laboratory Medicine (CROQALM) in five consecutive exercises to medical biochemistry laboratories (MBL) that offered sweat testing. A questionnaire regarding all phases of testing was mailed to involved MBL (N = 10). Survey results were compared to current guidelines for sweat test performance. Reported results of EQA in 2015 exercises showed coefficients of variation (CV) from 28.9%, 29.0% to 35.3%, respectively. An introduction of uniform sweat chloride measurement protocol resulted in CV of 15.5% and 14.7% reported in following two exercises in 2016. All MBL included in this study replied to the questionnaire. Results reported by MBL indicated: lack of patient information policy (7/10), use of unacceptable electrodes (6/9), misuse of minimum of acceptable sweat weight (6/9), lack of internal quality assessment (5/9) and recommended reference ranges (5/9 and 4/9). Agreements to guidelines were found in approach to unsuitable patients (9/10) and sweat collection (8/9). Presented results indicate major weak points of current practice in sweat test performance in Croatian MBL and stress the need for its standardization on a national level.

Evaluating performance in sweat testing in medical biochemistry laboratories in Croatia

PubMed Central

Aralica, Merica; Krleza, Jasna Lenicek

2017-01-01

Introduction Sweat test has a diagnostic role in evaluation of cystic fibrosis. Its performance includes sweat stimulation, collection and analysis. All listed may be sources of inconsistencies in everyday practice. The aim of this study was an evaluation of external quality assessment (EQA) of sweat chloride measurement including sweat test performance in medical biochemistry laboratories in Croatia. Materials and methods EQA for sweat chloride measurement was provided by Croatian Centre for Quality Assessment in Laboratory Medicine (CROQALM) in five consecutive exercises to medical biochemistry laboratories (MBL) that offered sweat testing. A questionnaire regarding all phases of testing was mailed to involved MBL (N = 10). Survey results were compared to current guidelines for sweat test performance. Results Reported results of EQA in 2015 exercises showed coefficients of variation (CV) from 28.9%, 29.0% to 35.3%, respectively. An introduction of uniform sweat chloride measurement protocol resulted in CV of 15.5% and 14.7% reported in following two exercises in 2016. All MBL included in this study replied to the questionnaire. Results reported by MBL indicated: lack of patient information policy (7/10), use of unacceptable electrodes (6/9), misuse of minimum of acceptable sweat weight (6/9), lack of internal quality assessment (5/9) and recommended reference ranges (5/9 and 4/9). Agreements to guidelines were found in approach to unsuitable patients (9/10) and sweat collection (8/9). Conclusion Presented results indicate major weak points of current practice in sweat test performance in Croatian MBL and stress the need for its standardization on a national level. PMID:28392735

Normative data for regional sweat sodium concentration and whole-body sweating rate in athletes.

PubMed

Baker, Lindsay B; Barnes, Kelly A; Anderson, Melissa L; Passe, Dennis H; Stofan, John R

2016-01-01

The purpose of this study was to establish normative data for regional sweat sodium concentration ([Na+]) and whole-body sweating rate in athletes. Data from 506 athletes (367 adults, 139 youth; 404 male, 102 female) were compiled from observational athlete testing for a retrospective analysis. The participants were skill/team-sport (including American football, baseball, basketball, soccer and tennis) and endurance (including cycling, running and triathlon) athletes exercising in cool to hot environmental conditions (15-50 °C) during training or competition in the laboratory or field. A standardised regional absorbent patch technique was used to determine sweat [Na+] on the dorsal mid-forearm. Whole-body sweat [Na+] was predicted using a published regression equation (y = 0.57x+11.05). Whole-body sweating rate was calculated from pre- to post-exercise change in body mass, corrected for fluid/food intake (ad libitum) and urine output. Data are expressed as mean ± SD (range). Forearm sweat [Na+] and predicted whole-body sweat [Na+] were 43.6 ± 18.2 (12.6-104.8) mmol · L(-1) and 35.9 ± 10.4 (18.2-70.8) mmol · L(-1), respectively. Absolute and relative whole-body sweating rates were 1.21 ± 0.68 (0.26-5.73) L · h(-1) and 15.3 ± 6.8 (3.3-69.7) ml · kg(-1) · h(-1), respectively. This retrospective analysis provides normative data for athletes' forearm and predicted whole-body sweat [Na+] as well as absolute and relative whole-body sweating rate across a range of sports and environmental conditions.

Real-time sweat analysis via alternating current conductivity of artificial and human sweat

NASA Astrophysics Data System (ADS)

Liu, Gengchen; Alomari, Mahmoud; Sahin, Bunyamin; Snelgrove, Samuel E.; Edwards, Jeffrey; Mellinger, Axel; Kaya, Tolga

2015-03-01

Dehydration is one of the most profound physiological challenges that significantly affects athletes and soldiers if not detected early. Recently, a few groups have focused on dehydration detection using sweat as the main biomarker. Although there are some proposed devices, the electrical and chemical characteristics of sweat have yet to be incorporated into the validations. In this work, we have developed a simple test setup to analyze artificial sweat that is comprised the main components of human sweat. We provide theoretical and experimental details on the electrical and chemical behavior of the artificial sweat for various concentration values within a temperature range of 5 °C to 50 °C. We have also developed an efficient sweat collecting and detection system based on 3D printing. Human studies were conducted and this particular protocol has shown that dehydration starts to take effect as early as 40 min into the physical activity if there is no fluid intake during the exercise. We believe that our device will lead to developing viable real-time sweat analysis systems.

Prediction of acute pancreatitis risk based on PIP score in children with cystic fibrosis.

PubMed

Terlizzi, V; Tosco, A; Tomaiuolo, R; Sepe, A; Amato, N; Casale, A; Mercogliano, C; De Gregorio, F; Improta, F; Elce, A; Castaldo, G; Raia, V

2014-09-01

Currently no tools to predict risk of acute (AP) and recurrent pancreatitis (ARP) in children with cystic fibrosis (CF) are available. We assessed the prevalence of AP/ARP and tested the potential role of Pancreatic Insufficiency Prevalence (PIP) score in a cohort of children with CF. We identified two groups of children, on the basis of presence/absence of AP/ARP, who were compared for age at diagnosis, clinical features, genotypes and sweat chloride level. PIP score was calculated for each patient. 10/167 (5.9%) experienced at least one episode of AP during follow up; 10/10 were pancreatic sufficient (PS). Patients with AP/ARP showed a PIP score ≤0.25 more frequently (6/10) than patients without AP/ARP. The odds ratio (95% CI) of developing pancreatitis was 4.54 (1.22-16.92) for patients with PIP <0.25 when compared with those who have a PIP score >0.25 (p 0.0151). PIP score was correlated with sweat chloride test (p < 0.01). PIP score, PS status and normal/borderline sweat chloride levels could be applied to predict pancreatitis development in children with CF. ARP could lead to pancreatic insufficiency. Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Satb2-Independent Acquisition of the Cholinergic Sudomotor Phenotype in Rodents

PubMed Central

Schütz, Burkhard; Schaäfer, Martin K.-H.; Gördes, Markus; Eiden, Lee E.; Weihe, Eberhard

2014-01-01

Expression of Satb2 (Special AT-rich sequence-binding protein-2) elicits expression of the vesicular acetylcholine transporter (VAChT) and choline acetyltransferase (ChAT) in cultured rat sympathetic neurons exposed to soluble differentiation factors. Here, we determined whether or not Satb2 plays a similar role in cholinergic differentiation in vivo, by comparing the postnatal profile of Satb2 expression in the rodent stellate ganglion to that of VAChT and ChAT. Throughout postnatal development, VAChT and ChAT were found to be co-expressed in a numerically stable subpopulation of rat stellate ganglion neurons. Nerve fibers innervating rat forepaw sweat glands on P1 were VAChT immunoreactive, while ChAT was detectable at this target only after P5. The postnatal abundance of VAChT transcripts in the stellate ganglion was at maximum already on P1, whereas ChAT mRNA levels increased from low levels on P1 to reach maximum levels between P5 and P21. Satb2 mRNA was detected in cholinergic neurons in the stellate ganglion beginning with P8, thus coincident with the onset of unequivocal detection of ChAT immunoreactivity in forepaw sweat gland endings. Satb2 knockout mice exhibited no change in the P1 cholinergic VAChT/ChAT co-phenotype in stellate ganglion neurons. Thus, cholinergic phenotype maturation involves first, early target (sweat-gland)-independent expression and trafficking of VAChT, and later, potentially target- and Satb2-dependent elevation of ChAT mRNA and protein transport into sweat gland endings. In rat sudomotor neurons that, unlike mouse sudomotor neurons, co-express calcitonin gene-related peptide (CGRP), Satb2 may also be related to the establishment of species-specific neuropeptide co-phenotypes during postnatal development. PMID:25239161

Sweat production during global heating and during isometric exercise in people with diabetes.

PubMed

Petrofsky, Jerrold Scott; Lee, Scott; Patterson, Chris; Cole, Melissa; Stewart, Brian

2005-11-01

While sweat production in response to heat is impaired in people with diabetes, sweat production has not been examined during isometric exercise. Eight subjects with type 2 diabetes and 9 control subjects exerted a fatiguing isometric contraction of the handgrip muscles at a tension of 40% of the maximum voluntary strength (MVC) after exposure to a 32 deg C environment for 30 min. compared to 10 controls and 10 subjects with diabetes exposed to a 39 deg C environment. Sweat was impaired to all areas of the body during heat exposure in patients with diabetes under both environmental conditions. For example, on the chest, the average sweat rates after exposure to the 32 deg environment was 259.2 +/- 55.2 nanoliters/min in control subjects and 198.3 +/- 46.2 nanoliters/min for subjects with diabetes. Compared to the 32 deg C environment, control subjects increased sweat in all 4 areas proportionally more than subjects with diabetes. Sudomotor rhythm was present in sweat in control subjects at a rate of repetition of 11 and 50 seconds but almost absent in subjects with diabetes. During exercise, sweat rates slowly increased from the beginning to the end of the exercise. But the head of the subjects with diabetes showed hypersweating while the other areas showed diminished sweating compared to control subjects. Thus some of the impairment in sweating may be due to central mechanisms associated with heat sensitivity or in the hypothalamus and not to the sweat glands themselves.

Studies on physiological responses of residents in Okinawa to a hot environment.

PubMed

Hori, S; Ihzuka, H; Nakamura, M

1976-01-01

In an attempt to reconfirm Kuno's observation that changes in sweating reaction during long-term heat acclimatization differ from those during short-term heat acclimatization, Ohara's sweating test was performed in summer in Okinawa on 37 male subjects, including 19 residents born and raised in Okinawa (group O) and 18 residents born and raised on one of the main Japanese islands (group M). Seasonal variation of adaptability to heat was also studied in some subjects of both groups. Group O showed significantly less sweat loss, lower Na concentration in sweat and a longer latent period for onset of sweating than group M. Group O showed no seasonal variation in sweat loss, while group M showed considerably greater sweat loss in summer than in winter. In both groups, lower Na concentration in sweat, lower rise in rectal temperature and lesser increase in heart rate in summer than in winter were observed. Seasonal difference in physiological responses of group O to heat exposure was less than that of group M. In conclusion, it was assumed that acclimatization to heat of group O had advanced further than that of group M and this was the reason for longer latent period of sweating and lesser sweat loss in group O in spite of the same rise in rectal temperature in both groups. Discussions were carried out to explain how the sweating pattern and mechanism of acclimatization in group O were different from those in group M.

Sweat Therapy.

ERIC Educational Resources Information Center

Colmant, Stephen A.; Merta, Rod J.

2000-01-01

A study combined group sweating and group counseling. Four adolescent boys with disruptive behavior disorders participated in 12 sweat therapy sessions. They reported the sessions useful for sharing personal concerns and receiving assistance with problem solving. Three boys showed improvement in self-esteem. Advantages of sweat therapy over other…

Exercise-induced trace mineral element concentration in regional versus whole-body wash-down sweat.

PubMed

Baker, Lindsay B; Stofan, John R; Lukaski, Henry C; Horswill, Craig A

2011-06-01

Simultaneous whole-body wash-down (WBW) and regional skin surface sweat collections were completed to compare regional patch and WBW sweat calcium (Ca), magnesium (Mg), copper (Cu), manganese (Mn), iron (Fe), and zinc (Zn) concentrations. Athletes (4 men, 4 women) cycled in a plastic open-air chamber for 90 min in the heat. Before exercise, the subjects and cycle ergometer (covered in plastic) were washed with deionized water. After the onset of sweating, sterile patches were attached to the forearm, back, chest, forehead, and thigh and removed on saturation. After exercise, the subjects and cycle ergometer were washed with 5 L of 15-mM ammonium sulfate solution to collect all sweat minerals and determine the volume of unevaporated sweat. Control trials were performed to measure mineral contamination in regional and WBW methods. Because background contamination in the collection system was high for WBW Mn, Fe, and Zn, method comparisons were not made for these minerals. After correction for minimal background contamination, WBW sweat [Ca], [Mg], and [Cu] were 44.6 ± 20.0, 9.8 ± 4.8, and 0.125 ± 0.069 mg/L, respectively, and 5-site regional (weighted for local sweat rate and body surface area) sweat [Ca], [Mg], and [Cu] were 59.0 ± 15.9, 14.5 ± 4.8, and 0.166 ± 0.031 mg/L, respectively. Five-site regional [Ca], [Mg], and [Cu] overestimated WBW by 32%, 48%, and 33%, respectively. No individual regional patch site or 5-site regional was significantly correlated with WBW sweat [Ca] (r = -.21, p = .65), [Mg] (r = .49, p = .33), or [Cu] (r = .17, p = .74). In conclusion, regional sweat [Ca], [Mg], and [Cu] are not accurate surrogates for or significantly correlated with WBW sweat composition.

Effect of skin temperature on the cholinergic sensitivity of the human eccrine sweat gland.

PubMed

DiPasquale, Dana M; Buono, Michael J; Kolkhorst, Fred W

2003-12-01

Although sweat gland activity is directly controlled by the central nervous system, which detects changes in core body temperature, sweat glands can also be influenced by local cutaneous thermal conditions. The present study sought to determine the effect of local skin temperature on pilocarpine-induced sweating within a range of typical skin temperatures. Thirteen subjects (30 +/- 6 years; 172 +/- 11 cm; 72.8 +/- 11.0 kg) had forearm sweat rates measured at rest following pilocarpine iontophoresis at each of three skin temperatures in randomized order: warm (T(warm) = 37.1 +/- 0.9 degrees C), control (T(con) = 32.3 +/- 1.4 degrees C), and cool (T(cool) = 26.6 +/- 1.3 degrees C). T(skin) was raised and lowered with an electric heating pad and gel ice pack, respectively. Forearm T(skin) was measured with a skin temperature probe. Pilocarpine iontophoresis was used on an approximately 7 cm(2) area of the anterior forearm to stimulate localized sweating. Following stimulation, sweat was collected from the area for 15 min with a Macroduct Sweat Collection System. There was a higher sweat rate at T(warm) (p = 0.001) and T(con) (p = 0.006) compared to that at T(cool). However, there was no difference between the sweat rate at T(warm) and that at T(con) (p = 0.127). These results indicated that skin temperatures below approximately 32 degrees C affect local sweat production primarily by altering glandular sensitivity to the neurotransmitter, whereas skin temperatures above approximately 32 degrees C predominantly affect neurotransmitter release. Furthermore, sweat glands display maximal or near maximal cholinergic sensitivity at resting skin temperature in a thermoneutral environment.

Monitoring cocaine use in substance-abuse-treatment patients by sweat and urine testing.

PubMed

Preston, K L; Huestis, M A; Wong, C J; Umbricht, A; Goldberger, B A; Cone, E J

1999-09-01

Sweat and urine specimens were collected from 44 methadone-maintenance patients to evaluate the use of sweat testing to monitor cocaine use. Paired sweat patches that were applied and removed weekly (on Tuesdays) were compared with 3-5 consecutive urine specimens collected Mondays, Wednesdays, and Fridays. All patches (N = 930) were extracted in 2.5 mL of solvent and analyzed by ELISA immunoassay (cutoff concentration 10 ng/mL); a subset of patches (N = 591) was also analyzed by gas chromatography-mass spectrometry (GC-MS) for cocaine, benzoylecgonine (BZE), and ecgonine methyl ester (EME) (cutoff concentration 5 ng/mL). Urine specimens were subjected to qualitative analysis by EMIT (cutoff 300 ng/mL) and subsets were analyzed by TDx (semiquantitative, LOD 30 ng/mL) and by GC-MS for cocaine (LOD 5 ng/mL). Results were evaluated to (1) determine the relative amounts of cocaine and its metabolites in sweat; (2) assess replicability in duplicate patches; (3) compare ELISA and GC-MS results for cocaine in sweat; and (4) compare the detection of cocaine use by sweat and urine testing. Cocaine was detected by GC-MS in 99% of ELISA-positive sweat patches; median concentrations of cocaine, BZE, and EME were 378, 78.7, and 74 ng/mL, respectively. Agreement in duplicate patches was approximately 90% by ELISA analysis. The sensitivity, specificity, and efficiency of sweat ELISA cocaine results as compared with sweat GC-MS results were 93.6%, 91.3%, and 93.2%, respectively. The sensitivity, specificity, and efficiency between ELISA sweat patch and EMIT urine results were 97.6%, 60.5%, and 77.7%, respectively. These results support the use of sweat patches for monitoring cocaine use, though further evaluation is needed.

Effect of sweating set rate on clothing real evaporative resistance determined on a sweating thermal manikin in a so-called isothermal condition (T manikin = T a = T r).

PubMed

Lu, Yehu; Wang, Faming; Peng, Hui; Shi, Wen; Song, Guowen

2016-04-01

The ASTM F2370 (2010) is the only standard with regard to measurement of clothing real evaporative resistance by means of a sweating manikin. However, the sweating set-point is not recommended in the standard. In this study, the effect of sweating rate on clothing real evaporative resistance was investigated on a 34-zone "Newton" sweating thermal manikin in a so-called isothermal condition (T manikin = T a = T r). Four different sweating set rates (i.e., all segments had a sweating rate of 400, 800, 1200 ml/hr ∙ m(2), respectively, and different sweating rates were assigned to different segments) were applied to determine the clothing real evaporative resistance of five clothing ensembles and the boundary air layer. The results indicated that the sweating rate did not affect the real evaporative resistance of clothing ensembles with the absence of strong moisture absorbent layers. For the clothing ensemble with tight cotton underwear, a sweating rate of lower than 400 ml/hr ∙ m(2) is not recommended. This is mainly because the wet fabric "skin" might not be fully saturated and thus led to a lower evaporative heat loss and thereby a higher real evaporative resistance. For vapor permeable clothing, the real evaporative resistance determined in the so-called isothermal condition should be corrected before being used in thermal comfort or heat strain models. However, the reduction of wet thermal insulation due to moisture absorption in different test scenarios had a limited contribution to the effect of sweating rate on the real evaporative resistance.

Three-dimensional cell shapes and arrangements in human sweat glands as revealed by whole-mount immunostaining

PubMed Central

Kurata, Ryuichiro; Futaki, Sugiko; Nakano, Itsuko; Fujita, Fumitaka; Tanemura, Atsushi; Murota, Hiroyuki; Katayama, Ichiro; Okada, Fumihiro

2017-01-01

Because sweat secretion is facilitated by mechanical contraction of sweat gland structures, understanding their structure-function relationship could lead to more effective treatments for patients with sweat gland disorders such as heat stroke. Conventional histological studies have shown that sweat glands are three-dimensionally coiled tubular structures consisting of ducts and secretory portions, although their detailed structural anatomy remains unclear. To better understand the details of the three-dimensional (3D) coiled structures of sweat glands, a whole-mount staining method was employed to visualize 3D coiled gland structures with sweat gland markers for ductal luminal, ductal basal, secretory luminal, and myoepithelial cells. Imaging the 3D coiled gland structures demonstrated that the ducts and secretory portions were comprised of distinct tubular structures. Ductal tubules were occasionally bent, while secretory tubules were frequently bent and formed a self-entangled coiled structure. Whole-mount staining of complex coiled gland structures also revealed the detailed 3D cellular arrangements in the individual sweat gland compartments. Ducts were composed of regularly arranged cuboidal shaped cells, while secretory portions were surrounded by myoepithelial cells longitudinally elongated along entangled secretory tubules. Whole-mount staining was also used to visualize the spatial arrangement of blood vessels and nerve fibers, both of which facilitate sweat secretion. The blood vessels ran longitudinally parallel to the sweat gland tubules, while nerve fibers wrapped around secretory tubules, but not ductal tubules. Taken together, whole-mount staining of sweat glands revealed the 3D cell shapes and arrangements of complex coiled gland structures and provides insights into the mechanical contraction of coiled gland structures during sweat secretion. PMID:28636607

How are the ancient cystic fibrosis patients? Cystic fibrosis diagnosed over 60 years-old.

PubMed

Prados, C; Lerín, M; Cabanillas, J J; Gómez-Carrera, L; Álvarez-Sala, R

2017-01-01

To specify the prevalence of patients diagnosed with CF at age of ≥60 year-old and to analyze their characteristics. Observational study of CF patients which were diagnosed at age ≥60 year-old. The analyzed variables were: age, sex, nationality, lung function parameters, conditions present at diagnosis, microbiological characteristics and genetic findings. eight patients were included. 7 patients were female (87.5%) with a mean age of 70.6 years (median 71.5 years, range 60-78 years). The most important findings were: sweat test >60 mEq/l; heterozygotes F508del; bronchiectasis in CT; methicillin-sensitive Staphylococcus aureus (50%) in sputum. The most patients presented a normal or mild obstructive lung function. CF must also be considered a disease diagnosed in adulthood, incorporating the sweat test within the usual techniques of differential diagnosis in patients with different diseases associated with CF, because genetic counselling is esencial.

A new method of sweat testing: the CF Quantum®sweat test.

PubMed

Rock, Michael J; Makholm, Linda; Eickhoff, Jens

2014-09-01

Conventional methods of sweat testing are time consuming and have many steps that can and do lead to errors. This study compares conventional sweat testing to a new quantitative method, the CF Quantum® (CFQT) sweat test. This study tests the diagnostic accuracy and analytic validity of the CFQT. Previously diagnosed CF patients and patients who required a sweat test for clinical indications were invited to have the CFQT test performed. Both conventional sweat testing and the CFQT were performed bilaterally on the same day. Pairs of data from each test are plotted as a correlation graph and Bland-Altman plot. Sensitivity and specificity were calculated as well as the means and coefficient of variation by test and by extremity. After completing the study, subjects or their parents were asked for their preference of the CFQT and conventional sweat testing. The correlation coefficient between the CFQT and conventional sweat testing was 0.98 (95% confidence interval: 0.97-0.99). The sensitivity and specificity of the CFQT in diagnosing CF was 100% (95% confidence interval: 94-100%) and 96% (95% confidence interval: 89-99%), respectively. In one center in this three center multicenter study, there were higher sweat chloride values in patients with CF and also more tests that were invalid due to discrepant values between the two extremities. The percentage of invalid tests was higher in the CFQT method (16.5%) compared to conventional sweat testing (3.8%) (p < 0.001). In the post-test questionnaire, 88% of subjects/parents preferred the CFQT test. The CFQT is a fast and simple method of quantitative sweat chloride determination. This technology requires further refinement to improve the analytic accuracy at higher sweat chloride values and to decrease the number of invalid tests. Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

A Little CFTR Goes a Long Way: CFTR-Dependent Sweat Secretion from G551D and R117H-5T Cystic Fibrosis Subjects Taking Ivacaftor

PubMed Central

Char, Jessica E.; Wolfe, Marlene H.; Cho, Hyung-ju; Park, Il-Ho; Jeong, Jin Hyeok; Frisbee, Eric; Dunn, Colleen; Davies, Zoe; Milla, Carlos; Moss, Richard B.; Thomas, Ewart A. C.; Wine, Jeffrey J.

2014-01-01

To determine if oral dosing with the CFTR-potentiator ivacaftor (VX-770, Kalydeco) improves CFTR-dependent sweating in CF subjects carrying G551D or R117H-5T mutations, we optically measured sweat secretion from 32–143 individually identified glands in each of 8 CF subjects; 6 F508del/G551D, one G551D/R117H-5T, and one I507del/R117H-5T. Two subjects were tested only (−) ivacaftor, 3 only (+) ivacaftor and 3 (+/−) ivacaftor (1–5 tests per condition). The total number of gland measurements was 852 (−) ivacaftor and 906 (+) ivacaftor. A healthy control was tested 4 times (51 glands). For each gland we measured both CFTR-independent (M-sweat) and CFTR-dependent (C-sweat); C-sweat was stimulated with a β-adrenergic cocktail that elevated [cAMP]i while blocking muscarinic receptors. Absent ivacaftor, almost all CF glands produced M-sweat on all tests, but only 1/593 glands produced C-sweat (10 tests, 5 subjects). By contrast, 6/6 subjects (113/342 glands) produced C-sweat in the (+) ivacaftor condition, but with large inter-subject differences; 3–74% of glands responded with C/M sweat ratios 0.04%–2.57% of the average WT ratio of 0.265. Sweat volume losses cause proportionally larger underestimates of CFTR function at lower sweat rates. The losses were reduced by measuring C/M ratios in 12 glands from each subject that had the highest M-sweat rates. Remaining losses were estimated from single channel data and used to correct the C/M ratios, giving estimates of CFTR function (+) ivacaftor  = 1.6%–7.7% of the WT average. These estimates are in accord with single channel data and transcript analysis, and suggest that significant clinical benefit can be produced by low levels of CFTR function. PMID:24520399

Sweat output measurement of the post-ganglion sudomotor response by Q-Sweat Test: a normative database of Chinese individuals

PubMed Central

2012-01-01

Background Q-Sweat is a model used for evaluating the post-ganglionic sudomotor function by assessing sweat response. This study aimed to establish the normative database of Q-Sweat test among Chinese individuals since this type of information is currently lacking. Results One hundred and fifty (150) healthy volunteers, 76 men and 74 women with age range of 22–76 years were included. Skin temperature and sweat onset latency measured at the four sites (i.e., the forearm, proximal leg, distal leg, and the foot) did not significantly correlate with age, gender, body height (BH), body weight (BW), and body mass index (BMI) but the total sweat volume measured in all four sites significantly correlated with sex, BH, and BW. Except for the distal leg, the total sweat volume measured at the other three sites had a significant correlation with BMI. In terms of gender, men had larger total sweat volume, with median differences at the forearm, proximal leg, distal leg, and foot of 0.591 μl, 0.693 μl, 0.696 μl, and 0.358 μl, respectively. Regarding BW difference (≥62 and < 62 Kg), those with BW ≥62 Kg had larger total sweat volume. Median differences at the forearm, proximal leg, distal leg, and foot were 0.538 μl, 0.744 μl, 0.695 μl, and 0.338 μl, respectively. There was an uneven distribution of male and female participants in the two BW groups. In all conditions, the total sweat volume recorded at the foot site was the smallest. Conclusion This is the first report to show the normative database of sweat response in Chinese participants evaluated using Q-Sweat device. This normative database can help guide further research on post-ganglionic sudomotor or related clinical practice involving a Chinese population. PMID:22682097

Chloride and sodium ion concentrations in saliva and sweat as a method to diagnose cystic fibrosis.

PubMed

Gonçalves, Aline Cristina; Marson, Fernando Augusto Lima; Mendonça, Regina Maria Holanda; Bertuzzo, Carmen Sílvia; Paschoal, Ilma Aparecida; Ribeiro, José Dirceu; Ribeiro, Antônio Fernando; Levy, Carlos Emílio

2018-05-19

Cystic fibrosis diagnosis is dependent on the chloride ion concentration in the sweat test (≥60mEq/mL - recognized as the gold standard indicator for cystic fibrosis diagnosis). Moreover, the salivary glands express the CFTR protein in the same manner as sweat glands. Given this context, the objective was to verify the correlation of saliva chloride concentration and sweat chloride concentration, and between saliva sodium concentration and sweat sodium concentration, in patients with cystic fibrosis and healthy control subjects, as a tool for cystic fibrosis diagnosis. There were 160 subjects enrolled: 57/160 (35.70%) patients with cystic fibrosis and two known CFTR mutations and 103/160 (64.40%) healthy controls subjects. Saliva ion concentration was analyzed by ABL 835 Radiometer ® equipment and, sweat chloride concentration and sweat sodium concentration, respectively, by manual titration using the mercurimetric procedure of Schales & Schales and flame photometry. Statistical analysis was performed by the chi-squared test, the Mann-Whitney test, and Spearman's correlation. Alpha=0.05. Patients with cystic fibrosis showed higher values of sweat chloride concentration, sweat sodium concentration, saliva chloride concentration, and saliva sodium concentration than healthy controls subjects (p-value<0.001). The correlation between saliva chloride concentration and sweat chloride concentration showed a positive Spearman's Rho (correlation coefficient)=0.475 (95% CI=0.346 to 0.587). Also, the correlation between saliva sodium concentration and sweat sodium concentration showed a positive Spearman's Rho=0.306 (95% CI=0.158 to 0.440). Saliva chloride concentration and saliva sodium concentration are candidates to be used in cystic fibrosis diagnosis, mainly in cases where it is difficult to achieve the correct sweat amount, and/or CFTR mutation screening is difficult, and/or reference methods for sweat test are unavailable to implement or are not easily accessible by the general population. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Acquired defects in CFTR-dependent β-adrenergic sweat secretion in chronic obstructive pulmonary disease

PubMed Central

2014-01-01

Rationale Smoking-induced chronic obstructive pulmonary disease (COPD) is associated with acquired systemic cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction. Recently, sweat evaporimetry has been shown to efficiently measure β-adrenergic sweat rate and specifically quantify CFTR function in the secretory coil of the sweat gland. Objectives To evaluate the presence and severity of systemic CFTR dysfunction in smoking-related lung disease using sweat evaporimetry to determine CFTR-dependent sweat rate. Methods We recruited a cohort of patients consisting of healthy never smokers (N = 18), healthy smokers (12), COPD smokers (25), and COPD former smokers (12) and measured β-adrenergic sweat secretion rate with evaporative water loss, sweat chloride, and clinical data (spirometry and symptom questionnaires). Measurements and main results β-adrenergic sweat rate was reduced in COPD smokers (41.9 ± 3.4, P < 0.05, ± SEM) and COPD former smokers (39.0 ± 5.4, P < 0.05) compared to healthy controls (53.6 ± 3.4). Similarly, sweat chloride was significantly greater in COPD smokers (32.8 ± 3.3, P < 0.01) and COPD former smokers (37.8 ± 6.0, P < 0.01) vs. healthy controls (19.1 ± 2.5). Univariate analysis revealed a significant association between β-adrenergic sweat rate and female gender (β = 0.26), age (−0.28), FEV1% (0.35), dyspnea (−0.3), and history of smoking (−0.27; each P < 0.05). Stepwise multivariate regression included gender (0.39) and COPD (−0.43) in the final model (R2 = 0.266, P < 0.0001). Conclusions β-adrenergic sweat rate was significantly reduced in COPD patients, regardless of smoking status, reflecting acquired CFTR dysfunction and abnormal gland secretion in the skin that can persist despite smoking cessation. β-adrenergic sweat rate and sweat chloride are associated with COPD severity and clinical symptoms, supporting the hypothesis that CFTR decrements have a causative role in COPD pathogenesis. PMID:24568560

Increase in dermcidin-derived peptides in sweat of patients with atopic eczema caused by a humorous video.

PubMed

Kimata, Hajime

2007-01-01

Dermcidin (DCD)-derived peptide is an antimicrobial peptide produced by the sweat glands. However, the levels of DCD-derived peptide in sweat were decreased in patients with atopic eczema (AE). The effect of viewing a humorous video on the levels of DCD-derived peptide was studied. Twenty patients with AE viewed an 87-min humorous video (Modern Times, featuring Charlie Chaplin). Just before and immediately after viewing, sweat was collected, and the levels of DCD-derived peptide and total protein in sweat were measured. Viewing a humorous video increased the levels of DCD-derived peptide without affecting the levels of total protein in sweat. Viewing a humorous video increased DCD-derived peptide in sweat of patients with AE, and thus, it may be helpful in the treatment of skin infection of AE.

Endocrine concomitants of sweating and sweat depression.

PubMed

Candas, V; Brandenberger, G; Lutz-Bucher, B; Follenius, M; Libert, J P

1984-01-01

The effect of humid heat (Ta = 43 degrees C, Pa = 32 Torr) on sweat rate, plasma renin activity and plasma levels of aldosterone and antidiuretic hormone (ADH) was studied in four male subjects before and after repeated heat exposures. Over-sweating and sweat drippage followed by hidromeiosis were observed in three subjects during initial heat exposure. With repeated humid heat exposures increased sweat rates were accompanied by a more intense sweat depression (hidromeiosis) in all four subjects. In our conditions, no changes in plasma levels of aldosterone and ADH or plasma renin activity were observed with hidromeiosis. Plasma renin activity was slightly depressed by repeated exposures, whereas plasma volumes were enhanced, with no significant changes in plasma Na or K. The results suggest that neither ADH nor the components of the renin-angiotensin aldosterone system are involved in the hidromeiotic phenomenon.

A Method to Estimate Fabric Particle Penetration Performance

DTIC Science & Technology

2014-09-08

may be needed to improve the correlation between wind tunnel component sleeve tests and bench top swatch test. The ability to predict multi-layered...within the fabric/component gap may be needed to improve the correlation between wind tunnel component sleeve tests and bench top swatch test...impermeable garment . Heat stress becomes a major problem with this approach however, as normal physiological heat loss mechanisms (especially sweat

Sixty-five years since the New York heat wave: advances in sweat testing for cystic fibrosis.

PubMed

Collie, Jake T B; Massie, R John; Jones, Oliver A H; LeGrys, Vicky A; Greaves, Ronda F

2014-02-01

The sweat test remains important as a diagnostic test for cystic fibrosis (CF) and has contributed greatly to our understanding of CF as a disease of epithelial electrolyte transport. The standardization of the sweat test, by Gibson and Cooke [Gibson and Cooke (1959) Pediatrics 1959;23:5], followed observations of excessive dehydration amongst patients with CF and confirmed the utility as a diagnostic test. Quantitative pilocarpine iontophoresis remains the gold standard for sweat induction, but there are a number of collection and analytical methods. The pathophysiology of electrolyte transport in sweat was described by Quinton [Quinton (1983) Nature 1983;301:421-422], and this complemented the developments in genetics that discovered the cystic fibrosis transmembrane conductance regulator (CFTR), an epithelial-based electrolyte transport protein. Knowledge of CF has since increased rapidly and further developments in sweat testing include: new collection methods, further standardization of the technique with international recommendations and age related reference intervals. More recently, sweat chloride values have been used as proof of effect for the new drugs that activate CFTR. However, there remain issues with adherence to sweat test guidelines in many countries and there are gaps in our knowledge, including reference intervals for some age groups and stability of sweat samples in transport. Furthermore, modern methods of elemental quantification need to be explored as alternatives to the original analytical methods for sweat electrolyte measurement. The purpose of this review is therefore to describe the development of the sweat test and consider future directions. © 2013 Wiley Periodicals, Inc.

Sweat lipid mediator profiling: a non-invasive approach for cutaneous research

USDA-ARS?s Scientific Manuscript database

Sweat is a complex biological fluid with potential diagnostic value for the investigation of skin disorders. Previous efforts in sweat testing focused on analysis of small molecules and ions for forensic and diagnostic testing, but with advances in analytical and sweat collection techniques, there h...

Diagnosing night sweats.

PubMed

Viera, Anthon J; Bond, Michael M; Yates, Scott W

2003-03-01

Night sweats are a common outpatient complaint, yet literature on the subject is scarce. Tuberculosis and lymphoma are diseases in which night sweats are a dominant symptom, but these are infrequently found to be the cause of night sweats in modern practice. While these diseases remain important diagnostic considerations in patients with night sweats, other diagnoses to consider include human immunodeficiency virus, gastroesophageal reflux disease, obstructive sleep apnea, hyperthyroidism, hypoglycemia, and several less common diseases. Antihypertensives, antipyretics, other medications, and drugs of abuse such as alcohol and heroin may cause night sweats. Serious causes of night sweats can be excluded with a thorough history, physical examination, and directed laboratory and radiographic studies. If a history and physical do not reveal a possible diagnosis, physicians should consider a purified protein derivative, complete blood count, human immunodeficiency virus test, thyroid-stimulating hormone test, erythrocyte sedimentation rate evaluation, chest radiograph, and possibly chest and abdominal computed tomographic scans and bone marrow biopsy.

Sweat Chlorides in Salt-Deprived Cystic Fibrosis Heterozygotes

PubMed Central

Myers, Michael F.

1965-01-01

Sweat chlorides of 10 sets of parents of children with cystic fibrosis and 11 controls were studied in an attempt to develop a test for the diagnosis of cystic fibrosis heterozygotes by subjecting both the parents and controls to a low sodium diet and comparing sweat chloride values as the diet progressed. It was hoped that the sweat chloride levels of the parents, the heterozygotes, would remain stationary throughout the diet, since their children, the homozygotes, reveal this finding under similar conditions of salt deprivation. The sweat chloride levels of the controls, because of effects of aldosterone, were expected to decrease steadily from the commencement of the diet to its termination. A decrease in sweat chloride values of similar magnitude was found in both parents and controls as the diet continued. It is concluded that the study of sweat electrolyte levels in salt-deprived subjects is of no value in the diagnosis of cystic fibrosis heterozygotes. PMID:14289142

Mechanisms of thermal acclimation to exercise and heat

NASA Technical Reports Server (NTRS)

Nadel, E. R.; Pandolf, K. B.; Roberts, M. F.; Stolwijk, J. A. J.

1974-01-01

By plotting local sweating rate from a given area against the central sweating drive (which is analogous to esophageal temperature, when mean skin temperature is constant), it is possible to determine the characteristic gain constant of that area as well as its point of zero central drive. An increase in the gain constant as a result of acclimation would indicate an increased sensitivity of the sweating mechanism per unit of central sweating drive, i.e., enhanced peripheral sensitivity. A displacement of the point of zero central drive as a result of acclimation would indicate that central mechanisms are responsible for the heightened sweating response. The study was undertaken to provide information about whether central or peripheral physiological mechanisms provide for increased sweating capabilities during acclimation, and about whether the increased sweating capabilities in heat acclimation and physical training are provided for by the same mechanisms.

Effects of stimulation technique, anatomical region and time on human sweat lipid mediator profiles.

USDA-ARS?s Scientific Manuscript database

Few studies compare sampling protocol effect on sweat composition. Here we evaluate the impact of sweat stimulation mode and site of collection on lipid mediator composition. Sweat from healthy males (n = 7) was collected weekly for three weeks from the volar forearm following either pilocarpine ion...

Sweat Therapy Theory, Practice, and Efficacy

ERIC Educational Resources Information Center

Eason, Allen; Colmant, Stephen; Winterowd, Carrie

2009-01-01

The purpose of this article is to examine the potential application of sweat rituals to group counseling, adventure therapy, and other forms of group work by describing a theoretical model for how sweat rituals work and presenting the results of a randomized comparative outcome study on the efficacy of sweat therapy. The theoretical model proposes…

78 FR 57650 - Announcement of Funding Awards for the Self-Help Homeownership Opportunity Program (SHOP) for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-19

... significant amount of sweat equity towards the development of the SHOP units. Sweat equity involves... SHOP funds together with the homebuyer's sweat equity and volunteer labor contributions significantly... sweat equity contribution must not be mortgaged or otherwise restricted upon future sale of the SHOP...

40 CFR 63.1506 - Operating requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... an existing sweat furnace that meets the specifications of § 63.1505(f)(1) must operate the sweat... date of this standard. (3) The owner or operator of a new sweat furnace that meets the specifications of § 63.1505(f)(1) must operate the sweat furnace and control equipment according to the requirements...

40 CFR 63.1506 - Operating requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... an existing sweat furnace that meets the specifications of § 63.1505(f)(1) must operate the sweat... date of this standard. (3) The owner or operator of a new sweat furnace that meets the specifications of § 63.1505(f)(1) must operate the sweat furnace and control equipment according to the requirements...

Crying for a Vision: The Native American Sweat Lodge Ceremony as Therapeutic Intervention

ERIC Educational Resources Information Center

Garrett, Michael Tlanusta; Torres-Rivera, Edil; Brubaker, Michael; Portman, Tarrell Awe Agahe; Brotherton, Dale; West-Olatunji, Cirecie; Conwill, William; Grayshield, Lisa

2011-01-01

The Native American sweat lodge ceremony or sweat therapy is being used increasingly in various medical, mental health, correctional, and substance abuse treatment centers serving both Native and non-Native clients. This article explores the sweat lodge ceremony's background, elements of Native American spirituality, origin story, cultural…

Congenital hypotrichosis in a Percheron draught horse.

PubMed

Valentine, B A; Hedstrom, O R; Miller, W H; Scott, D W; Mathies, S

2001-08-01

A blue roan Percheron foal was born with poorly circumscribed patchy alopecia of the trunk and legs. Teeth and hoof development were normal. Alopecia was progressive, becoming almost complete by 1 year of age. Histopathological findings in a skin biopsy obtained at 7 months of age were consistent with severe follicular hypoplasia. Sebaceous glands, epitrichial sweat glands and arrector pilae muscles were normal. The horse is alive and otherwise well at 6 years of age, although adult stature is considered small for this breed. The clinical history and histopathological findings are most consistent with a form of congenital hypotrichosis.

A distinct type of hidrotic ectodermal dysplasia.

PubMed

Halal, F; Setton, N; Wang, N S

1991-03-15

Four individuals from 2 generations of a family had a hidrotic type of ectodermal dysplasia (ED). Males and females were similarly affected. They had trichodysplasia, with absent eyebrows and eyelashes; normal teeth, onychodysplasia; normal sweating; mild retrognathia; abnormal dermatoglyphics; and mental retardation. Additional variable manifestations included irregular menses, high implanted or prominent ears, café-au-lait spot, keratosis pilaris, supernumerary nipple, and mild hearing loss. Their previously undescribed condition could be classified as an ED of 1-3 (trichoonychial) subgroup of group A according to Freire-Maia's classification and is inherited as an autosomal recessive trait.

The microfluidics of the eccrine sweat gland, including biomarker partitioning, transport, and biosensing implications

PubMed Central

Sonner, Z.; Wilder, E.; Heikenfeld, J.; Kasting, G.; Beyette, F.; Swaile, D.; Sherman, F.; Joyce, J.; Hagen, J.; Kelley-Loughnane, N.; Naik, R.

2015-01-01

Non-invasive and accurate access of biomarkers remains a holy grail of the biomedical community. Human eccrine sweat is a surprisingly biomarker-rich fluid which is gaining increasing attention. This is especially true in applications of continuous bio-monitoring where other biofluids prove more challenging, if not impossible. However, much confusion on the topic exists as the microfluidics of the eccrine sweat gland has never been comprehensively presented and models of biomarker partitioning into sweat are either underdeveloped and/or highly scattered across literature. Reported here are microfluidic models for eccrine sweat generation and flow which are coupled with review of blood-to-sweat biomarker partition pathways, therefore providing insights such as how biomarker concentration changes with sweat flow rate. Additionally, it is shown that both flow rate and biomarker diffusion determine the effective sampling rate of biomarkers at the skin surface (chronological resolution). The discussion covers a broad class of biomarkers including ions (Na+, Cl−, K+, NH4+), small molecules (ethanol, cortisol, urea, and lactate), and even peptides or small proteins (neuropeptides and cytokines). The models are not meant to be exhaustive for all biomarkers, yet collectively serve as a foundational guide for further development of sweat-based diagnostics and for those beginning exploration of new biomarker opportunities in sweat. PMID:26045728

Effects of high and low blood lactate concentrations on sweat lactate response.

PubMed

Green, J M; Bishop, P A; Muir, I H; McLester, J R; Heath, H E

2000-11-01

Sweat lactate results from eccrine gland metabolism, however, the possible clearance of blood lactate through sweat has not been resolved. On separate days in an environmental chamber (32 +/- 1 C) 12 subjects completed a constant load (CON) (30 min at 40% VO2 max) and an interval cycling trial (INT) (15 one-min intervals at 80% VO2 max, each separated by one min rest) each designed to elicit different blood lactate responses. Each 30 min cycling trial was preceded by 15 min warm-up (30 watts) and followed by 15 min passive rest. Sweat and blood were analyzed for lactate concentration at 15, 25, 35, 45, and 60 min during CON and INT. Total body water loss was used to calculate sweat rate (ml/hr). Blood lactate was significantly greater (p < or = 0.05) at 25, 35, 45, and 60 min during INT compared to CON (approximately 5 mmol/L vs 1.5 mmol/L). Sweat lactate was not significantly different (p>0.05) between trials at any time (approximately 10 mmol/L). Sweat rates (approximately 600ml/hr) and estimated total lactate secretion were not significantly different (CON vs. INT) (p > 0.05). Elevated blood lactate was not associated with changes in sweat lactate concentration. Sweat lactate seems to originate in eccrine glands independent of blood lactate.

Comparison of fabric skins for the simulation of sweating on thermal manikins

NASA Astrophysics Data System (ADS)

Koelblen, Barbara; Psikuta, Agnes; Bogdan, Anna; Annaheim, Simon; Rossi, René M.

2017-09-01

Sweating is an important thermoregulatory process helping to dissipate heat and, thus, to prevent overheating of the human body. Simulations of human thermo-physiological responses in hot conditions or during exercising are helpful for assessing heat stress; however, realistic sweating simulation and evaporative cooling is needed. To this end, thermal manikins dressed with a tight fabric skin can be used, and the properties of this skin should help human-like sweat evaporation simulation. Four fabrics, i.e., cotton with elastane, polyester, polyamide with elastane, and a skin provided by a manikin manufacturer (Thermetrics) were compared in this study. The moisture management properties of the fabrics have been investigated in basic tests with regard to all phases of sweating relevant for simulating human thermo-physiological responses, namely, onset of sweating, fully developed sweating, and drying. The suitability of the fabrics for standard tests, such as clothing evaporative resistance measurements, was evaluated based on tests corresponding to the middle phase of sweating. Simulations with a head manikin coupled to a thermo-physiological model were performed to evaluate the overall performance of the skins. The results of the study showed that three out of four evaluated fabrics have adequate moisture management properties with regard to the simulation of sweating, which was confirmed in the coupled simulation with the head manikin. The presented tests are helpful for comparing the efficiency of different fabrics to simulate sweat-induced evaporative cooling on thermal manikins.

