Effects of exposure to high temperatures on serum, urine and sweat concentrations of iron and copper.

The objective of this research was to determine the acute effect of a maximum test until exhaustion in normothermia and hyperthermia, and after repeated exposure to heat at high temperatures on the homeostasis of Fe and Cu. The sample was composed of twenty-nine male university students. The participants were divided into a control group (CG) and an experimental group (EG). All of them underwent an incremental test until exhaustion in normothermia and hyperthermia before and after the repeated exposure of EG to heat at high temperatures, consisting of 9 heat acclimatisation sessions in the sauna. Samples of urine and blood were taken before and after each test. Additionally, sweat samples were collected in the hyperthermia test. The samples were frozen at -80 °C for further analysis by ICP-MS. None of the metal concentrations in serum were affected by hyperthermia or exposure to heat. Urinary Fe increased in CG in the hyperthermia test before Heat exposure at High Temperature (HEHT)(p < 0.05) and in both groups after HEHT (p < 0.05). In EG there was an increase in the urinary excretion of Cu after HEHT (p < 0.01) in both trials. Fe suffered a decrease in sweat in EG after exposure to heat (p < 0.05). The concentrations of Fe and Cu in serum were not affected by acute exercise and exposure to high temperatures. However, there was a decrease in excretion of Fe in sweat due to HEHT, and an increase in urinary excretion in both. Therefore, we think that in conditions of high temperatures for long periods of time, attention should be paid to the body levels of these metals.

Effect of exposure to high temperatures in the excretion of cadmium and lead.

OBJECTIVE: This study aims to observe the effect on urine and sweat excretion levels of cadmium (Cd) and lead (Pb) in healthy men in a maximum incremental test until exhaustion and repeated exposure to heat. METHODS: twenty-nine adult men divided into control group (CG; n = 14) and experimental group (EG; n = 15) performing two maximum tests until exhaustion in normothermia (22 °C) and hyperthermia (42 °C). EG experienced 9 sessions of heat exposure at high temperatures (100 °C) (HEHT). After the nine sessions, the initial tests were repeated in both groups. Urine samples were collected before and after each test. After the hyperthermia tests, sweat samples were gathered. RESULTS: Urinary Cd increased after initial tests in GC and in hyperthermia in EG (p < 0.05). Urinary excretion of Pb rose after HEHT (p < 0.05). Pb in sweat was higher in EG than in CG after HEHT (p < 0.05). CONCLUSION: Heat exercise and constant exposure to heat can be a valid method to increase the excretion of toxic metals.

Urinary metabolites of the UV filter 2-Ethylhexyl salicylate as biomarkers of exposure in humans.

The UV filter 2-ethylhexyl salicylate (EHS) is used in sunscreens and other personal care products worldwide and has been found in a variety of environmental media. We aimed to provide human toxicokinetic data on EHS as a tool for risk assessment. For that purpose, we investigated metabolism and urinary metabolite excretion after a single oral EHS dose (57.4-75.5 µg/(kg body weight)) in three male volunteers. In a suspect screening, we tentatively identified seven EHS metabolites. Three EHS specific metabolites were quantitatively investigated: 2-ethyl-5-hydroxyhexyl 2-hydroxybenzoate (5OH-EHS), 2-ethyl-5-oxohexyl 2-hydroxybenzoate (5oxo-EHS), and 5-(((2-hydroxybenzoyl)oxy)methyl)heptanoic acid (5cx-EPS). These metabolites were excreted with urinary excretion fractions of 0.28% (range: 0.13-0.54%), 0.11% (0.06-0.20%), and 0.24% (0.14-0.41%), respectively. The elimination was fast: peak urinary concentrations were found 1.6-2.6 h after dose and ≥95% of the total amounts were excreted within 24 h. Elimination kinetics were biphasic, with mean elimination half-lives of 0.8 h (first phase) and 6.6 h (second phase) for 5OH-EHS, 0.8 h and 6.3 h for 5oxo-EHS, and 1.1 h and 5.9 h for 5cx-EPS. After dermal exposure (sunscreen application), we found a considerably delayed EHS elimination. Based on urinary metabolite levels we calculated EHS exposure levels for a small pilot population.

Air-breathing and excretory nitrogen metabolism in fishes.