Relationships between micronutrient losses in sweat and blood pressure among heat-exposed steelworkers.

PubMed

Tang, Yong-Mei; Wang, Dao-Gang; Li, Jun; Li, Xing-Hua; Wang, Qian; Liu, Nan; Liu, Wei-Tian; Li, Ying-Xue

2016-06-10

We aimed to examine the effect of micronutrient losses through sweat on blood pressure (BP) among heat-exposed steelworkers. A total of 224 heat-exposed male steelworkers from an ironworks facility were evaluated in July 2012. We measured the Wet Bulb Globe Temperature Index to evaluate the level of heat stress in the workplace. We collected sweat from the workers during an eight-hour work, and then we measured the micronutrients in the sweat. We also measured the BP of each worker. The results revealed that vitamin C, potassium, and calcium losses in sweat were positively correlated with systolic (SBP) and diastolic (DBP) blood pressure (all P<0.05). A linear stepwise regression analysis revealed that potassium, and calcium losses in sweat adversely affected SBP and DBP (all P<0.05). An analysis of covariance showed that SBP increased when potassium or calcium losses in sweat were >900 mg, or >100 mg, respectively. Further, DBP increased when potassium or calcium losses in sweat were >600 mg or >130 mg, respectively. Therefore, vitamin C, potassium, and calcium losses in sweat may adversely effect BP. To help steelworkers maintain healthy BP, facilities with high temperatures should try to lower environmental temperatures to reduce vitamin C, potassium, and calcium losses in sweat. Additionally, heat-exposed steelworkers may need to increase their dietary intakes of vitamin C, potassium, and calcium. Further research is needed to confirm these findings and support these recommendations.

Relationships between micronutrient losses in sweat and blood pressure among heat-exposed steelworkers

PubMed Central

TANG, Yong-Mei; WANG, Dao-Gang; LI, Jun; LI, Xing-Hua; WANG, Qian; LIU, Nan; LIU, Wei-Tian; LI, Ying-Xue

2016-01-01

We aimed to examine the effect of micronutrient losses through sweat on blood pressure (BP) among heat-exposed steelworkers. A total of 224 heat-exposed male steelworkers from an ironworks facility were evaluated in July 2012. We measured the Wet Bulb Globe Temperature Index to evaluate the level of heat stress in the workplace. We collected sweat from the workers during an eight-hour work, and then we measured the micronutrients in the sweat. We also measured the BP of each worker. The results revealed that vitamin C, potassium, and calcium losses in sweat were positively correlated with systolic (SBP) and diastolic (DBP) blood pressure (all P<0.05). A linear stepwise regression analysis revealed that potassium, and calcium losses in sweat adversely affected SBP and DBP (all P<0.05). An analysis of covariance showed that SBP increased when potassium or calcium losses in sweat were >900 mg, or >100 mg, respectively. Further, DBP increased when potassium or calcium losses in sweat were >600 mg or >130 mg, respectively. Therefore, vitamin C, potassium, and calcium losses in sweat may adversely effect BP. To help steelworkers maintain healthy BP, facilities with high temperatures should try to lower environmental temperatures to reduce vitamin C, potassium, and calcium losses in sweat. Additionally, heat-exposed steelworkers may need to increase their dietary intakes of vitamin C, potassium, and calcium. Further research is needed to confirm these findings and support these recommendations. PMID:27087421

Efficient sweat reduction of three different antiperspirant application forms during stress-induced sweating.

PubMed

Schmidt-Rose, T; Lehmbeck, F; Bürger, A; Windisch, B; Keyhani, R; Max, H

2013-12-01

Stress sweating can occur in everyday situations independently of thermally-induced perspiration. It is triggered by emotionally challenging situations and leads to underarm wetness and a characteristic unpleasant malodor. In this study, we aimed to determine the long-term efficacy of three unperfumed antiperspirant (AP) formulas for different application forms (roll-on, stick, aerosol) against stress-induced sweating and malodor formation. We utilized the widely accepted Trier Social Stress Test (TSST) to induce psychosocial stress in female and male volunteers (18 - 40 years) and determined physiological stress parameters. To additionally assess the efficacy of the test AP roll-on against thermally-induced sweating, a hot room study was performed. Increasing heart rates and an augmentation of saliva cortisol levels during the TSST indicated a substantial stress reaction which was paralleled by a pronounced sweat production in the untreated axillae of both males and females. Forty-eight hours after application, all three test APs significantly decreased the amount of sweat in the treated axillae independent of gender. With respect to AP effects on malodor production, trained sniffers assessed sweat samples collected during the TSST from the untreated axillae as significantly more malodorous than comparable samples from the AP-treated axillae. Also, independent of gender the test AP roll-on significantly decreased the thermally-induced sweat in the AP-treated axilla. We show for the first time a highly effective reduction of emotionally-induced axillary sweating and malodor production for three different application forms 48 h after the last product use. The specially developed roll-on, stick, and aerosol AP provide long-term protection against stress-induced sweat which is of high relevance in everyday life. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Sweat-inducing physiological challenges do not result in acute changes in hair cortisol concentrations.

PubMed

Grass, Juliane; Kirschbaum, Clemens; Miller, Robert; Gao, Wei; Steudte-Schmiedgen, Susann; Stalder, Tobias

2015-03-01

Hair cortisol concentrations (HCC) are assumed to provide a stable, integrative marker of long-term systemic cortisol secretion. However, contrary to this assumption, some recent observations have raised the possibility that HCC may be subject to acute influences, potentially related to cortisol incorporation from sweat. Here, we provide a first detailed in vivo investigation of this possibility comprising two independent experimental studies: study I (N=42) used a treadmill challenge to induce sweating together with systemic cortisol reactivity while in study II (N=52) a sauna bathing challenge induced sweating without systemic cortisol changes. In both studies, repeated assessments of HCC, salivary cortisol, cortisol in sweat and individuals' sweating rate (single assessment) were conducted on the experimental day and at a next-day follow-up. Results across the two studies consistently revealed that HCC were not altered by the acute interventions. Further, HCC were found to be unrelated to acute salivary cortisol reactivity, sweat cortisol levels, sweating rate or the time of examination. In line with previous data, cortisol levels in sweat were strongly related to total salivary cortisol output across the examined periods. The present results oppose recent case report data by showing that single sweat-inducing interventions do not result in acute changes in HCC. Our data also tentatively speak against the notion that cortisol in sweat may be a dominant source of HCC. Further, our findings also indicate that HCC are not subject to diurnal variation. This research provides further support for hair cortisol analysis as a marker of integrated long-term systemic cortisol secretion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evidence for metaboreceptor stimulation of sweating in normothermic and heat-stressed humans

NASA Technical Reports Server (NTRS)

Shibasaki, M.; Kondo, N.; Crandall, C. G.

2001-01-01

1. Isometric handgrip (IHG) exercise increases sweat rate and arterial blood pressure, and both remain elevated during post-exercise ischaemia. The purpose of this study was to identify whether the elevation in arterial blood pressure during post-exercise ischaemia contributes to the increase in sweating. 2. In normothermia and during whole-body heating, 2 min IHG exercise at 40% maximal voluntary contraction, followed by 2 min post-exercise ischaemia, was performed with and without bolus intravenous administration of sodium nitroprusside during the ischaemic period. Sodium nitroprusside was administered to reduce blood pressure during post-exercise ischaemia to pre-exercise levels. Sweat rate was monitored over two microdialysis membranes placed in the dermal space of forearm skin. One membrane was perfused with the acetylcholinesterase inhibitor neostigmine, while the other was perfused with the vehicle. 3. In normothermia, IHG exercise increased sweat rate at the neostigmine-treated site but not at the control site. Sweat rate remained elevated during post-exercise ischaemia even after mean arterial blood pressure returned to the pre-IHG exercise baseline. Subsequent removal of the ischaemia stimulus returned sweat rate to pre-IHG exercise levels. Sweat rate during post-exercise ischaemia without sodium nitroprusside administration followed a similar pattern. 4. During whole-body heating, IHG exercise increased sweat rate at both neostigmine-treated and untreated sites. Similarly, regardless of whether mean arterial blood pressure remained elevated or was reduced during post-exercise ischaemia, sweat rate remained elevated during the ischaemic period. 5. These results suggest that sweating in non-glabrous skin during post-IHG exercise ischaemia is activated by metaboreflex stimulation and not via baroreceptor loading.

Assessment of Correlation between Sweat Chloride Levels and Clinical Features of Cystic Fibrosis Patients.

PubMed

Raina, Manzoor A; Khan, Mosin S; Malik, Showkat A; Raina, Ab Hameed; Makhdoomi, Mudassir J; Bhat, Javed I; Mudassar, Syed

2016-12-01

Cystic Fibrosis (CF) is an autosomal recessive disorder and the incidence of this disease is undermined in Northern India. The distinguishable salty character of the sweat belonging to individuals suffering from CF makes sweat chloride estimation essential for diagnosis of CF disease. The aim of this prospective study was to elucidate the relationship of sweat chloride levels with clinical features and pattern of CF. A total of 182 patients, with clinical features of CF were included in this study for quantitative measurement of sweat chloride. Sweat stimulation and collection involved pilocarpine iontophoresis based on the Gibson and Cooks methodology. The quantitative estimation of chloride was done by Schales and Schales method with some modifications. Cystic Fibrosis Trans Membrane Conductance Regulator (CFTR) mutation status was recorded in case of patients with borderline sweat chloride levels to correlate the results and for follow-up. Out of 182 patients having clinical features consistent with CF, borderline and elevated sweat chloride levels were present in 9 (5%) and 41 (22.5%) subjects respectively. Elevated sweat chloride levels were significantly associated with wheeze, Failure To Thrive (FTT), history of CF in Siblings, product of Consanguineous Marriage (CM), digital clubbing and steatorrhoea on univariate analysis. On multivariate analysis only wheeze, FTT and steatorrhoea were found to be significantly associated with elevated sweat chloride levels (p<0.05). Among the nine borderline cases six cases were positive for at least two CFTR mutations and rest of the three cases were not having any mutation in CFTR gene. The diagnosis is often delayed and the disease is advanced in most patients at the time of diagnosis. Sweat testing is a gold standard for diagnosis of CF patients as genetic mutation profile being heterozygous and unlikely to become diagnostic test.

In Vivo Readout of CFTR Function: Ratiometric Measurement of CFTR-Dependent Secretion by Individual, Identifiable Human Sweat Glands

PubMed Central

Wine, Jeffrey J.; Char, Jessica E.; Chen, Jonathan; Cho, Hyung-ju; Dunn, Colleen; Frisbee, Eric; Joo, Nam Soo; Milla, Carlos; Modlin, Sara E.; Park, Il-Ho; Thomas, Ewart A. C.; Tran, Kim V.; Verma, Rohan; Wolfe, Marlene H.

2013-01-01

To assess CFTR function in vivo, we developed a bioassay that monitors and compares CFTR-dependent and CFTR-independent sweat secretion in parallel for multiple (∼50) individual, identified glands in each subject. Sweating was stimulated by intradermally injected agonists and quantified by optically measuring spherical sweat bubbles in an oil-layer that contained dispersed, water soluble dye particles that partitioned into the sweat bubbles, making them highly visible. CFTR-independent secretion (M-sweat) was stimulated with methacholine, which binds to muscarinic receptors and elevates cytosolic calcium. CFTR-dependent secretion (C-sweat) was stimulated with a β-adrenergic cocktail that elevates cytosolic cAMP while blocking muscarinic receptors. A C-sweat/M-sweat ratio was determined on a gland-by-gland basis to compensate for differences unrelated to CFTR function, such as gland size. The average ratio provides an approximately linear readout of CFTR function: the heterozygote ratio is ∼0.5 the control ratio and for CF subjects the ratio is zero. During assay development, we measured C/M ratios in 6 healthy controls, 4 CF heterozygotes, 18 CF subjects and 4 subjects with ‘CFTR-related’ conditions. The assay discriminated all groups clearly. It also revealed consistent differences in the C/M ratio among subjects within groups. We hypothesize that these differences reflect, at least in part, levels of CFTR expression, which are known to vary widely. When C-sweat rates become very low the C/M ratio also tended to decrease; we hypothesize that this nonlinearity reflects ductal fluid absorption. We also discovered that M-sweating potentiates the subsequent C-sweat response. We then used potentiation as a surrogate for drugs that can increase CFTR-dependent secretion. This bioassay provides an additional method for assessing CFTR function in vivo, and is well suited for within-subject tests of systemic, CFTR-directed therapeutics. PMID:24204751

Prolonged and localized sweat stimulation by iontophoretic delivery of the slowly-metabolized cholinergic agent carbachol.

PubMed

Simmers, Phillip; Li, S Kevin; Kasting, Gerald; Heikenfeld, Jason

2018-01-01

Continuous non-invasive sampling and sensing of multiple classes of analytes could revolutionize medical diagnostics and wearable technologies, but also remains highly elusive because of the many confounding factors for candidate biofluids such as interstitial fluid, tears, saliva, and sweat. Eccrine sweat biosensing has seen a recent surge in demonstrations of wearable sampling and sensing devices. However, for subjects at rest, access to eccrine sweat is highly limited and unpredictable compared to saliva and tears. Reported here is a prolonged and localized sweat stimulation by iontophoretic delivery of the slowly-metabolized nicotinic cholinergic agonist carbachol. Presented here are detailed measurements of natural baseline sweat rates across multiple days, confirming a clear need for localized sweat stimulation. Iontophoresis was performed with either carbachol or pilocarpine in order to stimulate sweat in subjects at rest. Furthermore, improved methods of quantifying sweat generation rates (nL/min/gland) are demonstrated. In-vivo testing reveals that carbachol stimulation can surpass a major goal of 24-h sweat access, in some cases providing more than an order of magnitude longer duration than stimulation with commonly-used pilocarpine. Also demonstrated is reduction of the traditional iontophoretic dosage for sweat stimulation (<5.25-42mC/cm 2 ). This increases the viability of repeated dosing as demonstrated herein, and for carbachol is as much as 100-1000X less than used for other applications. This work is not only significant for wearable sweat biosensing technology, but could also have broader impact for those studying topical skin products, antiperspirants, textiles and medical adhesives, nerve disorders, the effects of perspiration on skin-health, skin related diseases such as idiopathic pure sudomotor failure and hyperhidrosis, and other skin- and perspiration-related applications. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

3D bioprinting matrices with controlled pore structure and release function guide in vitro self-organization of sweat gland.

PubMed

Liu, Nanbo; Huang, Sha; Yao, Bin; Xie, Jiangfan; Wu, Xu; Fu, Xiaobing

2016-10-03

3D bioprinting matrices are novel platforms for tissue regeneration. Tissue self-organization is a critical process during regeneration that implies the features of organogenesis. However, it is not clear from the current evidences whether 3D printed construct plays a role in guiding tissue self-organization in vitro. Based on our previous study, we bioprinted a 3D matrix as the restrictive niche for direct sweat gland differentiation of epidermal progenitors by different pore structure (300-μm or 400-μm nozzle diameters printed) and reported a long-term gradual transition of differentiated cells into glandular morphogenesis occurs within the 3D construct in vitro. At the initial 14-day culture, an accelerated cell differentiation was achieved with inductive cues released along with gelatin reduction. After protein release completed, the 3D construct guide the self-organized formation of sweat gland tissues, which is similar to that of the natural developmental process. However, glandular morphogenesis was only observed in 300-μm-printed constructs. In the absence of 3D architectural support, glandular morphogenesis was not occurred. This striking finding made us to identify a previously unknown role of the 3D-printed structure in glandular tissue regeneration, and this self-organizing strategy can be applied to forming other tissues in vitro.

Age-Related Changes in Children's Hedonic Response to Male Body Odor.

ERIC Educational Resources Information Center

Stevenson, Richard J.; Repacholi, Betty M.

2003-01-01

Examined children's and adolescents' ability to identify male sweat and other odors and their rating of odors for liking. Found that only female adolescents could identify and disliked male sweat. When cued about odor identity, both male and female adolescents disliked male sweat more than children. Concluded that dislike for male sweat odor may…

Precise measurement of volume of eccrine sweat gland in mental sweating by optical coherence tomography

NASA Astrophysics Data System (ADS)

Sugawa, Yoshihiko; Fukuda, Akihiro; Ohmi, Masato

2015-04-01

We have demonstrated dynamic analysis of the physiological function of eccrine sweat glands underneath skin surface by optical coherence tomography (OCT). In this paper, we propose a method for extraction of the specific eccrine sweat gland by means of the connected component extraction process and the adaptive threshold method, where the en face OCT images are constructed by the swept-source OCT. In the experiment, we demonstrate precise measurement of the volume of the sweat gland in response to the external stimulus.

The Relevance of Cultural Activities in Ethnic Identity Among California Native American Youth

PubMed Central

Schweigman, Kurt; Soto, Claradina; Wright, Serena; Unger, Jennifer

2013-01-01

This study analyzed data from a large statewide sample of Native American adolescents throughout California to determine whether participation in cultural practices was associated with stronger ethnic identity. The Multigroup Ethnic Identity Measure (MEIM) scale was used to measure the ethnic identity of 945 Native American adolescents (416 male, 529 female) aged 13 – 19 across California. Respondents who participated in cultural activities including pow-wows, sweat lodge, drum group and roundhouse dance reported significantly higher Native American ethnic identity than their counterparts who did not take part in cultural activities. The association between cultural activities and ethnic identity was only significant among urban youth and not among reservation youth. Higher grades in school were associated with ethnic identity among females but not among males. Findings from this study show a strong association between cultural activities and traditional practices with tribal enculturation among Native American youth in California. Cultural-based practices to enhance Native identity could be useful to improve mental and behavioral health among Native American youth. PMID:22400467

Brain stem representation of thermal and psychogenic sweating in humans.

PubMed

Farrell, Michael J; Trevaks, David; Taylor, Nigel A S; McAllen, Robin M

2013-05-15

Functional MRI was used to identify regions in the human brain stem activated during thermal and psychogenic sweating. Two groups of healthy participants aged 34.4 ± 10.2 and 35.3 ± 11.8 years (both groups comprising 1 woman and 10 men) were either heated by a water-perfused tube suit or subjected to a Stroop test, while they lay supine with their head in a 3-T MRI scanner. Sweating events were recorded as electrodermal responses (increases in AC conductance) from the palmar surfaces of fingers. Each experimental session consisted of two 7.9-min runs, during which a mean of 7.3 ± 2.1 and 10.2 ± 2.5 irregular sweating events occurred during psychogenic (Stroop test) and thermal sweating, respectively. The electrodermal waveform was used as the regressor in each subject and run to identify brain stem clusters with significantly correlated blood oxygen level-dependent signals in the group mean data. Clusters of significant activation were found with both psychogenic and thermal sweating, but a voxelwise comparison revealed no brain stem cluster whose signal differed significantly between the two conditions. Bilaterally symmetric regions that were activated by both psychogenic and thermal sweating were identified in the rostral lateral midbrain and in the rostral lateral medulla. The latter site, between the facial nuclei and pyramidal tracts, corresponds to a neuron group found to drive sweating in animals. These studies have identified the brain stem regions that are activated with sweating in humans and indicate that common descending pathways may mediate both thermal and psychogenic sweating.

The sweating foot: local differences in sweat secretion during exercise-induced hyperthermia.

PubMed

Taylor, Nigel A S; Caldwell, Joanne N; Mekjavic, Igor B

2006-10-01

Little is known regarding local differences in foot sweat secretion. Since such information is important to our understanding of sweat gland control for thermoregulatory modeling and for the design of footwear we explored this topic. Local sweat rates were investigated across core temperatures from 37-39 degrees C, achieved using endogenous (cycling) and exogenous heat (water-perfusion garment: 46 degrees C). Six healthy adults (three men, three women) performed one-legged, incremental cycling in a heated, climate-controlled chamber (36 degrees C, 60% relative humidity). Sweat rates were measured at the forehead and stationary (left) foot (capsules 3.16 cm2): three dorsal sites (base of toes, second metatarsal, and mid point), the lateral, and the central plantar surfaces. Terminal core temperatures ranged between 38.3-39.1 oC, with peak heart rates of 155-187 bpm. Most foot sweat rates were < 50% of that observed at the forehead: dorsal 1 (38%); dorsal 2 (54%); dorsal 3 (37%); lateral (24%); and plantar surfaces (18%). When averaged across the trial, local sweat rates were: 2.61 (forehead); 0.98 (dorsal 1); 1.39 (dorsal 2); 0.95 (dorsal 3); 0.62 (lateral); and 0.47 mg cm2 2 min-1 (plantar). Two key observations emerged. First, sweat secretion from the experimental foot averaged 30 ml x h(-1), peaking in the last 5 min at 50 ml x h(-1). Second, approximately 70% of the measured sweat flow emanated from the upper skin surfaces, with only 30% coming from the plantar surface.

Matrigel basement membrane matrix induces eccrine sweat gland cells to reconstitute sweat gland-like structures in nude mice.

PubMed

Li, Haihong; Chen, Lu; Zeng, Shaopeng; Li, Xuexue; Zhang, Xiang; Lin, Changmin; Zhang, Mingjun; Xie, Sitian; He, Yunpu; Shu, Shenyou; Yang, Lvjun; Tang, Shijie; Fu, Xiaobing

2015-03-01

Severe burn results in irreversible damage to eccrine sweat glands, for which no effective treatment is available. Interaction between the extracellular matrix and epithelial cells is critical for proper three-dimensional organization and function of the epithelium. Matrigel-embedded eccrine sweat gland cells were subcutaneously implanted into the inguinal regions of nude mice. Two weeks later, the Matrigel plugs were removed and evaluated for series of detection items. Sweat gland cells developed into sweat gland-like structures in the Matrigel plugs based on: (1) de novo formation of tubular-like structures with one or more hollow lumens, (2) expression of epithelial and sweat gland markers (pancytokeratin, CK5/7/14/19, α-SMA and CEA), (3) basement membrane formation, (4) myoepithelial cells presenting in and encompassing the tubular-like structures, (5) cellular polarization, evident by the expression of tight junction proteins (claudin-1 and ZO-2), anchoring junctions (desmoglein-1 and -2 and E-cadherin) and CEA in the luminal membrane, (6) expression of proteins related to sweat secretion and absorption (Na(+)-K(+)-ATPase α/β, Na(+)-K(+)-2Cl-cotranspoter 1, Na(+)/H(+) exchanger 1, aquaporin-5, epithelial sodium channel, cystic fibrosis transmembrane conductance regulator, potassium channel and vacuolar-type H+-ATPase), and (7) about 20% of the tubular-like structures are de novo coils and 80% are de novo ducts. This study provides not only an excellent model to study eccrine sweat gland development, cytodifferentiation and reconstitution, but also an in vivo model for regeneration of eccrine sweat glands. Copyright © 2015 Elsevier Inc. All rights reserved.

Autonomous sweat extraction and analysis applied to cystic fibrosis and glucose monitoring using a fully integrated wearable platform.

PubMed

Emaminejad, Sam; Gao, Wei; Wu, Eric; Davies, Zoe A; Yin Yin Nyein, Hnin; Challa, Samyuktha; Ryan, Sean P; Fahad, Hossain M; Chen, Kevin; Shahpar, Ziba; Talebi, Salmonn; Milla, Carlos; Javey, Ali; Davis, Ronald W

2017-05-02

Perspiration-based wearable biosensors facilitate continuous monitoring of individuals' health states with real-time and molecular-level insight. The inherent inaccessibility of sweat in sedentary individuals in large volume (≥10 µL) for on-demand and in situ analysis has limited our ability to capitalize on this noninvasive and rich source of information. A wearable and miniaturized iontophoresis interface is an excellent solution to overcome this barrier. The iontophoresis process involves delivery of stimulating agonists to the sweat glands with the aid of an electrical current. The challenge remains in devising an iontophoresis interface that can extract sufficient amount of sweat for robust sensing, without electrode corrosion and burning/causing discomfort in subjects. Here, we overcame this challenge through realizing an electrochemically enhanced iontophoresis interface, integrated in a wearable sweat analysis platform. This interface can be programmed to induce sweat with various secretion profiles for real-time analysis, a capability which can be exploited to advance our knowledge of the sweat gland physiology and the secretion process. To demonstrate the clinical value of our platform, human subject studies were performed in the context of the cystic fibrosis diagnosis and preliminary investigation of the blood/sweat glucose correlation. With our platform, we detected the elevated sweat electrolyte content of cystic fibrosis patients compared with that of healthy control subjects. Furthermore, our results indicate that oral glucose consumption in the fasting state is followed by increased glucose levels in both sweat and blood. Our solution opens the possibility for a broad range of noninvasive diagnostic and general population health monitoring applications.

Cutaneous microdialysis as a novel means of continuously stimulating eccrine sweat glands in vivo.

PubMed

Morgan, Caroline J; Friedmann, Peter S; Church, Martin K; Clough, Geraldine F

2006-06-01

Previous studies of the pharmacological regulation of sweat gland function in humans have administered agonists or antagonists systemically, by local intradermal injection or by iontophoresis. This has not allowed prolonged or steady-state activation of sweat glands to be examined. In this study, we used the technique of dermal microdialysis to administer pharmacological agents singly and in combination for up to 5 hours. Muscarinic stimulation with pilocarpine nitrate (50 mug ml(-1) to 1.66 mg ml(-1)) produced a sigmoid dose response curve, with maximal sweating (measured as transepidermal water loss) (mean 70 g m(-2) hour(-1)) after 15 minutes. This was sustained at steady-state levels (55 g m(-2) hour(-1)) until perfusion stopped. Perfusion with atropine (0.003 mg ml(-1)) reduced sweating below baseline and blocked pilocarpine-induced sweating completely. Noradrenaline (0.005 mg ml(-1)) induced much lower sweat rates than pilocarpine (56.8+/-1.62 g m(-2) hour(-1) vs 8.2+/-1.2 g m(-2) hour(-1), respectively, P<0.001) and this was unaffected by co-administration of atropine. This method has made it possible to show that sweat glands are capable of sustaining near maximal activity for at least 5 hours. The method has future application in investigation of conditions with disordered sweat gland activity.

Proteomic profiling of eccrine sweat reveals its potential as a diagnostic biofluid for active tuberculosis.

PubMed

Adewole, Olanisun Olufemi; Erhabor, Greg Efosa; Adewole, Temitayo Oluwatoyin; Ojo, Abiodun Oluwasesan; Oshokoya, Harriet; Wolfe, Lisa M; Prenni, Jessica E

2016-05-01

Excessive sweating is a common symptom of the disease and an unexplored biofluid for TB diagnosis; we conducted a proof-of-concept study to identify potential diagnostic biomarkers of active TB in eccrine sweat. We performed a global proteomic profile of eccrine sweat sampled from patients with active pulmonary TB, other lung diseases (non-TB disease), and healthy controls. A comparison of proteomics between Active-TB, Non-TB, and Healthy Controls was done in search for potential biomarkers of active TB. Sweat specimens were pooled from 32 active TB patients, 27 patients with non-TB diseases, and 24 apparently healthy controls, all were negative for HIV. Over 100 unique proteins were identified in the eccrine sweat of all three groups. Twenty-six proteins were exclusively detected in the sweat of patients with active TB while the remaining detected proteins overlapped between three groups. Gene ontology evaluation indicated that the proteins detected uniquely in sweat of active TB patients were involved in immune response and auxiliary protein transport. Gene products for cellular components (e.g. ribosomes) were detected only in active TB patients. Data are available via ProteomeXchange with identifier PXD003224. Proteomics of sweat from active TB patients is a viable approach for biomarker identification, which could be used to develop a nonsputum-based test for detection of active TB. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of a method for enhancing metabolomics coverage of human sweat by gas chromatography-mass spectrometry in high resolution mode.

PubMed

Delgado-Povedano, M M; Calderón-Santiago, M; Priego-Capote, F; Luque de Castro, M D

2016-01-28

Sweat has recently gained popularity as clinical sample in metabolomics analysis as it is a non-invasive biofluid the composition of which could be modified by certain pathologies, as is the case with cystic fibrosis that increases chloride levels in sweat. However, the whole composition of sweat is still unknown and there is a lack of analytical strategies for sweat analysis. The aim of the present study was to develop and validate a method for metabolomic analysis of human sweat by gas chromatography-time of flight/mass spectrometry (GC-TOF/MS) in high resolution mode. Thus, different sample preparation strategies were compared to check their effect on the profile of sweat metabolites. Sixty-six compounds were tentatively identified by the obtained MS information. Amino acids, dicarboxylic acids and other interesting metabolites such as myo-inositol and urocanic acid were identified. Among the tested protocols, methyoxiamination plus silylation after deproteinization was the most suited option to obtain a representative snapshot of sweat metabolome. The intra-day repeatability of the method ranged from 0.60 to 16.99% and the inter-day repeatability from 2.75 to 31.25%. As most of the identified metabolites are involved in key biochemical pathways, this study opens new possibilities to the use of sweat as a source of metabolite biomarkers of specific disorders. Copyright © 2015 Elsevier B.V. All rights reserved.

Flexible nanoporous tunable electrical double layer biosensors for sweat diagnostics.

PubMed

Munje, Rujuta D; Muthukumar, Sriram; Panneer Selvam, Anjan; Prasad, Shalini

2015-09-30

An ultra-sensitive and highly specific electrical double layer (EDL) modulated biosensor, using nanoporous flexible substrates for wearable diagnostics is demonstrated with the detection of the stress biomarker cortisol in synthetic and human sweat. Zinc oxide thin film was used as active region in contact with the liquid i.e. synthetic and human sweat containing the biomolecules. Cortisol detection in sweat was accomplished by measuring and quantifying impedance changes due to modulation of the double layer capacitance within the electrical double layer through the application of a low orthogonally directed alternating current (AC) electric field. The EDL formed at the liquid-semiconductor interface was amplified in the presence of the nanoporous flexible substrate allowing for measuring the changes in the alternating current impedance signal due to the antibody-hormone interactions at diagnostically relevant concentrations. High sensitivity of detection of 1 pg/mL or 2.75 pmol cortisol in synthetic sweat and 1 ng/mL in human sweat is demonstrated with these novel biosensors. Specificity in synthetic sweat was demonstrated using a cytokine IL-1β. Cortisol detection in human sweat was demonstrated over a concentration range from 10-200 ng/mL.

Flexible nanoporous tunable electrical double layer biosensors for sweat diagnostics

NASA Astrophysics Data System (ADS)

Munje, Rujuta D.; Muthukumar, Sriram; Panneer Selvam, Anjan; Prasad, Shalini

2015-09-01

An ultra-sensitive and highly specific electrical double layer (EDL) modulated biosensor, using nanoporous flexible substrates for wearable diagnostics is demonstrated with the detection of the stress biomarker cortisol in synthetic and human sweat. Zinc oxide thin film was used as active region in contact with the liquid i.e. synthetic and human sweat containing the biomolecules. Cortisol detection in sweat was accomplished by measuring and quantifying impedance changes due to modulation of the double layer capacitance within the electrical double layer through the application of a low orthogonally directed alternating current (AC) electric field. The EDL formed at the liquid-semiconductor interface was amplified in the presence of the nanoporous flexible substrate allowing for measuring the changes in the alternating current impedance signal due to the antibody-hormone interactions at diagnostically relevant concentrations. High sensitivity of detection of 1 pg/mL or 2.75 pmol cortisol in synthetic sweat and 1 ng/mL in human sweat is demonstrated with these novel biosensors. Specificity in synthetic sweat was demonstrated using a cytokine IL-1β. Cortisol detection in human sweat was demonstrated over a concentration range from 10-200 ng/mL.

Pulsed direct and constant direct currents in the pilocarpine iontophoresis sweat chloride test.

PubMed

Gomez, Carla Cristina Souza; Servidoni, Maria de Fatima; Marson, Fernando Augusto de Lima; Canavezi, Paulo Jose Coelho; Vinagre, Adriana Mendes; Costa, Eduardo Tavares; Ribeiro, Antonio Fernando; Ribeiro, Maria Angela Gonçalves de Oliveira; Toro, Adyleia Aparecida Dalbo Contrera; Pavan, Celia Regina; Rondon, Michelle Vivine Sá Dos Santos; Lorena, Sonia Leticia Silva; Vieria, Francisco Ubaldi; Ribeiro, Jose Dirceu

2014-12-13

The classic sweat test (CST) is the golden standard for cystic fibrosis (CF) diagnosis. Then, our aim was compare the production and volume of sweat, and side effects caused by pulsed direct current (PDC) and constant direct current (CDC). To determine the optimal stimulation time (ST) for the sweat collection. To verify the PDC as CF diagnosis option. Prospective study with cross-sectional experimental intervention. Experiment 1 (right arm): PDC and CDC. ST at 10 min and sweat collected at 30 min. Currents of 0.5; 0.75; 1.0 and 1.5 mA and frequencies of 0, 200, 1,000 and 5,000 Hz applied. Experiment 2 (left arm): current of 1.0 mA, ST at 5 and 10 min and sweat collected at 15 and 30 min with frequencies of 0; 200; 1,000 and 5,000 Hz applied Experiments 1 and 2 were performed with current density (CD) from 0.07 to 0.21 mA/cm2. Experiment 3: PDC was used in typical CF patients with two CFTR mutations screened and or with CF diagnosis by rectal biopsy and patients with atypical CF. 48 subjects (79.16% female) with average of 29.54 ± 8.87 years old were enrolled. There was no statistical difference between the interaction of frequency and current in the sweat weight (p = 0.7488). Individually, positive association was achieved between weight sweat and stimulation frequency (p = 0.0088); and current (p = 0.0025). The sweat production was higher for 10 min of stimulation (p = 0.0023). The sweat collection was better for 30 min (p = 0.0019). The skin impedance was not influenced by ST and sweat collection (p > 0.05). The current frequency was inversely associated with the skin impedance (p < 0.0001). The skin temperature measured before stimulation was higher than after (p < 0.0001). In Experiment 3 (29 subjects) the PDC showed better kappa index compared to CDC (0.9218 versus 0.5205, respectively). The performance of the CST with CDC and PDC with CD of 0.14 to 0.21 mA/cm2 showed efficacy in steps of stimulation and collection of sweat, without side effects. The optimal stimulation time and sweat collection were, respectively, 10 and 30 min.

Attitudes about Advances in Sweat Patch Testing in Drug Courts: Insights from a Case Study in Southern California

ERIC Educational Resources Information Center

Polzer, Katherine

2010-01-01

Drug courts are reinventing the drug testing framework by experimenting with new methods, including use of the sweat patch. The sweat patch is a band-aid like strip used to monitor drug court participants. The validity and reliability of the sweat patch as an effective testing method was examined, as well as the effectiveness, meaning how likely…

Prevalence and predictors of night sweats, day sweats, and hot flashes in older primary care patients: an OKPRN study.

PubMed

Mold, James W; Roberts, Michelle; Aboshady, Hesham M

2004-01-01

We wanted to estimate the prevalence of night sweats, day sweats, and hot flashes in older primary care patients and identify associated factors. We undertook a cross-sectional study of patients older than 64 years recruited from the practices of 23 family physicians. Variables included sociodemographic information, health habits, chronic medical problems, symptoms, quality of life, and the degree to which patients were bothered by night sweats, daytime sweating, and hot flashes. Among the 795 patients, 10% reported being bothered by night sweats, 9% by day sweats, and 8% by hot flashes. Eighteen percent reported at least 1 of these symptoms. The 3 symptoms were strongly correlated. Factors associated with night sweats in the multivariate models were age (odds ratio [OR] 0.94/y; 95% confidence interval [CI], 0.89-0.98), fever (OR 12.60; 95% CI, 6.58-24.14), muscle cramps (OR 2.84; 95% CI, 1.53-5.24), numbness of hands and feet (OR 3.34; 95% CI, 1.92-5.81), impaired vision (OR 2.45; 95% CI, 1.41-4.27), and hearing loss (OR 1.84; 95% CI, 1.03-3.27). Day sweats were associated with fever (OR 4.10; 95% CI, 2.14-7.87), restless legs (OR 3.22; 95% CI, 1.76-5.89), lightheadedness (OR 2.24; 95% CI, 1.30-3.88), and diabetes (OR 2.19; 95% CI, 1.22-3.92). Hot flashes were associated with nonwhite race (OR 3.10; 95% CI, 1.60-5.98), fever (OR 3.98; 95% CI, 1.97-8.04), bone pain (OR 2.31; CI 95%: 1.30-4.08), impaired vision (OR 2.12; 95% CI, 1.19-3.79), and nervous spells (OR 1.87; 95% CI, 1.01-3.46). All 3 symptoms were associated with reduced quality of life. Many older patients are bothered by night sweats, day sweats, and hot flashes. Though these symptoms are similar and related, they have somewhat different associations with other variables. Clinical evaluation should include questions about febrile illnesses, sensory deficits, anxiety, depression, pain, muscle cramps, and restless legs syndrome.

Observation of the sweating in lipstick by scanning electron microscopy.

PubMed

Seo, S Y; Lee, I S; Shin, H Y; Choi, K Y; Kang, S H; Ahn, H J

1999-06-01

The relationship between the wax matrix in lipstick and sweating has been investigated by observing the change of size and shape of the wax matrix due to sweating by Scanning Electron Microscopy (SEM). For observation by SEM, a lipstick sample was frozen in liquid nitrogen. The oil in the lipstick was then extracted in cold isopropanol (-70 degrees C) for 1-3 days. After the isopropanol was evaporated, the sample was sputtered with gold and examined by SEM. The change of wax matrix underneath the surface from fine, uniform structure to coarse, nonuniform structure resulted from the caking of surrounding wax matrix. The oil underneath the surface migrated to the surface of lipstick with sweating; consequently the wax matrix in that region was rearranged into the coarse matrix. In case of flamed lipstick, sweating was delayed and the wax matrix was much coarser than that of the unflamed one. The larger wax matrix at the surface region was good for including oil. The effect of molding temperature on sweating was also studied. As the molding temperature rose, sweating was greatly reduced and the size of the wax matrix increased. It was found that sweating was influenced by the compatibility of wax and oil. A formula consisting of wax and oil that have good compatibility has a tendency to reduce sweating and increase the size of the wax matrix. When pigments were added to wax and oil, the size of the wax matrix was changed, but in all cases sweating was increased due to the weakening of the binding force between wax and oil. On observing the thick membrane of wax at the surface of lipstick a month after molding it was also found that sweating was influenced by ageing. In conclusion, the structure of the wax matrix at the surface region of lipstick was changed with the process of flaming, molding temperature, compatibility of wax and oil, addition of pigment, and ageing. In most cases, as the size of the wax matrix was increased, sweating was reduced and delayed.

Adding heat to the live-high train-low altitude model: a practical insight from professional football

PubMed Central

Buchheit, M; Racinais, S; Bilsborough, J; Hocking, J; Mendez-Villanueva, A; Bourdon, P C; Voss, S; Livingston, S; Christian, R; Périard, J; Cordy, J; Coutts, A J

2013-01-01

Objectives To examine with a parallel group study design the performance and physiological responses to a 14-day off-season ‘live high-train low in the heat’ training camp in elite football players. Methods Seventeen professional Australian Rules Football players participated in outdoor football-specific skills (32±1°C, 11.5 h) and indoor strength (23±1°C, 9.3 h) sessions and slept (12 nights) and cycled indoors (4.3 h) in either normal air (NORM, n=8) or normobaric hypoxia (14±1 h/day, FiO2 15.2–14.3%, corresponding to a simulated altitude of 2500–3000 m, hypoxic (HYP), n=9). They completed the Yo-Yo Intermittent Recovery level 2 (Yo-YoIR2) in temperate conditions (23±1°C, normal air) precamp (Pre) and postcamp (Post). Plasma volume (PV) and haemoglobin mass (Hbmass) were measured at similar times and 4 weeks postcamp (4WPost). Sweat sodium concentration ((Na+)sweat) was measured Pre and Post during a heat-response test (44°C). Results Both groups showed very large improvements in Yo-YoIR2 at Post (+44%; 90% CL 38, 50), with no between-group differences in the changes (−1%; −9, 9). Postcamp, large changes in PV (+5.6%; −1.8, 5.6) and (Na+)sweat (−29%; −37, −19) were observed in both groups, while Hbmass only moderately increased in HYP (+2.6%; 0.5, 4.5). At 4WPost, there was a likely slightly greater increase in Hbmass (+4.6%; 0.0, 9.3) and PV (+6%; −5, 18, unclear) in HYP than in NORM. Conclusions The combination of heat and hypoxic exposure during sleep/training might offer a promising ‘conditioning cocktail’ in team sports. PMID:24282209

iNOS-dependent sweating and eNOS-dependent cutaneous vasodilation are evident in younger adults, but are diminished in older adults exercising in the heat

PubMed Central

Fujii, Naoto; Meade, Robert D.; Alexander, Lacy M.; Akbari, Pegah; Foudil-bey, Imane; Louie, Jeffrey C.; Boulay, Pierre

2015-01-01

Nitric oxide synthase (NOS) contributes to sweating and cutaneous vasodilation during exercise in younger adults. We hypothesized that endothelial NOS (eNOS) and neuronal NOS (nNOS) mediate NOS-dependent sweating, whereas eNOS induces NOS-dependent cutaneous vasodilation in younger adults exercising in the heat. Further, aging may upregulate inducible NOS (iNOS), which may attenuate sweating and cutaneous vasodilator responses. We hypothesized that iNOS inhibition would augment sweating and cutaneous vasodilation in exercising older adults. Physically active younger (n = 12, 23 ± 4 yr) and older (n = 12, 60 ± 6 yr) adults performed two 30-min bouts of cycling at a fixed rate of metabolic heat production (400 W) in the heat (35°C). Sweat rate and cutaneous vascular conductance (CVC) were evaluated at four intradermal microdialysis sites with: 1) lactated Ringer (control), 2) nNOS inhibitor (nNOS-I, NPLA), 3) iNOS inhibitor (iNOS-I, 1400W), or 4) eNOS inhibitor (eNOS-I, LNAA). In younger adults during both exercise bouts, all inhibitors decreased sweating relative to control, albeit a lower sweat rate was observed at iNOS-I compared with eNOS-I and nNOS-I sites (all P < 0.05). CVC at the eNOS-I site was lower than control in younger adults throughout the intermittent exercise protocol (all P < 0.05). In older adults, there were no differences between control and iNOS-I sites for sweating and CVC during both exercise bouts (all P > 0.05). We show that iNOS and eNOS are the main contributors to NOS-dependent sweating and cutaneous vasodilation, respectively, in physically active younger adults exercising in the heat, and that iNOS inhibition does not alter sweating or cutaneous vasodilation in exercising physically active older adults. PMID:26586908

iNOS-dependent sweating and eNOS-dependent cutaneous vasodilation are evident in younger adults, but are diminished in older adults exercising in the heat.

PubMed

Fujii, Naoto; Meade, Robert D; Alexander, Lacy M; Akbari, Pegah; Foudil-Bey, Imane; Louie, Jeffrey C; Boulay, Pierre; Kenny, Glen P

2016-02-01

Nitric oxide synthase (NOS) contributes to sweating and cutaneous vasodilation during exercise in younger adults. We hypothesized that endothelial NOS (eNOS) and neuronal NOS (nNOS) mediate NOS-dependent sweating, whereas eNOS induces NOS-dependent cutaneous vasodilation in younger adults exercising in the heat. Further, aging may upregulate inducible NOS (iNOS), which may attenuate sweating and cutaneous vasodilator responses. We hypothesized that iNOS inhibition would augment sweating and cutaneous vasodilation in exercising older adults. Physically active younger (n = 12, 23 ± 4 yr) and older (n = 12, 60 ± 6 yr) adults performed two 30-min bouts of cycling at a fixed rate of metabolic heat production (400 W) in the heat (35°C). Sweat rate and cutaneous vascular conductance (CVC) were evaluated at four intradermal microdialysis sites with: 1) lactated Ringer (control), 2) nNOS inhibitor (nNOS-I, NPLA), 3) iNOS inhibitor (iNOS-I, 1400W), or 4) eNOS inhibitor (eNOS-I, LNAA). In younger adults during both exercise bouts, all inhibitors decreased sweating relative to control, albeit a lower sweat rate was observed at iNOS-I compared with eNOS-I and nNOS-I sites (all P < 0.05). CVC at the eNOS-I site was lower than control in younger adults throughout the intermittent exercise protocol (all P < 0.05). In older adults, there were no differences between control and iNOS-I sites for sweating and CVC during both exercise bouts (all P > 0.05). We show that iNOS and eNOS are the main contributors to NOS-dependent sweating and cutaneous vasodilation, respectively, in physically active younger adults exercising in the heat, and that iNOS inhibition does not alter sweating or cutaneous vasodilation in exercising physically active older adults. Copyright © 2016 the American Physiological Society.

Sweat collection capsule

NASA Technical Reports Server (NTRS)

Delaplaine, R. W.; Greenleaf, J. E.

1979-01-01

Capsule, with filter paper insert, is used to collect sweat for rate monitoring, chromatographic analysis, or active sweat gland location within specified area. Construction of capsule allows change of inserts while device remains strapped in place.

Autonomous sweat extraction and analysis applied to cystic fibrosis and glucose monitoring using a fully integrated wearable platform

DOE PAGES

Emaminejad, Sam; Gao, Wei; Wu, Eric; ...

2017-04-17

Perspiration-based wearable biosensors facilitate continuous monitoring of individuals' health states with real-time and molecular-level insight. The inherent inaccessibility of sweat in sedentary individuals in large volume (≥10 μL) for on-demand and in situ analysis has limited our ability to capitalize on this noninvasive and rich source of information. A wearable and miniaturized iontophoresis interface is an excellent solution to overcome this barrier. The iontophoresis process involves delivery of stimulating agonists to the sweat glands with the aid of an electrical current. The challenge remains in devising an iontophoresis interface that can extract sufficient amount of sweat for robust sensing, withoutmore » electrode corrosion and burning/causing discomfort in subjects. Here, we overcame this challenge through realizing an electrochemically enhanced iontophoresis interface, integrated in a wearable sweat analysis platform. This interface can be programmed to induce sweat with various secretion profiles for real-time analysis, a capability which can be exploited to advance our knowledge of the sweat gland physiology and the secretion process. To demonstrate the clinical value of our platform, human subject studies were performed in the context of the cystic fibrosis diagnosis and preliminary investigation of the blood/sweat glucose correlation. With our platform, we detected the elevated sweat electrolyte content of cystic fibrosis patients compared with that of healthy control subjects. Furthermore, our results indicate that oral glucose consumption in the fasting state is followed by increased glucose levels in both sweat and blood. In conclusion, our solution opens the possibility for a broad range of noninvasive diagnostic and general population health monitoring applications.« less

Biological Variation of Chloride and Sodium in Sweat Obtained by Pilocarpine Iontophoresis in Adults: How Sure are You About Sweat Test Results?

PubMed

Willems, Philippe; Weekx, Steven; Meskal, Anissa; Schouwers, Sofie

2017-04-01

The measurement of chloride and sodium concentrations in sweat is an important test for the diagnosis of cystic fibrosis (CF). The aim of this study was to assess the analytical variation (CV A ) and within-subject (CV I ) and between-subject (CV G ) biological variation of chloride and sodium concentrations in sweat, collected by pilocarpine iontophoresis and to determine their effect on the clinical interpretation of sweat test results. Twelve Caucasian adults (six male and six female) without symptoms suggestive for CF and with a mean age of 41 years (range 28-59) were included in the study. At least eight samples of sweat were collected from each individual by pilocarpine iontophoresis. Chloride and sodium concentrations were measured in duplicate for each sample using ion selective electrodes. After the removal of outliers, the CV A , CV I , and CV G of chloride and sodium were determined, and their impact on measurement uncertainty and reference change value were calculated. The CV A , CV I , and CV G of chloride in sweat samples were 6.5, 17.7, and 47.2%, respectively. The CV A , CV I , and CV G of sodium sweat samples were 6.0, 17.5, and 42.6%, respectively. Our study indicates that sweat chloride and sodium concentration results must be interpreted with great care. Different components of variation, particularly the biological variations, have a considerable impact on the interpretation of these results. If no pre-analytical, analytical, or post-analytical errors are suspected, repeated sweat testing to confirm first-measurement results might not be desirable.

Transition duration of ingested deuterium oxide to eccrine sweat during exercise in the heat.

PubMed

Church, Adam; Lee, Fanny; Buono, Michael J

2017-01-01

The time necessary for the initial appearance of ingested water as sweat during exercise in the heat remains unknown. Based on the current literature, we estimated fluid transition through the body, from ingestion to appearance as sweat, to have a minimum time duration of approximately three minutes. The purpose of this study was to test this prediction and identify the time necessary for the initial enrichment of deuterium oxide (D 2 O) in sweat following ingestion during exercise in the heat. Eight participants performed moderate intensity (40% of maximal oxygen uptake) treadmill exercise in an environmental chamber (40°C, 40% rH) to induce active sweating. After fifteen minutes, while continuing to walk, participants consumed D 2 O (0.15mlkg -1 ) in a final volume of 50ml water. Scapular sweat samples were collected one minute prior to and ten minutes post-ingestion. Samples were analyzed for sweat D 2 O concentration using isotope ratio mass spectrometry and compared to baseline. Mean±SD ∆ sweat D 2 O concentration at minutes one and two post-ingestion were not significantly higher than baseline (0min). Minutes three (9±3ppm) through ten (23±11ppm) post-ingestion had ∆ sweat D 2 O concentrations significantly (P<0.05) higher than baseline. Such results suggest that ingested water rapidly transports across the mucosal membrane of the alimentary canal into the vasculature space, enters the extravascular fluid, and is actively secreted by the eccrine sweat glands onto the surface of the skin for potential evaporation in as little as three minutes during exercise in the heat. Copyright © 2016 Elsevier Ltd. All rights reserved.

Leaching from the stratum corneum does not explain the previously reported elevated potassium ion concentration in sweat.

PubMed

Buono, Michael J; Stone, Michael; Cannon, Daniel T

2016-03-01

The purpose of this study was to determine if K+ is leached from the stratum corneum when sweat is present on the skin's surface. The results will help address whether sweat [K+] previously reported in the literature are artifactually elevated as a result of K+ leaching. Twelve (six female, six male) healthy volunteers participated in this study. After thorough skin cleansing and preparation with isopropyl alcohol and high-performance liquid chromatography-grade distilled water, three sites were chosen and a 50 μL drop of artificial sweat was pipetted directly onto the skin. The artificial sweat had a [K+] of 4 mEq·L-1, an osmolality of 120 mosm·L-1, and a pH of 6.0. Immediately following, a clear plastic cover slip (~6 cm2) with a shallow 0.8 cm2 convex impression in the center was applied over each drop, preventing evaporation. Each sample was allowed to sit on the forearm, under the plastic cover slip, for 10 min. The mean (±SD) [K+] in 'artificial' sweat not exposed to the skin was measured to be 4.2±0.4 mEq·L-1. After 10 min of exposure to the stratum corneum of the forearm, the artificial sweat had a mean (±SD) [K+] of 3.9±0.3 mEq·L-1. There was no significant difference (p>0.05) in the [K+] between the control artificial sweat and the samples collected after 10 min of exposure to forearm skin. These results do not support the hypothesis that significant K+ leaching from the stratum corneum into standing sweat is the cause for the previously reported elevated sweat [K+].

A Preliminary Study of Biomonitoring for Bisphenol-A in Human Sweat.

PubMed

Porucznik, Christina A; Cox, Kyley J; Wilkins, Diana G; Anderson, David J; Bailey, Nicole M; Szczotka, Kathryn M; Stanford, Joseph B

2015-09-01

Measurement of human exposure to the endocrine disruptor bisphenol-A (BPA) is hampered by the ubiquitous but transient exposure for most individuals, coupled with a short metabolic half-life which leads to high inter- and intra-individual variability. We investigated the possibility of measuring multiday exposure to BPA in human sweat among volunteer participants with the goal of identifying an exposure assessment method less affected by temporal variability. We recruited 50 participants to wear a sweat collection patch (PharmChek(®)) for 7 days with concurrent collection of daily first-morning urine. Urines and sweat patch extracts were analyzed with quantitative LC-MS-MS using a method we previously validated. In addition, a human volunteer consumed one can of commercially available soup (16 oz, 473 cm(3)) daily for 3 days and collected urine. Sweat patches (n = 2, 1 per arm) were worn for the 3 days of the study. BPA was detected in quality control specimens prepared by fortification of BPA to sweat patches, but was only detected at 5× above average background on three participant patches. Although the highest measured urine BPA concentration was 195 ng/mL for an individual with deliberate exposure, no BPA was detected above background in the corresponding sweat patches. In this preliminary investigation, the use of sweat patches primarily worn on the upper-outer arm did not detect BPA exposures that were documented by urine monitoring. The absence of BPA in sweat patches may be due to several factors, including insufficient quantity of specimen per patch, or extremely low concentrations of BPA in naturally occurring sweat, among others. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Autonomous sweat extraction and analysis applied to cystic fibrosis and glucose monitoring using a fully integrated wearable platform

PubMed Central

Emaminejad, Sam; Gao, Wei; Wu, Eric; Davies, Zoe A.; Yin Yin Nyein, Hnin; Challa, Samyuktha; Ryan, Sean P.; Fahad, Hossain M.; Chen, Kevin; Shahpar, Ziba; Talebi, Salmonn; Milla, Carlos; Javey, Ali; Davis, Ronald W.

2017-01-01

Perspiration-based wearable biosensors facilitate continuous monitoring of individuals’ health states with real-time and molecular-level insight. The inherent inaccessibility of sweat in sedentary individuals in large volume (≥10 µL) for on-demand and in situ analysis has limited our ability to capitalize on this noninvasive and rich source of information. A wearable and miniaturized iontophoresis interface is an excellent solution to overcome this barrier. The iontophoresis process involves delivery of stimulating agonists to the sweat glands with the aid of an electrical current. The challenge remains in devising an iontophoresis interface that can extract sufficient amount of sweat for robust sensing, without electrode corrosion and burning/causing discomfort in subjects. Here, we overcame this challenge through realizing an electrochemically enhanced iontophoresis interface, integrated in a wearable sweat analysis platform. This interface can be programmed to induce sweat with various secretion profiles for real-time analysis, a capability which can be exploited to advance our knowledge of the sweat gland physiology and the secretion process. To demonstrate the clinical value of our platform, human subject studies were performed in the context of the cystic fibrosis diagnosis and preliminary investigation of the blood/sweat glucose correlation. With our platform, we detected the elevated sweat electrolyte content of cystic fibrosis patients compared with that of healthy control subjects. Furthermore, our results indicate that oral glucose consumption in the fasting state is followed by increased glucose levels in both sweat and blood. Our solution opens the possibility for a broad range of noninvasive diagnostic and general population health monitoring applications. PMID:28416667

Autonomous sweat extraction and analysis applied to cystic fibrosis and glucose monitoring using a fully integrated wearable platform

DOE Office of Scientific and Technical Information (OSTI.GOV)

Emaminejad, Sam; Gao, Wei; Wu, Eric

Perspiration-based wearable biosensors facilitate continuous monitoring of individuals' health states with real-time and molecular-level insight. The inherent inaccessibility of sweat in sedentary individuals in large volume (≥10 μL) for on-demand and in situ analysis has limited our ability to capitalize on this noninvasive and rich source of information. A wearable and miniaturized iontophoresis interface is an excellent solution to overcome this barrier. The iontophoresis process involves delivery of stimulating agonists to the sweat glands with the aid of an electrical current. The challenge remains in devising an iontophoresis interface that can extract sufficient amount of sweat for robust sensing, withoutmore » electrode corrosion and burning/causing discomfort in subjects. Here, we overcame this challenge through realizing an electrochemically enhanced iontophoresis interface, integrated in a wearable sweat analysis platform. This interface can be programmed to induce sweat with various secretion profiles for real-time analysis, a capability which can be exploited to advance our knowledge of the sweat gland physiology and the secretion process. To demonstrate the clinical value of our platform, human subject studies were performed in the context of the cystic fibrosis diagnosis and preliminary investigation of the blood/sweat glucose correlation. With our platform, we detected the elevated sweat electrolyte content of cystic fibrosis patients compared with that of healthy control subjects. Furthermore, our results indicate that oral glucose consumption in the fasting state is followed by increased glucose levels in both sweat and blood. In conclusion, our solution opens the possibility for a broad range of noninvasive diagnostic and general population health monitoring applications.« less

Gender differences in the sweat response during spinning exercise.

PubMed

Hazelhurst, Lynton T; Claassen, Nicolaas

2006-08-01

The purpose of this field study was to examine gender differences in the sweat response reported in the literature in trained men and women during indoor cycling. In the present study, 14 men and 12 women took part in a 90-minute spinning class in preparation for a 108-km road race. Delta body mass, corrected for the volume of water consumed, was used to estimate sweat loss during the exercise period. Men had a significantly higher sweat rate (1.12 L.h(-1)) compared to women (0.57 L.h(-1)), despite the fact that there were no significant gender differences in ad libitum fluid intake. Future research should focus on determining whether women may be more efficient in sweat production and evaporation and whether men may have a greater reserve capacity for increased sweating.

Low abundance of sweat duct Cl− channel CFTR in both healthy and cystic fibrosis athletes with exceptionally salty sweat during exercise

PubMed Central

Haack, Karla K. V.; Pollack, Brian P.; Millard-Stafford, Mindy; McCarty, Nael A.

2011-01-01

To understand potential mechanisms explaining interindividual variability observed in human sweat sodium concentration ([Na+]), we investigated the relationship among [Na+] of thermoregulatory sweat, plasma membrane expression of Na+ and Cl− transport proteins in biopsied human eccrine sweat ducts, and basal levels of vasopressin (AVP) and aldosterone. Lower ductal luminal membrane expression of the Cl− channel cystic fibrosis transmembrane conductance regulator (CFTR) was observed in immunofluorescent staining of sweat glands from healthy young adults identified as exceptionally “salty sweaters” (SS) (n = 6, P < 0.05) and from patients with cystic fibrosis (CF) (n = 6, P < 0.005) compared with ducts from healthy young adults with “typical” sweat [Na+] (control, n = 6). Genetic testing of healthy subjects did not reveal any heterozygotes (“carriers”) for any of the 39 most common disease-causing CFTR mutations in the United States. SS had higher baseline plasma [AVP] compared with control (P = 0.029). Immunostaining to investigate a potential relationship between higher plasma [AVP] (and sweat [Na+]) and ductal membrane aquaporin-5 revealed for all groups a relatively sparse and location-dependent ductal expression of the water channel with localization primarily to the secretory coil. Availability of CFTR for NaCl transport across the ductal membrane appears related to the significant physiological variability observed in sweat salt concentration in apparently healthy humans. At present, a heritable link between healthy salty sweaters and the most prevalent disease-causing CFTR mutations cannot be established. PMID:21228336

Biological variability of the sweat chloride in diagnostic sweat tests: A retrospective analysis.

PubMed

Vermeulen, F; Lebecque, P; De Boeck, K; Leal, T

2017-01-01

The sweat test is the current gold standard for the diagnosis of cystic fibrosis (CF). CF is unlikely when sweat chloride (Cl sw ) is lower than 30mmol/L, Cl sw >60 is suggestive of CF, with intermediate values between 30 and 60mmol/L. To correctly interpret a sweat chloride value, the biological variability of the sweat chloride has to be known. Sweat tests performed in two centers using the classic Gibson and Cooke method were retrospectively reviewed (n=5904). Within test variability of Cl sw was measured by comparing results from right and left arm collected on the same day. Between test variability was calculated from subjects with sweat tests performed on more than one occasion. Within test variability of Cl sw calculated in 1022 subjects was low with differences between -3.2 (p5) and +3.6mmol/L (p95). Results from left and right arm were classified differently in only 3 subjects. Between test variability of Cl sw in 197 subjects was larger, with differences between -18.2mmol/L (p5) and +14.1mmol/L (p95) between repeat tests. Changes in diagnostic conclusion were seen in 55/197 subjects, the most frequent being changing from indeterminate to 'CF unlikely' range (48/102). Variability of sweat chloride is substantial, with frequent changes in diagnostic conclusion, especially in the intermediate range. Copyright © 2016 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

The detection of cortisol in human sweat: implications for measurement of cortisol in hair.

PubMed

Russell, Evan; Koren, Gideon; Rieder, Michael; Van Uum, Stan H M

2014-02-01

Hair cortisol analysis has been shown to be an effective measure of chronic stress. Cortisol is assumed to incorporate into hair via serum, sebum, and sweat sources; however, the extent to which sweat contributes to hair cortisol content is unknown. Sweat and saliva samples were collected from 17 subjects after a period of intensive exercise and analyzed by salivary enzyme-linked immunosorbent assay (ELISA). Subsequently, an in vitro test on exposure of hair to hydrocortisone was conducted. Residual hair samples were immersed in a 50-ng/mL hydrocortisone solution for periods lasting 15 minutes to 24 hours, followed by a wash or no-wash condition. Hair cortisol content was determined using our modified protocol for a salivary ELISA. Postexercise control sweat cortisol concentrations ranged from 8.16 to 141.7 ng/mL and correlated significantly with the log-transformed time of day. Sweat cortisol levels significantly correlated with salivary cortisol concentrations. In vitro hair exposure to a 50-ng/mL hydrocortisone solution (mimicking sweat) for 60 minutes or more resulted in significantly increased hair cortisol concentrations. Washing with isopropanol did not affect immersion-increased hair cortisol concentrations. Human sweat contains cortisol in concentrations comparable with salivary cortisol levels. This study suggests that perfuse sweating after intense exercise may increase cortisol concentrations detected in hair. This increase likely cannot be effectively decreased with conventional washing procedures and should be considered carefully in studies using hair cortisol as a biomarker of chronic stress.

Transient Sweat Rate Calculation from Humidity Measurements Under Clothing

DTIC Science & Technology

2006-07-01

Evaporation of sweat from the skin lowers core and skin temperatures, thus better enabling proper body temperatures in the heat. However, workers ...when individual workers require water to compensate for heat stress. This study made use of a sweating manikin and data from human studies to...Transient Sweat Rate Calculation from Humidity Measurements under Clothing M. Yokota, L.G. Berglund*, J.A. Gonzalez, L.A. Blanchard U.S. Army

Function of human eccrine sweat glands during dynamic exercise and passive heat stress

NASA Technical Reports Server (NTRS)

Kondo, N.; Shibasaki, M.; Aoki, K.; Koga, S.; Inoue, Y.; Crandall, C. G.

2001-01-01

The purpose of this study was to identify the pattern of change in the density of activated sweat glands (ASG) and sweat output per gland (SGO) during dynamic constant-workload exercise and passive heat stress. Eight male subjects (22.8 +/- 0.9 yr) exercised at a constant workload (117.5 +/- 4.8 W) and were also passively heated by lower-leg immersion into hot water of 42 degrees C under an ambient temperature of 25 degrees C and relative humidity of 50%. Esophageal temperature, mean skin temperature, sweating rate (SR), and heart rate were measured continuously during both trials. The number of ASG was determined every 4 min after the onset of sweating, whereas SGO was calculated by dividing SR by ASG. During both exercise and passive heating, SR increased abruptly during the first 8 min after onset of sweating, followed by a slower increase. Similarly for both protocols, the number of ASG increased rapidly during the first 8 min after the onset of sweating and then ceased to increase further (P > 0.05). Conversely, SGO increased linearly throughout both perturbations. Our results suggest that changes in forearm sweating rate rely on both ASG and SGO during the initial period of exercise and passive heating, whereas further increases in SR are dependent on increases in SGO.

Quantitative comparison of topical aluminum salt solution efficacy for management of sweating: a randomized, controlled trial.

PubMed

Swary, Jillian H; West, Dennis P; Kakar, Rohit; Ortiz, Sara; Schaeffer, Matthew R; Veledar, Emir; Alam, Murad

2015-12-01

There is a lack of studies objectively comparing the efficacy of topical antiperspirants in reducing sweat. To objectively and quantitatively compare the efficacy of two aluminum salt solutions for the reduction of induced sweating. A subject, rater, and statistician-blinded, randomized, controlled trial. Nineteen subjects were exposed to a standardized heat challenge for 3 h. Topical agent A (20% aluminum chloride hexahydrate) was randomized to either axilla, and topical agent B (1% aluminum acetate) assigned to the contralateral side. A sauna suit induced sweating during three 30-min heat intervals: (1) with no study agents (pre); (2) with both study agents, one on each side; and (3) after the agents were washed off (post). Sweat levels were measured by securing Whatman(®) filter paper to each axilla and measuring the paper weight after each heat interval. The difference in paper weight following each heat interval between Study Agent A and Study Agent B was measured by a gravimetric scale. Topical agent A had a significantly greater effect at reducing axillary sweating than B (P = 0.0002). In a sweating simulation, 20% aluminum chloride hexahydrate quantitatively and objectively appeared to reduce sweat more effectively than 1% aluminum acetate. © 2015 Wiley Periodicals, Inc.

Immunohistochemical sweat gland profiles.

PubMed

Noël, Fanchon; Piérard, Gérald E; Delvenne, Philippe; Quatresooz, Pascale; Humbert, Philippe; Piérard-Franchimont, Claudine

2013-09-01

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. © 2013 Wiley Periodicals, Inc.

Hydration: special issues for playing football in warm and hot environments.

PubMed

Shirreffs, S M

2010-10-01

The high metabolic rates and body temperatures sustained by football players during training and matches causes sweating--particularly when in warm or hot environments. There is limited published data on the effects of this sweat loss on football performance. The limited information available, together with knowledge of the effects of sweat loss in other sports with skill components as well as endurance and sprint components, suggests that the effects of sweating will be similar as in these other activities. Therefore, the generalization that, on average, a body mass reduction equivalent to 2% should be the acceptable limit of sweat losses seems reasonable. This magnitude and more, of sweat loss is a common occurrence for some players. Sodium is the main electrolyte lost in sweat but there is large variability in sodium losses between players. However, the extent of sodium losses in some players may be such that its replacement is warranted for these players. Although football is a team sport, the great individual variability in sweat and electrolyte losses of players in the same training session or match dictates that individual monitoring to determine individual water and electrolyte requirements should be an essential part of a player's nutrition strategy. © 2010 John Wiley & Sons A/S.

Audit of sweat testing: a first report from Italian Cystic Fibrosis Centres.

PubMed

Cirilli, Natalia; Padoan, Rita; Raia, Valeria

2008-09-01

Cystic Fibrosis diagnosis is confirmed using sweat test. The aim of our study was to evaluate current techniques and methodologies in use at Italian CF Care Centres. A series of questions related to the performance of the sweat test was collected by all CF Care Centres in Italy. Answers were compared with UK and NCCLS guidelines. 39/41 Centres replied to the questionnaire. A good adherence to guidelines was registered for storing samples before analysis in 90.9%, while performing CF diagnosis by at least two sweat tests, and chloride analysis were reported respectively in 100% and 75.7% of Centres. Some inconsistencies were registered for minimum acceptable sweat quantity and time to collect sweat inadequate in respectively 42.5% and 24.2% of Centres, while performing quality control procedures and referring to an external quality assessment scheme were found inadequate in respectively 54.6% and 100%. 57.6% didn't provide any appropriate analytical ranges and only 15.1% of Centres offered proper information to patients/parents. A report form, including sweat quantity, reference ranges and interpretation, was adequate only for 9.4 up to 41.4% of CF Centres. Our study showed areas of inconsistencies in sweat testing current practices in Italy and highlights the need for evidence based national guidelines to improve practice and management strategies.

The ultrastructure of the sweat glands of the ox, sheep and goat during sweating and recovery.

PubMed Central

Jenkinson, D M; Montgomery, I; Elder, H Y

1979-01-01

The ultrastructure of the sweat glands of cattle, sheep and goats was studied before, during, and after, exposure of the animals to controlled warm environments. In cattle, sweating induced little ultrastructural change in the gland, although fluid-filled spaces appeared between the myo- and secretory epithelial layers. The mechanism appears to be one of fluid transport and exocytosis of secretory vesicles, which in this species seem to be derived from the Golgi apparatus and/or mitochondria. The glands of the sheep and goat also displayed signs of vesicle exocytosis and of fluid transport during sweating. The sweating 'fatigue' in these species was apparently due to failure of the secretory cells, some of which ruptured and were extruded into the lumen. The evidence during subsequent recovery indicates that neighbouring cells spread to make contact, encase remnants of atretic cells between them and the underlying myoepithelium, and engulf them. Sweat in these species appears to be formed (a) by secretion and (b) from cells which can no longer meet the demands of stimulation. The role in sweating of cell replacement, and of undifferentiated cells found between the myo- and secretory epithelia, is discussed. Images Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 PMID:511758

Bioanalytical devices: Technological leap for sweat sensing

NASA Astrophysics Data System (ADS)

Heikenfeld, Jason

2016-01-01

Sweat analysis is an ideal method for continuously tracking a person's physiological state, but developing devices for this is difficult. A wearable sweat monitor that measures several biomarkers is a breakthrough. See Letter p.509

Higher sweat chloride levels in patients with asthma: a case-control study.

PubMed

Awasthi, Shally; Dixit, Pratibha; Maurya, Nutan

2015-02-01

To screen asthmatic patients by sweat chloride test to identify proportion with Cystic Fibrosis (CF); (Sweat chloride level >60 mmol/L). Also, to compare sweat chloride levels between cases of bronchial asthma and age and sex matched healthy children aged 5 mo-15 y. The present case-control study was conducted in a tertiary care hospital in India. Cases of bronchial asthma, diagnosed by GINA guideline 2008, and age matched healthy controls were included. Case to control ratio was 2:1. Sweat Chloride test was done by Pilocarpine Iontophoresis method. From April 2010 through May 2012, 216 asthmatics and 112 controls were recruited. Among asthmatics, there was no case of Cystic Fibrosis. Mean sweat chloride levels in asthmatics was 22.39 ± 8.45 mmol/L (inter-quartile range - 15-28 mmol/L) and in controls 19.55 ± 7.04 mmol/L (inter-quartile range - 15-23.5 mmol/L) (p value = 0.048). No Cystic Fibrosis case was identified among asthmatics. Mean sweat chloride levels were higher in asthmatics as compared to controls.

On sweat analysis for quantitative estimation of dehydration during physical exercise.

PubMed

Ring, Matthias; Lohmueller, Clemens; Rauh, Manfred; Eskofier, Bjoern M

2015-08-01

Quantitative estimation of water loss during physical exercise is of importance because dehydration can impair both muscular strength and aerobic endurance. A physiological indicator for deficit of total body water (TBW) might be the concentration of electrolytes in sweat. It has been shown that concentrations differ after physical exercise depending on whether water loss was replaced by fluid intake or not. However, to the best of our knowledge, this fact has not been examined for its potential to quantitatively estimate TBW loss. Therefore, we conducted a study in which sweat samples were collected continuously during two hours of physical exercise without fluid intake. A statistical analysis of these sweat samples revealed significant correlations between chloride concentration in sweat and TBW loss (r = 0.41, p <; 0.01), and between sweat osmolality and TBW loss (r = 0.43, p <; 0.01). A quantitative estimation of TBW loss resulted in a mean absolute error of 0.49 l per estimation. Although the precision has to be improved for practical applications, the present results suggest that TBW loss estimation could be realizable using sweat samples.

Association of sweat chloride concentration at time of diagnosis and CFTR genotype with mortality and cystic fibrosis phenotype.

PubMed

McKone, Edward F; Velentgas, Priscilla; Swenson, Anna J; Goss, Christopher H

2015-09-01

The extent to which sweat chloride concentration predicts survival and clinical phenotype independently of CFTR genotype in cystic fibrosis is not well understood. We analyzed the US Cystic Fibrosis Foundation Patient Registry data using Cox regression to examine the relationship between sweat chloride concentration (<60, 60-<80, ≥80mmol/L), CFTR genotype (high and lower risk for lung function decline), and survival and mixed linear regression to examine the relationship between sweat chloride, CFTR genotype, and measures of lung function and growth. When included in the same model, CFTR genotype, but not sweat chloride, was independently associated with survival and with lung function, height, and BMI. Among patients with unclassified CFTR genotype, sweat chloride was an independent predictor of survival (<60 HR 0.53 [0.37, 0.77], 60-<80 0.51 [0.42, 0.63]). Sweat chloride concentration may be a useful predictor of mortality and clinical phenotype when CFTR genotype functional class is unclassified. Copyright © 2015 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Sweating Like a Pig: Physics or Irony?

NASA Astrophysics Data System (ADS)

Bohren, Craig F.

2016-03-01

In his interesting and informative book Is That a Fact?, Joe Schwarcz avers that pigs do not sweat and the saying "sweating like a pig" originates in iron smelting. Oblong pieces of hot iron, with a fancied resemblance to a sow with piglets, cool in sand to the dew point of the surrounding air, and hence water condenses on the "pig." But this explanation, which I have seen on the Internet, lacks a few caveats. It implies that molten iron, solidifying and cooling, anywhere, anytime, accretes liquid water, as if this were a special property of cooling iron. Set aside that real pigs sweat perceptibly from their snouts; kiss a pig and verify for yourself. Pigs also sweat imperceptibly. Imperceptible (insensible) perspiration is water vapor from the skin and lungs exuded without sensible condensation. That from humans is about 1 liter/day. Sweat is 99% liquid water, NaCl the dominant solute, secreted quickly, sometimes profusely, by subcutaneous sweat glands in response to thermal stress, in contrast to the slow, continuous diffusion of water vapor through skin.

Thermophysiological responses induced by a body heat removal system with Peltier devices in a hot environment.

PubMed

Suzurikawa, Jun; Fujimoto, Sho; Mikami, Kousei; Jonai, Hiroshi; Inoue, Takenobu

2013-01-01

Individuals with spinal cord injuries often experience thermoregulation disorders as well as sensory and motor disabilities. In order to prevent such individuals from becoming hyperthermic, we developed a body heat removal system (BHRS) with thermoelectric devices. Our BHRS comprises four Peltier devices mounted on a wheelchair backrest and continuously transfers body heat through the contacting interface to the external environment. Here, we characterized thermophysiological responses induced by this novel contact-type cooling system. A cooling experiment in a hot environment with five able-bodied subjects demonstrated that sweating and systolic blood pressure in the back-cooling (BC) trial were significantly suppressed compared with those in no-cooling (NC) trial, while no difference was found in oral and skin temperatures. A correlation was observed between chest skin temperature and blood flow in the NC trial; this was not observed in the BC trial. These results suggest that BHRS modulates normal thermoregulatory responses, including sweating and vascular dilation and has the capability to partly replace these functions.

Mycobacterium Tuberculosis Infection within a Warthin Tumor: A Case Report and Literature Review.

PubMed

Ulusan, Murat; Abul, Yasin; Bakır, Sule

2013-10-01

The co-existence of tuberculosis and a Warthin tumor in the parotid gland is extremely rare. A 46-year-old male presented with a mass in the left parotid region of 6-month duration. The patient's history was only remarkable for a facial swelling, night sweats and a 38.5 C° fever. A 2 × 3-cm mobile, non-tender, mass with a smooth surface was palpated on left parotid tail. CT examination showed a well-defined 30 mm in diameter tumor mass in the left superficial lobe of the parotid gland. A superficial parotidectomy was performed. The final pathological diagnosis of the parotidectomy specimen was reported as a Warthin tumor and epitheloid granulomas with caseification necrosis. Purified protein derivative (PPD) was 30 mm in enduration. Two weeks after the antituberculosis treatment fever declined to normal values and night sweats decreased. Tuberculosis can also be seen in parotid tumors which can coexist or mimic pleomorphic adenoma, Warthin tumor.

Can the RUVIS reflected UV imaging system visualize fingerprint corrosion on brass cartridge casings postfiring?

PubMed

Leintz, Rachel; Bond, John W

2013-05-01

Comparisons are made between the visualization of fingerprint corrosion ridge detail on fired brass cartridge casings, where fingerprint sweat was deposited prefiring, using both ultraviolet (UV) and visible (natural daylight) light sources. A reflected ultraviolet imaging system (RUVIS), normally used for visualizing latent fingerprint sweat deposits, is compared with optical interference and digital color mapping of visible light, the latter using apparatus constructed to easily enable selection of the optimum viewing angle. Results show that reflected UV, with a monochromatic UV source of 254 nm, was unable to visualize fingerprint ridge detail on any of 12 casings analyzed, whereas optical interference and digital color mapping using natural daylight yielded ridge detail on three casings. Reasons for the lack of success with RUVIS are discussed in terms of the variation in thickness of the thin film of metal oxide corrosion and absorption wavelengths for the corrosion products of brass. © 2013 American Academy of Forensic Sciences.

[A man with persisting fever, night sweats and high sedimentation rate].

PubMed

Kildahl-Andersen, Odd; Murbræch, Klaus; Skudal, Hilde; Stalsberg, Helge

2011-11-29

Fever of unknown origin and high sedimentation rate are common clinical problems. A middle-aged man with fever of unknown origin, night sweats and high sedimentation rate was referred to our hospital for investigation. The patient was suspected to have mononucleosis or reactivation of infectious mononucleosis because of mild anaemia and thrombocytopenia, a weakly positive IgM antibody test for Epstein-Barr virus and monocytosis (in peripheral blood). Because monocytosis, elevated sedimentation rate and fever persisted, bone marrow smears were prepared and biopsies taken.The third biopsy showed that morphology was consistent with chronic myelomonocytic leukemia (CMML), which was confirmed by two later biopsies. However, a malignant cell population (consisting of blasts in peripheral blood) was only found in one of several flow cytometry assessments of peripheral blood and bone marrow aspirate and cytogenetic analyses of bone marrow cells were normal. The patient's clinical situation has been stable for some years and treatment has not been necessary.

Development of a screening system for cystic fibrosis.

PubMed

Coury, A J; Fogt, E J; Norenberg, M S; Untereker, D F

1983-09-01

We have developed a simple method for detecting high concentrations of chloride in sweat from ambulatory subjects, a measurement useful in the detection of cystic fibrosis. The method is based on the standard approach of stimulating sweat generation through iontophoresis of pilocarpine nitrate into the skin, followed by collection and analysis of the sweat for chloride concentration. The sweat-stimulating reagents are contained in polymeric gel pads, which are used in conjunction with a small battery-powered stimulator. The chloride analysis is subsequently done on the stimulated site by use of a thin test patch that picks up a fixed amount of sweat and changes color if the chloride concentration is higher than a predetermined value. The successful completion of a test is indicated by a fill tab, which changes color when the appropriate amount of sweat has been picked up by the chloride test patch.

Evidence for β-adrenergic modulation of sweating during incremental exercise in habitually trained males.

PubMed

Amano, Tatsuro; Shitara, Yosuke; Fujii, Naoto; Inoue, Yoshimitsu; Kondo, Narihiko

2017-07-01

The aim of the present study was to determine the β-adrenergic contribution to sweating during incremental exercise in habitually trained males. Nine habitually trained and 11 untrained males performed incremental cycling until exhaustion (20 W/min). Bilateral forearm sweat rates (ventilated capsule) were measured at two skin sites that were transdermally administered via iontophoresis with either 1% propranolol (Propranolol, a nonselective β-adrenergic receptor antagonist) or saline (Control). The sweat rate was evaluated as a function of both relative (percentage of maximum workload) and absolute exercise intensities. The sweat rate at the Propranolol site was lower than the control during exercise at 80 (0.57 ± 0.21 and 0.45 ± 0.19 mg·cm -2 ·min -1 for Control and Propranolol, respectively) and 90% (0.74 ± 0.22 and 0.65 ± 0.17 mg·cm -2 ·min -1 , respectively) of maximum workload in trained males (all P < 0.05). By contrast, no between-site differences in sweat rates were observed in untrained counterparts (all P > 0.05). At the same absolute intensity, higher sweat rates on the control site were observed in trained males relative to the untrained during exercise at 160 (0.23 ± 0.20 and 0.04 ± 0.05 mg·cm -2 ·min -1 for trained and untrained, respectively) and 180 W (0.40 ± 0.20 and 0.13 ± 0.13 mg·cm -2 ·min -1 , respectively) (all P < 0.05), whereas this between-group difference was not observed at the Propranolol site (all P > 0.05). We show that the β-adrenergic mechanism does modulate sweating during exercise at a submaximal high relative intensity in habitually trained males. The β-adrenergic mechanism may in part contribute to the greater sweat production in habitually trained males than in untrained counterparts during exercise. NEW & NOTEWORTHY We demonstrated for the first time that the β-adrenergic mechanism does modulate sweating (i.e., β-adrenergic sweating) during exercise using a localized β-adrenoceptor blockade in humans in vivo. β-Adrenergic sweating was evident in habitually trained individuals during exercise at a submaximal high relative intensity (80-90% maximal work). This observation advances our understanding of human thermoregulation during exercise and of the mechanism that underlies sweat gland adaptation to habitual exercise training. Copyright © 2017 the American Physiological Society.

Menopausal syndrome limited to hot flushes and sweating a representative survey study.

PubMed

Weidner, Kerstin; Croy, Ilona; Siepmann, Timo; Brähler, Elmar; Beutel, Manfred; Bittner, Antje

2017-09-01

The menopausal syndrome is described as a series of various physical and nonphysical symptoms attributed to perimenopausal changes in hormone levels. However, evidence is biased by focusing research on the target group of middle aged women only. To overcome this bias, we examined the occurrence of menopausal symptoms during the entire life span in both women and men. Therefore, we studied the occurrence of menopausal symptoms with the widely used Menopause Rating Scale (MRS) across the entire life span in both women and men. To this end, we performed a nationwide cross-sectional survey study in Germany in which we examined a representative sample of 2527 persons aged from 14 to 95 years. Additionally, sociodemographic factors and self-efficacy were surveyed. Although the overall MRS score was generally higher for women compared to men, there was no specific peak for the time of menopause. Instead the score increased linearly with age for both sexes. Furthermore, it was stronger associated with sociodemographic variables and self-efficacy than with the sex of the participants. Among all assessed symptoms, only hot flushes and sweating, but none of the others, emerged as specific for the menopausal episode. Our data indicate that among symptoms commonly classified as menopausal only hot flushes and sweating appear to be specific for the perimenopausal episode. Other symptoms may be caused by a multifactorial etiopathogenesis including physical, sociodemographic, cultural and psychological factors that, in turn, might benefit from multimodal treatment regimes.

Does anticipatory sweating occur prior to fluid consumption?

PubMed

Wing, David; McClintock, Rebecca; Plumlee, Deva; Rathke, Michelle; Burnett, Tim; Lyons, Bailey; Buono, Michael J

2012-01-01

The purpose of this study was to examine if anticipatory sweating occurs prior to fluid consumption in dehydrated subjects. It was hypothesized that there would first be an anticipatory response to the sight of water, and then with drinking, a second response caused by mechanical stimulation of oropharyngeal nerves. Dehydrated subjects (n=19) sat in a heat chamber for 30 minutes. At minute 15, a resistance hygrometer capsule was attached and sweat rate was measured every 3 seconds. At minute 35:00, a researcher entered the room with previously measured water (2 ml/kg euhydrated body weight). At minute 35:30, the subject was allowed to drink. Data collection continued for 5 minutes post consumption. As expected, 16 of the 19 subjects responded to oropharyngeal stimuli with increased sweat rate. However, the new finding was that a majority (12 of 19) also showed an anticipatory sweating response prior to fluid consumption. Subjects were divided into 4 groups based on the magnitude of the sweating response. Strong responders' (n=4) anticipatory response accounted for 50% or more of the total change in sweat rate. Moderate responders' (n=4) anticipatory response accounted for 20%-49%. Weak responders' (n=4) anticipatory response accounted for 6-20%. Finally, non-responders (n=7) showed no anticipatory response. Although previously noted anecdotally in the literature, the current study is the first to demonstrate that measurable anticipatory sweating occurs prior to fluid intake in dehydrated subjects in a significant percentage of the population. Such data suggests that cerebral input, like oropharyngeal stimulation, can temporarily remove the dehydration-induced inhibition of sweating.

Does Replacing Sodium Excreted in Sweat Attenuate the Health Benefits of Physical Activity?

PubMed

Turner, Martin J; Avolio, Alberto P

2016-08-01

International guidelines suggest limiting sodium intake to 86-100 mmol/day, but average intake exceeds 150 mmol/day. Participants in physical activities are, however, advised to increase sodium intake before, during and after exercise to ensure euhydration, replace sodium lost in sweat, speed rehydration and maintain performance. A similar range of health benefits is attributable to exercise and to reduction in sodium intake, including reductions in blood pressure (BP) and the increase of BP with age, reduced risk of stroke and other cardiovascular diseases, and reduced risk of osteoporosis and dementia. Sweat typically contains 40-60 mmol/L of sodium, leading to approximately 20-90 mmol of sodium lost in one exercise session with sweat rates of 0.5-1.5 L/h. Reductions in sodium intake of 20-90 mmol/day have been associated with substantial health benefits. Homeostatic systems reduce sweat sodium as low as 3-10 mmol/L to prevent excessive sodium loss. "Salty sweaters" may be individuals with high sodium intake who perpetuate their "salty sweat" condition by continual replacement of sodium excreted in sweat. Studies of prolonged high intensity exercise in hot environments suggest that sodium supplementation is not necessary to prevent hyponatremia during exercise lasting up to 6 hr. We examine the novel hypothesis that sodium excreted in sweat during physical activity offsets a significant fraction of excess dietary sodium, and hence may contribute part of the health benefits of exercise. Replacing sodium lost in sweat during exercise may improve physical performance, but may attenuate the long-term health benefits of exercise.

Effects of Immediate Telephone Follow-Up with Providers on Sweat Chloride Test Timing after Cystic Fibrosis Newborn Screening Identifies a Single Mutation

PubMed Central

La Pean, Alison; Farrell, Michael H.; Eskra, Kerry L.; Farrell, Philip M.

2012-01-01

Objectives To assess whether reporting “possible cystic fibrosis (CF)” newborn screening (NBS) results via fax plus simultaneous telephone contact with primary care providers (PCPs), versus fax alone, influenced three outcomes: getting a sweat chloride test, age at sweat chloride test, and sweat-testing before 8 weeks old. Study Design Retrospective cohort comparison of infants born in Wisconsin whose PCPs received telephone intervention (n=301), versus recent historical controls whose PCP did not (n=355). Intervention data were collected during a longitudinal research and quality improvement effort; de-identified comparison data were constructed from auxiliary NBS tracking information. Parametric and nonparametric statistical analyses tested for group differences. Results Most infants (92%) with “possible CF” NBS results whose PCPs lacked telephone intervention ultimately underwent sweat-testing, underlining efficacy for fax-only reporting. Telephone intervention was significantly associated with improvements in infants undergoing sweat-testing at both ≤6 and <8 weeks and a slight, but non-significant, 3.5-day reduction in infants’ age at sweat-testing. The effect of telephone intervention was greater for PCPs whose patients underwent sweat-testing at community-affiliated medical centers versus academic medical centers (p=0.008). Conclusion Reporting “possible CF” NBS results via fax plus simultaneous telephone follow-up with PCPs increases the number of infants who have sweat chloride tests before 8 weeks of age, when affected infants are more likely to receive full benefits of early diagnosis and treatment. PMID:23102590

Sweat Gland Progenitors in Development, Homeostasis, and Wound Repair

PubMed Central

Lu, Catherine; Fuchs, Elaine

2014-01-01

The human body is covered with several million sweat glands. These tiny coiled tubular skin appendages produce the sweat that is our primary source of cooling and hydration of the skin. Numerous studies have been published on their morphology and physiology. Until recently, however, little was known about how glandular skin maintains homeostasis and repairs itself after tissue injury. Here, we provide a brief overview of sweat gland biology, including newly identified reservoirs of stem cells in glandular skin and their activation in response to different types of injuries. Finally, we discuss how the genetics and biology of glandular skin has advanced our knowledge of human disorders associated with altered sweat gland activity. PMID:24492848

Multidimensional Raman spectroscopic signature of sweat and its potential application to forensic body fluid identification.

PubMed

Sikirzhytski, Vitali; Sikirzhytskaya, Aliaksandra; Lednev, Igor K

2012-03-09

This proof-of-concept study demonstrated the potential of Raman microspectroscopy for nondestructive identification of traces of sweat for forensic purposes. Advanced statistical analysis of Raman spectra revealed that dry sweat was intrinsically heterogeneous, and its biochemical composition varies significantly with the donor. As a result, no single Raman spectrum could adequately represent sweat traces. Instead, a multidimensional spectroscopic signature of sweat was built that allowed for the presentation of any single experimental spectrum as a linear combination of two fluorescent backgrounds and three Raman spectral components dominated by the contribution from lactate, lactic acid, urea and single amino acids. Copyright © 2011 Elsevier B.V. All rights reserved.

Chemosignals of stress influence social judgments.

PubMed

Dalton, Pamela; Mauté, Christopher; Jaén, Cristina; Wilson, Tamika

2013-01-01

Human body odors have important communicative functions regarding genetic identity, immune fitness and general health, but an expanding body of research suggests they can also communicate information about an individual's emotional state. In the current study, we tested whether axillary odors obtained from women experiencing psychosocial stress could negatively influence personality judgments of warmth and competence made about other women depicted in video scenarios. 44 female donors provided three types of sweat samples: untreated exercise sweat, untreated stress sweat and treated stress sweat. After a 'washout' period, a commercial unscented anti-perspirant product was applied to the left axilla only to evaluate whether 'blocking' the stress signal would improve the social evaluations. A separate group of male and female evaluators (n = 120) rated the women in the videos while smelling one of the three types of sweat samples. Women in the video scenes were rated as being more stressed by both men and women when smelling the untreated vs. treated stress sweat. For men only, the women in the videos were rated as less confident, trustworthy and competent when smelling both the untreated stress and exercise sweat in contrast to the treated stress sweat. Women's social judgments were unaffected by sniffing the pads. The results have implications for influencing multiple types of professional and personal social interactions and impression management and extend our understanding of the social communicative function of body odors.

A Proteomic Analysis of Eccrine Sweat: Implications for the Discovery of Schizophrenia Biomarker Proteins

PubMed Central

Raiszadeh, Michelle M.; Ross, Mark M.; Russo, Paul S.; Schaepper, Mary Ann H.; Zhou, Weidong; Deng, Jianghong; Ng, Daniel; Dickson, April; Dickson, Cindy; Strom, Monica; Osorio, Carolina; Soeprono, Thomas; Wulfkuhle, Julia D.; Kabbani, Nadine; Petricoin, Emanuel F.; Liotta, Lance A.; Kirsch, Wolff M.

2012-01-01

Liquid chromatography tandem mass spectrometry (LC-MS/MS) and multiple reaction monitoring mass spectrometry (MRM-MS) proteomics analyses were performed on eccrine sweat of healthy controls, and the results were compared with those from individuals diagnosed with schizophrenia (SZ). This is the first large scale study of the sweat proteome. First, we performed LC-MS/MS on pooled SZ samples and pooled control samples for global proteomics analysis. Results revealed a high abundance of diverse proteins and peptides in eccrine sweat. Most of the proteins identified from sweat samples were found to be different than the most abundant proteins from serum, which indicates that eccrine sweat is not simply a plasma transudate, and may thereby be a source of unique disease-associated biomolecules. A second independent set of patient and control sweat samples were analyzed by LC-MS/MS and spectral counting to determine qualitative protein differential abundances between the control and disease groups. Differential abundances of selected proteins, initially determined by spectral counting, were verified by MRM-MS analyses. Seventeen proteins showed a differential abundance of approximately two-fold or greater between the SZ pooled sample and the control pooled sample. This study demonstrates the utility of LC-MS/MS and MRM-MS as a viable strategy for the discovery and verification of potential sweat protein disease biomarkers. PMID:22256890

Prolonged head-down tilt exposure reduces maximal cutaneous vasodilator and sweating capacity in humans

NASA Technical Reports Server (NTRS)

Crandall, C. G.; Shibasaki, M.; Wilson, T. E.; Cui, J.; Levine, B. D.