During water-land transition, ancient fishes acquired the ability to breathe air, but air-breathing engendered problems in nitrogenous waste excretion. Nitrogen is a fundamental component of amino acids, proteins, and nucleic acids, and the degradation of these nitrogen-containing compounds releases ammonia. Ammonia is toxic and must be removed. Fishes in water excrete ammonia as the major nitrogenous waste through gills, but gills of air-breathing fishes are modified for air-breathing or largely replaced by air-breathing organs. Notably, fishes emerged from water can no longer excrete ammonia effectively because of a lack of water to flush the gills. Hence, ancient fishes that participated in water-land transition must have developed means to deal with ammonia toxicity. Extant air-breathing fishes, particularly amphibious ones, can serve as models to examine adaptations which might have facilitated the emergence of ancient fishes from water. Some of these fishes can actively emerge from water and display complex behaviors on land, while a few can burrow into mud and survive for years during drought. Many of them are equipped with mechanisms to ameliorate ammonia toxicity during emersion. In this review, the mechanisms adopted by air-breathing fishes to deal with ammonia toxicity during emersion were organized into seven disparate strategies. In addition, eight extant air-breathing fishes with distinctive terrestrial behaviors and peculiar natural habitats were selected to describe in detail how these seven strategies could be adopted in disparate combinations to ameliorate ammonia toxicity during emersion.

Widespread use of emersion and cutaneous ammonia excretion in Aplocheiloid killifishes.

The invasion of land required amphibious fishes to evolve new strategies to avoid toxic ammonia accumulation in the absence of water flow over the gills. We investigated amphibious behaviour and nitrogen excretion strategies in six phylogenetically diverse Aplocheiloid killifishes (Anablepsoides hartii, Cynodonichthys hildebrandi, Rivulus cylindraceus, Kryptolebias marmoratus, Fundulopanchax gardneri, and Aplocheilus lineatus) in order to determine if a common strategy evolved. All species voluntarily emersed (left water) over several days, and also in response to environmental stressors (low O2, high temperature). All species were ammoniotelic in water and released gaseous ammonia (NH3 volatilization) during air exposure as the primary route for nitrogen excretion. Metabolic depression, urea synthesis, and/or ammonia accumulation during air exposure were not common strategies used by these species. Immunostaining revealed the presence of ammonia-transporting Rhesus proteins (Rhcg1 and Rhcg2) in the skin of all six species, indicating a shared mechanism for ammonia volatilization. We also found Rhcg in the skin of several other fully aquatic fishes, implying that cutaneous ammonia excretion is not exclusive to amphibious fishes. Overall, our results demonstrate that similar nitrogen excretion strategies while out of water were used by all killifish species tested; possibly the result of shared ancestral amphibious traits, phenotypic convergence, or a combination of both.

Flexible ammonia handling strategies using both cutaneous and branchial epithelia in the highly ammonia-tolerant Pacific hagfish.

Hagfish consume carrion, potentially exposing them to hypoxia, hypercapnia, and high environmental ammonia (HEA). We investigated branchial and cutaneous ammonia handling strategies by which Pacific hagfish (Eptatretus stoutii) tolerate and recover from high ammonia loading. Hagfish were exposed to HEA (20 mmol/l) for 48 h to elevate plasma total ammonia (TAmm) levels before placement into divided chambers for a 4-h recovery period in ammonia-free seawater where ammonia excretion (JAmm) was measured independently in the anterior and posterior compartments. Localized HEA exposures were also conducted by subjecting hagfish to HEA in either the anterior or posterior compartments. During recovery, HEA-exposed animals increased JAmm in both compartments, with the posterior compartment comprising ~20% of the total JAmm compared with ~11% in non-HEA-exposed fish. Plasma TAmm increased substantially when whole hagfish and the posterior regions were exposed to HEA. Alternatively, plasma TAmm did not elevate after anterior localized HEA exposure. JAmm was concentration dependent (0.05-5 mmol/l) across excised skin patches at up to eightfold greater rates than in skin sections that were excised from HEA-exposed hagfish. Skin excised from more posterior regions displayed greater JAmm than those from more anterior regions. Immunohistochemistry with hagfish-specific anti-rhesus glycoprotein type c (α-hRhcg; ammonia transporter) antibody was characterized by staining on the basal aspect of hagfish epidermis while Western blotting demonstrated greater expression of Rhcg in more posterior skin sections. We conclude that cutaneous Rhcg proteins are involved in cutaneous ammonia excretion by Pacific hagfish and that this mechanism could be particularly important during feeding.

Simultaneous and multi-point measurement of ammonia emanating from human skin surface for the estimation of whole body dermal emission rate.