2003-01-01

Cutaneous vasodilation and sweat rate are reduced during a thermal challenge after simulated and actual microgravity exposure. The effects of microgravity exposure on cutaneous vasodilator capacity and on sweat gland function are unknown. The purpose of this study was to test the hypothesis that simulated microgravity exposure, using the 6 degrees head-down tilt (HDT) bed rest model, reduces maximal forearm cutaneous vascular conductance (FVC) and sweat gland function and that exercise during HDT preserves these responses. To test these hypotheses, 20 subjects were exposed to 14 days of strict HDT bed rest. Twelve of those subjects exercised (supine cycle ergometry) at 75% of pre-bed rest heart rate maximum for 90 min/day throughout HDT bed rest. Before and after HDT bed rest, maximal FVC was measured, via plethysmography, by heating the entire forearm to 42 degrees C for 45 min. Sweat gland function was assessed by administering 1 x 10(-6) to 2 M acetylcholine (9 doses) via intradermal microdialysis while simultaneously monitoring sweat rate over the microdialysis membranes. In the nonexercise group, maximal FVC and maximal stimulated sweat rate were significantly reduced after HDT bed rest. In contrast, these responses were unchanged in the exercise group. These data suggest that 14 days of simulated microgravity exposure, using the HDT bed rest model, reduces cutaneous vasodilator and sweating capacity, whereas aerobic exercise training during HDT bed rest preserves these responses.

Eccrine sweat gland development and sweat secretion

PubMed Central

Cui, Chang-Yi; Schlessinger, David

2017-01-01

Eccrine sweat glands help to maintain homoeostasis, primarily by stabilizing body temperature. Derived from embryonic ectoderm, millions of eccrine glands are distributed across human skin and secrete litres of sweat per day. Their easy accessibility has facilitated the start of analyses of their development and function. Mouse genetic models find sweat gland development regulated sequentially by Wnt, Eda and Shh pathways, although precise subpathways and additional regulators require further elucidation. Mature glands have two secretory cell types, clear and dark cells, whose comparative development and functional interactions remain largely unknown. Clear cells have long been known as the major secretory cells, but recent studies suggest that dark cells are also indispensable for sweat secretion. Dark cell-specific Foxa1 expression was shown to regulate a Ca2+-dependent Best2 anion channel that is the candidate driver for the required ion currents. Overall, it was shown that cholinergic impulses trigger sweat secretion in mature glands through second messengers – for example InsP3 and Ca2+ – and downstream ion channels/transporters in the framework of a Na+-K+-Cl− cotransporter model. Notably, the microenvironment surrounding secretory cells, including acid–base balance, was implicated to be important for proper sweat secretion, which requires further clarification. Furthermore, multiple ion channels have been shown to be expressed in clear and dark cells, but the degree to which various ion channels function redundantly or indispensably also remains to be determined. PMID:26014472

Consistency between Sweat Rate and Wet Bulb Globe Temperature for the Assessment of Heat Stress of People Working Outdoor in Arid and Semi-arid Regions.

PubMed

Heidari, Hamidreza; Golbabaei, Farideh; Shamsipour, Aliakbar; Rahimi Forushani, Abbas; Gaeini, Abbasali

2018-01-01

Heat stress is common among workers in arid and semi-arid areas. In order to take every preventive measure to protect exposed workers against heat-related disorders, it is crucial to choose an appropriate index that accurately relates environmental parameters to physiological responses. To investigate the consistency between 2 heat stress and strain indices, ie , sweat rate and wet bulb globe temperature (WBGT), for the assessment of heat stress of people working outdoor in arid and semi-arid regions in Iran. During spring and summer, 136 randomly selected outdoor workers were enrolled in this study. Using a defined protocol, the sweat rate of these workers was measured 3 times a day. Simultaneously, the environmental parameters including WBGT index were recorded for each working station. The level of agreement between sweat rate and WBGT was poor ( κ <0.2). Based on sweat rate, no case exceeding the reference value was observed during the study. WBGT overestimated the heat stress in outdoor workers compared to sweat rate. It seems that the sweat rate standards may need some modifications related to real condition of work in arid and semi-arid regions in Iran. Moreover, it seems that judging workers solely based on monitoring their sweat rate in such regions, can probably result in underestimation of heat stress.

Regional variations in transepidermal water loss, eccrine sweat gland density, sweat secretion rates and electrolyte composition in resting and exercising humans

PubMed Central

2013-01-01

Literature from the past 168 years has been filtered to provide a unified summary of the regional distribution of cutaneous water and electrolyte losses. The former occurs via transepidermal water vapour diffusion and secretion from the eccrine sweat glands. Daily insensible water losses for a standardised individual (surface area 1.8 m2) will be 0.6–2.3 L, with the hands (80–160 g.h−1) and feet (50–150 g.h−1) losing the most, the head and neck losing intermediate amounts (40–75 g.h−1) and all remaining sites losing 15–60 g.h−1. Whilst sweat gland densities vary widely across the skin surface, this same individual would possess some 2.03 million functional glands, with the highest density on the volar surfaces of the fingers (530 glands.cm−2) and the lowest on the upper lip (16 glands.cm−2). During passive heating that results in a resting whole-body sweat rate of approximately 0.4 L.min−1, the forehead (0.99 mg.cm−2.min−1), dorsal fingers (0.62 mg.cm−2.min−1) and upper back (0.59 mg.cm−2.min−1) would display the highest sweat flows, whilst the medial thighs and anterior legs will secrete the least (both 0.12 mg.cm−2.min−1). Since sweat glands selectively reabsorb electrolytes, the sodium and chloride composition of discharged sweat varies with secretion rate. Across whole-body sweat rates from 0.72 to 3.65 mg.cm−2.min−1, sodium losses of 26.5–49.7 mmol.L−1 could be expected, with the corresponding chloride loss being 26.8–36.7 mmol.L−1. Nevertheless, there can be threefold differences in electrolyte losses across skin regions. When exercising in the heat, local sweat rates increase dramatically, with regional glandular flows becoming more homogeneous. However, intra-regional evaporative potential remains proportional to each local surface area. Thus, there is little evidence that regional sudomotor variations reflect an hierarchical distribution of sweating either at rest or during exercise. PMID:23849497

Variability of sweat chloride concentration in subjects with cystic fibrosis and G551D mutations.

PubMed

Vermeulen, F; Le Camus, C; Davies, J C; Bilton, D; Milenković, D; De Boeck, K

2017-01-01

Sweat chloride concentration, a biomarker of CFTR function, is an appropriate outcome parameter in clinical trials aimed at correcting the basic CF defect. Although there is consensus on a cut-off value to diagnose CF, we have only limited information on the within subject variability of sweat chloride over time. Such information would be useful for sample size calculations in clinical trials. Therefore, we retrospectively analyzed repeated sweat chloride values obtained in patients with G551D mutation(s) assigned to placebo in an ivacaftor interventional trial. In subjects with G551D at least 12years of age, a pilocarpine sweat test using Macroduct collector was taken on both arms at 8 time points over 48weeks. We explored 1062 pilocarpine sweat test values obtained in 78 placebo patients of the VX08-770-102 trial. Mean overall sweat chloride value (all patients, all tests, n=1062) was 100.8mmol/L (SD 12.7mmol/L). Using a multilevel mixed model, the between-subject standard deviation (SD) for sweat chloride was 8.9mmol/L (95% CI 7.4-10.6) and within-subject SD was 8.1mmol/L (95% CI 7.5-8.7). Limits of repeatability for repeat measurements were -19.7 to +21.6mmol/L using values from one arm, and -13.3 to 11.8mmol/L using mean of values obtained at 4 test occasions. Sample size calculations showed that the minimal treatment effect on sweat chloride concentration that can be demonstrated for a group of 5 patients is around 15mmol/L, using a cross-over design and combinations of 4 tests for each phase of the trial. Although the sweat test is considered a robust measure, sweat chloride measurements in patients with CF and a G551D mutation had an inherent biological variability that is higher than commonly considered. Further analyses of placebo group data are crucial to learn more about the natural variability of this outcome parameter. Copyright © 2016 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Surface contamination artificially elevates initial sweat mineral concentrations

USDA-ARS?s Scientific Manuscript database

During exercise in the heat, sweat is initially concentrated in minerals, but serial sweat samples appear more dilute. Possible causes include reduced dermal mineral concentrations or flushing of surface contamination. PURPOSE: To simultaneously sample mineral concentrations in transdermal fluid (T...

The Sweat Metabolome of Screen-Positive Cystic Fibrosis Infants: Revealing Mechanisms beyond Impaired Chloride Transport

PubMed Central

2017-01-01

The sweat chloride test remains the gold standard for confirmatory diagnosis of cystic fibrosis (CF) in support of universal newborn screening programs. However, it provides ambiguous results for intermediate sweat chloride cases while not reflecting disease progression when classifying the complex CF disease spectrum given the pleiotropic effects of gene modifiers and environment. Herein we report the first characterization of the sweat metabolome from screen-positive CF infants and identify metabolites associated with disease status that complement sweat chloride testing. Pilocarpine-stimulated sweat specimens were collected independently from two CF clinics, including 50 unaffected infants (e.g., carriers) and 18 confirmed CF cases. Nontargeted metabolite profiling was performed using multisegment injection–capillary electrophoresis–mass spectrometry as a high throughput platform for analysis of polar/ionic metabolites in volume-restricted sweat samples. Amino acids, organic acids, amino acid derivatives, dipeptides, purine derivatives, and unknown exogenous compounds were identified in sweat when using high resolution tandem mass spectrometry, including metabolites associated with affected yet asymptomatic CF infants, such as asparagine and glutamine. Unexpectedly, a metabolite of pilocarpine, used to stimulate sweat secretion, pilocarpic acid, and a plasticizer metabolite from environmental exposure, mono(2-ethylhexyl)phthalic acid, were secreted in the sweat of CF infants at significantly lower concentrations relative to unaffected CF screen-positive controls. These results indicated a deficiency in human paraoxonase, an enzyme unrelated to mutations to the cystic fibrosis transmembrane conductance regulator (CFTR) and impaired chloride transport, which is a nonspecific arylesterase/lactonase known to mediate inflammation, bacterial biofilm formation, and recurrent lung infections in affected CF children later in life. This work sheds new light into the underlying mechanisms of CF pathophysiology as required for new advances in precision medicine of orphan diseases that benefit from early detection and intervention, including new molecular targets for therapeutic intervention. PMID:28852705

Sweat conductivity: an accurate diagnostic test for cystic fibrosis?

PubMed

Mattar, Ana Claudia Veras; Leone, Claudio; Rodrigues, Joaquim Carlos; Adde, Fabíola Villac

2014-09-01

Sweat chloride test is the gold standard test for cystic fibrosis (CF) diagnosis. Sweat conductivity is widely used although still considered a screening test. This was a prospective, cross-sectional, diagnostic research conducted at the laboratory of the Instituto da Criança of the Hospital das Clínicas, São Paulo, Brazil. Sweat chloride (quantitative pilocarpine iontophoresis) and sweat conductivity tests were simultaneously performed in patients referred for a sweat test between March 2007 and October 2008. Conductivity and chloride cut-off values used to rule out or diagnose CF were <75 and ≥90 mmol/L and <60 and ≥60 mmol/L, respectively. The ROC curve method was used to calculate the sensitivity, specificity, positive (PPV) and negative predictive value (NPV), as well as the respective 95% confidence intervals and to calculate the area under the curve for both tests. The kappa coefficient was used to evaluate agreement between the tests. Both tests were performed in 738 children, and CF was ruled out in 714 subjects; the median sweat chloride and conductivity values were 11 and 25 mmol/L in these populations, respectively. Twenty-four patients who had received a diagnosis of CF presented median sweat chloride and conductivity values of 87 and 103 mmol/L, respectively. Conductivity values above 90 mmol/L had 83.3% sensitivity, 99.7% specificity, 90.9% PPV and 99.4% NPV to diagnose CF. The best conductivity cut-off value to exclude CF was <75 mmol/L. Good agreement was observed between the tests (kappa: 0.934). The sweat conductivity test yielded a high degree of diagnostic accuracy and it showed good agreement with sweat chloride. We suggest that it should play a role as a diagnostic test for CF in the near future. Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

The Sweat Metabolome of Screen-Positive Cystic Fibrosis Infants: Revealing Mechanisms beyond Impaired Chloride Transport.

PubMed

Macedo, Adriana N; Mathiaparanam, Stellena; Brick, Lauren; Keenan, Katherine; Gonska, Tanja; Pedder, Linda; Hill, Stephen; Britz-McKibbin, Philip

2017-08-23

The sweat chloride test remains the gold standard for confirmatory diagnosis of cystic fibrosis (CF) in support of universal newborn screening programs. However, it provides ambiguous results for intermediate sweat chloride cases while not reflecting disease progression when classifying the complex CF disease spectrum given the pleiotropic effects of gene modifiers and environment. Herein we report the first characterization of the sweat metabolome from screen-positive CF infants and identify metabolites associated with disease status that complement sweat chloride testing. Pilocarpine-stimulated sweat specimens were collected independently from two CF clinics, including 50 unaffected infants (e.g., carriers) and 18 confirmed CF cases. Nontargeted metabolite profiling was performed using multisegment injection-capillary electrophoresis-mass spectrometry as a high throughput platform for analysis of polar/ionic metabolites in volume-restricted sweat samples. Amino acids, organic acids, amino acid derivatives, dipeptides, purine derivatives, and unknown exogenous compounds were identified in sweat when using high resolution tandem mass spectrometry, including metabolites associated with affected yet asymptomatic CF infants, such as asparagine and glutamine. Unexpectedly, a metabolite of pilocarpine, used to stimulate sweat secretion, pilocarpic acid, and a plasticizer metabolite from environmental exposure, mono(2-ethylhexyl)phthalic acid, were secreted in the sweat of CF infants at significantly lower concentrations relative to unaffected CF screen-positive controls. These results indicated a deficiency in human paraoxonase, an enzyme unrelated to mutations to the cystic fibrosis transmembrane conductance regulator (CFTR) and impaired chloride transport, which is a nonspecific arylesterase/lactonase known to mediate inflammation, bacterial biofilm formation, and recurrent lung infections in affected CF children later in life. This work sheds new light into the underlying mechanisms of CF pathophysiology as required for new advances in precision medicine of orphan diseases that benefit from early detection and intervention, including new molecular targets for therapeutic intervention.

Human Excretion of Bisphenol A: Blood, Urine, and Sweat (BUS) Study

PubMed Central

Genuis, Stephen J.; Beesoon, Sanjay; Birkholz, Detlef; Lobo, Rebecca A.

2012-01-01

Background. Bisphenol A (BPA) is an ubiquitous chemical contaminant that has recently been associated with adverse effects on human health. There is incomplete understanding of BPA toxicokinetics, and there are no established interventions to eliminate this compound from the human body. Using 20 study participants, this study was designed to assess the relative concentration of BPA in three body fluids—blood, urine, and sweat—and to determine whether induced sweating may be a therapeutic intervention with potential to facilitate elimination of this compound. Methods. Blood, urine, and sweat were collected from 20 individuals (10 healthy participants and 10 participants with assorted health problems) and analyzed for various environmental toxicants including BPA. Results. BPA was found to differing degrees in each of blood, urine, and sweat. In 16 of 20 participants, BPA was identified in sweat, even in some individuals with no BPA detected in their serum or urine samples. Conclusions. Biomonitoring of BPA through blood and/or urine testing may underestimate the total body burden of this potential toxicant. Sweat analysis should be considered as an additional method for monitoring bioaccumulation of BPA in humans. Induced sweating appears to be a potential method for elimination of BPA. PMID:22253637

Sweat lipid mediator profiling: a noninvasive approach for cutaneous research[S

PubMed Central

Hassoun, Lauren A.; Foolad, Negar; Pedersen, Theresa L.; Sivamani, Raja K.; Newman, John W.

2017-01-01

Recent advances in analytical and sweat collection techniques provide new opportunities to identify noninvasive biomarkers for the study of skin inflammation and repair. This study aims to characterize the lipid mediator profile including oxygenated lipids, endocannabinoids, and ceramides/sphingoid bases in sweat and identify differences in these profiles between sweat collected from nonlesional sites on the unflared volar forearm of subjects with and without atopic dermatitis (AD). Adapting routine procedures developed for plasma analysis, over 100 lipid mediators were profiled using LC-MS/MS and 58 lipid mediators were detected in sweat. Lipid mediator concentrations were not affected by sampling or storage conditions. Increases in concentrations of C30–C40 [NS] and [NdS] ceramides, and C18:1 sphingosine, were observed in the sweat of study participants with AD despite no differences being observed in transepidermal water loss between study groups, and this effect was strongest in men (P < 0.05, one-way ANOVA with Tukey’s post hoc HSD). No differences in oxylipins and endocannabinoids were observed between study groups. Sweat mediator profiling may therefore provide a noninvasive diagnostic for AD prior to the presentation of clinical signs. PMID:27875258

Sweat lipid mediator profiling: a noninvasive approach for cutaneous research.

PubMed

Agrawal, Karan; Hassoun, Lauren A; Foolad, Negar; Pedersen, Theresa L; Sivamani, Raja K; Newman, John W

2017-01-01

Recent advances in analytical and sweat collection techniques provide new opportunities to identify noninvasive biomarkers for the study of skin inflammation and repair. This study aims to characterize the lipid mediator profile including oxygenated lipids, endocannabinoids, and ceramides/sphingoid bases in sweat and identify differences in these profiles between sweat collected from nonlesional sites on the unflared volar forearm of subjects with and without atopic dermatitis (AD). Adapting routine procedures developed for plasma analysis, over 100 lipid mediators were profiled using LC-MS/MS and 58 lipid mediators were detected in sweat. Lipid mediator concentrations were not affected by sampling or storage conditions. Increases in concentrations of C30-C40 [NS] and [NdS] ceramides, and C18:1 sphingosine, were observed in the sweat of study participants with AD despite no differences being observed in transepidermal water loss between study groups, and this effect was strongest in men (P < 0.05, one-way ANOVA with Tukey's post hoc HSD). No differences in oxylipins and endocannabinoids were observed between study groups. Sweat mediator profiling may therefore provide a noninvasive diagnostic for AD prior to the presentation of clinical signs.

Cells in 3D-reconstitutued eccrine sweat gland cell spheroids differentiate into gross cystic disease fluid protein 15-expressing dark secretory cells and carbonic anhydrase II-expressing clear secretory cells.

PubMed

Li, Haihong; Chen, Liyun; Zhang, Mingjun; Zhang, Bingna

2017-07-01

Secretory coils of eccrine sweat glands are composed of myoepithelial cells, dark secretory cells and clear secretory cells. The two types of cells play important roles in sweat secretion. In our previous study, we demonstrated that the 3D-reconstituted eccrine sweat gland cell spheroids differentiate into secretory coil-like structures. However, whether the secretory coil-like structures further differentiate into dark secretory cells and clear secretory cells were is still unknown. In this study, we detected the differentiation of clear and dark secretory cells in the 3D-reconstituted eccrine sweat gland cell spheroids using the dark secretory cell-specific marker, GCDFP-15, and clear secretory cell-specific marker, CAII by immunofluorescence staining. Results showed that there were both GCDFP-15- and CAII-expressing cells in 12-week-old 3D spheroids, similar to native eccrine sweat glands, indicating that the spheroids possess a cellular structure capable of sweat secretion. We conclude that the 12-week 3D spheroids may have secretory capability. Copyright © 2017 Elsevier GmbH. All rights reserved.

A Soft, Wearable Microfluidic Device for the Capture, Storage, and Colorimetric Sensing of Sweat

PubMed Central

Koh, Ahyeon; Kang, Daeshik; Xue, Yeguang; Lee, Seungmin; Pielak, Rafal M.; Kim, Jeonghyun; Hwang, Taehwan; Min, Seunghwan; Banks, Anthony; Bastien, Philippe; Manco, Megan C.; Wang, Liang; Ammann, Kaitlyn R.; Jang, Kyung-In; Won, Phillip; Han, Seungyong; Ghaffari, Roozbeh; Paik, Ungyu; Slepian, Marvin J.; Balooch, Guive; Huang, Yonggang; Rogers, John A.

2017-01-01

Capabilities in health monitoring via capture and quantitative chemical analysis of sweat could complement, or potentially obviate the need for, approaches based on sporadic assessment of blood samples. Established sweat monitoring technologies use simple fabric swatches and are limited to basic analysis in controlled laboratory or hospital settings. We present a collection of materials and device designs for soft, flexible and stretchable microfluidic systems, including embodiments that integrate wireless communication electronics, which can intimately and robustly bond to the surface of skin without chemical and mechanical irritation. This integration defines access points for a small set of sweat glands such that perspiration spontaneously initiates routing of sweat through a microfluidic network and set of reservoirs. Embedded chemical analyses respond in colorimetric fashion to markers such as chloride and hydronium ions, glucose and lactate. Wireless interfaces to digital image capture hardware serve as a means for quantitation. Human studies demonstrated the functionality of this microfluidic device during fitness cycling in a controlled environment and during long-distance bicycle racing in arid, outdoor conditions. The results include quantitative values for sweat rate, total sweat loss, pH and concentration of both chloride and lactate. PMID:27881826

The analysis of metabolites in human sweat: analytical methods and potential application to investigation of pressure ischaemia of soft tissues.

PubMed

Taylor, R P; Polliack, A A; Bader, D L

1994-01-01

A straightforward technique was developed for sweat collection applicable to tissues subjected to external load without introducing distortion of underlying tissues, and for analysis of six metabolites in the collected sweat. Chloride was measured colorimetrically and lactate, urea and urate by enzymatic methods on a centrifugal analyser. Sodium and potassium were measured by flame photometry. The methods showed good precision, recovery and linearity. To assess the technique sweat was collected: (i) from the sacrum, ischium, forearm and calf in healthy individuals at 32 degrees C for 1 h; (ii) from the sacrum of healthy subjects at ambient temperature for 9 h; (iii) at ambient temperature from the sacrum of a patient with a history of pressure sores. Sweat rates were greater at the sacrum and ischium than the calf or forearm. There were differences in the concentrations of lactate and urea between sites but these were smaller when expressed as amount secreted. Sweat rates were significantly lower in groups (ii) and (iii), but sweat could be collected reliably. This technique has potential clinical application to the investigation of susceptibility to pressure sores.

Hot Flashes and Night Sweats (PDQ®)—Patient Version

Cancer.gov

Hot flashes and night sweats can be a side effect of cancer or its treatment and can occur in both women and men. Learn more about hot flashes and night sweats and ways to treat them in this expert-reviewed summary.

7 CFR 29.3065 - Sweating.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweating. 29.3065 Section 29.3065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [24 FR 8771, Oct. 29, 1959. Redesignated...

7 CFR 29.6042 - Sweated.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweated. 29.6042 Section 29.6042 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6042 Sweated. The condition of tobacco which has passed through one or...

7 CFR 29.6042 - Sweated.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweated. 29.6042 Section 29.6042 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6042 Sweated. The condition of tobacco which has passed through one or...

7 CFR 29.2306 - Sweated.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweated. 29.2306 Section 29.2306 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.6042 - Sweated.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweated. 29.6042 Section 29.6042 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6042 Sweated. The condition of tobacco which has passed through one or...

7 CFR 29.2307 - Sweating.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweating. 29.2307 Section 29.2307 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [37 FR 13521, July 11, 1972...

7 CFR 29.3065 - Sweating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweating. 29.3065 Section 29.3065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [24 FR 8771, Oct. 29, 1959. Redesignated...

7 CFR 29.2307 - Sweating.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweating. 29.2307 Section 29.2307 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [37 FR 13521, July 11, 1972...

7 CFR 29.3065 - Sweating.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweating. 29.3065 Section 29.3065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [24 FR 8771, Oct. 29, 1959. Redesignated...

7 CFR 29.2307 - Sweating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweating. 29.2307 Section 29.2307 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [37 FR 13521, July 11, 1972...

7 CFR 29.2307 - Sweating.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweating. 29.2307 Section 29.2307 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [37 FR 13521, July 11, 1972...

7 CFR 29.3064 - Sweated.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweated. 29.3064 Section 29.3064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.3064 - Sweated.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweated. 29.3064 Section 29.3064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.6042 - Sweated.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweated. 29.6042 Section 29.6042 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6042 Sweated. The condition of tobacco which has passed through one or...

7 CFR 29.2306 - Sweated.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweated. 29.2306 Section 29.2306 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.3065 - Sweating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweating. 29.3065 Section 29.3065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [24 FR 8771, Oct. 29, 1959. Redesignated...

7 CFR 29.2306 - Sweated.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweated. 29.2306 Section 29.2306 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.2306 - Sweated.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweated. 29.2306 Section 29.2306 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.3065 - Sweating.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweating. 29.3065 Section 29.3065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [24 FR 8771, Oct. 29, 1959. Redesignated...

7 CFR 29.3064 - Sweated.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweated. 29.3064 Section 29.3064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.2306 - Sweated.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweated. 29.2306 Section 29.2306 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.6042 - Sweated.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweated. 29.6042 Section 29.6042 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6042 Sweated. The condition of tobacco which has passed through one or...

7 CFR 29.3064 - Sweated.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweated. 29.3064 Section 29.3064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

7 CFR 29.2307 - Sweating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweating. 29.2307 Section 29.2307 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweating. The condition of tobacco in the process of fermentation. [37 FR 13521, July 11, 1972...

7 CFR 29.3064 - Sweated.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweated. 29.3064 Section 29.3064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Sweated. The condition of tobacco which has passed through one or more fermentations natural to tobacco...

Sweating

MedlinePlus Videos and Cool Tools

... half million eccrine sweat glands all over the body. They lie deep in the skin and are connected to the surface by coiled tubes called ducts. Sweat (perspiration) is a liquid mixture made up of 99% water and 1% salt and fat. Up to a quart of liquid a day ...

Imaging calcium carbonate distribution in human sweat pore in vivo using nonlinear microscopy

NASA Astrophysics Data System (ADS)

Chen, Xueqin; Gasecka, Alicja; Formanek, Florian; Galey, Jean-Baptiste; Rigneault, Hervé

2015-03-01

Nonlinear microscopies, including two-photon excited autofluorescence (TPEF) and coherent anti-Stokes Raman scattering (CARS), were used to study individual human sweat pore morphology and topically applied antiperspirant salt penetration inside sweat pore, in vivo on human palms. Sweat pore inner morphology in vivo was imaged up to the depth of 100 μm by TPEF microscopy. The 3D penetration and distribution of "in situ calcium carbonate" (isCC), an antiperspirant salt model, was investigated using CARS microscopy.

Regional differences in sweat rate response of steers to short-term heat stress

NASA Astrophysics Data System (ADS)

Scharf, B.; Wax, L. E.; Aiken, G. E.; Spiers, D. E.

2008-11-01

Six Angus steers (319 ± 8.5 kg) were assigned to one of two groups (hot or cold exposure) of three steers each, and placed into two environmental chambers initially maintained at 16.5-18.8°C air temperature ( T a). Cold chamber T a was lowered to 8.4°C, while T a within the hot chamber was increased to 32.7°C over a 24-h time period. Measurements included respiration rate, and air and body (rectal and skin) temperatures. Skin temperature was measured at shoulder and rump locations, with determination of sweat rate using a calibrated moisture sensor. Rectal temperature did not change in cold or hot chambers. However, respiration rate nearly doubled in the heat ( P < 0.05), increasing when T a was above 24°C. Skin temperatures at the two locations were highly correlated ( P < 0.05) with each other and with T a. In contrast, sweat rate showed differences at rump and shoulder sites. Sweat rate of the rump exhibited only a small increase with T a. However, sweat rate at the shoulder increased more than four-fold with increasing T a. Increased sweat rate in this region is supported by an earlier report of a higher density of sweat glands in the shoulder compared to rump regions. Sweat rate was correlated with several thermal measurements to determine the best predictor. Fourth-order polynomial expressions of short-term rectal and skin temperature responses to hot and cold exposures produced r values of 0.60, 0.84, and 0.98, respectively. These results suggest that thermal inputs other than just rectal or skin temperature drive the sweat response in cattle.

Intra-individual biological variation in sweat chloride concentrations in CF, CFTR dysfunction, and healthy pediatric subjects.

PubMed

Cirilli, Natalia; Raia, Valeria; Rocco, Ilaria; De Gregorio, Fabiola; Tosco, Antonella; Salvadori, Laura; Sepe, Angela Ornella; Buzzetti, Roberto; Minicuci, Nadia; Castaldo, Giuseppe

2018-04-02

The sweat test is one of the main diagnostic tools used in newborn screening programs and as a confirmatory test, in case of suspect of Cystic Fibrosis (CF). Since sweat chloride (Cl) concentration is also considered an appropriate parameter to explore the efficacy of CFTR modulators in clinical trials, it is crucial to evaluate the biological variability of this test in healthy and pathological conditions. The aim of this pilot study was to determine the intra-individual biological variability of sweat Cl, both in healthy individuals and CF patients and to assess its correlation with diet, season, and menstrual cycle. Thirty-five out of 36 selected subjects (6-18 years) were enrolled by 2 CF care centers and assigned to 3 cohorts: CF, CFTR-related disorder (CFTR-RD) and healthy volunteers. Each participant was subjected to eight sweat tests in different conditions and time of the year. Data were analyzed using linear mixed effects models for repeated measures, taking also into account intra-individual correlations. We observed a high intra-individual variability of sweat Cl, with the lowest mean CV% values among CF patients (20.21 in CF, 29.74 in CFTR-RD, and 31.15 in healthy subjects). Gender and diet had no influence on sweat Cl variability, nor had pubertal age and menstrual phase. Results of this pilot study confirmed that sweat Cl variability is high in CF patients, although non-CF individuals displayed even higher mean CV% values. Season significantly influenced sweat test values only in CF patients, likely due to changes in their hydration status. © 2018 Wiley Periodicals, Inc.

Effect of Sweating on Insulation of Footwear.

PubMed

Kuklane, Kalev; Holmér, Ingvar

1998-01-01

The study aimed to find out the influence of sweating on footwear insulation with a thermal foot model. Simultaneously, the influence of applied weight (35 kg), sock, and steel toe cap were studied. Water to 3 sweat glands was supplied with a pump at the rate of 10 g/hr in total. Four models of boots with steel toe caps were tested. The same models were manufactured also without steel toe. Sweating reduced footwear insulation 19-25% (30-37% in toes). During static conditions, only a minimal amount of sweat evaporated from boots. Weight affected sole insulation: Reduction depended on compressibility of sole material. The influence of steel toe varied with insulation. The method of thermal foot model appears to be a practical tool for footwear evaluation.

7 CFR 29.2558 - Sweated.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweated. 29.2558 Section 29.2558 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2558 Sweated. The condition of tobacco...

7 CFR 29.3553 - Sweated.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweated. 29.3553 Section 29.3553 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3553 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.3554 - Sweating.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweating. 29.3554 Section 29.3554 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3554 Sweating. The condition of tobacco in the process of fermentation. [30 FR 9207, July...

7 CFR 29.2558 - Sweated.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweated. 29.2558 Section 29.2558 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2558 Sweated. The condition of tobacco...

7 CFR 29.1065 - Sweating.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweating. 29.1065 Section 29.1065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1065 Sweating. The condition of tobacco in the process of fermentation. [42 FR 21092, Apr...

7 CFR 29.1065 - Sweating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweating. 29.1065 Section 29.1065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1065 Sweating. The condition of tobacco in the process of fermentation. [42 FR 21092, Apr...

7 CFR 29.2558 - Sweated.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweated. 29.2558 Section 29.2558 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2558 Sweated. The condition of tobacco...

7 CFR 29.3553 - Sweated.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweated. 29.3553 Section 29.3553 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3553 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.3554 - Sweating.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweating. 29.3554 Section 29.3554 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3554 Sweating. The condition of tobacco in the process of fermentation. [30 FR 9207, July...

7 CFR 29.1065 - Sweating.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweating. 29.1065 Section 29.1065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1065 Sweating. The condition of tobacco in the process of fermentation. [42 FR 21092, Apr...

7 CFR 29.1064 - Sweated.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweated. 29.1064 Section 29.1064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1064 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.2558 - Sweated.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweated. 29.2558 Section 29.2558 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2558 Sweated. The condition of tobacco...

7 CFR 29.2558 - Sweated.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweated. 29.2558 Section 29.2558 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2558 Sweated. The condition of tobacco...

7 CFR 29.1065 - Sweating.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweating. 29.1065 Section 29.1065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1065 Sweating. The condition of tobacco in the process of fermentation. [42 FR 21092, Apr...

7 CFR 29.3554 - Sweating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweating. 29.3554 Section 29.3554 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3554 Sweating. The condition of tobacco in the process of fermentation. [30 FR 9207, July...

7 CFR 29.1064 - Sweated.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweated. 29.1064 Section 29.1064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1064 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.1065 - Sweating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweating. 29.1065 Section 29.1065 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1065 Sweating. The condition of tobacco in the process of fermentation. [42 FR 21092, Apr...

7 CFR 29.1064 - Sweated.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweated. 29.1064 Section 29.1064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1064 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.3553 - Sweated.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweated. 29.3553 Section 29.3553 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3553 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.3553 - Sweated.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweated. 29.3553 Section 29.3553 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3553 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.1064 - Sweated.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweated. 29.1064 Section 29.1064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1064 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.3553 - Sweated.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweated. 29.3553 Section 29.3553 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3553 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.1064 - Sweated.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweated. 29.1064 Section 29.1064 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1064 Sweated. The condition of tobacco which has passed through one or more fermentations...

7 CFR 29.3554 - Sweating.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweating. 29.3554 Section 29.3554 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3554 Sweating. The condition of tobacco in the process of fermentation. [30 FR 9207, July...

7 CFR 29.3554 - Sweating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweating. 29.3554 Section 29.3554 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3554 Sweating. The condition of tobacco in the process of fermentation. [30 FR 9207, July...

Nitric oxide synthase and cyclooxygenase modulate β-adrenergic cutaneous vasodilatation and sweating in young men.

PubMed

Fujii, Naoto; McNeely, Brendan D; Kenny, Glen P

2017-02-15

β-Adrenergic receptor agonists such as isoproterenol induce cutaneous vasodilatation and sweating in humans, but the mechanisms underpinning this response remain unresolved. Using intradermal microdialysis, we evaluated the roles of nitric oxide synthase (NOS) and cyclooxygenase (COX) in β-adrenergic cutaneous vasodilatation and sweating elicited by administration of isoproterenol. We show that while NOS contributes to β-adrenergic cutaneous vasodilatation, COX restricts cutaneous vasodilatation. We also show that combined inhibition of NOS and COX augments β-adrenergic sweating These new findings advance our basic knowledge regarding the physiological control of cutaneous blood flow and sweating, and provide important and new information to better understand the physiological significance of β-adrenergic receptors in the skin. β-Adrenergic receptor agonists such as isoproterenol can induce cutaneous vasodilatation and sweating in humans, but the mechanisms underpinning this response remain unresolved. We evaluated the hypotheses that (1) nitric oxide synthase (NOS) contributes to β-adrenergic cutaneous vasodilatation, whereas cyclooxygenase (COX) limits the vasodilatation, and (2) COX contributes to β-adrenergic sweating. In 10 young males (25 ± 5 years), cutaneous vascular conductance (CVC) and sweat rate were evaluated at four intradermal forearm skin sites infused with (1) lactated Ringer solution (control), (2) 10 mm N ω -nitro-l-arginine (l-NNA), a non-specific NOS inhibitor, (3) 10 mm ketorolac, a non-specific COX inhibitor, or (4) a combination of l-NNA and ketorolac. All sites were co-administered with a high dose of isoproterenol (100 μm) for 3 min to maximally induce β-adrenergic sweating (β-adrenergic sweating is significantly blunted by subsequent activations). Approximately 60 min after the washout period, three incremental doses of isoproterenol were co-administered (1, 10 and 100 μm each for 25 min). Increases in CVC induced by the first and second 100 μm isoproterenol were attenuated by l-NNA alone, and those in response to all doses of isoproterenol were reduced by l-NNA with co-infusion of ketorolac (all P ≤ 0.05). Ketorolac alone augmented increases in CVC induced by 10 μm and by the second 100 μm isoproterenol (both P ≤ 0.05). While isoproterenol-induced sweating was not affected by the separate administration of l-NNA or ketorolac (all P > 0.05), their combined administration augmented sweating elicited by the first 3 min of 100 μm isoproterenol (P = 0.05). We show that while NOS contributes to β-adrenergic cutaneous vasodilatation, COX restrains the vasodilatation. Finally, combined inhibition of NOS and COX augments β-adrenergic sweating. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Kinetic parameters of rubidium transport pathways are normal in cystic fibrosis red cells.

PubMed

Joiner, C H

1988-10-01

The abnormalities in ion transport in cystic fibrosis (CF) respiratory and sweat duct epithelia have prompted studies of ion permeability in CF red blood cells (RBC) although previous reports have been contradictory. In this study, the kinetic characteristics of the three major cation transport systems in RBC were evaluated by measuring rubidium (Rb) uptake at various external Rb concentrations. The maximal velocity and affinity for external Rb (K1/2) of the NaK pump were normal in CF RBC, as were the maximal velocity and Km for Rb of the NaK cotransport system. Residual (ouabain and bumetanide insensitive) Rb uptake, and steady state RBC Na and K contents were also normal. These data indicate the NaK pump and cotransport system do not exhibit primary or secondary perturbations in CF RBC, and suggest that the noncarrier-mediated membrane permeability to cations is also normal in these cells.

Eccrine sweat gland development and sweat secretion.

PubMed

Cui, Chang-Yi; Schlessinger, David

2015-09-01

Eccrine sweat glands help to maintain homoeostasis, primarily by stabilizing body temperature. Derived from embryonic ectoderm, millions of eccrine glands are distributed across human skin and secrete litres of sweat per day. Their easy accessibility has facilitated the start of analyses of their development and function. Mouse genetic models find sweat gland development regulated sequentially by Wnt, Eda and Shh pathways, although precise subpathways and additional regulators require further elucidation. Mature glands have two secretory cell types, clear and dark cells, whose comparative development and functional interactions remain largely unknown. Clear cells have long been known as the major secretory cells, but recent studies suggest that dark cells are also indispensable for sweat secretion. Dark cell-specific Foxa1 expression was shown to regulate a Ca(2+) -dependent Best2 anion channel that is the candidate driver for the required ion currents. Overall, it was shown that cholinergic impulses trigger sweat secretion in mature glands through second messengers - for example InsP3 and Ca(2+) - and downstream ion channels/transporters in the framework of a Na(+) -K(+) -Cl(-) cotransporter model. Notably, the microenvironment surrounding secretory cells, including acid-base balance, was implicated to be important for proper sweat secretion, which requires further clarification. Furthermore, multiple ion channels have been shown to be expressed in clear and dark cells, but the degree to which various ion channels function redundantly or indispensably also remains to be determined. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Role of CFTR mutation analysis in the diagnostic algorithm for cystic fibrosis.

PubMed

Ratkiewicz, Michelle; Pastore, Matthew; McCoy, Karen Sharrock; Thompson, Rohan; Hayes, Don; Sheikh, Shahid Ijaz

2017-04-01

The cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation identification is being used with increased frequency to aid in the diagnosis of cystic fibrosis (CF) in those suspected with CF. Aim of this study was to identify diagnostic outcomes when CFTR mutational analysis was used in CF diagnosis. CFTR mutational analysis results were also compared with sweat chloride results. This study was done on all patients at our institution who had CFTR mutation analysis over a sevenyear period since August 2006. A total of 315 patients underwent CFTR mutational analysis. Fifty-one (16.2%) patients had two mutations identified. Among them 32 had positive sweat chloride levels (≥60 mmol/L), while seven had borderline sweat chloride levels (40-59 mmol/L). An additional 70 patients (22.3%) had only one mutation identified. Among them eight had positive sweat chloride levels, and 17 had borderline sweat chloride levels. Fifty-five patients (17.5%) without CFTR mutations had either borderline (n=45) or positive (n=10) sweat chloride results. Three patients with a CF phenotype had negative CFTR analysis but elevated sweat chloride levels. In eighty-three patients (26.4%) CFTR mutational analysis was done without corresponding sweat chloride testing. Although CFTR mutation analysis has improved the diagnostic capability for CF, its use either as the first step or the only test to diagnose CFTR dysfunction should be discouraged and CF diagnostic guidelines need to be followed.

Novel methods of imaging and analysis for the thermoregulatory sweat test.

PubMed

Carroll, Michael Sean; Reed, David W; Kuntz, Nancy L; Weese-Mayer, Debra Ellyn

2018-06-07

The thermoregulatory sweat test (TST) can be central to the identification and management of disorders affecting sudomotor function and small sensory and autonomic nerve fibers, but the cumbersome nature of the standard testing protocol has prevented its widespread adoption. A high resolution, quantitative, clean and simple assay of sweating could significantly improve identification and management of these disorders. Images from 89 clinical TSTs were analyzed retrospectively using two novel techniques. First, using the standard indicator powder, skin surface sweat distributions were determined algorithmically for each patient. Second, a fundamentally novel method using thermal imaging of forced evaporative cooling was evaluated through comparison with the standard technique. Correlation and receiver operating characteristic analyses were used to determine the degree of match between these methods, and the potential limits of thermal imaging were examined through cumulative analysis of all studied patients. Algorithmic encoding of sweating and non-sweating regions produces a more objective analysis for clinical decision making. Additionally, results from the forced cooling method correspond well with those from indicator powder imaging, with a correlation across spatial regions of -0.78 (CI: -0.84 to -0.71). The method works similarly across body regions, and frame-by-frame analysis suggests the ability to identify sweating regions within about 1 second of imaging. While algorithmic encoding can enhance the standard sweat testing protocol, thermal imaging with forced evaporative cooling can dramatically improve the TST by making it less time-consuming and more patient-friendly than the current approach.

7 CFR 29.2559 - Sweating.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 2 2012-01-01 2012-01-01 false Sweating. 29.2559 Section 29.2559 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2559 Sweating. The condition of tobacco in...

7 CFR 29.2559 - Sweating.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Sweating. 29.2559 Section 29.2559 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2559 Sweating. The condition of tobacco in...

7 CFR 29.2559 - Sweating.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Sweating. 29.2559 Section 29.2559 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2559 Sweating. The condition of tobacco in...

7 CFR 29.2559 - Sweating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Sweating. 29.2559 Section 29.2559 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2559 Sweating. The condition of tobacco in...

7 CFR 29.2559 - Sweating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Sweating. 29.2559 Section 29.2559 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2559 Sweating. The condition of tobacco in...

12 CFR 1291.5 - Competitive application program.

Code of Federal Regulations, 2014 CFR

2014-01-01

... (excluding the value of sweat equity), provided that the project's uses of funds also include or exclude... project. Cash costs do not include in-kind donations, voluntary professional labor or services, or sweat... services (excluding the value of sweat equity) committed to the project as part of the total development...

12 CFR 1291.5 - Competitive application program.

Code of Federal Regulations, 2012 CFR

2012-01-01

... (excluding the value of sweat equity), provided that the project's uses of funds also include or exclude... project. Cash costs do not include in-kind donations, voluntary professional labor or services, or sweat... services (excluding the value of sweat equity) committed to the project as part of the total development...

12 CFR 1291.5 - Competitive application program.

Code of Federal Regulations, 2011 CFR

2011-01-01

... (excluding the value of sweat equity), provided that the project's uses of funds also include or exclude... project. Cash costs do not include in-kind donations, voluntary professional labor or services, or sweat... services (excluding the value of sweat equity) committed to the project as part of the total development...

Effect of skin wettedness on sweat gland response

NASA Technical Reports Server (NTRS)

Nadel, E. R.; Stolwijk, J. A. J.

1973-01-01

Investigation of the effect of skin wettedness upon sweating rate. Several techniques were used to gain a better understanding of the quantitative nature of this effect. The results include the finding that the evaporative power of the environment has a profound effect on the relationship between body temperature and sweating rate.

12 CFR 1291.5 - Competitive application program.

Code of Federal Regulations, 2013 CFR

2013-01-01

... (excluding the value of sweat equity), provided that the project's uses of funds also include or exclude... project. Cash costs do not include in-kind donations, voluntary professional labor or services, or sweat... services (excluding the value of sweat equity) committed to the project as part of the total development...

Skin-interfaced systems for sweat collection and analytics

PubMed Central

Choi, Jungil; Ghaffari, Roozbeh; Baker, Lindsay B.; Rogers, John A.

2018-01-01

Recent interdisciplinary advances in materials, mechanics, and microsystem designs for biocompatible electronics, soft microfluidics, and electrochemical biosensors establish the foundations for emerging classes of thin, skin-interfaced platforms capable of capturing, storing, and performing quantitative, spatiotemporal measurements of sweat chemistry, instantaneous local sweat rate, and total sweat loss. This review summarizes scientific and technical progress in this area and highlights the implications in real time and ambulatory modes of deployment during physical activities across a broad range of contexts in clinical health, physiology research, fitness/wellness, and athletic performance. PMID:29487915

Wearable sweat detector device design for health monitoring and clinical diagnosis

NASA Astrophysics Data System (ADS)

Wu, Qiuchen; Zhang, Xiaodong; Tian, Bihao; Zhang, Hongyan; Yu, Yang; Wang, Ming

2017-06-01

Miniaturized sensor is necessary part for wearable detector for biomedical applications. Wearable detector device is indispensable for online health care. This paper presents a concept of an wearable digital health monitoring device design for sweat analysis. The flexible sensor is developed to quantify the amount of hydrogen ions in sweat and skin temperature in real time. The detection system includes pH sensor, temperature sensor, signal processing module, power source, microprocessor, display module and so on. The sweat monitoring device is designed for sport monitoring or clinical diagnosis.

Effect of two sweating simulation methods on clothing evaporative resistance in a so-called isothermal condition.