Ammonia is one of the members of odor gases and a possible source of odor in indoor environment. However, little has been known on the actual emission rate of ammonia from the human skin surface. Then, this study aimed to estimate the whole-body dermal emission rate of ammonia by simultaneous and multi-point measurement of emission fluxes of ammonia employing a passive flux sampler - ion chromatography system. Firstly, the emission fluxes of ammonia were non-invasively measured for ten volunteers at 13 sampling positions set in 13 anatomical regions classified by Kurazumi et al. The measured emission fluxes were then converted to partial emission rates using the surface body areas estimated by weights and heights of volunteers and partial rates of 13 body regions. Subsequent summation of the partial emission rates provided the whole body dermal emission rate of ammonia. The results ranged from 2.9 to 12mgh-1 with an average of 5.9±3.2mgh-1 per person for the ten healthy young volunteers. The values were much greater than those from human breath, and thus the dermal emission of ammonia was found more significant odor source than the breath exhalation in indoor environment.

Elementary immunology: Na+ as a regulator of immunity.

The skin can serve as an interstitial Na+ reservoir. Local tissue Na+ accumulation increases with age, inflammation and infection. This increased local Na+ availability favors pro-inflammatory immune cell function and dampens their anti-inflammatory capacity. In this review, we summarize available data on how NaCl affects various immune cells. We particularly focus on how salt promotes pro-inflammatory macrophage and T cell function and simultaneously curtails their regulatory and anti-inflammatory potential. Overall, these findings demonstrate that local Na+ availability is a promising novel regulator of immunity. Hence, the modulation of tissue Na+ levels bears broad therapeutic potential: increasing local Na+ availability may help in treating infections, while lowering tissue Na+ levels may be used to treat, for example, autoimmune and cardiovascular diseases.

A Detailed Protocol for Perspiration Monitoring Using a Novel, Small, Wireless Device.

Perspiration monitoring can be utilized for the detection of certain diseases, such as thermoregulation and mental disorders, particularly when the patients are unaware of such disorders or are having difficulty expressing their symptoms. Until now, several devices for perspiration monitoring have been developed; however, such devices tend to have a relatively large exterior, considerable power consumption, and/or less sensitivity. Recently, we developed a small, wireless device for perspiration monitoring. The device consists of a temperature/relative humidity (T/RH) sensor, battery-driven small data logger, and silica gel as a desiccant in a small cylindrical exterior. The T/RH sensor is placed between the detection windows (through which the water vapor from the skin enters) and the silica gel. The underlying principle of the perspiration monitoring device is based on Fick's law of diffusion, which means that water vapor flux from the skin to the silica gel (i.e. transepidermal water loss and perspiration) can be captured by change in humidity at the T/RH sensor. In addition, a baseline subtraction method was adopted to distinguish perspiration and transepidermal water loss. As shown in the previous report, the developed device can monitor the perspiration at any sites of the body in an easy, wireless manner. However, detailed methods of how to use the device have not been disclosed yet. In this article, therefore, we would like to show the point-by-point tutorials of how to use the device for perspiration monitoring, by showing the sympathetic activity test with the sympathetic skin response monitoring as an example.

Low sodium status in cystic fibrosis-as assessed by calculating fractional Na(+) excretion-is associated with decreased growth parameters.

BACKGROUND: In CF infants, normonatremic Na(+) depletion (NNaD), identified by fractional Na(+) excretion (FENa) values <0.5%, was recently linked to impaired growth. Our paper investigates the relationship between FENa and growth in CF children >2years. METHODS: FENa values were calculated in 35 CF and 24 control children, and tested for correlations with z-scores for weight, height and BMI. RESULTS: All CF children and controls had normal plasma Na(+) concentrations. A total of 25 of 35 (71.4%) CF patients had decreased FENa values <0.5% (group I). FENa results of 10 CF patients (group II) and 23/24 controls (group III) were normal. In Na(+)-depleted CF children, compared to normal controls, mean z-scores for weight (-0.18±0.87 vs +1.03±0.57, p<0.001), height (-0.06±0.89 vs +0.53±0.72, p=0.009) and BMI (-0.22±0.87 vs +1.00±1.06, p<0.001) were significantly reduced. Also, we found positive correlations between FENa values and z-scores for weight (r=0.521), height (r=0.292) and BMI (r=0.468), respectively. CONCLUSION: NNaD may contribute to poor growth in CF.

Percutaneous excretion of iron and ferritin (through Al-hijamah) as a novel treatment for iron overload in beta-thalassemia major, hemochromatosis and sideroblastic anemia.

Iron overload is a big challenge when treating thalassemia (TM), hemochromatosis and sideroblastic anemia. It persists even after cure of TM with bone marrow transplantation. Iron overload results from increased iron absorption and repeated blood transfusions causing increased iron in plasma and interstitial fluids. Iron deposition in tissues e.g. heart, liver, endocrine glands and others leads to tissue damage and organ dysfunction. Iron chelation therapy and phlebotomy for iron overload have treatment difficulties, side effects and contraindications. As mean iron level in skin of TM patients increases by more than 200%, percutaneous iron excretion may be beneficial. Wet cupping therapy (WCT) is a simple, safe and economic treatment. WCT is a familiar treatment modality in some European countries and in Chinese hospitals in treating different diseases. WCT was reported to clear both blood plasma and interstitial spaces from causative pathological substances (CPS). Standard WCT method is Al-hijamah (cupping, puncturing and cupping, CPC) method of WCT that was reported to clear blood and interstitial fluids better than the traditional WCT (puncturing and cupping method, PC method of WCT). In other word, traditional WCT may be described as scarification and suction method (double S technique), while Al-hijamah may be described as suction, scarification and suction method (triple S technique). Al-hijamah is a more comprehensive treatment modality that includes all steps and therapeutic benefits of traditional dry cupping therapy and WCT altogether according to the evidence-based Taibah mechanism (Taibah theory). During the first cupping step of Al-hijamah, a fluid mixture is collected inside skin uplifting due to the effect of negative pressure inside sucking cups. This fluid mixture contains collected interstitial fluids with CPS (iron, ferritin and hemolyzed RBCs in thalassemia), filtered fluids (from blood capillaries) with iron and hemolyzed blood cells (hemolyzed RBCs, WBCs and platelets). That fluid mixture does not contain intact blood cells (having diameters in microns) that are too big to pass through pores of skin capillaries (6-12nm in diameter) and cannot be filtered. Puncturing skin upliftings and applying second cupping step excrete collected fluids. Skin scarifications (shartat mihjam in Arabic) should be small, superficial (0.1mm in depth), short (1-2mm in length), multiple, evenly distributed and confined to skin upliftings. Sucking pressure inside cups (-150 to -420mmHg) applied to skin is transmitted to around skin capillaries to be added to capillary hydrostatic pressure (-33mmHg at arterial end of capillaries and -13mmHg at venous end of capillaries) against capillary osmotic pressure (+20mmHg). This creates a pressure gradient and a traction force across skin and capillaries and increases filtration at arterial end of capillaries at net pressure of -163 to -433mmHg and at venous end of capillaries at net pressure of -143 to -413mmHg resulting in clearance of blood from CPS (iron, ferritin and hemolyzed blood cells). Net filtration pressure at renal glomeruli is 10mmHg i.e. Al-hijamah exerts a more pressure-dependent filtration than renal glomeruli. Al-hijamah may benefit patients through inducing negative iron balance. Interestingly, Al-hijamah was reported to decrease serum ferritin significantly (by about 22%) in healthy subjects while excessive traditional WCT was reported to cause iron deficiency anemia. Al-hijamah is a highly recommended treatment in prophetic medicine. In conclusion, Al-hijamah may be a promising adjuvant treatment for iron overload in TM, hemochromatosis and sideroblastic anemia.

Latent heat loss and sweat gland histology of male goats in an equatorial semi-arid environment.

The objective of this work was to quantify the heat loss by cutaneous evaporation of goats in an equatorial semi-arid environment. The latent heat loss from the body surfaces of these ten undefined breed goats was measured using a ventilated capsule in sun and shade and in the three body regions (neck, flank and hindquarters). Skin samples from these three regions were histologically analyzed to relate the quantity of sweat glands, the area of sweat glands and the epithelium thickness of each of these regions to the heat loss by cutaneous evaporation of the examined goats. The epithelium thickness that was measured varied significantly for body regions with different quantities and areas of sweat glands (P < 0.01). Among the body regions that were examined, the samples from the neck demonstrated the highest epithelium thickness (16.23 ± 0.13 µm). However, the samples of sweat glands from the flank had the biggest area (43330.51 ± 778.71 µm(2)) and quantity per square centimeter (390 ± 9 cm(-2)). After the animals were exposed to sun, the flanks lost the greatest amount of heat by cutaneous evaporation (73.03 ± 1.75 W m(-2)) and possessed the highest surface temperatures (39.47 ± 0.18°C). The histological characteristics may have influenced the heat loss by cutaneous evaporation that was observed in the flank region after the animals were exposed to sun.