PubMed

Lu, Yehu; Wang, Faming; Peng, Hui

2016-07-01

The effect of sweating simulation methods on clothing evaporative resistance was investigated in a so-called isothermal condition (T manikin  = T a  = T r ). Two sweating simulation methods, namely, the pre-wetted fabric "skin" (PW) and the water supplied sweating (WS), were applied to determine clothing evaporative resistance on a "Newton" thermal manikin. Results indicated that the clothing evaporative resistance determined by the WS method was significantly lower than that measured by the PW method. In addition, the evaporative resistances measured by the two methods were correlated and exhibited a linear relationship. Validation experiments demonstrated that the empirical regression equation showed highly acceptable estimations. The study contributes to improving the accuracy of measurements of clothing evaporative resistance by means of a sweating manikin.

Sweating responses during heat acclimation and moderate conditioning

NASA Technical Reports Server (NTRS)

Shvartz, E.; Bhattacharya, A.; Sperinde, S. J.; Brock, P. J.; Sciaraffa, D.; Van Beaumont, W.

1979-01-01

Experiments were conducted on ten young male subjects to determine sweating onset, distribution, and patterns as well as the relationships of these responses to body temperature during heat acclimation and moderate conditioning performed in temperate (24 C) conditions. The subjects are randomly assigned to two groups of five subjects each. The experimental period consisted of eight successive days of either graded exercise to exhaustion on a bicycle ergometer in heat (acclimation group) or in a temperate environment (control group). Major conclusions are that (1) acclimation and conditioning result in relatively more sweat rate on the limbs than on the torso, but that these changes are less related to body temperature than torso sweat rate; and (2) sweating sensitivity increases during acclimation and conditioning, but its contribution to heat acclimation is minor.

Stretchable, wireless sensors and functional substrates for epidermal characterization of sweat.

PubMed

Huang, Xian; Liu, Yuhao; Chen, Kaile; Shin, Woo-Jung; Lu, Ching-Jui; Kong, Gil-Woo; Patnaik, Dwipayan; Lee, Sang-Heon; Cortes, Jonathan Fajardo; Rogers, John A

2014-08-13

This paper introduces materials and architectures for ultrathin, stretchable wireless sensors that mount on functional elastomeric substrates for epidermal analysis of biofluids. Measurement of the volume and chemical properties of sweat via dielectric detection and colorimetry demonstrates some capabilities. Here, inductively coupled sensors consisting of LC resonators with capacitive electrodes show systematic responses to sweat collected in microporous substrates. Interrogation occurs through external coils placed in physical proximity to the devices. The substrates allow spontaneous sweat collection through capillary forces, without the need for complex microfluidic handling systems. Furthermore, colorimetric measurement modes are possible in the same system by introducing indicator compounds into the depths of the substrates, for sensing specific components (OH(-) , H(+) , Cu(+) , and Fe(2+) ) in the sweat. The complete devices offer Young's moduli that are similar to skin, thus allowing highly effective and reliable skin integration without external fixtures. Experimental results demonstrate volumetric measurement of sweat with an accuracy of 0.06 μL/mm(2) with good stability and low drift. Colorimetric responses to pH and concentrations of various ions provide capabilities relevant to analysis of sweat. Similar materials and device designs can be used in monitoring other body fluids. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Human Elimination of Phthalate Compounds: Blood, Urine, and Sweat (BUS) Study

PubMed Central

Genuis, Stephen J.; Beesoon, Sanjay; Lobo, Rebecca A.; Birkholz, Detlef

2012-01-01

Background. Individual members of the phthalate family of chemical compounds are components of innumerable everyday consumer products, resulting in a high exposure scenario for some individuals and population groups. Multiple epidemiological studies have demonstrated statistically significant exposure-disease relationships involving phthalates and toxicological studies have shown estrogenic effects in vitro. Data is lacking in the medical literature, however, on effective means to facilitate phthalate excretion. Methods. Blood, urine, and sweat were collected from 20 individuals (10 healthy participants and 10 participants with assorted health problems) and analyzed for parent phthalate compounds as well as phthalate metabolites using high performance liquid chromatography-tandem mass spectrometry. Results. Some parent phthalates as well as their metabolites were excreted into sweat. All patients had MEHP (mono(2-ethylhexyl) phthalate) in their blood, sweat, and urine samples, suggesting widespread phthalate exposure. In several individuals, DEHP (di (2-ethylhexl) phthalate) was found in sweat but not in serum, suggesting the possibility of phthalate retention and bioaccumulation. On average, MEHP concentration in sweat was more than twice as high as urine levels. Conclusions. Induced perspiration may be useful to facilitate elimination of some potentially toxic phthalate compounds including DEHP and MEHP. Sweat analysis may be helpful in establishing the existence of accrued DEHP in the human body. PMID:23213291

A soft, wearable microfluidic device for the capture, storage, and colorimetric sensing of sweat.

PubMed

Koh, Ahyeon; Kang, Daeshik; Xue, Yeguang; Lee, Seungmin; Pielak, Rafal M; Kim, Jeonghyun; Hwang, Taehwan; Min, Seunghwan; Banks, Anthony; Bastien, Philippe; Manco, Megan C; Wang, Liang; Ammann, Kaitlyn R; Jang, Kyung-In; Won, Phillip; Han, Seungyong; Ghaffari, Roozbeh; Paik, Ungyu; Slepian, Marvin J; Balooch, Guive; Huang, Yonggang; Rogers, John A

2016-11-23

Capabilities in health monitoring enabled by capture and quantitative chemical analysis of sweat could complement, or potentially obviate the need for, approaches based on sporadic assessment of blood samples. Established sweat monitoring technologies use simple fabric swatches and are limited to basic analysis in controlled laboratory or hospital settings. We present a collection of materials and device designs for soft, flexible, and stretchable microfluidic systems, including embodiments that integrate wireless communication electronics, which can intimately and robustly bond to the surface of the skin without chemical and mechanical irritation. This integration defines access points for a small set of sweat glands such that perspiration spontaneously initiates routing of sweat through a microfluidic network and set of reservoirs. Embedded chemical analyses respond in colorimetric fashion to markers such as chloride and hydronium ions, glucose, and lactate. Wireless interfaces to digital image capture hardware serve as a means for quantitation. Human studies demonstrated the functionality of this microfluidic device during fitness cycling in a controlled environment and during long-distance bicycle racing in arid, outdoor conditions. The results include quantitative values for sweat rate, total sweat loss, pH, and concentration of chloride and lactate. Copyright © 2016, American Association for the Advancement of Science.

Revisiting sweat chloride test results based on recent guidelines for diagnosis of cystic fibrosis.

PubMed

Pagaduan, Jayson V; Ali, Mahesheema; Dowlin, Michael; Suo, Liye; Ward, Tabitha; Ruiz, Fadel; Devaraj, Sridevi

2018-03-01

Recent sweat chloride guidelines published by the Cystic Fibrosis Foundation changed the intermediate sweat chloride concentration range from 40-59 mmol/L to 30-59 mmol/L for age > 6 months. We wanted to know how this new guideline would impact detection of cystic fibrosis among patients who previously had sweat tests done at Texas Children's Hospital. We revisited sweat chloride test results (n = 3012) in the last 5 years at Texas Children's Hospital based on the new guidelines on diagnosis of cystic fibrosis from the Cystic Fibrosis Foundation. We identified 125 patients that would be reclassified in the intermediate sweat chloride value with the new guidelines that were classified as "unlikely to have CF" in the previous guidelines. 8 (32%) patients with CFTR gene testing were positive for CFTR gene mutation(s). 4 (50%) of these patients were identified to have 2 CFTR mutations. One had variant combination that was reported to cause CF but all were diagnosed with CFTR-related metabolic syndrome. Our findings concur with the new CF diagnosis guidelines that changing the intermediate cut-off to 30-59 mmol/L sweat chloride concentration in combination with CFTR genetic analysis enhances the probability of identifying individuals that have risk of developing CF or have CF and enables for earlier therapeutic intervention.

Assessment of physical demands and fluid balance in elite female handball players during a 6-day competitive tournament.

PubMed

Cunniffe, Brian; Fallan, Carissa; Yau, Adora; Evans, Gethin H; Cardinale, Marco

2015-02-01

Little data exists on drinking behavior, sweat loss, and exercise intensity across a competitive handball tournament in elite female athletes. Heart rate (HR), fluid balance and sweat electrolyte content were assessed on 17 international players across a 6-day tournament involving 5 games and 2 training sessions played indoors (23 ± 2 °C, 30 ± 2% relative humidity). Active play (effective) mean HR was 155 ± 14 bpm (80 ± 7.5% HRmax) with the majority of time (64%) spent exercising at intensities >80% HRmax. Mean (SD) sweat rates during games were 1.02 ± 0.07 L · h⁻¹ and on 56% of occasions fluid intake matched or exceeded sweat loss. A significant relationship was observed between estimated sweat loss and fluid intake during exercise (r² = .121, p = .001). Mean sweat sodium concentration was 38 ± 10 mmol · L⁻¹, with significant associations observed between player sweat rates and time spent exercising at intensities >90% HRmax (r² = .181, p = .001). Fluid and electrolyte loss appear to be work rate dependent in elite female handball players, whom appear well capable of replacing fluids lost within a tournament environment. Due to large between-athlete variations, a targeted approach may be warranted for certain players only.

Assessing the impact of egg sweating on Salmonella Enteritidis penetration into shell eggs.

PubMed

Gradl, Janet A; Curtis, Patricia A; Jones, Deana R; Anderson, Kenneth E

2017-07-01

Salmonella Enteritidis (SE) prevalence in eggs is a major concern to the egg industry. Some research has shown that egg sweating can increase Salmonella penetration into egg contents when refrigerated eggs are moved to a warmer temperature. This occurs when eggs are tempered before wash, to minimize thermal cracks. The effect of egg sweating on SE penetration into shell eggs over a 6 week storage period at 4°C was assessed. A 2 × 2 factorial of SE inoculation and egg sweating was utilized. Treatments included (SES) nalidixic acid (NA)-resistant SE inoculated and sweated, (SENS) NA-resistant SE inoculated and not sweated, (NSES) buffered peptone water (BPW) inoculated and sweated, and (NSENS) BPW inoculated and not sweated. Eggs were inoculated with 108 SE. Eggs formed condensation for approximately 17 min in a 32°C incubator. Shell rinse, shell emulsion, and egg contents were sampled then enumerated and assessed for prevalence of SE over a 6 wk storage period at 4°C. After wk 1, the SENS shell rinse had higher SE counts (0.32 log10 CFU/mL) than the other 3 treatments, where no SE was enumerated. A significant week by treatment interaction was found for the shell rinse SE detection (P < 0.05). In subsequent weeks, no SE counts were obtained from the egg shell rinse, shell emulsion, or egg contents. The SENS shell rinses had significantly higher SE prevalence than the SES rinses in weeks 1 (100% vs. 34.3%), 2 (57.6% vs. 22.2%), and 3 (38.2% vs. 11.1%) (P < 0.05). In samples from weeks 4, 5, and 6, there was no difference in SE prevalence between SES and SENS. Egg sweating did not increase SE penetration into the shell emulsion across treatment or week (P < 0.05). The decreasing trend of SE prevalence obtained over the study period indicate that refrigeration is effective at inhibiting SE growth. These results indicate that egg sweating occurring under common US egg handling practices is not harmful to egg safety. © 2017 Poultry Science Association Inc.

Qualification of a precise and easy-to-handle sweat casting imprint method for the prediction and quantification of anti-perspirant efficacy.

PubMed

Keyhani, R; Scheede, S; Thielecke, I; Wenck, H; Schmucker, R; Schreiner, V; Ennen, J; Herpens, A

2009-06-01

A time- and cost-effective sweat casting method using the forearm as test site to assess the efficacy of several anti-perspirant formulations with a low number of test subjects has been evaluated and qualified. The imprint sweat casting method is based on a 2-component silcone-imprint technique to measure the efficacy of more than eight products in parallel with the same test subject. In studies using aluminum chlorohydrate (ACH) formulations as test anti-perspirants, a clear-cut correlation could be demonstrated between sweat gland activities measured by the imprint method and gravimetric measurement of sweat gland activities. Concentration-dependent inhibition of sweat gland activity could be observed with the imprint technique up to an ACH concentration of 15%, and all formulations containing 2% ACH or above resulted in statistically significant reduction of sweat gland activity (P < 0.001) when compared with untreated control areas. Furthermore, the SDs of individual studies using the imprint technique were in a range of +/-20% of sweat gland activity, which can be regarded rather low for in vivo measurements of a complex process like sweat secretion. A group-wise comparison between the measurements of anti-perspirant activity as determined by the imprint protocol and the Food and Drug Administration (FDA) Guideline compliant gravimetric hot-room protocol revealed that the test results for anti-perspirant activity obtained with the imprint protocol are similar to those obtained with the hot-room protocol. Moreover, the data generated with the imprint protocol have a high predictive value for the outcome of a later guideline-compliant hot-room test. As the imprint casting method tends to be a little more sensitive for formulations with low anti-perspirant activity, and seems to be associated with less interassay variability than the standard gravimetric hot-room test, the imprint casting method may select products which later fail to pass the standard gravimetric hot-room test. Meanwhile the imprint sweat casting has proven to be a robust method useful to support efficacy-oriented product development. Therefore, in later stages of utilization it might even evolve into an efficient claim substantiation tool.

Skin pretreatment with microneedles prior to pilocarpine iontophoresis increases sweat production.

PubMed

Wing, David; Prausnitz, Mark R; Buono, Michael J

2013-11-01

Collection of sweat via pilocarpine iontophoresis is commonly used to diagnose cystic fibrosis (CF), with thousands of tests performed each day. The main source of resistance to the passage of pilocarpine ions to the sweat glands is the electrical resistance of the stratum corneum. It was hypothesized that pretreating the skin with 0·5 mm-long microneedles would significantly decrease this resistance, thus increasing pilocarpine's permeation into the skin. Improved permeation should result in significantly reduced time to sweat initiation, time to collection of a clinically meaningful amount of sweat, and increased total amount of sweat produced in 15 min. Subjects (n = 12) had two 5 cm(2) areas on the forearm measured, marked and randomized to experimental (microneedles + iontophoresis) or control (iontophoresis alone). Microneedle pretreatment was conducted using a 35-needle microneedle stamp in a manner that 20 applications completely covered the 5 cm(2) treatment area. This was repeated five times for a total of 100 applications. Both experimental and control sites were placed under iontophoresis (1·5 mA) for 5 min. Microneedle pretreatment significantly decreased mean skin resistance (260 ± 27 kΩ versus 160 ± 19 kΩ, P = 0·006), while significantly increasing mean sweat rate (0·76 ± 0·35 versus 0·54 ± 0·19 μl cm(2) min(-1) , P = 0·007). No significant difference was found concerning pain (P = 0·059), number of active sweat glands (P = 0·627) or the osmolality of the collected sweat (P = 0·636). The results of this study suggest that microneedle pretreatment prior to pilocarpine iontophoresis significantly increases sweat production. Such results have the potential to improve the methodology currently used to diagnose cystic fibrosis and, more broadly, to administer drugs via the skin. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

The significance of hypersensitivity to autologous sweat and serum in cholinergic urticaria: cholinergic urticaria may have different subtypes.

PubMed

Kim, Jung Eun; Jung, Kwan Ho; Cho, Hyun Hee; Kang, Hoon; Park, Young Min; Park, Hyun Jeong; Lee, Jun Young

2015-07-01

The pathogenesis of cholinergic urticaria (ChU) has been unclear except for the involvement of acetylcholine. Attempts to classify ChU according to etiology have rarely been performed. To evaluate the significance of responsiveness to autologous sweat and serum in ChU in relation to their clinical characteristics. This study involved 18 patients diagnosed with ChU between January 2010 and April 2011 in the Catholic Medical Center-St. Paul's Hospital. History taking included symptom duration, association with atopy, decreased sweat secretions, seasonal variation, and response to treatment. Intradermal autologous serum skin test (ASST) and autologous sweat skin test (ASwST) and basophil histamine release test with sweat were done. Sweat hypersensitivity was proven by a positive ASwST and basophil histamine release test in only 37.5% of patients with ChU, and in none of the healthy controls. The weal size of ASwST correlated with percentage basophil histamine release. A positive response to autologous serum was displayed by 38.9% of patients, whereas 10% of healthy controls showed a positive ASST response. Intriguingly, patients with a positive ASwST had a negative ASST, and vice versa. Despite this, there was no difference in the clinical characteristics between positive ASST and positive ASwST groups. The frequency of hypersensitivity to autologous sweat and serum was significantly higher in patients with ChU, compared with healthy controls. This suggests that autoimmunity to an unknown serum factor as well as sweat hypersensitivity may be involved in the pathogenesis of ChU. © 2014 The International Society of Dermatology.

Nitric oxide synthase and cyclooxygenase modulate β‐adrenergic cutaneous vasodilatation and sweating in young men

PubMed Central

Fujii, Naoto; McNeely, Brendan D.

2016-01-01

Key points β‐Adrenergic receptor agonists such as isoproterenol induce cutaneous vasodilatation and sweating in humans, but the mechanisms underpinning this response remain unresolved.Using intradermal microdialysis, we evaluated the roles of nitric oxide synthase (NOS) and cyclooxygenase (COX) in β‐adrenergic cutaneous vasodilatation and sweating elicited by administration of isoproterenol.We show that while NOS contributes to β‐adrenergic cutaneous vasodilatation, COX restricts cutaneous vasodilatation.We also show that combined inhibition of NOS and COX augments β‐adrenergic sweatingThese new findings advance our basic knowledge regarding the physiological control of cutaneous blood flow and sweating, and provide important and new information to better understand the physiological significance of β‐adrenergic receptors in the skin. Abstract β‐Adrenergic receptor agonists such as isoproterenol can induce cutaneous vasodilatation and sweating in humans, but the mechanisms underpinning this response remain unresolved. We evaluated the hypotheses that (1) nitric oxide synthase (NOS) contributes to β‐adrenergic cutaneous vasodilatation, whereas cyclooxygenase (COX) limits the vasodilatation, and (2) COX contributes to β‐adrenergic sweating. In 10 young males (25 ± 5 years), cutaneous vascular conductance (CVC) and sweat rate were evaluated at four intradermal forearm skin sites infused with (1) lactated Ringer solution (control), (2) 10 mm N ω‐nitro‐l‐arginine (l‐NNA), a non‐specific NOS inhibitor, (3) 10 mm ketorolac, a non‐specific COX inhibitor, or (4) a combination of l‐NNA and ketorolac. All sites were co‐administered with a high dose of isoproterenol (100 μm) for 3 min to maximally induce β‐adrenergic sweating (β‐adrenergic sweating is significantly blunted by subsequent activations). Approximately 60 min after the washout period, three incremental doses of isoproterenol were co‐administered (1, 10 and 100 μm each for 25 min). Increases in CVC induced by the first and second 100 μm isoproterenol were attenuated by l‐NNA alone, and those in response to all doses of isoproterenol were reduced by l‐NNA with co‐infusion of ketorolac (all P ≤ 0.05). Ketorolac alone augmented increases in CVC induced by 10 μm and by the second 100 μm isoproterenol (both P ≤ 0.05). While isoproterenol‐induced sweating was not affected by the separate administration of l‐NNA or ketorolac (all P > 0.05), their combined administration augmented sweating elicited by the first 3 min of 100 μm isoproterenol (P = 0.05). We show that while NOS contributes to β‐adrenergic cutaneous vasodilatation, COX restrains the vasodilatation. Finally, combined inhibition of NOS and COX augments β‐adrenergic sweating. PMID:27779753

Hydrochromic Approaches to Mapping Human Sweat Pores.

PubMed

Park, Dong-Hoon; Park, Bum Jun; Kim, Jong-Man

2016-06-21

Hydrochromic materials, which undergo changes in their light absorption and/or emission properties in response to water, have been extensively investigated as humidity sensors. Recent advances in the design of these materials have led to novel applications, including monitoring the water content of organic solvents, water-jet-based rewritable printing on paper, and hydrochromic mapping of human sweat pores. Our interest in this area has focused on the design of hydrochromic materials for human sweat pore mapping. We recognized that materials appropriate for this purpose must have balanced sensitivities to water. Specifically, while they should not undergo light absorption and/or emission transitions under ambient moisture conditions, the materials must have sufficiently high hydrochromic sensitivities that they display responses to water secreted from human sweat pores. In this Account, we describe investigations that we have carried out to develop hydrochromic substances that are suitable for human sweat pore mapping. Polydiacetylenes (PDAs) have been extensively investigated as sensor matrices because of their stimulus-responsive color change property. We found that incorporation of headgroups composed of hygroscopic ions such as cesium or rubidium and carboxylate counterions enables PDAs to undergo a blue-to-red colorimetric transition as well as a fluorescence turn-on response to water. Very intriguingly, the small quantities of water secreted from human sweat pores were found to be sufficient to trigger fluorescence turn-on responses of the hydrochromic PDAs, allowing precise mapping of human sweat pores. Since the hygroscopic ion-containing PDAs developed in the initial stage display a colorimetric transition under ambient conditions that exist during humid summer periods, a new system was designed. A PDA containing an imidazolium ion was found to be stable under all ambient conditions and showed temperature-dependent hydrochromism corresponding to a colorimetric change near body temperature. This feature enables the use of this technique to generate high-quality images of sweat pores. This Account also focuses on the results of the most recent phase of this investigation, which led to the development of a simple yet efficient and reliable technique for sweat pore mapping. The method utilizes a hydrophilic polymer composite film containing fluorescein, a commercially available dye that undergoes a fluorometric response as a result of water-dependent interconversion between its ring-closed spirolactone (nonfluorescent) and ring-opened fluorone (fluorescent) forms. Surface-modified carbon nanodots (CDs) have also been found to be efficient for hydrochromic mapping of human sweat pores. The results discovered by Lou et al. [ Adv. Mater. 2015 , 27 , 1389 ] are also included in this Account. Sweat pore maps obtained from fingertips using these materials were found to be useful for fingerprint analysis. In addition, this hydrochromism-based approach is sufficiently sensitive to enable differentiation between sweat-secreting active pores and inactive pores. As a result, the techniques can be applied to clinical diagnosis of malfunctioning sweat pores. The directions that future research in this area will follow are also discussed.

40 CFR 63.1506 - Operating requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... equipment according to the requirements in this section. (2) The owner or operator of an existing sweat furnace that meets the specifications of § 63.1505(f)(1) must operate the sweat furnace and control.... (3) The owner or operator of a new sweat furnace that meets the specifications of § 63.1505(f)(1...

24 CFR 572.130 - Restrictions on resale by initial homeowners.

Code of Federal Regulations, 2010 CFR

2010-04-01

... equity paid by the family (such as any downpayment (in the form of cash or the value of sweat equity) and... family during the family's tenure as owner (including improvements made through sweat equity), as... amounts spent on the improvements, including the cost of material and labor (or the value of the sweat...

40 CFR 63.1506 - Operating requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... equipment according to the requirements in this section. (2) The owner or operator of an existing sweat furnace that meets the specifications of § 63.1505(f)(1) must operate the sweat furnace and control.... (3) The owner or operator of a new sweat furnace that meets the specifications of § 63.1505(f)(1...

24 CFR 572.130 - Restrictions on resale by initial homeowners.

Code of Federal Regulations, 2014 CFR

2014-04-01

... equity paid by the family (such as any downpayment (in the form of cash or the value of sweat equity) and... family during the family's tenure as owner (including improvements made through sweat equity), as... amounts spent on the improvements, including the cost of material and labor (or the value of the sweat...

24 CFR 572.130 - Restrictions on resale by initial homeowners.

Code of Federal Regulations, 2013 CFR

2013-04-01

... equity paid by the family (such as any downpayment (in the form of cash or the value of sweat equity) and... family during the family's tenure as owner (including improvements made through sweat equity), as... amounts spent on the improvements, including the cost of material and labor (or the value of the sweat...

24 CFR 572.130 - Restrictions on resale by initial homeowners.

Code of Federal Regulations, 2012 CFR

2012-04-01

... equity paid by the family (such as any downpayment (in the form of cash or the value of sweat equity) and... family during the family's tenure as owner (including improvements made through sweat equity), as... amounts spent on the improvements, including the cost of material and labor (or the value of the sweat...

24 CFR 572.130 - Restrictions on resale by initial homeowners.

Code of Federal Regulations, 2011 CFR

2011-04-01

... equity paid by the family (such as any downpayment (in the form of cash or the value of sweat equity) and... family during the family's tenure as owner (including improvements made through sweat equity), as... amounts spent on the improvements, including the cost of material and labor (or the value of the sweat...

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

PubMed

L Bovell, Douglas; Kofler, Barbara; Lang, Roland

2009-01-01

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.

High follicle density does not decrease sweat gland density in Huacaya alpacas.

PubMed

Moore, K E; Maloney, S K; Blache, D

2015-01-01

When exposed to high ambient temperatures, mammals lose heat evaporatively by either sweating from glands in the skin or by respiratory panting. Like other camelids, alpacas are thought to evaporate more water by sweating than panting, despite a thick fleece, unlike sheep which mostly pant in response to heat stress. Alpacas were brought to Australia to develop an alternative fibre industry to sheep wool. In Australia, alpacas can be exposed to ambient temperatures higher than in their native South America. As a young industry there is a great deal of variation in the quality and quantity of the fleece produced in the national flock. There is selection pressure towards animals with finer and denser fleeces. Because the fibre from secondary follicles is finer than that from primary follicles, selecting for finer fibres might alter the ratio of primary and secondary follicles. In turn the selection might alter sweat gland density because the sweat glands are associated with the primary follicle. Skin biopsy and fibre samples were obtained from the mid-section of 33 Huacaya alpacas and the skin sections were processed into horizontal sections at the sebaceous gland level. Total, primary, and secondary follicles and the number of sweat gland ducts were quantified. Fibre samples from each alpaca were further analysed for mean fibre diameter. The finer-fibred animals had a higher total follicle density (P<0.001) and more sweat glands (P<0.001) than the thicker-fibred animals. The fibre diameter and total follicle density were negatively correlated (R(2)=0.56, P<0.001). Given that the finer-fibred animals had higher follicle density and more sweat glands than animals with thicker fibres, we conclude that alpacas with high follicle density should not be limited for potential sweating ability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparative Study of Efficacy and Safety of Botulinum Toxin a Injections and Subcutaneous Curettage in the Treatment of Axillary Hyperhidrosis

PubMed Central

Budamakuntla, Leelavathy; Loganathan, Eswari; George, Anju; Revanth, BN; Sankeerth, V; Sarvjnamurthy, Sacchidananda Aradhya

2017-01-01

Background: Primary focal axillary hyperhidrosis is a chronic distressing disorder affecting both the sexes. When the condition is refractory to conservative management, we should go for more promising therapies like intradermal botulinum toxin A (BtxA) injections in the axilla, and surgical therapies like subcutaneous curettage of sweat glands. Aims and Objectives: The aim of this study is to compare the efficacy, safety and duration of action of intradermal BtxA injections in one axilla and subcutaneous curettage of sweat glands in the other axilla of the same patient with axillary hyperhidrosis. Materials and Methods: Twenty patients (40 axillae) received intradermal BtxA injections on the right side (20 axillae) and underwent tumescent subcutaneous curettage of sweat glands on the left side (20 axillae). Sweat production rate was measured using gravimetry analyses at baseline and at 3 months after the procedure. Subjective analyses were done using hyperhidrosis disease severity scale (HDSS) score at baseline, at 3rd and 6th month after the procedure. Results: At 3 months post-treatment, the resting sweat rate in the toxin group improved by 80.32% versus 79.79% in the subcutaneous curettage method (P = 0.21). Exercise-induced sweat rate in the toxin group improved by 88.76% versus 88.8% in the subcutaneous curettage group (P = 0.9). There was a significant difference in the HDSS score after treatment with both the modalities. There were no adverse events with BtxA treatment compared to very minor adverse events with the surgical method. Conclusion: Both intradermal BtxA injections and tumescent subcutaneous curettage of sweat glands had a significant decrease in the sweat rates with no significant difference between the two modalities. Hence, in resource poor settings where affordability of BtxA injection is a constraint, subcutaneous curettage of sweat glands can be preferred which has been found equally effective with no or minimal adverse events. PMID:28529419

Cannabis Use Surveillance by Sweat Analysis.

PubMed

Gambelunghe, Cristiana; Fucci, Nadia; Aroni, Kyriaki; Bacci, Mauro; Marcelli, Antonio; Rossi, Riccardo

2016-10-01

Sweat testing, an alternative matrix for establishing drug abuse, offers additional benefits to the more common biological samples. The authors developed a procedure using gas chromatography-mass spectrometry to test for Δ9-tetrahydrocannabinol, 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid, cannabinol (CBN), and cannabidiol (CBD) in a sweat patch. The results were compared with urine and hair sample results. Urine, hair, and sweat samples were simultaneously collected from 12 patients who were involved, respectively, in forensic case and monitoring abuse. Selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), recovery, intraday and interday imprecision, and inaccuracy of the quantification procedure were validated. LODs in hair were 0.05 ng/mg for Δ9-tetrahydrocannabinol, CBN, and CBD, and 0.005 ng/mg for 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid. The LOD for sweat was 0.30 ng/patch for all substances. The LOQ in hair was 0.1 ng/mg for Δ9-tetrahydrocannabinol, CBN, and CBD, and 0.01 ng/mg for 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid. The LOQ was 0.4 ng/patch in sweat for each analyte. Cannabinoid in urine was determined by means of immunochemical screening (cutoff 11-nor-Δ-tetrahydrocannabinol-9-carboxylic acid 50 ng/mL). All subjects tested positive for 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid and Δ9-tetrahydrocannabinol in urine and hair. In sweat samples, Δ9-tetrahydrocannabinol was found in all patches (0.4-2.0 ng/patch); 6 cases were positive for CBN (0.4-0.5 ng/patch) and 3 for CBD (0.4-0.6 ng/patch); 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid was never detected in patches. Present sweat analysis results integrated the information from hair and urine and showed that sweat analysis is a suitable, noninvasive method for monitoring compliance with rehabilitation therapy and for detecting recent cumulative use of cannabinoids.

Sources of Variation in Sweat Chloride Measurements in Cystic Fibrosis.

PubMed

Collaco, Joseph M; Blackman, Scott M; Raraigh, Karen S; Corvol, Harriet; Rommens, Johanna M; Pace, Rhonda G; Boelle, Pierre-Yves; McGready, John; Sosnay, Patrick R; Strug, Lisa J; Knowles, Michael R; Cutting, Garry R

2016-12-01

Expanding the use of cystic fibrosis transmembrane conductance regulator (CFTR) potentiators and correctors for the treatment of cystic fibrosis (CF) requires precise and accurate biomarkers. Sweat chloride concentration provides an in vivo assessment of CFTR function, but it is unknown the degree to which CFTR mutations account for sweat chloride variation. To estimate potential sources of variation for sweat chloride measurements, including demographic factors, testing variability, recording biases, and CFTR genotype itself. A total of 2,639 sweat chloride measurements were obtained in 1,761 twins/siblings from the CF Twin-Sibling Study, French CF Modifier Gene Study, and Canadian Consortium for Genetic Studies. Variance component estimation was performed by nested mixed modeling. Across the tested CF population as a whole, CFTR gene mutations were found to be the primary determinant of sweat chloride variability (56.1% of variation) with contributions from variation over time (e.g., factors related to testing on different days; 13.8%), environmental factors (e.g., climate, family diet; 13.5%), other residual factors (e.g., test variability; 9.9%), and unique individual factors (e.g., modifier genes, unique exposures; 6.8%) (likelihood ratio test, P < 0.001). Twin analysis suggested that modifier genes did not play a significant role because the heritability estimate was negligible (H 2  = 0; 95% confidence interval, 0.0-0.35). For an individual with CF, variation in sweat chloride was primarily caused by variation over time (58.1%) with the remainder attributable to residual/random factors (41.9%). Variation in the CFTR gene is the predominant cause of sweat chloride variation; most of the non-CFTR variation is caused by testing variability and unique environmental factors. If test precision and accuracy can be improved, sweat chloride measurement could be a valuable biomarker for assessing response to therapies directed at mutant CFTR.

Sources of Variation in Sweat Chloride Measurements in Cystic Fibrosis

PubMed Central

Blackman, Scott M.; Raraigh, Karen S.; Corvol, Harriet; Rommens, Johanna M.; Pace, Rhonda G.; Boelle, Pierre-Yves; McGready, John; Sosnay, Patrick R.; Strug, Lisa J.; Knowles, Michael R.; Cutting, Garry R.

2016-01-01

Rationale: Expanding the use of cystic fibrosis transmembrane conductance regulator (CFTR) potentiators and correctors for the treatment of cystic fibrosis (CF) requires precise and accurate biomarkers. Sweat chloride concentration provides an in vivo assessment of CFTR function, but it is unknown the degree to which CFTR mutations account for sweat chloride variation. Objectives: To estimate potential sources of variation for sweat chloride measurements, including demographic factors, testing variability, recording biases, and CFTR genotype itself. Methods: A total of 2,639 sweat chloride measurements were obtained in 1,761 twins/siblings from the CF Twin-Sibling Study, French CF Modifier Gene Study, and Canadian Consortium for Genetic Studies. Variance component estimation was performed by nested mixed modeling. Measurements and Main Results: Across the tested CF population as a whole, CFTR gene mutations were found to be the primary determinant of sweat chloride variability (56.1% of variation) with contributions from variation over time (e.g., factors related to testing on different days; 13.8%), environmental factors (e.g., climate, family diet; 13.5%), other residual factors (e.g., test variability; 9.9%), and unique individual factors (e.g., modifier genes, unique exposures; 6.8%) (likelihood ratio test, P < 0.001). Twin analysis suggested that modifier genes did not play a significant role because the heritability estimate was negligible (H2 = 0; 95% confidence interval, 0.0–0.35). For an individual with CF, variation in sweat chloride was primarily caused by variation over time (58.1%) with the remainder attributable to residual/random factors (41.9%). Conclusions: Variation in the CFTR gene is the predominant cause of sweat chloride variation; most of the non-CFTR variation is caused by testing variability and unique environmental factors. If test precision and accuracy can be improved, sweat chloride measurement could be a valuable biomarker for assessing response to therapies directed at mutant CFTR. PMID:27258095

Tactile cues significantly modulate the perception of sweat-induced skin wetness independently of the level of physical skin wetness

PubMed Central

Fournet, Damien; Hodder, Simon; Havenith, George

2015-01-01

Humans sense the wetness of a wet surface through the somatosensory integration of thermal and tactile inputs generated by the interaction between skin and moisture. However, little is known on how wetness is sensed when moisture is produced via sweating. We tested the hypothesis that, in the absence of skin cooling, intermittent tactile cues, as coded by low-threshold skin mechanoreceptors, modulate the perception of sweat-induced skin wetness, independently of the level of physical wetness. Ten males (22 yr old) performed an incremental exercise protocol during two trials designed to induce the same physical skin wetness but to induce lower (TIGHT-FIT) and higher (LOOSE-FIT) wetness perception. In the TIGHT-FIT, a tight-fitting clothing ensemble limited intermittent skin-sweat-clothing tactile interactions. In the LOOSE-FIT, a loose-fitting ensemble allowed free skin-sweat-clothing interactions. Heart rate, core and skin temperature, galvanic skin conductance (GSC), and physical (wbody) and perceived skin wetness were recorded. Exercise-induced sweat production and physical wetness increased significantly [GSC: 3.1 μS, SD 0.3 to 18.8 μS, SD 1.3, P < 0.01; wbody: 0.26 no-dimension units (nd), SD 0.02, to 0.92 nd, SD 0.01, P < 0.01], with no differences between TIGHT-FIT and LOOSE-FIT (P > 0.05). However, the limited intermittent tactile inputs generated by the TIGHT-FIT ensemble reduced significantly whole-body and regional wetness perception (P < 0.01). This reduction was more pronounced when between 40 and 80% of the body was covered in sweat. We conclude that the central integration of intermittent mechanical interactions between skin, sweat, and clothing, as coded by low-threshold skin mechanoreceptors, significantly contributes to the ability to sense sweat-induced skin wetness. PMID:25878153

Pathophysiology of Hyperhidrosis.

PubMed

Schick, Christoph H

2016-11-01

Studies and case reports on excessive sweating frequently state that hyperhidrosis is a disease whose origin and mechanism are unknown. However, the term excessive is rarely based on systematic diagnostic measurements, instead being a description of the symptoms from patient histories, which suggests that hyperhidrosis is purely a problem involving the quantity of sweat, whereas it is a change in the control mechanism of sweating in which the need for and production of sweat are strongly disproportionate. This lack of proportion is perceived by those affected to be a limitation of activities of daily living and is thus pathologic. Copyright © 2016 Elsevier Inc. All rights reserved.

Chloride impermeability in cystic fibrosis

NASA Astrophysics Data System (ADS)

Quinton, Paul M.

1983-02-01

Cystic fibrosis is the most common fatal genetic disease affecting Caucasians and is perhaps best characterized as an exocrinopathy involving a disturbance in fluid and electrolyte transport1. A high NaCl concentration in the sweat is characteristic of patients with this disease; the basic physiological reason for this abnormality is unknown. We have microperfused isolated sweat ducts from control subjects and cystic fibrosis patients, and report here results which suggest that abnormally low Cl- permeability in cystic fibrosis leads to poor reabsorption of NaCl in the sweat duct, and hence to a high concentration of NaCl in the sweat.

Clear cell hidradenocarcinoma--a case report with unusual in situ malignant changes.

PubMed

Al-Irhayim, B

1984-05-01

Clear cell hidradenocarcinoma is a rare tumour, the histogenesis of which has been much debated in the past. However, it is now considered a tumour of sweat gland origin. Presented herewith is a report of a case with unusual histological features of in situ malignant changes within sweat glands. These changes very closely simulate lobular cancerisation of the breast. On reviewing the English literature on the histopathology of sweat gland tumours, we have not found similar histological findings. These histological findings provide supportive evidence of the sweat gland origin of these tumours.

Voluntary suppression of hyperthermia-induced hyperventilation mitigates the reduction in cerebral blood flow velocity during exercise in the heat.

PubMed

Tsuji, Bun; Honda, Yasushi; Ikebe, Yusuke; Fujii, Naoto; Kondo, Narihiko; Nishiyasu, Takeshi

2015-04-15

Hyperthermia during prolonged exercise leads to hyperventilation, which can reduce arterial CO2 pressure (PaCO2 ) and, in turn, cerebral blood flow (CBF) and thermoregulatory response. We investigated 1) whether humans can voluntarily suppress hyperthermic hyperventilation during prolonged exercise and 2) the effects of voluntary breathing control on PaCO2 , CBF, sweating, and skin blood flow. Twelve male subjects performed two exercise trials at 50% of peak oxygen uptake in the heat (37°C, 50% relative humidity) for up to 60 min. Throughout the exercise, subjects breathed normally (normal-breathing trial) or they tried to control their minute ventilation (respiratory frequency was timed with a metronome, and target tidal volumes were displayed on a monitor) to the level reached after 5 min of exercise (controlled-breathing trial). Plotting ventilatory and cerebrovascular responses against esophageal temperature (Tes) showed that minute ventilation increased linearly with rising Tes during normal breathing, whereas controlled breathing attenuated the increased ventilation (increase in minute ventilation from the onset of controlled breathing: 7.4 vs. 1.6 l/min at +1.1°C Tes; P < 0.001). Normal breathing led to decreases in estimated PaCO2 and middle cerebral artery blood flow velocity (MCAV) with rising Tes, but controlled breathing attenuated those reductions (estimated PaCO2 -3.4 vs. -0.8 mmHg; MCAV -10.4 vs. -3.9 cm/s at +1.1°C Tes; P = 0.002 and 0.011, respectively). Controlled breathing had no significant effect on chest sweating or forearm vascular conductance (P = 0.67 and 0.91, respectively). Our results indicate that humans can voluntarily suppress hyperthermic hyperventilation during prolonged exercise, and this suppression mitigates changes in PaCO2 and CBF. Copyright © 2015 the American Physiological Society.

Voluntary suppression of hyperthermia-induced hyperventilation mitigates the reduction in cerebral blood flow velocity during exercise in the heat

PubMed Central

Tsuji, Bun; Honda, Yasushi; Ikebe, Yusuke; Fujii, Naoto; Kondo, Narihiko

2015-01-01

Hyperthermia during prolonged exercise leads to hyperventilation, which can reduce arterial CO2 pressure (PaCO2) and, in turn, cerebral blood flow (CBF) and thermoregulatory response. We investigated 1) whether humans can voluntarily suppress hyperthermic hyperventilation during prolonged exercise and 2) the effects of voluntary breathing control on PaCO2, CBF, sweating, and skin blood flow. Twelve male subjects performed two exercise trials at 50% of peak oxygen uptake in the heat (37°C, 50% relative humidity) for up to 60 min. Throughout the exercise, subjects breathed normally (normal-breathing trial) or they tried to control their minute ventilation (respiratory frequency was timed with a metronome, and target tidal volumes were displayed on a monitor) to the level reached after 5 min of exercise (controlled-breathing trial). Plotting ventilatory and cerebrovascular responses against esophageal temperature (Tes) showed that minute ventilation increased linearly with rising Tes during normal breathing, whereas controlled breathing attenuated the increased ventilation (increase in minute ventilation from the onset of controlled breathing: 7.4 vs. 1.6 l/min at +1.1°C Tes; P < 0.001). Normal breathing led to decreases in estimated PaCO2 and middle cerebral artery blood flow velocity (MCAV) with rising Tes, but controlled breathing attenuated those reductions (estimated PaCO2 −3.4 vs. −0.8 mmHg; MCAV −10.4 vs. −3.9 cm/s at +1.1°C Tes; P = 0.002 and 0.011, respectively). Controlled breathing had no significant effect on chest sweating or forearm vascular conductance (P = 0.67 and 0.91, respectively). Our results indicate that humans can voluntarily suppress hyperthermic hyperventilation during prolonged exercise, and this suppression mitigates changes in PaCO2 and CBF. PMID:25632021

Wearable Sweat Rate Sensors for Human Thermal Comfort Monitoring.

PubMed

Sim, Jai Kyoung; Yoon, Sunghyun; Cho, Young-Ho

2018-01-19

We propose watch-type sweat rate sensors capable of automatic natural ventilation by integrating miniaturized thermo-pneumatic actuators, and experimentally verify their performances and applicability. Previous sensors using natural ventilation require manual ventilation process or high-power bulky thermo-pneumatic actuators to lift sweat rate detection chambers above skin for continuous measurement. The proposed watch-type sweat rate sensors reduce operation power by minimizing expansion fluid volume to 0.4 ml through heat circuit modeling. The proposed sensors reduce operation power to 12.8% and weight to 47.6% compared to previous portable sensors, operating for 4 hours at 6 V batteries. Human experiment for thermal comfort monitoring is performed by using the proposed sensors having sensitivity of 0.039 (pF/s)/(g/m 2 h) and linearity of 97.9% in human sweat rate range. Average sweat rate difference for each thermal status measured in three subjects shows (32.06 ± 27.19) g/m 2 h in thermal statuses including 'comfortable', 'slightly warm', 'warm', and 'hot'. The proposed sensors thereby can discriminate and compare four stages of thermal status. Sweat rate measurement error of the proposed sensors is less than 10% under air velocity of 1.5 m/s corresponding to human walking speed. The proposed sensors are applicable for wearable and portable use, having potentials for daily thermal comfort monitoring applications.

Correlation of sweat chloride and percent predicted FEV1 in cystic fibrosis patients treated with ivacaftor.

PubMed

Fidler, Meredith C; Beusmans, Jack; Panorchan, Paul; Van Goor, Fredrick

2017-01-01

Ivacaftor, a CFTR potentiator that enhances chloride transport by acting directly on CFTR to increase its channel gating activity, has been evaluated in patients with different CFTR mutations. Several previous analyses have reported no statistical correlation between change from baseline in ppFEV 1 and reduction in sweat chloride levels for individuals treated with ivacaftor. The objective of the post hoc analysis described here was to expand upon previous analyses and evaluate the correlation between sweat chloride levels and absolute ppFEV 1 changes across multiple cohorts of patients with different CF-causing mutations who were treated with ivacaftor. The goal of the analysis was to help define the potential value of sweat chloride as a pharmacodynamic biomarker for use in CFTR modulator trials. For any given study, reductions in sweat chloride levels and improvements in absolute ppFEV 1 were not correlated for individual patients. However, when the data from all studies were combined, a statistically significant correlation between sweat chloride levels and ppFEV 1 changes was observed (p<0.0001). Thus, sweat chloride level changes in response to potentiation of the CFTR protein by ivacaftor appear to be a predictive pharmacodynamic biomarker of lung function changes on a population basis but are unsuitable for the prediction of treatment benefits for individuals. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Estimation of sweat rates during cycling exercise by means of the closed chamber condenser technology.

PubMed

Clarys, P; Clijsen, R; Barel, A O; Schouteden, R; van Olst, B; Aerenhouts, D

2017-02-01

Knowledge of local sweating patterns is of importance in occupational and exercise physiology settings. The recently developed closed chamber condenser technology (Biox Aquaflux ® ) allows the measurement of evaporative skin water loss with a greater measurement capacity (up to 1325 g/h/m 2 ) compared to traditional evaporimeters. The aim of this study was to evaluate the applicability of the Biox Aquaflux ® to estimate sweat production during exercise. Fourteen healthy subjects performed a 20-min cycle ergometer trial at respectively 55% heart rate (HR reserve and 75% HR reserve . Sweat production was estimated by measuring body weight before and after exercise, by calculating the amount of sweat collected in a patch, and by measuring the water flux (in g/h/m 2 ) with the Biox Aquaflux ® instrument. The Biox Aquaflux ® instrument allowed the follow up of sweat kinetics at both intensities. Correlations between the measurement methods were all significant for the 75% HR reserve trial (with r ranging from 0.68 to 0.76) whilst for the 55% HR reserve a significant relation was detected between the patch method and the Biox Aquaflux ® only (with r ranging from 0.41 to 0.79). The Biox Aquaflux ® instrument is a practical and direct method for the estimation of local sweat rates under field conditions. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Optimization study for metabolomics analysis of human sweat by liquid chromatography-tandem mass spectrometry in high resolution mode.

PubMed

Calderón-Santiago, M; Priego-Capote, F; Jurado-Gámez, B; Luque de Castro, M D

2014-03-14

Sweat has recently gained popularity as a potential tool for diagnostics and biomarker monitoring as it is a non-invasive biofluid the composition of which could be modified by certain pathologies, as is the case with cystic fibrosis, which increases chloride levels in sweat. The aim of the present study was to develop an analytical method for analysis of human sweat by liquid chromatography-mass spectrometry (LC-Q-TOF MS/MS) in high resolution mode. Thus, different sample preparation strategies and different chromatographic modes (HILIC and C18 reverse modes) were compared to check their effect on the profile of sweat metabolites. Forty-one compounds were identified by the MS/MS information obtained with a mass tolerance window below 4 ppm. Amino acids, dicarboxylic acids and other interesting metabolites such as inosine, choline, uric acid and tyramine were identified. Among the tested protocols, direct analysis after dilution was a suited option to obtain a representative snapshot of sweat metabolome. In addition, sample clean up by C18 SpinColumn SPE cartridges improved the sensitivity of most identified compounds and reduced the number of interferents. As most of the identified metabolites are involved in key biochemical pathways, this study opens new possibilities to the use of sweat as a source of metabolite biomarkers of specific disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

Noninvasive monitoring of plasma L-dopa concentrations using sweat samples in Parkinson's disease.

PubMed

Tsunoda, Makoto; Hirayama, Masaaki; Tsuda, Takao; Ohno, Kinji

2015-03-10

L-dopa (l-3,4-dihydroxyphenylalanine) is commonly used for treating Parkinson's disease (PD). However, regardless of its prominent effect, therapeutic range of L-dopa narrows down with disease progression, which leads to development of motor complications including wearing off and dyskinesias. In addition, intestinal absorption of L-dopa is inversely correlated with the amount of oral protein intake, and shows intra- and inter-day variability. Hence, frequent monitoring of plasma L-dopa concentrations is beneficial, but frequent venipuncture imposes physical and psychological burdens on patients with PD. We investigated the usefulness of sweat samples instead of plasma samples for monitoring L-dopa concentrations. With a monolithic silica disk-packed spin column and the high-performance liquid chromatography-electrochemical detection system, L-dopa in sweat samples was successfully quantified and analyzed in 23 PD patients. We found that the Pearson's correlation coefficient of the plasma and sweat l-dopa concentrations was 0.678. Although the disease durations and severities were not correlated with the deviation of the actual sweat L-dopa concentrations from the fitted line, acquisition of the sweat samples under a stable condition was technically difficult in severely affected patients. The deviations may also be partly accounted for by skin permeability of L-dopa. Measuring L-dopa concentrations in sweat is suitable to get further insights into the L-dopa metabolism. Copyright © 2015 Elsevier B.V. All rights reserved.

Wearable/disposable sweat-based glucose monitoring device with multistage transdermal drug delivery module

PubMed Central

Lee, Hyunjae; Song, Changyeong; Hong, Yong Seok; Kim, Min Sung; Cho, Hye Rim; Kang, Taegyu; Shin, Kwangsoo; Choi, Seung Hong; Hyeon, Taeghwan; Kim, Dae-Hyeong

2017-01-01

Electrochemical analysis of sweat using soft bioelectronics on human skin provides a new route for noninvasive glucose monitoring without painful blood collection. However, sweat-based glucose sensing still faces many challenges, such as difficulty in sweat collection, activity variation of glucose oxidase due to lactic acid secretion and ambient temperature changes, and delamination of the enzyme when exposed to mechanical friction and skin deformation. Precise point-of-care therapy in response to the measured glucose levels is still very challenging. We present a wearable/disposable sweat-based glucose monitoring device integrated with a feedback transdermal drug delivery module. Careful multilayer patch design and miniaturization of sensors increase the efficiency of the sweat collection and sensing process. Multimodal glucose sensing, as well as its real-time correction based on pH, temperature, and humidity measurements, maximizes the accuracy of the sensing. The minimal layout design of the same sensors also enables a strip-type disposable device. Drugs for the feedback transdermal therapy are loaded on two different temperature-responsive phase change nanoparticles. These nanoparticles are embedded in hyaluronic acid hydrogel microneedles, which are additionally coated with phase change materials. This enables multistage, spatially patterned, and precisely controlled drug release in response to the patient’s glucose level. The system provides a novel closed-loop solution for the noninvasive sweat-based management of diabetes mellitus. PMID:28345030

Thermoregulatory defense mechanisms.

PubMed

Sessler, Daniel I

2009-07-01

Core body temperature is normally tightly regulated by an effective thermoregulatory system. Thermoregulatory control is sometimes impaired by serious illness, but more typically remains intact. The primary autonomic defenses against heat are sweating and active precapillary vasodilation; the primary autonomic defenses against cold are arteriovenous shunt vasoconstriction and shivering. The core temperature triggering each response defines its activation threshold. Temperatures between the sweating and vasoconstriction thresholds define the inter-threshold range. The shivering threshold is usually a full 1 degrees C below the vasoconstriction threshold and is therefore a "last resort" response. Both vasoconstriction and shivering are associated with autonomic and hemodynamic activation; and each response is effective, thus impeding induction of therapeutic hypothermia. It is thus helpful to accompany core cooling with drugs that pharmacologically induce a degree of thermal tolerance. No perfect drug or drug combination has been identified. Anesthetics, for example, induce considerable tolerance, but are rarely suitable. Meperidine-especially in combination with buspirone-is especially effective while provoking only modest toxicity. The combination of buspirone and dexmedetomidine is comparably effective while avoiding the respiratory depression association with opioid administration.

76 FR 67759 - Announcement of Funding Awards for the Self-Help Homeownership Opportunity Program (SHOP) for...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-02

... contribute a minimum of 100 hours of sweat equity on the construction of their homes and/or the homes of other homebuyers participating in the local self-help housing program. Sweat equity can include, but is... required. The SHOP funds together with the sweat equity and volunteer labor contributions significantly...

75 FR 62849 - Announcement of Funding Awards for the Self-Help Homeownership Opportunity Program (SHOP) for...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-13

... homebuyers contribute a minimum of 100 hours of sweat equity on the construction of their homes and/or the homes of other homebuyers participating in the local self-help housing program. Sweat equity can include... labor is also required. The SHOP funds together with the sweat equity and volunteer labor contributions...

76 FR 48876 - Announcement of Funding Awards for the Self-Help Homeownership Opportunity Program (SHOP) for...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-09

... homebuyers contribute a minimum of 100 hours of sweat equity on the construction of their homes and/or the homes of other homebuyers participating in the local self-help housing program. Sweat equity can include... labor is also required. The SHOP funds together with the sweat equity and volunteer labor contributions...

Sweating Like a Pig: Physics or Irony?

ERIC Educational Resources Information Center

Bohren, Craig F.

2016-01-01

In his interesting and informative book "Is That a Fact?," Joe Schwarcz avers that pigs do not sweat and the saying "sweating like a pig" originates in iron smelting. Oblong pieces of hot iron, with a fancied resemblance to a sow with piglets, cool in sand to the dew point of the surrounding air, and hence water condenses on…

Comparative analysis of T2 selective division of rami-communicantes (ramicotomy) with T2 sympathetic clipping in the treatment of craniofacial hyperhidrosis.

PubMed

Kim, Do Hyung; Paik, Hyo Chae; Lee, Doo Yun

2004-08-01

The main cause of dissatisfaction after sympathetic trunk blocking surgery (T2 sympathectomy, sympathetic clipping) for craniofacial hyperhidrosis is compensatory sweating. Preserving sympathetic trunk may decrease the incidence of compensatory sweating, and we introduce T2 ramicotomy, which may better preserve the sympathetic nerve trunk in order to reduce compensatory sweating. From January 2000 to November 2002, video-assisted thoracoscopic (VAT) T2 sympathetic clipping and VAT ramicotomy were performed in 44 patients suffering from craniofacial hyperhidrosis. Twenty-two patients underwent T2 sympathetic clipping (group 1), and 22 underwent division of T2 rami-communicantes (group 2). We retrospectively analyzed the rate of satisfaction, dryness of face, and grade of compensatory sweating. Both groups were similar with respect to facial dryness (P = 0.099). Group 1: excessive dry 5 patients (22.7%), dry 17 patients (77.3%); group 2: excessive dry 3 patients (13.6%), dry 15 patients (68.1%), and persistent sweating 4 patients (18.3%). The rate of satisfaction was 77.3% in group 1, and 63.6% in group 2 with no significant difference (P > 0.05). The rate of compensatory sweating in group 2 (72.7%) was significantly lower than in group 1 (95.4%) (P < 0.039). The chance of embarrassing and disabling compensatory sweating was lower in group 2 than in group 1; 76.5% (embarrassing in 8 patients, disabling in 9) in group 1, and 36.4% (embarrassing in 7 patients, disabling in 1) in group 2 which was statistically significant (P < 0.006). T2 ramicotomy for craniofacial hyperhidrosis lowers the rate of compensatory sweating and excessive dryness of face compared to T2 clipping.

Variability of measurements of sweat sodium using the regional absorbent-patch method.

PubMed

Dziedzic, Christine E; Ross, Megan L; Slater, Gary J; Burke, Louise M

2014-09-01

There is interest in including recommendations for the replacement of the sodium lost in sweat in individualized hydration plans for athletes. Although the regional absorbent-patch method provides a practical approach to measuring sweat sodium losses in field conditions, there is a need to understand the variability of estimates associated with this technique. Sweat samples were collected from the forearms, chest, scapula, and thigh of 12 cyclists during 2 standardized cycling time trials in the heat and 2 in temperate conditions. Single measure analysis of sodium concentration was conducted immediately by ion-selective electrodes (ISE). A subset of 30 samples was frozen for reanalysis of sodium concentration using ISE, flame photometry (FP), and conductivity (SC). Sweat samples collected in hot conditions produced higher sweat sodium concentrations than those from the temperate environment (P = .0032). A significant difference (P = .0048) in estimates of sweat sodium concentration was evident when calculated from the forearm average (mean ± 95% CL; 64 ± 12 mmol/L) compared with using a 4-site equation (70 ± 12 mmol/L). There was a high correlation between the values produced using different analytical techniques (r2 = .95), but mean values were different between treatments (frozen FP, frozen SC > immediate ISE > frozen ISE; P < .0001). Whole-body sweat sodium concentration estimates differed depending on the number of sites included in the calculation. Environmental testing conditions should be considered in the interpretation of results. The impact of sample freezing and subsequent analytical technique was small but statistically significant. Nevertheless, when undertaken using a standardized protocol, the regional absorbent-patch method appears to be a relatively robust field test.

Long-term outcomes of children with intermediate sweat chloride values in infancy.

PubMed

Groves, Tyler; Robinson, Paul; Wiley, Veronica; Fitzgerald, Dominic A

2015-06-01

To describe the clinical course of children who have intermediate sweat chloride values on initial screening for cystic fibrosis (CF). We performed a retrospective review of children with intermediate sweat chloride values (raised immunoreactive trypsinogen/1 copy of p.F508del CF mutation on newborn screening (NBS)/sweat chloride value of 30-59 mmol/L) presenting to The Children's Hospital at Westmead over 15 years. Patients with an intermediate sweat chloride evolving to a formal diagnosis of CF (termed "delayed CF") were matched (2:1) with NBS positive patients with CF (termed "NBS positive CF"). Clinical outcomes were compared. Fourteen of 29 (48%, 95% CI 0.3-0.66) patients with intermediate sweat chloride value evolved to a diagnosis of CF and were matched with 28 NBS positive patients with CF. Delayed CF had less pancreatic insufficiency (OR 0.06, 95% CI 0.01-0.44, P = .006), less colonization with nonmucoid Pseudomonas aeruginosa (OR 0.04, 95% CI 0.01-0.38, P = .005), milder obstructive lung disease (forced expiratory volume in 1 second/forced vital capacity ratio), and overall disease severity (Shwachman scores) at 10 years (mean difference 5.93, 95% CI 0.39-11.46, P = .04; mean difference 4.72, 95% CI 0.9-8.53, P = .015, respectively). Nutritional outcomes were better at 2 years for delayed CF but did not persist to later ages. In this cohort, approximately one-half of infants with intermediate sweat chloride value were later diagnosed with CF. The clinical course of delayed CF was milder in some aspects compared with NBS positive CF. These results emphasize the importance of ongoing follow-up of infants with intermediate sweat chloride values. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Maximal Oxygen Uptake, Sweating and Tolerance to Exercise in the Heat

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Castle, B. L.; Ruff, W. K.

1972-01-01

The physiological mechanisms that facilitate acute acclimation to heat have not been fully elucidated, but the result is the establishment of a more efficient cardiovascular system to increase heat dissipation via increased sweating that allows the acclimated man to function with a cooler internal environment and to extend his performance. Men in good physical condition with high maximal oxygen uptakes generally acclimate to heat more rapidly and retain it longer than men in poorer condition. Also, upon first exposure trained men tolerate exercise in the heat better than untrained men. Both resting in heat and physical training in a cool environment confer only partial acclimation when first exposed to work in the heat. These observations suggest separate additive stimuli of metabolic heat from exercise and environmental heat to increase sweating during the acclimation process. However, the necessity of utilizing physical exercise during acclimation has been questioned. Bradbury et al. (1964) have concluded exercise has no effect on the course of heat acclimation since increased sweating can be induced by merely heating resting subjects. Preliminary evidence suggests there is a direct relationship between the maximal oxygen uptake and the capacity to maintain thermal regulation, particularly through the control of sweating. Since increased sweating is an important mechanism for the development of heat acclimation, and fit men have high sweat rates, it follows that upon initial exposure to exercise in the heat, men with high maximal oxygen uptakes should exhibit less strain than men with lower maximal oxygen uptakes. The purpose of this study was: (1) to determine if men with higher maximal oxygen uptakes exhibit greater tolerance than men with lower oxygen uptakes during early exposure to exercise in the heat, and (2) to investigate further the mechanism of the relationship between sweating and maximal work capacity.

Is sweat chloride predictive of severity of cystic fibrosis lung disease assessed by chest computed tomography?

PubMed

Caudri, Daan; Zitter, David; Bronsveld, Inez; Tiddens, Harm

2017-09-01

Cystic Fibrosis (CF) lung disease is characterized by a marked heterogeneity. Sweat chloride-level is a functional marker of the CF Transmembrane Regulator (CFTR) protein and could be an important predictor of later disease severity. In this retrospective analysis children from the Rotterdam CF clinic with available sweat chloride level at diagnosis and at least one routine spirometry-controlled volumetric chest CT scan in follow-up were included. CT scans were scored using the CF-CT scoring system (% of maximum). Associations between sweat chloride-levels and CF-CT scores were calculated using linear regression models, adjusting for age at sweat test and age at follow-up. Because structural lung damage develops over the course of many years, effect modification by the age at follow-up CT-scan was tested for by age-stratification. In 59 children (30 male) sweat chloride was measured at diagnosis (median age 0.5 years, range 0-13) and later chest CT performed (median age 14 years, range 6-18). Sweat chloride was associated with significantly higher CT-CT total score, bronchiectasis score, and mucus plugging score. Stratification for age at follow-up in tertiles showed this association remained only in the oldest age group (range 15-18 years). In that subgroup associations were found with all but one of the CF-CT subscores, as well as with all tested lung functions parameters. Sweat chloride-level is a significant predictor of CF lung disease severity as determined by chest CT and lung function. This association could only be demonstrated in children with follow-up to age 15 years and above. © 2017 Wiley Periodicals, Inc.

Behavioral response of the malaria mosquito, Anopheles gambiae, to human sweat inoculated with axilla bacteria and to volatiles composing human axillary odor.

PubMed

Frei, Jérôme; Kröber, Thomas; Troccaz, Myriam; Starkenmann, Christian; Guerin, Patrick M

2017-02-01

The responses of Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) to odors from male and female axillary sweat incubated with human axilla bacteria were recorded in a dual-choice olfactometer. Staphylococcus epidermidis was selected for its low odor-producing pattern, Corynebacterium jeikeium for its strong Nα-acylglutamine aminoacylase activity liberating carboxylic acids including (R)/(S)-3-hydroxy-3-methylhexanoic acid (HMHA) and Staphylococcus haemolyticus for its capacity to liberate sulfur-containing compounds including (R/S)-3-methyl-3-sulfanylhexan-1-ol (MSH). Anopheles gambiae behavioral responses were evaluated under (i) its responsiveness to take off and undertake sustained upwind flight and (ii) its discriminating capacity between the two olfactometer arms bearing a test odor in either one or both arms. Experiments were conducted in the presence of carbon dioxide pulses as a behavioral sensitizer. Anopheles gambiae clearly discriminated for the olfactometer arm conveying odor generated by incubating any of the three bacteria species with either male or female sweat. Whereas An. gambiae did not discriminate between male and female sterile sweat samples in the olfactometer, the mosquito consistently showed a preference for male sweat over female sweat incubated with the same bacterium, independent of the species used as inoculum. Sweat incubated with C. jeikeium rendered mosquitoes particularly responsive and this substrate elicited the strongest preference for male over female sweat. Tested on their own, neither HMHA nor MSH elicited a clear discriminating response but did affect mosquito responsiveness. These findings serve as a basis for further research on the odor-mediated anthropophilic host-seeking behavior of An. gambiae. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Normative data on regional sweat-sodium concentrations of professional male team-sport athletes.

PubMed

Ranchordas, Mayur K; Tiller, Nicholas B; Ramchandani, Girish; Jutley, Raj; Blow, Andrew; Tye, Jonny; Drury, Ben

2017-01-01

The purpose of this paper was to report normative data on regional sweat sweat-sodium concentrations of various professional male team-sport athletes, and to compare sweat-sodium concentrations among sports. Data to this effect would inform our understanding of athlete sodium requirements, thus allowing for the individualisation of sodium replacement strategies. Accordingly, data from 696 athletes (Soccer, n = 270; Rugby, n = 181; Baseball, n = 133; American Football, n = 60; Basketball, n = 52) were compiled for a retrospective analysis. Regional sweat-sodium concentrations were collected using the pilocarpine iontophoresis method, and compared to self-reported measures collected via questionnaire. Sweat-sodium concentrations were significantly higher ( p < 0.05) in American football (50.4 ± 15.3 mmol·L -1 ), baseball (54.0 ± 14.0 mmol·L -1 ), and basketball (48.3 ± 14.0 mmol·L -1 ) than either soccer (43.2 ± 12.0 mmol·L -1 ) or rugby (44.0 ± 12.1 mmol·L -1 ), but with no differences among the N.American or British sports. There were strong positive correlations between sweat-sodium concentrations and self-reported sodium losses in American football ( r s = 0.962, p < 0.001), basketball ( r s = 0.953, p < 0.001), rugby ( r s = 0.813, p < 0.001), and soccer ( r s = 0.748, p < 0.001). The normative data provided on sweat-sodium concentrations might assist sports science/medicine practitioners in generating bespoke hydration and electrolyte-replacement strategies to meet the sodium demands of professional team-sport athletes. Moreover, these novel data suggest that self-reported measures of sodium loss might serve as an effective surrogate in the absence of direct measures; i.e., those which are more expensive or non-readily available.

Methylxanthine Drug Monitoring with Wearable Sweat Sensors.

PubMed

Tai, Li-Chia; Gao, Wei; Chao, Minghan; Bariya, Mallika; Ngo, Quynh P; Shahpar, Ziba; Nyein, Hnin Y Y; Park, Hyejin; Sun, Junfeng; Jung, Younsu; Wu, Eric; Fahad, Hossain M; Lien, Der-Hsien; Ota, Hiroki; Cho, Gyoujin; Javey, Ali

2018-06-01

Drug monitoring plays crucial roles in doping control and precision medicine. It helps physicians tailor drug dosage for optimal benefits, track patients' compliance to prescriptions, and understand the complex pharmacokinetics of drugs. Conventional drug tests rely on invasive blood draws. While urine and sweat are attractive alternative biofluids, the state-of-the-art methods require separate sample collection and processing steps and fail to provide real-time information. Here, a wearable platform equipped with an electrochemical differential pulse voltammetry sensing module for drug monitoring is presented. A methylxanthine drug, caffeine, is selected to demonstrate the platform's functionalities. Sweat caffeine levels are monitored under various conditions, such as drug doses and measurement time after drug intake. Elevated sweat caffeine levels upon increasing dosage and confirmable caffeine physiological trends are observed. This work leverages a wearable sweat sensing platform toward noninvasive and continuous point-of-care drug monitoring and management. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantification of sweat gland volume and innervation in neuropathy: Correlation with thermoregulatory sweat testing.

PubMed

Loavenbruck, Adam; Wendelschaefer-Crabbe, Gwen; Sandroni, Paola; Kennedy, William R

2014-10-01

No study has correlated thermoregulatory sweat testing (TST) with histopathologic study of sweat glands (SGs) and SG nerve fibers (SGNFs). We studied 10 neuropathy patients in whom anhidrosis was found by TST and 10 matched controls. Skin biopsies were taken from both anhidrotic and sweating skin and immunohistochemical staining was done for nerves and basement membrane. For each biopsy, total tissue volume, total SG volume, and total SGNF length were measured. SGNF length per biopsy volume, SG volume per biopsy volume (SG%), and SGNF length per SG volume were calculated. SGNF length per biopsy volume was reduced in anhidrotic site biopsies of patients compared with controls. SG% was decreased and SGNF length per SG volume increased in patients compared with controls. The results suggest a concomitant loss of SG volume and SGNF length in neuropathy, with greater loss of SGNFs in anhidrotic skin, possibly exceeding collateral reinnervation. Copyright © 2014 Wiley Periodicals, Inc.

Thermoregulatory effects of caffeine ingestion during rest and exercise in men

NASA Technical Reports Server (NTRS)

Dunagan, Nancy; Greenleaf, John E.; Cisar, Craig J.

1994-01-01

Body temperatures and thermoregulatory responses were measured at rest and during submaximal exercise under normal ambient conditions in 11 aerobically-conditioned men (age = 29.2 +/- 6.2 yr, VO2(max) = 3.73 +/- 0.46 min(sup -1), relative body fat = 12.3 +/- 3.7 percent, mean +/- SD) with (CT) and without (NCT) the ingestion of 10 mg of caffeine per kg of body weight. Oxygen uptake (VO2), heart rate (HR), and rectal (T(sub re)) and mean skin (T-bar(sub sk)) temperatures were recorded for 100 minutes starting one minute after ingestion of caffeine or a placebo. Data were collected throughout 30 minutes of rest (sitting) and the following 70 minutes of sitting leg ergometer exercise using the same constant load (1,088 +/- 153 kgm/min) in both NCT and CT. The load resulted in a mean relative exercise intensity equal to approximately 68 percent of VO2(sub max). Skin heat conductance (H(sub sk)) and sweat rate were calculated. Two-way analysis of covariance revealed no significant (P greater than 0.05) differences between NCT and CT in VO2, HR, T(sub re), T-bar(sub sk), or H(sub sk). A dependent t-test indicated no significant difference between NCT and CT in sweat rate. Thus, a high level of caffeine ingestion has no detrimental effects on body temperatures and thermoregulatory responses during moderately heavy exercise in normal ambient conditions.

210Po secretion from sweat glands.

PubMed

Romańczyk, Grzegorz; Boryło, Alicja

2017-02-01

The results of the research indicated that the 210 Po activity concentration in sweat samples was between 0.22 ± 0.03 to 2.10 ± 0.15 mBq·g -1 d.w. The obtained results of the studies showed that smoking and eating fish led to higher activity concentrations of 210 Po in sweat in comparison to the control group. Statistical analysis of 210 Po activity concentrations in sweat samples showed significant differences between control, smoking, fish eating and age groups, while no significant differences was found for 210 Po between volunteers as far as gender is concerned. Copyright © 2016. Published by Elsevier Ltd.

Effect of antiperspirants on whole body sweat rate and thermoregulation.

PubMed

Burry, J S; Evans, R L; Rawlings, A V; Shiu, J

2003-08-01

It is well established that the evaporation of sweat from the human body surface is the main mechanism by which heat balance is maintained following a rise in body core temperature. Since the introduction of the first brand name antiperspirant in the United States during the early 1900s, antiperspirant products designed to control underarm wetness have grown to represent one of the largest cosmetic categories in most global markets. However, although axillary sweating only constitutes less than 1% of whole body sweat rate, consumers, particularly in hot countries, have begun to articulate the concern that antiperspirants may interfere with the body's natural cooling process. To investigate this, we undertook carefully designed experiments that measured the effects of axillary antiperspirant application on whole body sweat rate and body core temperature, following a regimen of exercise-induced heat stress in a hot environment in human volunteers. Our data show clearly that although antiperspirant prevents sweat production in the axillary area, this does not impact the ability of the body to thermoregulate following a rise in body core temperature. Thus, recent consumer questioning over this aspect of antiperspirant use appears to be unwarranted.

Sweat osmolarity shows intra-animal regional variation in the horse.

PubMed

Potts, Samantha; Thatcher, Rhys; Jones, Arwel W; Warren, Lori K; Tenbroeck, Saundra H; Nottage, Florence; McEwan, Neil R

2015-10-01

Sweating is important in regulating body temperature but can be a source of loss of both fluids and electrolytes. Although the process has been studied in horses, the variation in sweat osmolarity across the body has not. This work describes an investigation to determine if there is regional variation in the osmolarity of sweat across different anatomical regions of the horse. Ten horses were used in the study and were animals either stabled for riding lessons or had livery on-site. Sweat samples were collected from five regions on each horse following exercise and the osmolarity measurements were made using an Osmomat 030 (Gonotec, Berlin, Germany). Values were analysed by paired t-tests and analysis of variance. Samples from the back and ears had statistically (P < 0.05) lower osmolarity values than those seen for the neck and forelimb, with thigh values intermediate between the other two sets of values. Previous studies have used osmolarity values based on the sweat collected from the horse's back. The current work demonstrates that these values are probably an underestimation of electrolyte loss, which may have implications for the composition and administration of rehydration compounds. © 2015 ESVD and ACVD.

Realistic facial expression of virtual human based on color, sweat, and tears effects.

PubMed

Alkawaz, Mohammed Hazim; Basori, Ahmad Hoirul; Mohamad, Dzulkifli; Mohamed, Farhan

2014-01-01

Generating extreme appearances such as scared awaiting sweating while happy fit for tears (cry) and blushing (anger and happiness) is the key issue in achieving the high quality facial animation. The effects of sweat, tears, and colors are integrated into a single animation model to create realistic facial expressions of 3D avatar. The physical properties of muscles, emotions, or the fluid properties with sweating and tears initiators are incorporated. The action units (AUs) of facial action coding system are merged with autonomous AUs to create expressions including sadness, anger with blushing, happiness with blushing, and fear. Fluid effects such as sweat and tears are simulated using the particle system and smoothed-particle hydrodynamics (SPH) methods which are combined with facial animation technique to produce complex facial expressions. The effects of oxygenation of the facial skin color appearance are measured using the pulse oximeter system and the 3D skin analyzer. The result shows that virtual human facial expression is enhanced by mimicking actual sweating and tears simulations for all extreme expressions. The proposed method has contribution towards the development of facial animation industry and game as well as computer graphics.

Realistic Facial Expression of Virtual Human Based on Color, Sweat, and Tears Effects

PubMed Central

Alkawaz, Mohammed Hazim; Basori, Ahmad Hoirul; Mohamad, Dzulkifli; Mohamed, Farhan

2014-01-01

Generating extreme appearances such as scared awaiting sweating while happy fit for tears (cry) and blushing (anger and happiness) is the key issue in achieving the high quality facial animation. The effects of sweat, tears, and colors are integrated into a single animation model to create realistic facial expressions of 3D avatar. The physical properties of muscles, emotions, or the fluid properties with sweating and tears initiators are incorporated. The action units (AUs) of facial action coding system are merged with autonomous AUs to create expressions including sadness, anger with blushing, happiness with blushing, and fear. Fluid effects such as sweat and tears are simulated using the particle system and smoothed-particle hydrodynamics (SPH) methods which are combined with facial animation technique to produce complex facial expressions. The effects of oxygenation of the facial skin color appearance are measured using the pulse oximeter system and the 3D skin analyzer. The result shows that virtual human facial expression is enhanced by mimicking actual sweating and tears simulations for all extreme expressions. The proposed method has contribution towards the development of facial animation industry and game as well as computer graphics. PMID:25136663

Orally administered ketoconazole: route of delivery to the human stratum corneum.

PubMed Central

Harris, R; Jones, H E; Artis, W M

1983-01-01

Delivery of ketoconazole to human stratum corneum was studied. Thirteen healthy volunteers, three patients with chronic fungal disease and one patient with palmar-plantar hyperhidrosis were given 400 mg of ketoconazole daily for various lengths of time. The ketoconazole content of palmar stratum corneum, eccrine sweat, sebum, and serum was measured by high-pressure liquid chromatography (sensitivity, 0.005 to 0.010 microgram/ml). Palmar stratum corneum obtained after 7 and 14 days of daily administration contained up to 14 micrograms of ketoconazole per g. Ketoconazole was not found in sebum after 7 or 14 days of daily ingestion of the antimycotic agent. Sebum from three patients with chronic fungal infection treated for greater than 9 months contained ketoconazole (means, 4.7 micrograms/g). Thermogenic whole body eccrine sweat contained a mean of 0.059 microgram/ml on day 7 and 0.084 microgram/ml on day 14 of daily administration. Ketoconazole appeared in thermogenic whole body eccrine sweat and palmar hyperhidrotic sweat within 1 h after a single oral dose. Partition studies of ketoconazole containing eccrine sweat demonstrated a 10-fold greater concentration in the sediment phase (desquamated keratinocytes) compared with the clear supernatant phase. In vitro studies with [3H]ketoconazole-supplemented supernatant sweat revealed preferential binding to stratum corneum, hair, and nails and its partitioning to lipid-rich sebum. We conclude that eccrine sweat rapidly transports ketoconazole across the blood-skin barrier, where it may bind or partition to keratinocytes and surface lipids. PMID:6318663

Thermoregulatory vs. event sweating--comparison of clinical methodologies, physiology and results.

PubMed

Biehle-Hulette, S J; Krailler, J M; Elstun, L T; Bentz, S; Benzing, K W; Spruell, R D; Hellhammer, J; Swaile, D F

2014-02-01

Although the mechanisms of sweating due to thermoregulation vs. stress are distinct, the antiperspirant industry focuses primarily on perspiration due to heat as their method of efficacy testing. To better understand the overall protection afforded by a 'Clinical Strength' over-the-counter antiperspirant product, we compare results from a standard hot-room study with results from two studies using the Trier Social Stress Test (TSST). For each study, unscented antiperspirant was applied to one axilla, leaving the other untreated for internal control. The hot-room protocol involved a 40-min warm-up period with 2-20 min sweat collections at 100 ± 2 °F (35% RH). The TSST requires naïve subjects to give an impromptu speech and conduct mental arithmetic, with collections of sweat, heart rate and other biomarkers of stress before, during and after the event. During the TSST, heart rate and salivary cortisol data indicate significant emotional stress. Wetness results show that sweat was reduced by 69.4% in the hot-room study, compared with 83.7% and 89.3% reductions in the stress studies. We have found added value in investigating antiperspirancy from several causes of sweat production to give a more encompassing picture of the protection afforded by an antiperspirant product, specifically wetness protection from heat, activity and stress-induced sweat. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

The effect of exercise on water balance in premenopausal physically active women.

PubMed

Weinheimer, Eileen M; Martin, Berdine R; Weaver, Connie M; Welch, Jo M; Campbell, Wayne W

2008-10-01

This controlled feeding study examined the effects of exercise on daily water intake (particularly ad libitum water intake), water output, whole-body water balance, and hydration status in physically active, premenopausal women. The randomized crossover design consisted of three 8-day trials: placebo and no exercise, placebo and exercise (1-hour cycling bout per day at 65%-70% of heart rate reserve), and 800 mg calcium supplementation and exercise. During each trial, controlled quantities of the same foods and beverages were provided and ad libitum water intake was quantified. Water input included measured water from foods and beverages, measured ad libitum intake, and estimated metabolic production. Water output included measured losses in urine and stool, and estimated insensible losses from respiration and non-sweating perspiration (insensible diffusion through the skin). Participants were 26 women, age 25+/-5 years, body mass index 22+/-2, and VO(2peak) 43+/-6 mLxkg(-1)xmin(-1) (mean+/-standard deviation). Ad libitum water intake was 363 g/day more (P<0.05) for the placebo and exercise (1,940+/-654 g/day) and calcium supplementation and exercise (1,935+/-668 g/day) trials, compared with placebo and no exercise trial (1,575+/-667 g/day), and total water input was correspondingly higher in placebo and exercise and calcium supplementation and exercise trials compared with the placebo and no exercise trial. Urine, stool, and total water outputs were not different among trials. Apparent net water balance (representative of sweat water output) was 367 g/day more (P<0.05) in placebo and exercise (679+/-427 g/day) and calcium supplementation and exercise (641+/-519 g/day) trials compared with placebo and no exercise trial (293+/-419 g/day). Hydration status was clinically normal during all three trials. Calcium supplementation did not influence water balance. These results support that young, physically active women can completely compensate for exercise-induced sweat losses by increasing ad libitum water intake, and not decreasing non-sweat water outputs or impairing hydration status.

10 CFR Appendix B to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Freezers

Code of Federal Regulations, 2014 CFR

2014-01-01

... factor. 1.2 “Anti-sweat heater” means a device incorporated into the design of a freezer to prevent the accumulation of moisture on exterior or interior surfaces of the cabinet. 1.3 “Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat...

Sweat collection capsule

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Delaplaine, R. W. (Inventor)

1980-01-01

A sweat collection capsule permitting quantitative collection of sweat is described. The device consists of a frame held immobile on the skin, a closure secured to the frame and absorbent material located next to the skin in a cavity formed by the frame and the closure. The absorbent material may be removed from the device by removing the closure from the frame while the frame is held immobile on the skin.

Validity and reliability of a field technique for sweat Na+ and K+ analysis during exercise in a hot‐humid environment

PubMed Central

Baker, Lindsay B.; Ungaro, Corey T.; Barnes, Kelly A.; Nuccio, Ryan P.; Reimel, Adam J.; Stofan, John R.

2014-01-01

Abstract This study compared a field versus reference laboratory technique for extracting (syringe vs. centrifuge) and analyzing sweat [Na+] and [K+] (compact Horiba B‐722 and B‐731, HORIBA vs. ion chromatography, HPLC) collected with regional absorbent patches during exercise in a hot‐humid environment. Sweat samples were collected from seven anatomical sites on 30 athletes during 1‐h cycling in a heat chamber (33°C, 67% rh). Ten minutes into exercise, skin was cleaned/dried and two sweat patches were applied per anatomical site. After removal, one patch per site was centrifuged and sweat was analyzed with HORIBA in the heat chamber (CENTRIFUGE HORIBA) versus HPLC (CENTRIFUGE HPLC). Sweat from the second patch per site was extracted using a 5‐mL syringe and analyzed with HORIBA in the heat chamber (SYRINGE HORIBA) versus HPLC (SYRINGE HPLC). CENTRIFUGE HORIBA, SYRINGE HPLC, and SYRINGE HORIBA were highly related to CENTRIFUGE HPLC ([Na+]: ICC = 0.96, 0.94, and 0.93, respectively; [K+]: ICC = 0.87, 0.92, and 0.84, respectively), while mean differences from CENTRIFUGE HPLC were small but usually significant ([Na+]: 4.7 ± 7.9 mEql/L, −2.5 ± 9.3 mEq/L, 4.0 ± 10.9 mEq/L (all P < 0.001), respectively; [K+]: 0.44 ± 0.52 mEq/L (P < 0.001), 0.01 ± 0.49 mEq/L (P = 0.77), 0.50 ± 0.48 mEq/L (P < 0.001), respectively). On the basis of typical error of the measurement results, sweat [Na+] and [K+] obtained with SYRINGE HORIBA falls within ±15.4 mEq/L and ±0.68 mEq/L, respectively, of CENTRIFUGE HPLC 95% of the time. The field (SYRINGE HORIBA) method of extracting and analyzing sweat from regional absorbent patches may be useful in obtaining sweat [Na+] when rapid estimates in a hot‐humid field setting are needed. PMID:24793982

Metabolite Biometrics for the Differentiation of Individuals.

PubMed

Hair, Mindy E; Mathis, Adrianna I; Brunelle, Erica K; Halámková, Lenka; Halámek, Jan

2018-04-17

Sweat is a biological fluid present on the skin surface of every individual and is known to contain amino acids as well as other low molecular weight compounds. (1) Each individual is inherently different from one another based on certain factors including, but not limited to, his/her genetic makeup, environment, and lifestyle. As such, the biochemical composition of each person greatly differs. The concentrations of the biochemical content within an individual's sweat are largely controlled by metabolic processes within the body that fluctuate regularly based on attributes such as age, sex, and activity level. Therefore, the concentrations of these sweat components are person-specific and can be exploited, as presented here, to differentiate individuals based on trace amounts of sweat. For this concept, we analyzed three model compounds-lactate, urea, and glutamate. The average absorbance change from each compound in sweat was determined using three separate bioaffinity-based systems: lactate oxidase coupled with horseradish peroxidase (LOx-HRP), urease coupled with glutamate dehydrogenase (UR-GlDH), and glutamate dehydrogenase alone (GlDH). After optimization of a linear dependence for each assay to its respective analyte, analysis was performed on 50 mimicked sweat samples. Additionally, a collection and extraction method was developed and optimized by our group to evaluate authentic sweat samples from the skin surface of 25 individuals. A multivariate analysis of variance (MANOVA) test was performed to demonstrate that these three single-analyte enzymatic assays were effectively used to identify each person in both sample sets. This novel sweat analysis approach is capable of differentiating individuals, without the use of DNA, based on the collective responses from the chosen metabolic compounds in sweat. Applications for this newly developed, noninvasive analysis can include the field of forensic science in order to differentiate between individuals as well as the fields of homeland security and cybersecurity for personal authentication via unlocking mechanisms in smart devices that monitor metabolites. Through further development and analysis, this concept also has the potential to be clinically applicable in monitoring the health of individuals based on particular biomarker combinations.

Sweat sodium loss influences serum sodium concentration in a marathon.

PubMed

Lara, B; Salinero, J J; Areces, F; Ruiz-Vicente, D; Gallo-Salazar, C; Abián-Vicén, J; Del Coso, J

2017-02-01

The aim of this investigation was to determine the influence of sweat electrolyte concentration on body water and electrolyte homeostasis during a marathon. Fifty-one runners completed a marathon race in a warm and dry environment (24.4 ± 3.6 °C). Runners were classified as low-salt sweaters (n = 21; <30 mmol/L of sweat Na + concentration), typical sweaters (n = 20; ≥30 and <60 mmol/L of sweat Na + concentration), and salty sweaters (n = 10; ≥60 mmol/L of sweat Na + concentration). Before and after the race, body mass and a sample of venous blood were obtained. During the race, sweat samples were collected by using sweat patches, and fluid and electrolyte intake were recorded by using self-reported questionnaires. Low-salt, typical and salty sweaters presented similar sweat rates (0.93 ± 0.2, 0.92 ± 0.29, 0.99 ± 0.21 L/h, respectively), body mass changes (-3.0 ± 1.0, -3.3 ± 1.0, -3.2 ± 0.8%), total Na + intake (12.7 ± 8.1, 11.5 ± 9.7, 14.5 ± 16.6 mmol), and fluid intake (1.3 ± 0.8, 1.2 ± 0.8, 1.2 ± 0.6 L) during the race. However, salty sweaters presented lower post-race serum Na + concentration (140.8 ± 1.3 vs 142.5 ± 1.1, 142.4 ± 1.4 mmol/L; P < 0.01) and serum osmolality (297 ± 6 vs 299 ± 5, 301 ± 6 mOsm/kg; P < 0.05) than low-salt and typical sweaters. Sweat electrolyte concentration could influence post-race serum electrolyte concentration in the marathon. However, even the saltiest sweaters did not develop exercise-associated hyponatremia or associated symptoms. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Dehydration

MedlinePlus

... Diabetes - dehydration; Stomach flu - dehydration; Gastroenteritis - dehydration; Excessive sweating - dehydration ... body may lose a lot of fluid from: Sweating too much, for example, from exercising in hot ...

PIXE analysis of cystic fibrosis sweat samples with an external proton beam

NASA Astrophysics Data System (ADS)

Sommer, F.; Massonnet, B.

1987-03-01

PIXE analysis with an external proton beam is used to study, in four control and five cystic fibrosis children, the elemental composition of sweat samples collected from different parts of the body during entire body hyperthermia. We observe no significant difference of sweat rates and of temperature variations between the two groups during sweat test. The statistical study of results obtained by PIXE analysis allows us to pick out amongst 8 elements studied, 6 elements (Na, Cl, Ca, Mn, Cu, Br) significatively different between the two groups of subjects. Using regression analysis, Na, Cl and Br concentrations could be used in a predictive equation of the state of health.

Evaluation of atomic layer deposited alumina as a protective layer for domestic silver articles: Anti-corrosion test in artificial sweat

NASA Astrophysics Data System (ADS)

Park, Suk Won; Han, Gwon Deok; Choi, Hyung Jong; Prinz, Fritz B.; Shim, Joon Hyung

2018-05-01

This study evaluated the effectiveness of alumina fabricated by atomic layer deposition (ALD) as a protective coating for silver articles against the corrosion caused by body contact. An artificial sweat solution was used to simulate body contact. ALD alumina layers of varying thicknesses ranging from 20 to 80 nm were deposited on sputtered silver samples. The stability of the protective layer was evaluated by immersing the coated samples in the artificial sweat solution at 25 and 35 °C for 24 h. We confirmed that a sufficiently thick layer of ALD alumina is effective in protecting the shape and light reflectance of the underlying silver, whereas the uncoated bare silver is severely degraded by the artificial sweat solution. Inductively coupled plasma mass spectrometry and X-ray photoelectron spectroscopy were used for in-depth analyses of the chemical stability of the ALD-coated silver samples after immersion in the sweat solution.

Analysis of evaporative water loss in the Skylab astronauts

NASA Technical Reports Server (NTRS)

Leonard, J. I.

1977-01-01

Daily evaporative water losses (EWL) during the three Skylab missions were measured using the indirect mass and water balance techniques. A mean inflight EWL of 860 ml/day-m 2 was obtained for nine men who averaged one hour of daily exercise. Although it was expected the EWL would increase in the hypobaric environment of Skylab (1/3 atmosphere), an average decrease from preflight sea level conditions of 11 percent was measured. The results suggest that weightlessness may have been a factor in modifying EWL primarily by decreasing sweat losses during exercise and possibly by reducing insensible skin losses as well. The weightless environment apparently promotes the formation of a sweat film on the skin surface both directly, by reducing heat and mass convective flow and sweat drippage, and perhaps indirectly by inducing measurable biochemical changes resulting in high initial sweating rates. It is proposed that these high levels of skin wettedness favor sweat suppression by a previously described mechanism.

Objective evaluation of cutaneous thermal sensivity

NASA Technical Reports Server (NTRS)

Vanbeaumont, W.

1972-01-01

The possibility of obtaining reliable and objective quantitative responses was investigated under conditions where only temperature changes in localized cutaneous areas evoked measurable changes in remote sudomotor activity. Both male and female subjects were studied to evaluate sex difference in thermal sensitivity. The results discussed include: sweat rate responses to contralateral cooling, comparison of sweat rate responses between men and women to contralateral cooling, influence of the menstrual cycle on the sweat rate responses to contralateral cooling, comparison of threshold of sweating responses between men and women, and correlation of latency to threshold for whole body sweating. It is concluded that the quantitative aspects of the reflex response is affected by both the density and activation of receptors as well as the rate of heat loss; men responded 8-10% more frequently than women to thermode cooling, the magnitude of responses being greater for men; and women responded 7-9% more frequently to thermode cooling on day 1 of menstruation, as compared to day 15.

Inhibition of neuropeptide degradation suppresses sweating but increases the area of the axon reflex flare.

PubMed

Schlereth, Tanja; Breimhorst, Markus; Werner, Nicolas; Pottschmidt, Katrin; Drummond, Peter D; Birklein, Frank

2013-04-01

The neuropeptides CGRP (calcitonin gene-elated peptide) and substance P (SP) mediate neurogenic inflammation. Both are degraded by the neutral endopeptidase (NEP) which can be blocked by phosphoramidon. The aim was to evaluate the effect of NEP inhibition on sweating and vasodilatation. Dermal microdialysis was performed on the skin of 39 subjects. Two fibres were perfused with phosphoramidon (0.01%, 0.02% or 0.2%), two with saline. Acetylcholine (ACh) was either added to the microdialysis perfusate (n = 30, 10(-2)  m) or thermoregulatory sweating was induced (n = 9). Co-application of phosphoramidon reduced cholinergic and thermoregulatory sweating. However, the flare size - a localized increase in superficial blood flow after ACh-application - was significantly increased. The increase in flare size is most probably due to increased CGRP levels. The inhibition of sweating by phosphoramidon may involve an increase in SP, a reduction in CGRP-degradation fragments or a direct inhibitory action of phosphoramidon. © 2013 John Wiley & Sons A/S.

Measurements of clothing evaporative resistance using a sweating thermal manikin: an overview

PubMed Central

WANG, Faming

2017-01-01

Evaporative resistance has been widely used to describe the evaporative heat transfer property of clothing. It is also a critical variable in heat stress models for predicting human physiological responses in various environmental conditions. At present, sweating thermal manikins provide a fast and cost-effective way to determine clothing evaporative resistance. Unfortunately, the measurement repeatability and reproducibility of evaporative resistance are rather low due to the complicated moisture transfer processes through clothing. This review article presents a systematical overview on major influential factors affecting the measurement precision of clothing evaporative resistance measurements. It also illustrates the state-of-the-art knowledge on the development of test protocol to measure clothing evaporative resistance by means of a sweating manikin. Some feasible and robust test procedures for measurement of clothing evaporative resistance using a sweating manikin are described. Recommendations on how to improve the measurement accuracy of clothing evaporative resistance are addressed and expected future trends on development of advanced sweating thermal manikins are finally presented. PMID:28566566

Physiological Effects of Chemical Protective Garments During Exercise and Heat Stress.

DTIC Science & Technology

1998-01-01

The present study was designed to examine the effect of protective garments , with a range of insulation and permeability characteristics, on changes...Pre- and post-experiment nude and clothed weights were measured and used to calculate sweat production (SP) and sweat loss (SL). TAP and RAIN had...environment compared to warm conditions. Sweat production was significantly increased as suits became less permeable and as the temperature increased from

10 CFR Appendix A1 to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Electric Refrigerators and Electric...

Code of Federal Regulations, 2012 CFR

2012-01-01

... less for the freezing and storage of ice. 1.3“Anti-sweat heater” means a device incorporated into the... interior surfaces of the cabinet. 1.4“Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters. 1.5“Automatic defrost” means a...

10 CFR Appendix A to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Electric Refrigerators and Electric...

Code of Federal Regulations, 2012 CFR

2012-01-01

... capacity (14.2 liters) or less for the freezing and storage of ice. 1.3“Anti-sweat heater” means a device... on the exterior or interior surfaces of the cabinet. 1.4“Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters. 1.5...

10 CFR Appendix B1 to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Freezers

Code of Federal Regulations, 2014 CFR

2014-01-01

... defined in HRF-1-1979 in cubic feet, times (2) an adjustment factor. 1.2 “Anti-sweat heater” means a... interior surfaces of the cabinet. 1.3 “Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters. 1.4 “Automatic Defrost” means a...

10 CFR Appendix A to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Electric Refrigerators and Electric...

Code of Federal Regulations, 2014 CFR

2014-01-01

... capacity (14.2 liters) or less for the freezing and storage of ice. 1.3 “Anti-sweat heater” means a device... on the exterior or interior surfaces of the cabinet. 1.4 “Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters. 1.5...

10 CFR Appendix B1 to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Freezers

Code of Federal Regulations, 2012 CFR

2012-01-01

... defined in HRF-1-1979 in cubic feet, times (2) an adjustment factor. 1.2“Anti-sweat heater” means a device... surfaces of the cabinet. 1.3“Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters. 1.4“Automatic Defrost” means a system in...

10 CFR Appendix B1 to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Freezers

Code of Federal Regulations, 2013 CFR

2013-01-01

... defined in HRF-1-1979 in cubic feet, times (2) an adjustment factor. 1.2“Anti-sweat heater” means a device... surfaces of the cabinet. 1.3“Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters. 1.4“Automatic Defrost” means a system in...

10 CFR Appendix A1 to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Electric Refrigerators and Electric...

Code of Federal Regulations, 2014 CFR

2014-01-01

... less for the freezing and storage of ice. 1.3 “Anti-sweat heater” means a device incorporated into the... interior surfaces of the cabinet. 1.4 “Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters. 1.5 “Automatic defrost” means a...

10 CFR Appendix A to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Electric Refrigerators and Electric...

Code of Federal Regulations, 2013 CFR

2013-01-01

... capacity (14.2 liters) or less for the freezing and storage of ice. 1.3“Anti-sweat heater” means a device... on the exterior or interior surfaces of the cabinet. 1.4“Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters. 1.5...

Human Elimination of Organochlorine Pesticides: Blood, Urine, and Sweat Study

PubMed Central

Lane, Kevin; Birkholz, Detlef

2016-01-01

Background. Many individuals have been exposed to organochlorinated pesticides (OCPs) through food, water, air, dermal exposure, and/or vertical transmission. Due to enterohepatic reabsorption and affinity to adipose tissue, OCPs are not efficiently eliminated from the human body and may accrue in tissues. Many epidemiological studies demonstrate significant exposure-disease relationships suggesting OCPs can alter metabolic function and potentially lead to illness. There is limited study of interventions to facilitate OCP elimination from the human body. This study explored the efficacy of induced perspiration as a means to eliminate OCPs. Methods. Blood, urine, and sweat (BUS) were collected from 20 individuals. Analysis of 23 OCPs was performed using dual-column gas chromatography with electron-capture detectors. Results. Various OCPs and metabolites, including DDT, DDE, methoxychlor, endrin, and endosulfan sulfate, were excreted into perspiration. Generally, sweat samples showed more frequent OCP detection than serum or urine analysis. Many OCPs were not readily detected in blood testing while still being excreted and identified in sweat. No direct correlation was found among OCP concentrations in the blood, urine, or sweat compartments. Conclusions. Sweat analysis may be useful in detecting some accrued OCPs not found in regular serum testing. Induced perspiration may be a viable clinical tool for eliminating some OCPs. PMID:27800487

The development and initial validation of a virtual dripping sweat rate and a clothing wetness ratio for use in predictive heat strain models.

PubMed

Kubota, H; Kuwabara, K; Hamada, Y

2014-08-01

This paper applies the heat balance equation (HBE) for clothed subjects as a linear function of mean skin temperature (t sk ) by a new sweating efficiency (η sw ) and an approximation for the thermoregulatory sweat rate. The equation predicting t sk in steady state conditions was derived as the solution of the HBE and used for a predictive heat strain scale. The heat loss from the wet clothing (WCL) area was identified with a new variable of 'virtual dripping sweat rate VDSR' (S wdr ). This is a subject's un-evaporated sweat rate in dry clothing from the regional sweat rate exceeding the maximum evaporative capacity, and adds the moisture to the clothing, reducing the intrinsic clothing insulation. The S wdr allowed a mass balance analysis of the wet clothing area identified as clothing wetness (w cl ). The w cl was derived by combining the HBE at the WCL surface from which the evaporation rate and skin heat loss from WCL region are given. Experimental results on eight young male subjects wearing typical summer clothing, T-shirt and trousers verified the model for predicting t sk with WCL thermal resistance (R cl,w ) identified as 25 % of dry clothing (R cl,d ).

Autosomal recessive hyponatremia due to isolated salt wasting in sweat associated with a mutation in the active site of Carbonic Anhydrase 12.

PubMed

Muhammad, Emad; Leventhal, Neta; Parvari, Galit; Hanukoglu, Aaron; Hanukoglu, Israel; Chalifa-Caspi, Vered; Feinstein, Yael; Weinbrand, Jenny; Jacoby, Harel; Manor, Esther; Nagar, Tal; Beck, John C; Sheffield, Val C; Hershkovitz, Eli; Parvari, Ruti

2011-04-01

Genetic disorders of excessive salt loss from sweat glands have been observed in pseudohypoaldosteronism type I (PHA) and cystic fibrosis that result from mutations in genes encoding epithelial Na+ channel (ENaC) subunits and the transmembrane conductance regulator (CFTR), respectively. We identified a novel autosomal recessive form of isolated salt wasting in sweat, which leads to severe infantile hyponatremic dehydration. Three affected individuals from a small Bedouin clan presented with failure to thrive, hyponatremic dehydration and hyperkalemia with isolated sweat salt wasting. Using positional cloning, we identified the association of a Glu143Lys mutation in carbonic anhydrase 12 (CA12) with the disease. Carbonic anhydrase is a zinc metalloenzyme that catalyzes the reversible hydration of carbon dioxide to form a bicarbonate anion and a proton. Glu143 in CA12 is essential for zinc coordination in this metalloenzyme and lowering of the protein-metal affinity reduces its catalytic activity. This is the first presentation of an isolated loss of salt from sweat gland mimicking PHA, associated with a mutation in the CA12 gene not previously implicated in human disorders. Our data demonstrate the importance of bicarbonate anion and proton production on salt concentration in sweat and its significance for sodium homeostasis.

Morphology of human sweat ducts observed by optical coherence tomography and their frequency of resonance in the terahertz frequency region

NASA Astrophysics Data System (ADS)

Tripathi, Saroj R.; Miyata, Eisuke; Ishai, Paul Ben; Kawase, Kodo

2015-03-01

It is crucial to understand the various biological effects induced by terahertz (THz) electromagnetic waves with the rapid development of electronic and photonic devices operating in the THz frequency region. The presence of sweat glands plays an important role in THz wave interactions with human skin. We investigated the morphological features of sweat ducts using optical coherence tomography (OCT) to further understand such phenomena. We observed remarkable features of the ducts, such as their clear helical structure. The intersubject and intrasubject variations in the diameter of sweat ducts were considerably smaller than the variations in other structural parameters, such as length and number of turns. Based on the sweat duct dimensions and THz dielectric properties of skin measured using terahertz time-domain spectroscopy (THz-TDS), we calculated the resonating frequency of the sweat duct under the assumption of it functioning as a helical antenna. Here, we show that the resonance frequency in the axial mode of operation lies in the THz wave region with a centre frequency of 0.44 +/- 0.07 THz. We expect that these findings will further our understanding of the various health consequences of the interaction of THz waves with human beings.

Human Elimination of Organochlorine Pesticides: Blood, Urine, and Sweat Study.

PubMed

Genuis, Stephen J; Lane, Kevin; Birkholz, Detlef

2016-01-01

Background . Many individuals have been exposed to organochlorinated pesticides (OCPs) through food, water, air, dermal exposure, and/or vertical transmission. Due to enterohepatic reabsorption and affinity to adipose tissue, OCPs are not efficiently eliminated from the human body and may accrue in tissues. Many epidemiological studies demonstrate significant exposure-disease relationships suggesting OCPs can alter metabolic function and potentially lead to illness. There is limited study of interventions to facilitate OCP elimination from the human body. This study explored the efficacy of induced perspiration as a means to eliminate OCPs. Methods . Blood, urine, and sweat (BUS) were collected from 20 individuals. Analysis of 23 OCPs was performed using dual-column gas chromatography with electron-capture detectors. Results . Various OCPs and metabolites, including DDT, DDE, methoxychlor, endrin, and endosulfan sulfate, were excreted into perspiration. Generally, sweat samples showed more frequent OCP detection than serum or urine analysis. Many OCPs were not readily detected in blood testing while still being excreted and identified in sweat. No direct correlation was found among OCP concentrations in the blood, urine, or sweat compartments. Conclusions . Sweat analysis may be useful in detecting some accrued OCPs not found in regular serum testing. Induced perspiration may be a viable clinical tool for eliminating some OCPs.

The development and initial validation of a virtual dripping sweat rate and a clothing wetness ratio for use in predictive heat strain models

NASA Astrophysics Data System (ADS)

Kubota, H.; Kuwabara, K.; Hamada, Y.

2014-08-01

This paper applies the heat balance equation (HBE) for clothed subjects as a linear function of mean skin temperature ( t sk ) by a new sweating efficiency ( η sw ) and an approximation for the thermoregulatory sweat rate. The equation predicting t sk in steady state conditions was derived as the solution of the HBE and used for a predictive heat strain scale. The heat loss from the wet clothing (WCL) area was identified with a new variable of `virtual dripping sweat rate VDSR' ( S wdr ). This is a subject's un-evaporated sweat rate in dry clothing from the regional sweat rate exceeding the maximum evaporative capacity, and adds the moisture to the clothing, reducing the intrinsic clothing insulation. The S wdr allowed a mass balance analysis of the wet clothing area identified as clothing wetness ( w cl ). The w cl was derived by combining the HBE at the WCL surface from which the evaporation rate and skin heat loss from WCL region are given. Experimental results on eight young male subjects wearing typical summer clothing, T-shirt and trousers verified the model for predicting t sk with WCL thermal resistance ( R cl,w ) identified as 25 % of dry clothing ( R cl,d ).

A case of severe refractory chronic urticaria: a novel method for evaluation and treatment.

PubMed

Otto, Hans F; Calabria, Christopher W

2009-01-01

With cholinergic urticaria (ChU), the ultimate diagnosis often depends on the demonstration of characteristic urticaria by appropriate provocation. Several treatment options may be helpful but traditional options (antihistamines, leukotriene inhibitors, and immunosuppressives) may be exhausted by the refractory ChU patient. Here, we describe such a case. Demonstration of immediate hypersensitivity to autologous sweat skin testing (ASwST) may provide a rationale for use of omalizumab (Xolair, Genentech Novartis, South San Francisco, CA). Patients with severe ChU may have difficulty producing sufficient quantities of sweat for ASwST given that the very effort that produces the sample exacerbates ChU. Generation of sweat by iontophoresis with pilocarpine nitrate can be performed at many large medical centers. The procedure is simple, safe, and produces varying amounts of sweat depending on the individual. This sweat can then be used for ASwST. Our patient had a positive ASwST with appropriate positive and negative controls. Our testing methods were validated by negative ASwST, saline control, and positive histamine control in a nonatopic, nonurticarial control patient. By the patient's second injection of omalizumab, her quality of life score was significantly improved, as were her daily medication scores and exercise tolerance. We describe the first case of a patient with severe refractory ChU who had a positive ASwST by a novel collection method who has been successfully treated with omalizumab. We present a novel tool for the evaluation and demonstration of sweat-specific IgE in ChU patients who are unable to provide sweat by more traditional means.

The use of sweat to monitor lead absorption through the skin.

PubMed

Lilley, S G; Florence, T M; Stauber, J L

1988-10-15

It is usually assumed that lead can be absorbed through the skin only if it is present as an organolead compound such as tetraethyllead or lead naphthanate. It has been found, however, that finely-powdered lead metal or lead nitrate solution placed on the skin results in rapid absorption of lead, and transport of the metal around the body. The absorbed lead appears in sweat and saliva, but not in blood or urine. The application of 6 mg of lead as 0.5 M lead nitrate to the left arm resulted in an increase in lead concentration in pilocarpine-induced iontophoresis sweat samples taken from the right arm, from an initial value of 15-25 micrograms Pbl-1 to greater than 300 micrograms Pbl-1 after 2 days. Saliva lead increased from 2.5 to 15 micrograms Pbl-1 in the same period. The rate of lead absorption through the skin increases with increased sweating of the skin. Since no measurable increase in blood lead has been found, the lead must be transported in the plasma and rapidly concentrated into the extracellular fluid pool (sweat and saliva), without significant uptake by the erythrocytes, and with a very low transient concentration in the plasma. Workers occupationally exposed to lead have extremely high levels of lead in sweat even though their lead in blood is only moderately elevated. Lead absorbed through the skin may be eliminated via sweat and other extracellular fluids, and hence not be as great a health hazard as ingested lead, but this will need to be proved by further studies.

A new oil/membrane approach for integrated sweat sampling and sensing: sample volumes reduced from μL's to nL's and reduction of analyte contamination from skin.

PubMed

Peng, R; Sonner, Z; Hauke, A; Wilder, E; Kasting, J; Gaillard, T; Swaille, D; Sherman, F; Mao, X; Hagen, J; Murdock, R; Heikenfeld, J

2016-11-01

Wearable sweat biosensensing technology has dominantly relied on techniques which place planar-sensors or fluid-capture materials directly onto the skin surface. This 'on-skin' approach can result in sample volumes in the μL regime, due to the roughness of skin and/or due to the presence of hair. Not only does this increase the required sampling time to 10's of minutes or more, but it also increases the time that sweat spends on skin and therefore increases the amount of analyte contamination coming from the skin surface. Reported here is a first demonstration of a new paradigm in sweat sampling and sensing, where sample volumes are reduced from the μL's to nL's regime, and where analyte contamination from skin is reduced or even eliminated. A micro-porous membrane is constructed such that it is porous to sweat only. To complete a working device, first placed onto skin is a cosmetic-grade oil, secondly this membrane, and thirdly the sensors. As a result, spreading of sweat is isolated to only regions above the sweat glands before it reaches the sensors. Best case sampling intervals are on the order of several minutes, and the majority of hydrophilic (low oil solubility) contaminants from the skin surface are blocked. In vitro validation of this new approach is performed with an improved artificial skin including human hair. In vivo tests show strikingly consistent results, and reveal that the oil/membrane is robust enough to even allow horizontal sliding of a sensor.

The effect of water temperature and voluntary drinking on the post rehydration sweating.

PubMed

Hosseinlou, Abdollah; Khamnei, Saeed; Zamanlu, Masumeh

2013-01-01

During heat stress and dehydration, thermoregulation is partly suppressed to save body fluid and circulation. Drinking induces the recovery of thermoregulatory responses including sweating. Our objective is to investigate the effect of water temperature and voluntary drinking on the extent of the drinking-induced sweating. Six healthy subjects 23.7 ± 0.6 yr old and 80.7 ± 5.7 kg wt were dehydrated by performing mild exercise (ergometer cycling) in a hot and humid chamber (38-40°C, 20-28% relative humidity). After dehydration, subjects were allowed to drink water with temperatures of 5, 16, 26, 58°C on four separate days. The sweating rate was measured on the forehead area before and after drinking. Also, blood samples were collected during the experiments and plasma osmolality was measured. Sweating increased markedly just a few minutes after the onset of drinking. The rate of this response was lower in ingested water temperature of 5°C (0.43 ± 0.03 g, p = 0.000). Different intake occurred with different water temperatures (respectively 4.2, 6.4, 3.1, 1.8 ml/kg). Water at 16°C induced higher intake (6.4 ml/kg) together with lower sweating (0.54 ± 0.03 g), which can result in optimum level of hydration. Conclusion- When dehydrated subjects drink water with different temperatures, there are different sweating responses together with different voluntary intakes. According to our results, consuming 16°C water, cool tap water, could be suggested in dehydration.

Use of dew-point hygrometry, direct sweat collection, and measurement of body water losses to determine sweating rates in exercising horses.

PubMed

Kingston, J K; Geor, R J; McCutcheon, L J

1997-02-01

To compare dew-point hygrometry, direct sweat collection, and measurement of body water loss as methods for determination of sweating rate (SR) in exercising horses. 6 exercise-trained Thoroughbreds. SR was measured in 6 horses exercising at 40% of the speed that elicited maximum oxygen consumption for 45 km, with a 15-minute rest at the end of each 15-km phase. Each horse completed 2 exercise trials. Dew-point hygrometry, as a method of local SR determination, was validated in vitro by measurement of rate of evaporative water loss. During exercise, local SR was determined every 10 minutes by the following 2 methods: (1) dew-point hygrometry on the neck and lateral area of the thorax, and (2) on the basis of the volume of sweat collected from a sealed plastic pouch attached to the lateral area of the thorax. Mean whole body SR was calculated from total body water loss incurred during exercise. Evaporation rate measured by use of dew-point hygrometry was significantly correlated (r2 = 0.92) with the actual rate of evaporative water loss. There was a similar pattern of change in SR measured by dew-point hygrometry on the neck and lateral area of the thorax during exercise, with a significantly higher SR on the neck. The SR measured on the thorax by direct sweat collection and by dew-point hygrometry were of similar magnitude. Mean whole body SR calculated from total body water loss was not significantly different from mean whole body SR estimated from direct sweat collection or dew-point hygrometry measurements on the thorax. Dew-point hygrometry and direct sweat collection are useful methods for determination of local SR in horses during prolonged, steady-state exercise in moderate ambient conditions. Both methods of local SR determination provide an accurate estimated of whole body SR.

Cyclooxygenase inhibition does not alter methacholine-induced sweating

PubMed Central

Fujii, Naoto; McGinn, Ryan; Paull, Gabrielle; Stapleton, Jill M.; Meade, Robert D.

2014-01-01

Cholinergic agents (e.g., methacholine) induce cutaneous vasodilation and sweating. Reports indicate that either nitric oxide (NO), cyclooxygenase (COX), or both can contribute to cholinergic cutaneous vasodilation. Also, NO is reportedly involved in cholinergic sweating; however, whether COX contributes to cholinergic sweating is unclear. Forearm sweat rate (ventilated capsule) and cutaneous vascular conductance (CVC, laser-Doppler perfusion units/mean arterial pressure) were evaluated in 10 healthy young (24 ± 4 yr) adults (7 men, 3 women) at four skin sites that were continuously perfused via intradermal microdialysis with 1) lactated Ringer (control), 2) 10 mM ketorolac (a nonselective COX inhibitor), 3) 10 mM NG-nitro-l-arginine methyl ester (l-NAME, a nonselective NO synthase inhibitor), or 4) a combination of 10 mM ketorolac + 10 mM l-NAME. At the four skin sites, methacholine was simultaneously infused in a dose-dependent manner (1, 10, 100, 1,000, 2,000 mM). Relative to the control site, forearm CVC was not influenced by ketorolac throughout the protocol (all P > 0.05), whereas l-NAME and ketorolac + l-NAME reduced forearm CVC at and above 10 mM methacholine (all P < 0.05). Conversely, there was no main effect of treatment site (P = 0.488) and no interaction of methacholine dose and treatment site (P = 0.711) on forearm sweating. Thus forearm sweating (in mg·min−1·cm−2) from baseline up to the maximal dose of methacholine was not different between the four sites (at 2,000 mM, control 0.50 ± 0.23, ketorolac 0.44 ± 0.23, l-NAME 0.51 ± 0.22, and ketorolac + l-NAME 0.51 ± 0.23). We show that both NO synthase and COX inhibition do not influence cholinergic sweating induced by 1–2,000 mM methacholine. PMID:25213633

Hereditary ectodermal dysplasia: A retrospective study

PubMed Central

More, Chandramani B.; Bhavsar, Khusbhu; Joshi, Jigar; Varma, Saurabh N.; Tailor, Mansi

2013-01-01

Background: Ectodermal dysplasia (ED) is a group of rare, inherited disorders characterized by sparse hair, missing teeth and inability to sweat. Objective: To review and analyze cases of ED with an emphasis on clinical manifestations and parent's marriage history. Methodology: The present retrospective study was conducted by assessing the clinical records of nineteen cases of ED, available in the archives of the department; for age, gender, family history of consanguineous marriage and clinical manifestations. Results: It was observed that ED was more prevalent in males, with a ratio of 1.7:1. The hypohydrotic type was more common (78.95%) than hydrotic type (21.05%). The marriage history of parents revealed that 66.67% had consanguineous marriage and had 68.42% offspring's affected with ED; whereas 33.33% had history of non-consanguineous marriage and had 31.58% offspring's affected with ED. The clinical manifestations observed were- dry skin(94.74%); scaly skin(42.11%); sparse hair on scalp, eyebrows and eyelashes(100%); frontal bossing(63.18%); saddle nose (57.89%); hypertelorism (47.37%); nail abnormality(52.63%); normal sweat glands(21.05%); abnormal sweat glands(78.95%); hypoplastic maxilla(52.63%); protuberant lips (57.89%); palmo-plantar keratosis(21.05%); wrinkled & hyper pigmented facial skin(84.21%); partial anodontia(94.74%); conical shaped teeth(84.21%); high arched palate(68.42%); thin alveolar bone(100.00%); taurodontism(21.05%) and cleft lip & cleft palate(05.26%). The number of teeth present in all the cases ranged from 0 to 19. Conclusion: ED patients suffer from social problems and poor psychological and physiological development as a result of unacceptable esthetics and abnormal function of orofacial structures. Oral rehabilitation thus becomes mandatory, although it is often difficult; particularly in pediatric patients. PMID:24082749

10 CFR Appendix A1 to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Electric Refrigerators and Electric...

Code of Federal Regulations, 2010 CFR

2010-01-01

... freezer compartment volume as defined in HRF-1-1979, in cubic feet. 1.3“Anti-sweat heater” means a device... operating characteristics. 1.7“Standard cycle” means the cycle type in which the anti-sweat heater control... unit under test. Defrost controls are to be operative and the anti-sweat heater switch is to be “on...

10 CFR Appendix B1 to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Freezers

Code of Federal Regulations, 2010 CFR

2010-01-01

... Standard as a revision of ANSI B38.1-1970. 1.2“Anti-sweat heater” means a device incorporated into the... characteristics. 1.5“Standard cycle” means the cycle type in which the anti-sweat heater switch, when provided, is... controls are to be operative and the anti-sweat heater switch is to be “on” during one test and “off...

Voluntary drinking versus imposed drinking in the methodology of investigations about the drinking-induced thermoregulatory sweating

PubMed Central

Hosseinlou, Abdollah; Khamnei, Saeed; Zamanlu, Masumeh

2014-01-01

Studies have shown that dehydrated humans or animals in a warm environment begin to sweat within seconds to minutes after drinking. This phenomenon is one of the drinking-induced thermoregulatory responses; being investigated from different aspects. Our objective is to show the difference of voluntary drinking and imposed drinking in the methodology of these experiments. Six healthy subjects 23.7 ± 0.6 yr old and 80.7 ± 5.7 kg wt were dehydrated by performing mild exercise (ergometer cycling) in a hot and humid chamber (38-40°C, 20-28% relative humidity). We incorporated two protocols: after dehydration, subjects were allowed to drink water with 1) imposed volumes of 1, 3, 5 ml/kg and 2) voluntary volumes; on four separate days. The sweating rate was measured on the forehead area before and after drinking. Sweating increased markedly just a few minutes after the onset of drinking. The mean sweat rates of the imposed volumes of 1, 3, 5 ml/Kg were 0.33 ± 0.15, 0.31 ± 0.17, 0.47 ± 0.21 respectively and for the voluntary volume it was 0.54 ± 0.19. The mean intake in the voluntary trial was 6.58 ± 1.14 ml/Kg, more than the imposed volume of 5 ml/Kg. The trend of the rate of the sweating response in the imposed trials was distinct from the response in the voluntary trial. Conclusion: There exists a difference between voluntary drinking and imposed drinking in the sweating response that follows rehydration. So it is suggested to use the methods of voluntary drinking in the investigations of this phenomenon, to reveal the natural events that happen in the actual circumstances. PMID:25419429

Factors affecting heat illness when working in conditions of thermal stress.

PubMed

Bates, G; Gazey, C; Cena, K

1996-06-01

In hot working conditions, high sweat rates with excessive loss of body fluids may result in dehydration and electrolyte imbalance. It is well established that dehydration and/or electrolyte disturbances will impair work performance, and, if prolonged or severe, can pose a serious risk to health. The lesser condition of hypohydration is undoubtedly widespread in the workplace, and may be indirectly responsible for less than optimal performance and workplace accidents. With the aid of a new sweat collection method, fluid and electrolyte loss from a population of male workers with varying fitness and body composition has been documented. This has provided the basis for prescribing guidelines of fluid replacement when working in the heat. In addition, the minimum duration of heat exposure required to trigger heat acclimmatization was sought using sweat sodium as an indicator. Rehydration at the rate of 500 ml/h (250 ml every 30 min) is recommended for people working in all but extreme heat (> 45 degrees C). Electrolyte supplements (sodium and potassium) are not generally required in the workplace, but may be warranted in certain circumstances to avoid hyponatremia (> 3 h). The ability to predict the susceptibility of an individual to fluid and electrolyte disturbances cannot be made from age, body composition, ethnicity or VO2max, although a high VO2max appears to enhance heat tolerance. Sodium loss in sweat varies greatly and is not significantly related to sweat rate. Acclimatization results in a significant decrease in sweat sodium and increased sweat rate during summer compared with winter. This advantageous physiological adaptation requires a minimum of 9 h of heat exposure to initiate.

Sweat testing for the detection of atomoxetine from paediatric patients with attention deficit/ hyperactivity disorder: application to clinical practice.

PubMed

Marchei, Emilia; Papaseit, Esther; Garcia-Algar, Oscar; Bilbao, Amaia; Farré, Magí; Pacifici, Roberta; Pichini, Simona

2013-03-01

Atomoxetine (ATX) is a selective norepinephrine reuptake inhibitor approved since 2002 for the treatment of attention deficit hyperactivity disorder (ADHD) in children, adolescents, and adults as an alternative treatment to methylphenidate. Within the framework of a project evaluating the use of alternative biological matrices for therapeutic monitoring of psychoactive drugs in paediatric and non-paediatric individuals, the excretion of ATX and its principal metabolites has been recently studied in oral fluid and hair. The aim of this study was to describe the excretion profile of ATX and its metabolites 4-hydroxyatomoxetine (4-OH-ATX) and N-desmethylatomoxetine (N-des-ATX) in sweat following the administration of different dosage regimens (60, 40, 35, and 18 mg/day) of ATX to six paediatric patients. Sweat patches were applied to the back of each participant and removed at timed intervals. ATX and its metabolites were measured in patches using a previously validated liquid chromatography-tandem mass spectrometric (LC-MS/MS) method. Independently from the administered dose, ATX appeared in the sweat patches 1 h post administration and reached its maximum concentration generally at 24 h. Peak ATX concentrations ranged between 2.31 and 40.4 ng/patch and did not correlate with the administered drug dose, or with body surface area. Total ATX excreted in sweat ranged between 0.008 and 0.121 mg, corresponding to 0.02 and 0.3% of the administered drug. Neither 4-OH-ATX, nor N-des-ATX was detected in either of the collected sweat patches. Measuring ATX in sweat patches can provide information on cumulative drug use from patch application until removal. Copyright © 2012 John Wiley & Sons, Ltd.

The magnitude of ivacaftor effects on fluid secretion via R117H-CFTR channels: Human in vivo measurements

PubMed Central

Char, Jessica E.; Dunn, Colleen; Davies, Zoe; Milla, Carlos; Moss, Richard B.; Wine, Jeffrey J.

2017-01-01

We optically measured effects of orally available ivacaftor (Kalydeco®) on sweat rates of identified glands in 3 R117H subjects, each having a unique set of additional mutations, and compared them with 5 healthy control subjects tested contemporaneously. We injected β-adrenergic agonists intradermally to stimulate CFTR-dependent ‘C-sweat’ and methacholine to stimulate ‘M-sweat’, which persists in CF subjects. We focused on an R117H-7T/F508del subject who produced quantifiable C-sweat off ivacaftor and was available for 1 blinded, 3 off ivacaftor, and 3 on ivacaftor tests, allowing us to estimate in vivo fold-increase in sweat rates produced by ivacaftor’s effect on the open probability (PO) of R117H-CFTR. Measured sweat rates must be corrected for sweat losses. With estimated sweat losses of 0.023 to 0.08 nl·gland-1·min-1, ivacaftor increased the average C-sweat rates 3–7 fold, and estimated function as % of WT were 4.1–12% off ivacaftor and 21.9–32% on ivacaftor (larger values reflect increased loss estimates). Based on single tests, an R117H-7T/ R117H-7T subject showed 6–9% WT function off ivacaftor and 28–43% on ivacaftor. Repeat testing of an R117H-5T/F508del subject detected only trace responding to ivacaftor. We conclude that in vivo, R117H PO is strongly increased by ivacaftor, but channel number, mainly determined by variable deletion of exon 10, has a marked influence on outcomes. PMID:28419121

Age‐related differences in postsynaptic increases in sweating and skin blood flow postexercise

PubMed Central

Stapleton, Jill M.; Fujii, Naoto; McGinn, Ryan; McDonald, Katherine; Kenny, Glen P.

2014-01-01

Abstract The influence of peripheral factors on the control of heat loss responses (i.e., sweating and skin blood flow) in the postexercise period remains unknown in young and older adults. Therefore, in eight young (22 ± 3 years) and eight older (65 ± 3 years) males, we examined dose‐dependent responses to the administration of acetylcholine (ACh) and methacholine (MCh) for sweating (ventilated capsule), as well as to ACh and sodium nitroprusside (SNP) for cutaneous vascular conductance (CVC, laser‐Doppler flowmetry, % of max). In order to assess if peripheral factors are involved in the modulation of thermoeffector activity postexercise, pharmacological agonists were perfused via intradermal microdialysis on two separate days: (1) at rest (DOSE) and (2) following a 30‐min bout of exercise (Ex+DOSE). No differences in sweat rate between the DOSE and Ex+DOSE conditions at either ACh or MCh were observed for the young (ACh: P =0.992 and MCh: P =0.710) or older (ACh: P =0.775 and MCh: P =0.738) adults. Similarly, CVC was not different between the DOSE and Ex+DOSE conditions for the young (ACh: P =0.123 and SNP: P =0.893) or older (ACh: P =0.113 and SNP: P =0.068) adults. Older adults had a lower sweating response for both the DOSE (ACh: P =0.049 and MCh: P =0.006) and Ex+DOSE (ACh: P =0.050 and MCh: P =0.029) conditions compared to their younger counterparts. These findings suggest that peripheral factors do not modulate postexercise sweating and skin blood flow in both young and older adults. Additionally, sweat gland function is impaired in older adults, albeit the impairments were not exacerbated during postexercise recovery. PMID:25347861

Body odor aldehyde reduction by acetic acid bacterial extract including enzymes: alcohol dehydrogenase and aldehyde dehydrogenase.

PubMed

Yoshioka, N; Kurata, K; Takahashi, T; Ariizumi, M; Mori, T; Fujisawa, H; Kameyama, N; Okuyama, Y

2018-06-13

Body odor is mainly caused by secreted sweat. Although sweat is almost odorless immediately after secretion, decomposition or denaturation of components contained in sweat by bacteria on the skin surface contributes to unpleasant body odor. Body odor is due to various substances and aldehydes are primarily detected in body odor [1-4]. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Evaluation of the Joint Service General Purpose Mask, XM50

DTIC Science & Technology

2005-07-01

and vision Trial 7 Trial 8 Trial 12 correction E-2 TRIAL 3299 7795 2079 Did not finish exercises. No No comment on sweat or No comment on sweat or...lhr 50 min playing time). Duringboth activities, slight Reported slight intermittent No comment on. swet or fogging with slight impact on fogging...right eye. During steam No comment on Mask was stationary. engine exercise, reported 4 sweat or fogging Reported that seal mask seal leakage at

Characterization of X-linked Hypohidrotic Ectodermal Dysplasia (XL-HED) Hair and Sweat Gland Phenotypes Using Phototrichogram Analysis and Live Confocal Imaging

PubMed Central

Jones, Kyle B.; Goodwin, Alice F.; Landan, Maya; Seidel, Kerstin; Tran, Dong-Kha; Hogue, Jacob; Chavez, Miquella; Fete, Mary; Yu, Wenli; Hussein, Tarek; Johnson, Ramsey; Huttner, Kenneth; Jheon, Andrew H.; Klein, Ophir D.

2015-01-01

Hypohidrotic ectodermal dysplasia (HED) is the most common type of ectodermal dysplasia (ED), which encompasses a large group of syndromes that share several phenotypic features such as missing or malformed ectodermal structures, including skin, hair, sweat glands, and teeth. X-linked hypohidrotic ectodermal dysplasia (XL-HED) is associated with mutations in ectodysplasin (EDA1). Hypohidrosis due to hypoplastic sweat glands and thin, sparse hair are phenotypic features that significantly affect the daily lives of XL-HED individuals and therefore require systematic analysis. We sought to determine the quality of life of individuals with XL-HED and to quantify sweat duct and hair phenotypes using confocal imaging, pilocarpine iontophoresis, and phototrichogram analysis. Using these highly sensitive and non-invasive techniques, we demonstrated that 11/12 XL-HED individuals presented with a complete absence of sweat ducts and that none produced sweat. We determined that the thin hair phenotype observed in XL-HED was due to multiple factors, such as fewer terminal hairs with decreased thickness and slower growth rate, as well as fewer follicular units and fewer hairs per unit. The precise characterization of XL-HED phenotypes using sensitive and non-invasive techniques presented in our study will improve upon larger genotype-phenotype studies and in the assessment of future therapies in XL-HED. PMID:23687000

Determination of different recreational drugs in sweat by headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME GC/MS): Application to drugged drivers.

PubMed

Gentili, Stefano; Mortali, Claudia; Mastrobattista, Luisa; Berretta, Paolo; Zaami, Simona

2016-09-10

A procedure based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography/mass spectrometry (GC/MS) has been developed for the determination of most commonly used drugs of abuse in sweat of drivers stopped during roadside controls. DrugWipe 5A sweat screening device was used to collect sweat by a specific pad rubbed gently over forehead skin surface. The procedure involved an acid hydrolysis, a HS-SPME extraction for drugs of abuse but Δ(9)-tetrahydrocannabinol, which was directly extracted in alkaline medium HS-SPME conditions, a GC separation of analytes by a capillary column and MS detection by electron impact ionisation. The method was linear from the limit of quantification (LOQ) to 50ng drug per pad (r(2)≥0.99), with an intra- and inter-assay precision and accuracy always less than 15% and an analytical recovery between 95.1% and 102.8%, depending on the considered analyte. Using the validated method, sweat from 60 apparently intoxicated drivers were found positive to one or more drugs of abuse, showing sweat patches testing as a viable economic and simple alternative to conventional (blood and/or urine) and non conventional (oral fluid) testing of drugs of abuse in drugged drivers. Copyright © 2016 Elsevier B.V. All rights reserved.

Regional and circadian variations of sweating rate and body surface temperature in camels (Camelus dromedarius).

PubMed

Abdoun, Khalid A; Samara, Emad M; Okab, Aly B; Al-Haidary, Ahmed A

2012-07-01

It was the aim of this study to investigate the regional variations in surface temperature and sweating rate and to visualize body thermal windows responsible for the dissipation of excess body heat in dromedary camels. This study was conducted on five dromedary camels with mean body weight of 450 ± 20.5 kg and 2 years of age. Sweating rate, skin and body surface temperature showed significant (P < 0.001) circadian variation together with the variation in ambient temperature. However, daily mean values of sweating rate, skin and body surface temperature measured on seven regions of the camel body did not significantly differ. The variation in body surface temperature compared to the variation in skin temperature was higher in the hump compared to the axillary and flank regions, indicating the significance of camel's fur in protecting the skin from daily variation in ambient temperature. Infrared thermography revealed that flank and axillary regions had lower thermal gradients at higher ambient temperature (T(a) ) and higher thermal gradients at lower T(a) , which might indicate the working of flank and axillary regions as thermal windows dissipating heat during the night. Sweating rate showed moderate correlation to skin and body surface temperatures, which might indicate their working as potential thermal drivers of sweating in camels. © 2012 The Authors. Animal Science Journal © 2012 Japanese Society of Animal Science.

Desvenlafaxine

MedlinePlus

... or staying asleep, diarrhea, anxiety, extreme tiredness, unusual dreams, or sweating. Tell your doctor if you experience ... of appetite dry mouth dizziness extreme tiredness unusual dreams yawning sweating uncontrollable shaking of a part of ...

77 FR 76916 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-31

... Southeast. Sweat Mountain Creek At the Willeo Creek +941 Unincorporated Areas of confluence. Cobb County... upstream of the Sweat Mountain Creek confluence. * National Geodetic Vertical Datum. + North American...

EEMCO guidance for the efficacy assessment of antiperspirants and deodorants.

PubMed

Piérard, G E; Elsner, P; Marks, R; Masson, P; Paye, M

2003-01-01

Overproduction of sweat, sweaty skin and body odours are unpleasant for many social groups. Body cleansing products are designed to combat these undesirable features of skin. In addition, antiperspirant and deodorant products are more specifically used in the underarm site by a large part of the adult population. Antiperspirants are offered to control emotionally triggered sweating in the armpit. Deodorants are designed to combat malodour generated from bacteria-modified sweat. This review summarizes the physiology of eccrine, apocrine and apoeccrine sweat glands. The mechanisms of action of antiperspirants and deodorants are described as well as the factors influencing their efficacies. A series of tests using various measurement methods can be used to demonstrate the efficacy of antiperspirants. These include the gravimetric method, water evaporation quantification, electrodermal measurements, staining procedures, dye injections and cyanoacrylate skin surface strippings and casting replicas. Deodorant efficacy can be evaluated by sensory assessments performed by an expert panel. Indirect support is provided by visualization of apocrine gland excretion and collection of sweat and volatile compounds. Microbiological assessments and chromatographic analysis also provide indirect information. Copyright 2003 S. Karger AG, Basel

Development of emotional sweating in the newborn infant.

PubMed

Harpin, V A; Rutter, N

1982-09-01

Sweating from the palm and sole occurs independently of ambient temperature but is influenced by emotional factors. It thus provides a useful objective measure of emotional state. The development of this emotional sweating in the newborn was investigated by measuring palmar water loss and relating it to the infant's state of arousal. Although 433 individual measurements were made on 124 babies of gestational age 25 to 41 weeks and postnatal age 15 hours to 9 weeks. Palmar water loss was also recorded continuously in 22 infants undergoing heel prick for routine blood sampling. In babies of 37 weeks' gestation or more, there was a clear relationship between palmar water loss and arousal from the day of birth, and by the third week levels on vigorous crying were comparable with those of an anxious adult. Less mature babies did not show emotional sweating at birth; it was first seen at the equivalent of 36 to 37 weeks' gestation regardless of maturity. Continuous recordings confirmed the cross-sectional data and illustrated the abrupt nature of the response. Emotional sweating could be a useful tool for the assessment of emotional state of the newborn.

Artificial sweat enhances dermal transfer of chlorpyrifos from treated nylon carpet fibers.

PubMed

Williams, Ryan L; Reifenrath, William G; Krieger, Robert I

2005-01-01

The dermal transfer and absorption of 14C-ring-chlorpyrifos from nylon carpet fibers was measured in skin penetration-evaporation cells with excised pig skin. Prior to application, synthetic sweat was applied to skin in half of the cells. Radioactivity was measured in receptor fluid, dermis, epidermis, tape stripping samples, and vapor trap samples during a 24-h period. The sum of radiolabel recovered from the dermis and receptor fluid represented the absorbed dose. There was no significant difference (p > 0.05) in percutaneous absorption between cells that received the synthetic sweat application and "dry" cells (1.3 +/- 0.3% of applied dose). There was significantly more (p < 0.05) radiolabel recovered from tape stripping (5.4 +/- 2.1 vs. 2.8 +/- 0.6%) and in the epidermis (4.5 +/- 0.8 vs. 3.1 +/- 0.3%) from cells that received the synthetic sweat application, which indicated synthetic sweat facilitated transfer of chlorpyrifos from a treated substrate to the skin surface. The measured value for percutaneous absorption of chlorpyrifos agreed with the value predicted from an empirical model previously developed for nitro compound-containing soil.

Cystic Fibrosis

MedlinePlus

... is an inherited disease of the mucus and sweat glands. It affects mostly your lungs, pancreas, liver, ... through various tests, such as gene, blood, and sweat tests. There is no cure for CF, but ...

Genetics Home Reference: isolated hyperchlorhidrosis

MedlinePlus

... loss of salt (sodium chloride or NaCl) in sweat. In particular, "hyperchlorhidrosis" refers to the high levels of chloride found in sweat, although both sodium and chloride are released. Because ...

Your Skin

MedlinePlus

... contains nerve endings, blood vessels, oil glands, and sweat glands. It also contains collagen and elastin, which ... absorb water and get soggy. You also have sweat glands on your epidermis. Even though you can' ...

Influence of various environmental parameters on sweat gland activity.

PubMed

McMullen, Roger L; Gillece, Tim; Lu, Guojin; Laura, Donna; Chen, Susan

2013-01-01

The choice of environmental conditions when conducting antiperspirant studies greatly affects the quantity of sweat output. Our initial goal in this work was to develop an in-house procedure to test the efficacy of antiperspirant products using replica techniques in combination with image analysis. To ameliorate the skin replica method, we conducted rheological studies using dynamic mechanical analysis of the replica formulation. In terms of sweat output quantification, our preliminary results revealed a considerable amount of variation using the replica technique, leading us to conduct more fundamental studies of the factors that influence sweating behavior and how to best design the experimental strategy. In accordance with the FDA's protocol for antiperspirant testing, we carried out gravimetric analyses of axillae sweating under a variety of environmental conditions including temperature and humidity control. Subjects were first acclimatized in an environmentally controlled room for 30 min, and then placed in a sauna for an additional 30 or 45 min, depending on which test we administered. In Test 1 (30 min total in the sauna), the first 10 min in the sauna was another equilibration period, followed by a 20 min sweat production stage. We monitored axillae sweating during the last 20 min in the sauna by gravimetric analysis. At time (t) = 30 min in the sauna, skin replicas were taken and later analyzed using imaging and image analysis techniques. Test 1 was carried out on over 25 subjects, both male and female, from various racial backgrounds. In Test 2, subjects spent 45 min in the sauna after the initial 30-min period in the environmental room. During the 45 min, we obtained gravimetric readings of absorbent pads placed in the axillae. We conducted studies at various temperature and relative humidity settings. We also studied the influence of several external parameters on sudoriferous activity. Test 2 was a range-finding experiment on two subjects to determine the optimized environmental conditions for the hot room procedure. In addition to the replica and gravimetric techniques, we also measured flux density to determine the onset of firing of sweat glands to ensure that our environmental preconditioning step (30 min in the environmental room) brought subjects to the point that their sweat glands were activated. Although flux density measurements are usually carried out to determine transepidermal water loss (TEWL), we found that they can be equally useful for monitoring the onset of sweat production. Thermal infrared imaging experiments were also carried out allowing us to generate full-body images of subjects containing anatomical thermal distribution data with high accuracy. Overall, we conclude that our in-house hot room procedure offers much potential as an effective and cost-efficient screening tool for narrowing copious antiperspirant formulations to a select few for expensive clinical evaluation.

Low blood sugar

MedlinePlus

... Feeling cranky or acting aggressive Feeling nervous Headache Hunger Shaking or trembling Sweating Tingling or numbness of ... with nearly the same symptoms. Some symptoms, like hunger or sweating, occur when blood sugar is only ...

[Clinical manifestations and hazards of brucellosis in the Netherlands].

PubMed

Kaan, Jan A; Frakking, Florine N J; Arents, Nicolaas L A; Anten, Sander; Roest, Hendrik I J; Rothbarth, Ph H Flip

2012-01-01

Brucellosis, a zoonotic infection characterised by undulant fever, has a low incidence in the Netherlands and is therefore rarely considered. We describe 3 patients aged 26, 47 and 56 years old; each presented with long-standing fever as predominant symptom after having travelled to an endemic area, Iraq or Turkey, 1 week to 4 months prior to manifestation of illness. They had similar symptoms: fever, weight loss, chills, night sweats and dry cough. Blood cultures of all patients became positive for gram-negative rods after 3-4 days of incubation. One patient had imported and consumed sheep-milk cheese from which a genetically indistinguishable Brucella strain was cultured. In another patient, identification of the bacterium proved difficult, resulting in delayed prescription of adequate antibiotic treatment. Serologic testing confirmed the diagnosis in this case. In the laboratory, there is a considerable risk of airborne transmission of the disease necessitating clear notification of the suspicion of brucellosis when material for culturing is submitted.

Plasma aldosterone and sweat sodium concentrations after exercise and heat acclimation

NASA Technical Reports Server (NTRS)

Kirby, C. R.; Convertino, V. A.

1986-01-01

The relationship between plasma aldosterone levels and sweat sodium excretion after chronic exercise and heat acclimation was investigated, using subjects exercised, at 40 C and 45 percent humidity, for 2 h/day on ten consecutive days at 45 percent of their maximal oxygen uptake. The data indicate that, following heat acclimation, plasma aldosterone concentrations decrease, and that the eccrine gland responsiveness to aldosterone, as represented by sweat sodium reabsorption, may be augmented through exercise and heat acclimation.

The physiological effects of dehydration caused by sweat loss. [athletes

NASA Technical Reports Server (NTRS)

Israel, S.

1981-01-01

The mechanisms of fluid loss in the human body while sweating due to physical exercise are discussed. Trained and untrained persons were examined and compared. Since sweat is hypotonous, a disruption in the hydrosalinic balance occurs; the consequences of this finding, also pertaining to the fluid and electrolytic substitution, are presented. Further explanations on the problem of dehydration refer to reactions of individual organ systems, to alterations in bodily capabilities as well as to questions relating to sex and age.

Babies and heat rashes

MedlinePlus

... occurs in babies when the pores of the sweat glands become blocked. This happens most often when ... weather is hot or humid. As your infant sweats, little red bumps, and possibly tiny blisters, form ...

Exercise clothing and shoes

MedlinePlus

... stay comfortable and dry, choose fabrics that pull sweat away from your skin and dry quickly. Many ... with special antimicrobial solutions to combat odor from sweat. Socks also come in quick-drying fabrics that ...

Effects of short-term exercise in the heat on thermoregulation, blood parameters, sweat secretion and sweat composition of tropic-dwelling subjects.

PubMed

Saat, Mohamed; Sirisinghe, Roland Gamini; Singh, Rabindarjeet; Tochihara, Yutaka

2005-09-01

This study investigates the effects of a short-term aerobic training program in a hot environment on thermoregulation, blood parameters, sweat secretion and composition in tropic-dwellers who have been exposed to passive heat. Sixteen healthy Malaysian-Malay male volunteers underwent heat acclimation (HA) by exercising on a bicycle ergometer at 60% of VO2max for 60 min each day in a hot environment (Ta: 31.1+/-0.1 degrees C, rh: 70.0+/-4.4%) for 14 days. All parameters mentioned above were recorded on Day 1 and at the end of HA (Day 16). On these two days, subjects rested for 10 min, then cycled at 60% of VO2max for 60 min and rested again for 20 min (recovery) in an improvised heat chamber. Rectal temperature (Tre), mean skin temperature (Tsk) heart rate (HR), ratings of perceived exertion (RPE), thermal sensation (TS), local sweat rate and percent dehydration were recorded during the test. Sweat concentration was analysed for sodium [Na+]sweat and potassium. Blood samples were analysed for biochemical changes, electrolytes and hematologic indices. Urine samples were collected before and after each test and analysed for electrolytes.After the period of acclimation the percent dehydration during exercise significantly increased from 1.77+/-0.09% (Day 1) to 2.14+/-0.07% (Day 16). Resting levels of hemoglobin, hematocrit and red blood cells decreased significantly while [Na+]sweat increased significantly. For Tre and Tsk there were no differences at rest. Tre, HR, RPE, TS, plasma lactate concentration, hemoglobin and hematocrit at the 40th min of exercise were significantly lower after the period of acclimation but mean corpuscular hemoglobin and serum osmolality were significantly higher while no difference was seen in [Na+]sweat and Tsk. It can be concluded that tropic-dwelling subjects, although exposed to prolonged passive heat exposure, were not fully heat acclimatized. To achieve further HA, they should gradually expose themselves to exercise-heat stress in a hot environment.

Local versus whole-body sweating adaptations following 14 days of traditional heat acclimation.

PubMed

Poirier, Martin P; Gagnon, Daniel; Kenny, Glen P

2016-08-01

The purpose of this study was to examine if local changes in sweat rate following 14 days of heat acclimation reflect those that occur at the whole-body level. Both prior to and following a 14-day traditional heat acclimation protocol, 10 males exercised in the heat (35 °C, ∼20% relative humidity) at increasing rates of heat production equal to 300 (Ex1), 350 (Ex2), and 400 (Ex3) W·m(-2). A 10-min recovery period followed Ex1, while a 20-min recovery period separated Ex2 and Ex3. The exercise protocol was performed in a direct calorimeter to measure whole-body sweat rate and, on a separate day, in a thermal chamber to measure local sweat rate (LSR), sweat gland activation (SGA), and sweat gland output (SGO) on the upper back, chest, and mid-anterior forearm. Post-acclimation, whole-body sweat rate was greater during each exercise bout (Ex1: 14.3 ± 0.9; Ex2: 17.3 ± 1.2; Ex3: 19.4 ± 1.3 g·min(-1), all p ≤ 0.05) relative to pre-acclimation (Ex1: 13.1 ± 0.6; Ex2: 15.4 ± 0.8; Ex3: 16.5 ± 1.3 g·min(-1)). In contrast, only LSR on the forearm increased with acclimation, and this increase was only observed during Ex2 (Post: 1.32 ± 0.33 vs. Pre: 1.06 ± 0.22 mg·min(-1)·cm(-2), p = 0.03) and Ex3 (Post: 1.47 ± 0.41 vs. Pre: 1.17 ± 0.23 mg·min(-1)·cm(-2), p = 0.05). The greater forearm LSR post-acclimation was due to an increase in SGO, as no changes in SGA were observed. Overall, these data demonstrate marked regional variability in the effect of heat acclimation on LSR, such that not all local measurements of sweat rate reflect the improvements observed at the whole-body level.

24 CFR 572.220 - Implementation grants-matching requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... be counted toward the match. (6) Donated labor. All donated labor, including sweat equity provided by..., electricians, carpenters, and architects that is equivalent to work they do in their occupations. Sweat equity...

How to avoid overheating during exercise

MedlinePlus

... is always working to maintain a safe temperature. Sweating helps your body cool down. When you exercise ... your muscles. This increases your heart rate. You sweat a lot, losing fluids in your body. If ...

40 CFR 63.1500 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Each new and existing group 2 furnace; (5) Each new and existing sweat furnace; (6) Each new and... scrap dryer/delacquering kiln/decoating kiln; (3) Each new and existing sweat furnace; (4) Each new and...

24 CFR 572.220 - Implementation grants-matching requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... be counted toward the match. (6) Donated labor. All donated labor, including sweat equity provided by..., electricians, carpenters, and architects that is equivalent to work they do in their occupations. Sweat equity...

24 CFR 572.220 - Implementation grants-matching requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... be counted toward the match. (6) Donated labor. All donated labor, including sweat equity provided by..., electricians, carpenters, and architects that is equivalent to work they do in their occupations. Sweat equity...

40 CFR 63.1500 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Each new and existing group 2 furnace; (5) Each new and existing sweat furnace; (6) Each new and... scrap dryer/delacquering kiln/decoating kiln; (3) Each new and existing sweat furnace; (4) Each new and...

24 CFR 572.220 - Implementation grants-matching requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... be counted toward the match. (6) Donated labor. All donated labor, including sweat equity provided by..., electricians, carpenters, and architects that is equivalent to work they do in their occupations. Sweat equity...

40 CFR 63.1500 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Each new and existing group 2 furnace; (5) Each new and existing sweat furnace; (6) Each new and... scrap dryer/delacquering kiln/decoating kiln; (3) Each new and existing sweat furnace; (4) Each new and...

24 CFR 572.220 - Implementation grants-matching requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... be counted toward the match. (6) Donated labor. All donated labor, including sweat equity provided by..., electricians, carpenters, and architects that is equivalent to work they do in their occupations. Sweat equity...

40 CFR 63.1500 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Each new and existing group 2 furnace; (5) Each new and existing sweat furnace; (6) Each new and... scrap dryer/delacquering kiln/decoating kiln; (3) Each new and existing sweat furnace; (4) Each new and...

40 CFR 63.1500 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Each new and existing group 2 furnace; (5) Each new and existing sweat furnace; (6) Each new and... scrap dryer/delacquering kiln/decoating kiln; (3) Each new and existing sweat furnace; (4) Each new and...

Treatment of TNT red water by layer melt crystallization.

PubMed

Jo, Jeong-Hyeon; Ernest, Takyi; Kim, Kwang-Joo

2014-09-15

Treatment of the red water, which is wastewater of 2,4,6- trinitrotoluene (TNT) manufacturing process has been explored using ice crystallization. This study focuses on the formation of ice crystals from the red water in a layer crystallizer under various operating conditions. Among the parameters which affect layer crystallization, attention was given to cooling rate, cooling temperature, sweating rate and concentration of the red water. The study highlights the effect of subcooling and growth rate on purity of the ice crystalline layers produced. After sweating, the COD value of crystalline ice layer was significantly reduced from 10,000 mg/L to below 20mg/L. Most organic contaminants were removed in sweating fractions of 0.5. Eventually, the red water was treated by layer crystallization combined with the sweating process. Copyright © 2014 Elsevier B.V. All rights reserved.

Incidence, severity, and impact of hyperhidrosis in people with lower-limb amputation.

PubMed

Hansen, Colby; Godfrey, Bradeigh; Wixom, Jody; McFadden, Molly

2015-01-01

To assess the incidence and severity of self-reported hyperhidrosis in patients with amputation and understand its effects on prosthetic fit or function, a cross-sectional survey of patients at two amputee clinics was performed. Responses from 121 subjects with lower-limb amputation were analyzed. Of these subjects, 66% reported sweating to a degree that it interfered with daily activities, as measured by the Hyperhidrosis Disease Severity Scale. There was a significant association between sweating and interference with prosthetic fit and function. Sweating was more severe in cases of transtibial amputations, patients under the age of 60, warm weather, and vigorous activity. There was no relationship between severity of sweating and time since amputation, etiology of amputation, duration of daily prosthetic use, or reported ability to perform functional tasks. Subjects reported trying multiple interventions, but the self-reported effectiveness of these treatments was low. Hyperhidrosis, a common problem associated with prosthetic usage, varies in severity and often interferes with daily activities. Sweating severity is associated with poor prosthetic fit and function. Risk factors include younger age and transtibial amputation status. Treatment strategies generally lack efficacy. The results of this study may provide guidance for future interventions and treatment options.

Dependence of palmar sweating response and central nervous system activity on the frequency of whole-body vibration.

PubMed

Ando, Hideo; Noguchi, Ryo

2003-06-01

This study was carried out to determine the effects of the frequency of whole-body vibration on palmar sweating response and the activity of the central sympathetic nervous system. Palmar sweating volume was measured on the right palm of six healthy men before and during 3 minutes of exposure to sinusoidal whole-body vibration at three different frequencies (16, 31.5, and 63 Hz). The whole-body vibration had a frequency-weighted, root mean square (rms) acceleration magnitude of 2.0 m/s2. As the index of the activated central sympathetic nervous system, saliva level of 3-methoxy-4-hydroxyphenylglycol (MHPG) was analyzed before and immediately after each vibration exposure. Each vibration frequency induced a palmar sweating response, that of 31.5 Hz being the largest. However, no significant difference was found between the three vibration conditions. Saliva MHPG increased in all the vibration exposures, and the largest change was observed at 31.5 Hz, the difference being significant. Acute exposure to whole-body vibration induced a palmar sweating response and activated the central sympathetic nervous system. The effects on the central nervous system were found to be dependent on the frequency of the vibration.

Pacing-induced palmar sweating evaluated by unique hygrometer: possible implications of sympathetic activation during tachycardia.

PubMed

Maruyama, T; Yanaga, T; Makino, N

2000-03-01

Although reflex sympathetic activation is a major determinant of the haemodynamic tolerability of ventricular tachycardia (VT), the methods for evaluating this aspect during on-going VT remain invasive and complicated. Palmar sweating as an indirect but non-invasive measure of sympathetic activity was estimated by means of a unique hygrometer under right ventricular (RV) rapid pacing (up to 150 beats min-1) replicating VT, and concurrent monitoring of aortic blood pressure in five patients with various kinds of cardiac arrhythmias in our electrophysiological laboratory. The peak palmar sweating rate in arbitrary units was augmented as the RV pacing rate increased and was proportional to the pacing-induced fall in systolic blood pressure (SBP), with a correlation coefficient of more than 0.903 (P<0.006). The slope of linearity between the sweating rate and the fall in SBP varied among individual patients, with greater sweating amplitude in the younger patients even with the same extent of fall in SBP. This preliminary study suggests sympathetic acceleration caused by haemodynamic deterioration under simulated VT, and therefore this protocol may be able to predict the haemodynamic tolerability of sustained monomorphic VT.

Human eccrine sweat gland cells reconstitute polarized spheroids when subcutaneously implanted with Matrigel in nude mice.

PubMed

Li, Haihong; Zhang, Mingjun; Chen, Liyun; Li, Xuexue; Zhang, Bingna

2016-10-01

Increasing evidence indicates that maintenance of cell polarity plays a pivotal role in the regulation of glandular homeostasis and function. We examine the markers for polarity at different time points to investigate the formation of cell polarity during 3D reconstitution of eccrine sweat glands. Mixtures of eccrine sweat gland cells and Matrigel were injected subcutaneously into the inguinal regions of nude mice. At 2, 3, 4, 5 and 6 weeks post-implantation, Matrigel plugs were removed and immunostained for basal collagen IV, lateral β-catenin, lateroapical ZO-1 and apical F-actin. The results showed that the cell polarity of the spheroids appeared in sequence. Formation of basal polarity was prior to lateral, apical and lateroapical polarity. Collagen IV was detected basally at 2 weeks, β-catenin laterally and ZO-1 lateroapically at 3 weeks, and F-actin apically at 4 weeks post-implantation. At week 5 and week 6, the localization and the positive percentage of collagen IV, β-catenin, ZO-1 or F-actin in spheroids was similar to that in native eccrine sweat glands. We conclude that the reconstituted 3D eccrine sweat glands are functional or potentially functional.

10 CFR 429.14 - Residential refrigerators, refrigerator-freezers and freezers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... anti-sweat heater control (in which case, manufacturers must also report the values of heater Watts at the ten humidity levels 5%, 15%, through 95% used to calculate the variable anti-sweat heater...

10 CFR 429.14 - Residential refrigerators, refrigerator-freezers and freezers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... anti-sweat heater control (in which case, manufacturers must also report the values of heater Watts at the ten humidity levels 5%, 15%, through 95% used to calculate the variable anti-sweat heater...

10 CFR 429.14 - Residential refrigerators, refrigerator-freezers and freezers.

Code of Federal Regulations, 2013 CFR

2013-01-01

... anti-sweat heater control (in which case, manufacturers must also report the values of heater Watts at the ten humidity levels 5%, 15%, through 95% used to calculate the variable anti-sweat heater...

Sweating

MedlinePlus

... the autonomic nervous system. This is the part of the nervous system that is not under your control. Sweating is ... Skin layers References Chelimsky T, Chelimsky G. Disorders of the autonomic nervous system. In: Daroff RB, Jankovic J, Mazziotta JC, Pomeroy ...

Smartphone chloridometer for point-of-care applications

NASA Astrophysics Data System (ADS)

Zhang, Chenji; Kim, Jimin P.; Creer, Michael; Yang, Jian; Liu, Zhiwen

2017-08-01

Chloride level in sweat is a major diagnostic criterion for cystic fibrosis (CF) and many other health conditions. In an effort to develop a low cost, point-of-care sweat diagnostics system for chloride concentration measurement, we demonstrated a smartphone-based chloridometer to measure sweat chloride by using our recently developed fluorescence chloride sensor. We characterized the performance of our device to validate its clinical potential. The study indicates that our smartphone-based chloridometer may potentially advance the point-of-care diagnostic system by reducing cost and improving diagnostic accuracy.

Use of an electrical resistance hygrometer to measure human sweat rates

NASA Technical Reports Server (NTRS)

Suga, T.

1980-01-01

The application of the resistance hygrometer as a tool to measure the localized sweat rate from the human body in both the active and passive sweat regions was studied. It was found that the physiological function of the skin membrane and fluid carrier transport phenomena from the outer skin have an indistinguishable effect on the observed findings from the instrument. The problems associated with the resistance hygrometer technique are identified and the usage of the instrument in the physiological experimentation from the engineering standpoint is evaluated.

Residual Limb Hyperhidrosis and RimabotulinumtoxinB: A Randomized Placebo-Controlled Study.

PubMed

Pasquina, Paul F; Perry, Briana N; Alphonso, Aimee L; Finn, Sacha; Fitzpatrick, Kevin F; Tsao, Jack W

2016-05-01

To investigate the use of rimabotulinumtoxinB (BoNT/B [Myobloc]) compared with placebo in treating hyperhidrosis in the residual limbs of individuals with amputation. Randomized, double-blind, placebo-controlled pilot study. Military medical center. Male participants (N=9) with 11 major amputations of the lower limbs and who complained of excessive sweating in their residual limbs were enrolled in the study between September 24, 2008 to October 28, 2011. Participants' lower limbs were randomly assigned to receive injections of either BoNT/B (n=7) or placebo (n=4). BoNT/B. The primary efficacy variable was a minimum of 50% reduction in sweat production 4 weeks after the injection as measured via gravimetric sweat analysis after 10 minutes of physical exertion. Secondary analyses were performed on prosthetic function and pain. All volunteers (100%; 7) in the BoNT/B group achieved a minimum of 50% reduction in sweat production as compared with only 50% (2) in the placebo group. The percent reduction was significantly greater for the BoNT/B group than for the placebo group (-72.7%±15.7% vs -32.7%±39.2%; P<.05). Although both groups subjectively self-reported significant sweat reduction and improved prosthetic function (P<.05 for both), objective gravimetric sweat analyses significantly decreased only for the BoNT/B group (2.3±2.3g vs 0.7±1.1g; P<.05). Neither group reported a change in phantom limb pain or residual limb pain (P>.05 for both). BoNT/B successfully reduces sweat production in individuals with residual limb hyperhidrosis, but does not affect pain. No differences were found in perceived effect on prosthetic use between BoNT/B and placebo groups. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Long-term results of endoscopic sympathetic block using the Lin-Telaranta classification.

PubMed

Rantanen, Tuomo; Telaranta, Timo

2013-10-01

Endoscopic thoracic sympathectomy has been used successfully in the treatment of blushing, excessive sweating, and social phobia. However, the adverse effects of endoscopic thoracic sympathectomy are more severe and frequent than the adverse effects of endoscopic sympathetic block (ESB). The use of different blocking levels for different indications in ESB according to the Lin-Telaranta classification further decreases the postoperative adverse effects. However, there are few data on the long-term results of ESB performed using the Lin-Telaranta classification. Ninety-five patients (55 men, 40 women) were interviewed by before the surgery using our routine questionnaire, and the same questionnaire was answered postoperatively by the patients. In addition, a long-term follow-up questionnaire was sent to all patients whose address was known. Forty-seven patients (24 men, 23 women) answered to this questionnaire. The Davidson brief social phobia scale and the Liebowitz quality of life scale were used. Patients were divided to 3 categories: category 1, patients with sweating problems; category 2, patients with blushing; and category 3, and patients with symptoms other than sweating or blushing. Among patients in category 1, social phobia decreased from 12.43 to 6.71 (p = 0.004), in category 2 from 13.97 to 7.69 (p < 0.001), and in category 3 from 13.18 to 9.64 (p = 0.007) during long-term follow-up. Among patients with severe sweating problems preoperatively, sweating decreased from 2.50 to 1.29 (p = 0.003) among patients in category 1 and from 1.86 to 1.16 (p < 0.001) among patients in category 2. Among patients with unbearable blushing, blushing decreased from 4 to 1.80 (p < 0.001). Patients got a clear help from ESB performed using the Lin-Telaranta classification to treat blushing, excessive sweating, and social phobia with and without physical symptoms. In addition, compensatory sweating increased only slightly.

Altered olfactory processing of stress-related body odors and artificial odors in patients with panic disorder.

PubMed

Wintermann, Gloria-Beatrice; Donix, Markus; Joraschky, Peter; Gerber, Johannes; Petrowski, Katja

2013-01-01

Patients with Panic Disorder (PD) direct their attention towards potential threat, followed by panic attacks, and increased sweat production. Onés own anxiety sweat odor influences the attentional focus, and discrimination of threat or non-threat. Since olfactory projection areas overlap with neuronal areas of a panic-specific fear network, the present study investigated the neuronal processing of odors in general and of stress-related sweat odors in particular in patients with PD. A sample of 13 patients with PD with/ without agoraphobia and 13 age- and gender-matched healthy controls underwent an fMRI investigation during olfactory stimulation with their stress-related sweat odors (TSST, ergometry) as well as artificial odors (peach, artificial sweat) as non-fearful non-body odors. The two groups did not differ with respect to their olfactory identification ability. Independent of the kind of odor, the patients with PD showed activations in fronto-cortical areas in contrast to the healthy controls who showed activations in olfaction-related areas such as the amygdalae and the hippocampus. For artificial odors, the patients with PD showed a decreased neuronal activation of the thalamus, the posterior cingulate cortex and the anterior cingulate cortex. Under the presentation of sweat odor caused by ergometric exercise, the patients with PD showed an increased activation in the superior temporal gyrus, the supramarginal gyrus, and the cingulate cortex which was positively correlated with the severity of the psychopathology. For the sweat odor from the anxiety condition, the patients with PD showed an increased activation in the gyrus frontalis inferior, which was positively correlated with the severity of the psychopathology. The results suggest altered neuronal processing of olfactory stimuli in PD. Both artificial odors and stress-related body odors activate specific parts of a fear-network which is associated with an increased severity of the psychopathology.

Evidence for cyclooxygenase-dependent sweating in young males during intermittent exercise in the heat

PubMed Central

Fujii, Naoto; McGinn, Ryan; Stapleton, Jill M; Paull, Gabrielle; Meade, Robert D; Kenny, Glen P

2014-01-01

Our recent work implicated nitric oxide (NO) in the control of sweating during intermittent exercise; however, it is unclear if cyclooxygenase (COX) is also involved. On separate days, ten healthy young (24 ± 4 years) males cycled in the heat (35°C). Two 30 min exercise bouts were performed at either a moderate (400 W, moderate heat load) or high (700 W, high heat load) rate of metabolic heat production and were followed by 20 and 40 min of recovery, respectively. Forearm sweating (ventilated capsule) was evaluated at four skin sites that were continuously perfused via intradermal microdialysis with: (1) lactated Ringer solution (Control), (2) 10 mm ketorolac (a non-selective COX inhibitor), (3) 10 mm NG-nitro-l-arginine methyl ester (l-NAME; a non-selective NO synthase inhibitor) or (4) a combination of 10 mm ketorolac + 10 mml-NAME. During the last 5 min of the first exercise at moderate heat load, forearm sweating (mg min−1 cm−2) was equivalently reduced with ketorolac (0.54 ± 0.08), l-NAME (0.55 ± 0.07) and ketorolac+l-NAME (0.56 ± 0.08) compared to Control (0.67 ± 0.06) (all P < 0.05). Similar results were obtained for the second exercise at moderate heat load (all P < 0.05). However, forearm sweating was similar between the four sites during exercise at high heat load and during recovery regardless of exercise intensity (all P > 0.05). We show that (1) although both COX and NO modulate forearm sweating during intermittent exercise bouts in the heat at a moderate heat load, the effects are not additive, and (2) the contribution of both enzymes to forearm sweating is less evident during intermittent exercise when the heat load is high and during recovery. PMID:25326453

An immortal cell line to study the role of endogenous CFTR in electrolyte absorption.

PubMed

Bell, C L; Quinton, P M

1995-01-01

The intact human reabsorptive sweat duct (RD) has been a reliable model for investigations of the functional role of "endogenous" CFTR (cystic fibrosis transmembrane conductance regulator) in normal and abnormal electrolyte absorptive function. But to overcome the limitations imposed by the use of fresh, intact tissue, we transformed cultured RD cells using the chimeric virus Ad5/SV40 1613 ori-. The resultant cell line, RD2(NL), has remained differentiated forming a polarized epithelium that expressed two fundamental components of absorption, a cAMP activated Cl- conductance (GCl) and an amiloride-sensitive Na+ conductance (GNa). In the unstimulated state, there was a low level of transport activity; however, addition of forskolin (10(-5) M) significantly increased the Cl- diffusion potential (Vt) generated by a luminally directed Cl- gradient from -15.3 +/- 0.7 mV to -23.9 +/- 1.1 mV, n = 39; and decreased the transepithelial resistance (Rt) from 814.8 +/- 56.3 omega.cm2 to 750.5 +/- 47.5 omega.cm2, n = 39, (n = number of cultures). cAMP activation, anion selectivity (Cl- > I- > gluconate), and a dependence upon metabolic energy (metabolic poisoning inhibited GCl), all indicate that the GCl expressed in RD2(NL) is in fact CFTR-GCl. The presence of an apical amiloride-sensitive GNa was shown by the amiloride (10(-5) M) inhibition of GNa as indicated by a reduction of Vt and equivalent short circuit current by 78.0 +/- 3.1% and 77.9 +/- 2.6%, respectively, and an increase in Rt by 7.2 +/- 0.8%, n = 36. In conclusion, the RD2(NL) cell line presents the first model system in which CFTR-GCl is expressed in a purely absorptive tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

C-reactive protein as a screening test for HIV-associated pulmonary tuberculosis prior to antiretroviral therapy in South Africa.

PubMed

Shapiro, Adrienne E; Hong, Ting; Govere, Sabina; Thulare, Hilary; Moosa, Mahomed-Yunus; Dorasamy, Afton; Wallis, Carole L; Celum, Connie L; Grosset, Jacques; Drain, Paul K

2018-05-28

There is an urgent need for more accurate screening tests for tuberculosis(TB). We assessed the diagnostic accuracy of C-reactive protein (CRP) as a screening test for active TB in HIV-infected ambulatory adults. CRP levels were measured in blood collected at the time of HIV testing.Diagnostic accuracy of CRP for pulmonary TB was calculated (reference standard: TB culture), compared to the WHO 4-symptom screen, consisting of cough, fever, night sweats, and weight loss. Diagnostic accuracy was also calculated for CRP in a larger cohort of HIV-infected adults with a positive symptom screen (reference standard: clinical or microbiological TB). Among 425 HIV-infected outpatients systematically tested for pulmonary TB, TB culture was positive in 42 (10%), 279 (66%) had at least one TB-related symptom and 197 (46%) had a CRP >5 mg/L. The sensitivity of CRP and the TB symptom screen to detect TB was the same (90.5%; 95%CI 77.4-97.3) but specificity of CRP was higher than for the TB symptom screen (58.5% vs. 37.1%, p<0.001). Of persons with no symptoms and normal CRP, 99 (98%) had no TB. In another cohort of 749 patients presenting with at least one TB-related symptom and clinically evaluated, CRP had a sensitivity of 98.7% and specificity of 48.3%. In HIV-infected outpatients, CRP was as sensitive but substantially more specific than TB symptom screening. Use of CRP as a screening tool to exclude active TB could identify the same number of HIV-associated TB cases, but reduce the use of diagnostic sputum testing in TB-endemic regions.

24 CFR 92.220 - Form of matching contribution.

Code of Federal Regulations, 2011 CFR

2011-04-01

... sweat equity (see § 92.354(c)) provided to a homeownership project, under an established component of a... (a)(8) of this section or to persons contributing sweat equity in accordance with paragraph (a)(9) of...

24 CFR 92.220 - Form of matching contribution.

Code of Federal Regulations, 2014 CFR

2014-04-01

... sweat equity (see § 92.354(c)) provided to a homeownership project, under an established component of a... (a)(8) of this section or to persons contributing sweat equity in accordance with paragraph (a)(9) of...

76 FR 77548 - Notice of Submission of Proposed Information Collection to OMB Self-Help Homeownership...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-13

... sweat equity and volunteer-based homeownership programs for low-income persons and families. This... infrastructure to support sweat equity and volunteer-based homeownership programs for low-income persons and...

24 CFR 92.220 - Form of matching contribution.

Code of Federal Regulations, 2013 CFR

2013-04-01

... sweat equity (see § 92.354(c)) provided to a homeownership project, under an established component of a... (a)(8) of this section or to persons contributing sweat equity in accordance with paragraph (a)(9) of...

24 CFR 92.220 - Form of matching contribution.

Code of Federal Regulations, 2012 CFR

2012-04-01

... sweat equity (see § 92.354(c)) provided to a homeownership project, under an established component of a... (a)(8) of this section or to persons contributing sweat equity in accordance with paragraph (a)(9) of...

24 CFR 92.220 - Form of matching contribution.

Code of Federal Regulations, 2010 CFR

2010-04-01

... sweat equity (see § 92.354(c)) provided to a homeownership project, under an established component of a... (a)(8) of this section or to persons contributing sweat equity in accordance with paragraph (a)(9) of...

Evaporative water loss in man in a gravity-free environment

NASA Technical Reports Server (NTRS)

Leach, C. S.; Leonard, J. I.; Rambaut, P. C.; Johnson, P. C.

1978-01-01

Daily evaporative water losses (EWL) during the three Skylab missions were measured indirectly using mass and water-balance techniques. The mean daily values of EWL for the nine crew members who averaged 1 hr of daily exercise were: preflight 1,750 + or - 37 (SE) ml or 970 + or - 20 ml/sq m and inflight 1,560 + or - 26 ml or 860 + or - 14 ml/sq m. Although it was expected the EWL would increase in the hypobaric environment of Skylab, an average decrease from preflight sea-level conditions of 11% was measured. The results suggest that weightlessness decreased sweat losses during exercise and possibly reduced insensible skin losses. The weightlessness environment apparently promotes the formation of an observed sweat film on the skin surface during exercise by reducing convective flow and sweat drippage, resulting in high levels of skin wettedness that favor sweat suppression.

Physiological strain of miners at hot working places in German coal mines.

PubMed

Kalkowsky, Bernhard; Kampmann, Bernhard

2006-07-01

As the percentage of shifts in hot working conditions in German Coal mines had increased to more than 50% during the last decade, a study was carried out to record the physiological strain of miners. Thirty-eight miners participated during 125 shifts. Heart rate and rectal temperature were measured continuously. Sweat losses as well as food and fluid uptake were estimated from measurements before and after shifts. During all shifts mean heart rates resulted in 102.8 min(-1), mean rectal temperature was 37.7 degrees C. Mean sweat loss per shift was 3,436 g; mean sweat rates resulted in 494 g/h. Rehydration during the shift at high climatic stress decreased to about 60% of sweat losses. In order to state the organizational frame of work at hot working places in German coal mines, the main features of regulations of work at hot working places are presented.

Hot flushes and night sweats symptom profiles over a 17-year period in mid-aged women: The role of hysterectomy with ovarian conservation.

PubMed

Wilson, Louise F; Pandeya, Nirmala; Byles, Julie; Mishra, Gita D

2016-09-01

There is limited research on hot flushes and night sweats in women with a hysterectomy with ovarian conservation. We aimed to describe the patterns of these symptoms in a cohort of Australian women and to investigate the relationship between distinct symptom patterns and hysterectomy status. Repeated-measures latent class analysis (LCA) was used to identify hot flushes and night sweats symptom patterns across seven surveys (over 17 years) in the mid-cohort of the Australian Longitudinal Study on Women's Health. Multinomial logistic regression was used to assess the associations of the symptom patterns in women with a hysterectomy with ovarian conservation (n=1129) versus women without a hysterectomy (n=4977). A higher proportion of women with a hysterectomy than of those without experienced a constant pattern of hot flushes (15% versus 30%) and night sweats (9% versus 19%). Women with a hysterectomy had higher odds of constant hot flushes versus minimal hot flushes (OR=1.97, 95% CI: 1.64, 2.35) and constant versus minimal night sweats (OR=2.09, 95% CI: 1.70, 2.55). Smoking, a 'lower level of education to non-professional occupation' pathway and body mass index (BMI) patterns of 'always obese' and 'increasingly obese' were also associated with a higher risk of constant symptoms. Women who have a hysterectomy (with ovarian conservation) have a higher risk of hot flushes and night sweats that persist over an extended period. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Study of sample preparation for quantitative analysis of amino acids in human sweat by liquid chromatography-tandem mass spectrometry.

PubMed

Delgado-Povedano, M M; Calderón-Santiago, M; Priego-Capote, F; Luque de Castro, M D

2016-01-01

The determination of physiological levels of amino acids is important to aid in the diagnosis and treatment of several diseases and nutritional status of individuals. Amino acids are frequently determined in biofluids such as blood (serum or plasma) and urine; however, there are less common biofluids with different concentration profiles of amino acids that could be of interest. One of these biofluids is sweat that can be obtained in a non-invasive manner and is characterized by low complex composition. The analysis of amino acids in human sweat requires the development of sample preparation strategies according to the sample matrix and small collected volume. The influence of sample preparation on the quantitative analysis of amino acids in sweat by LC-MS/MS has been assessed through a comparison between two strategies: dilution of sweat and centrifugal microsolid-phase extraction (c-μSPE). In both cases, several dilution factors were assayed for in-depth knowledge of the matrix effects, and the use of c-μSPE provided the best results in terms of accuracy. The behavior of the target analytes was a function of the dilution factor, thus providing a pattern for sample preparation that depended on the amino acid to be determined. The concentration of amino acids in sweat ranges between 6.20 ng mL(-1) (for homocysteine) and 259.77 µg mL(-1) (for serine) with precision, expressed as relative standard deviation, within 1.1-21.4%. Copyright © 2015 Elsevier B.V. All rights reserved.

Soft, skin-mounted microfluidic systems for measuring secretory fluidic pressures generated at the surface of the skin by eccrine sweat glands.

PubMed

Choi, Jungil; Xue, Yeguang; Xia, Wei; Ray, Tyler R; Reeder, Jonathan T; Bandodkar, Amay J; Kang, Daeshik; Xu, Shuai; Huang, Yonggang; Rogers, John A

2017-07-25

During periods of activity, sweat glands produce pressures associated with osmotic effects to drive liquid to the surface of the skin. The magnitudes of these pressures may provide insights into physiological health, the intensity of physical exertion, psychological stress factors and/other information of interest, yet they are currently unknown due to absence of means for non-invasive measurement. This paper introduces a thin, soft wearable microfluidic system that mounts onto the surface of the skin to enable precise and routine measurements of secretory fluidic pressures generated at the surface of the skin by eccrine sweat glands (surface SPSG, or s-SPSG) at nearly any location on the body. These platforms incorporate an arrayed collection of unit cells each of which includes an opening to the skin, an inlet through which sweat can flow, a capillary bursting valve (CBV) with a unique bursting pressure (BP), a corresponding microreservoir to receive sweat and an outlet to the surrounding ambient to allow release of backpressure. The BPs systematically span the physiologically relevant range, to enable a measurement precision approximately defined by the ratio of the range to the number of unit cells. Human studies demonstrate measurements of s-SPSG under different conditions, from various regions of the body. Average values in healthy young adults lie between 2.4 and 2.9 kPa. Sweat associated with vigorous exercise have s-SPSGs that are somewhat higher than those associated with sedentary activity. For all conditions, the forearm and lower back tend to yield the highest and lowest s-SPSGs, respectively.

Outdoor thermal physiology along human pathways: a study using a wearable measurement system

NASA Astrophysics Data System (ADS)

Nakayoshi, Makoto; Kanda, Manabu; Shi, Rui; de Dear, Richard

2015-05-01

An outdoor summer study on thermal physiology along subjects' pathways was conducted in a Japanese city using a unique wearable measurement system that measures all the relevant thermal variables: ambient temperature, humidity, wind speed ( U) and short/long-wave radiation ( S and L), along with some physio-psychological parameters: skin temperature ( T skin), pulse rate, subjective thermal sensation and state of body motion. U, S and L were measured using a globe anemo-radiometer adapted use with pedestrian subjects. The subjects were 26 healthy Japanese adults (14 males, 12 females) ranging from 23 to 74 years in age. Each subject wore a set of instruments that recorded individual microclimate and physiological responses along a designated pedestrian route that traversed various urban textures. The subjects experienced varying thermal environments that could not be represented by fixed-point routine observational data. S fluctuated significantly reflecting the mixture of sunlit/shade distributions within complex urban morphology. U was generally low within urban canyons due to drag by urban obstacles such as buildings but the subjects' movements enhanced convective heat exchanges with the atmosphere, leading to a drop in T skin. The amount of sweating increased as standard effective temperature (SET*) increased. A clear dependence of sweating on gender and body size was found; males sweated more than females; overweight subjects sweated more than standard/underweight subjects. T skin had a linear relationship with SET* and a similarly clear dependence on gender and body size differences. T skin of the higher-sweating groups was lower than that of the lower-sweating groups, reflecting differences in evaporative cooling by perspiration.

Contemporary biological markers of exposure to fluoride.

PubMed

Rugg-Gunn, Andrew John; Villa, Alberto Enrique; Buzalaf, Marília Rabelo Afonso

2011-01-01

Contemporary biological markers assess present, or very recent, exposure to fluoride: fluoride concentrations in blood, bone surface, saliva, milk, sweat and urine have been considered. A number of studies relating fluoride concentration in plasma to fluoride dose have been published, but at present there are insufficient data on plasma fluoride concentrations across various age groups to determine the 'usual' concentrations. Although bone contains 99% of the body burden of fluoride, attention has focused on the bone surface as a potential marker of contemporary fluoride exposure. From rather limited data, the ratio surface-to-interior concentration of fluoride may be preferred to whole bone fluoride concentration. Fluoride concentrations in the parotid and submandibular/sublingual ductal saliva follow the plasma fluoride concentration, although at a lower concentration. At present, there are insufficient data to establish a normal range of fluoride concentrations in ductal saliva as a basis for recommending saliva as a marker of fluoride exposure. Sweat and human milk are unsuitable as markers of fluoride exposure. A proportion of ingested fluoride is excreted in urine. Plots of daily urinary fluoride excretion against total daily fluoride intake suggest that daily urinary fluoride excretion is suitable for predicting fluoride intake for groups of people, but not for individuals. While fluoride concentrations in plasma, saliva and urine have some ability to predict fluoride exposure, present data are insufficient to recommend utilizing fluoride concentrations in these body fluids as biomarkers of contemporary fluoride exposure for individuals. Daily fluoride excretion in urine can be considered a useful biomarker of contemporary fluoride exposure for groups of people, and normal values have been published. Copyright © 2011 S. Karger AG, Basel.

Myelofibrosis

MedlinePlus

... spleen Easy bruising Easy bleeding Excessive sweating during sleep (night sweats) Fever Bone pain When to see a doctor Make an appointment with your doctor if you have any persistent signs and symptoms that worry you. Causes Myelofibrosis occurs when blood stem cells develop a ...

77 FR 40892 - Announcement of Funding Awards for the Self-Help Homeownership Opportunity Program (SHOP) for...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-11

... must contribute their sweat equity to the construction of their homes and/or the homes of other homebuyers. Reasonable accommodations are made for homebuyers with disabilities. Sweat equity involves... [[Page 40893

Parents' and Coaches' Guide to Dehydration and Other Heat Illnesses in Children

MedlinePlus

... illnesses can be prevented and successfully treated. Children sweat less than adults. This makes it harder for ... they do not replace body fluids lost by sweating. Being even a little dehydrated can make a ...

Mineral Losses During Extreme Environmental Conditions

USDA-ARS?s Scientific Manuscript database

Advisory groups that make recommendations for mineral intakes continue to identify accurate determinations of sweat mineral losses during physical activity as a critical void in their deliberations. Although estimates of sweat mineral concentrations are available, they are highly variable. Practica...

Sweating is greater in NCAA football linemen independently of heat production.

PubMed

Deren, Tomasz M; Coris, Eric E; Bain, Anthony R; Walz, Steve M; Jay, Ollie

2012-02-01

The study's purpose was to investigate whether differences in local sweat rates on the upper body between American football linemen (L) and backs (B) exist independently of differences in metabolic heat production. Twelve NCAA Division I American football players (6 linemen (mass = 141.6 ± 6.5 kg, body surface area (BSA) = 2.67 ± 0.08 m2) and 6 backs (mass = 88.1 ± 13.4 kg, BSA = 2.11 ± 0.19 m2)) cycled at a fixed metabolic heat production per unit BSA of 350 W·m(-2) for 60 min in a climatic chamber (t(db) [dry bulb temperature] = 32.4°C ± 1.0°C, t(wb) [wet bulb temperature] = 26.3°C ± 0.6°C, v [air velocity] = 0.9 ± 0.1 m·s(-1)). Local sweat rates on the head, arm, shoulder, lower back, and chest were measured after 10, 30, and 50 min of exercise. Core temperature, mean skin temperature, and HR were measured throughout exercise. Because metabolic heat production per unit surface area was fixed between participants, the rate of evaporation required for heat balance was similar (L = 261 ± 35 W·m(-2), B = 294 ± 30 W·m(-2), P = 0.11). However, local sweat rates on the head, arm, shoulder, and chest were all significantly greater (P < 0.05) in linemen at all time points, and end-exercise core temperature was significantly greater (P = 0.033) in linemen (38.5°C ± 0.4°C) relative to backs (38.0°C ± 0.2°C) despite a ∼25% lower heat production per unit mass. The change in mean skin temperature from rest was greater in linemen (P < 0.001) after 15, 30, 45, and 60 min, and HR was greater in linemen for the last 30 min of exercise. Football linemen sweat significantly more on the torso and head than football backs independently of any differences in metabolic heat production per unit BSA and therefore the evaporative requirements for heat balance. Despite greater sweating, linemen demonstrated significantly greater elevations in core temperature suggesting that sweating efficiency (i.e., the proportion of sweat that evaporates) was much lower in linemen.

Fluid consumption and sweating in National Football League and collegiate football players with different access to fluids during practice.

PubMed

Godek, Sandra Fowkes; Bartolozzi, Arthur R; Peduzzi, Chris; Heinerichs, Scott; Garvin, Eugene; Sugarman, Eric; Burkholder, Richard

2010-01-01

Considerable controversy regarding fluid replacement during exercise currently exists. To compare fluid turnover between National Football League (NFL) players who have constant fluid access and collegiate football players who replace fluids during water breaks in practices. Observational study. Respective preseason training camps of 1 National Collegiate Athletic Association Division II (DII) football team and 1 NFL football team. Both morning and afternoon practices for DII players were 2.25 hours in length, and NFL players practiced for 2.25 hours in the morning and 1 hour in the afternoon. Environmental conditions did not differ. Eight NFL players (4 linemen, 4 backs) and 8 physically matched DII players (4 linemen, 4 backs) participated. All players drank fluids only from their predetermined individual containers. The NFL players could consume both water and sports drinks, and the DII players could only consume water. We measured fluid consumption, sweat rate, total sweat loss, and percentage of sweat loss replaced. Sweat rate was calculated as change in mass adjusted for fluids consumed and urine produced. Mean sweat rate was not different between NFL (2.1 +/- 0.25 L/h) and DII (1.8 +/- 0.15 L/h) players (F(1,12) = 2, P = .18) but was different between linemen (2.3 +/- 0.2 L/h) and backs (1.6 +/- 0.2 L/h) (t(14) = 3.14, P = .007). We found no differences between NFL and DII players in terms of percentage of weight loss (t(7) = -0.03, P = .98) or rate of fluid consumption (t(7) = -0.76, P = .47). Daily sweat loss was greater in DII (8.0 +/- 2.0 L) than in NFL (6.4 +/- 2.1 L) players (t(7) = -3, P = .02), and fluid consumed was also greater in DII (5.0 +/- 1.5 L) than in NFL (4.0 +/- 1.1 L) players (t(7) = -2.8, P = .026). We found a correlation between sweat loss and fluids consumed (r = 0.79, P < .001). During preseason practices, the DII players drinking water at water breaks replaced the same volume of fluid (66% of weight lost) as NFL players with constant access to both water and sports drinks.

A randomised controlled trial of a cognitive behavioural intervention for women who have menopausal symptoms following breast cancer treatment (MENOS 1): Trial protocol

PubMed Central

2011-01-01

Background This trial aims to evaluate the effectiveness of a group cognitive behavioural intervention to alleviate menopausal symptoms (hot flushes and night sweats) in women who have had breast cancer treatment. Hot flushes and night sweats are highly prevalent but challenging to treat in this population. Cognitive behaviour therapy has been found to reduce these symptoms in well women and results of an exploratory trial suggest that it might be effective for breast cancer patients. Two hypotheses are tested: Compared to usual care, group cognitive behavioural therapy will: 1. Significantly reduce the problem rating and frequency of hot flushes and nights sweats after six weeks of treatment and at six months post-randomisation. 2. Improve mood and quality of life after six weeks of treatment and at six months post-randomisation. Methods/Design Ninety-six women who have completed their main treatment for breast cancer and who have been experiencing problematic hot flushes and night sweats for over two months are recruited into the trial from oncology and breast clinics in South East London. They are randomised to either six weekly group cognitive behavioural therapy (Group CBT) sessions or to usual care. Group CBT includes information and discussion about hot flushes and night sweats in the context of breast cancer, monitoring and modifying precipitants, relaxation and paced respiration, stress management, cognitive therapy for unhelpful thoughts and beliefs, managing sleep and night sweats and maintaining changes. Prior to randomisation women attend a clinical interview, undergo 24-hour sternal skin conductance monitoring, and complete questionnaire measures of hot flushes and night sweats, mood, quality of life, hot flush beliefs and behaviours, optimism and somatic amplification. Post-treatment measures (sternal skin conductance and questionnaires) are collected six to eight weeks later and follow-up measures (questionnaires and a use of medical services measure) at six months post-randomisation. Discussion MENOS 1 is the first randomised controlled trial of cognitive behavioural therapy for hot flushes and night sweats that measures both self-reported and physiologically indexed symptoms. The results will inform future clinical practice by developing an evidence-based, non-medical treatment, which can be delivered by trained health professionals. Trial Registration Current Controlled Trials ISRCTN13771934 PMID:21281461