TY - JOUR A1 - Ruf, Katharina A1 - Demerath, Antonia A1 - Hebestreit, Helge A1 - Kunzmann, Steffen T1 - Is sweat testing for cystic fibrosis feasible in patients with down syndrome? JF - BMC Pulmonary Medicine N2 - Background: Recurrent airway infections are common in patients with Down's syndrome (DS). Hence, ruling out Cystic Fibrosis (CF) in these patients is often required. In the past, the value of sweat testing the gold standard to diagnose CF -has been questioned in DS as false positive results have been reported. However, these reports are based on measurements of sweat osmolality or sodium concentrations, not chloride concentrations. This study analyses sweat secretion rate and chloride concentration in sweat samples of patients with DS in comparison to healthy controls. Methods: We assessed sweat samples in 16 patients with DS and 16 healthy controls regarding sweat secretion rate (SSR) and sweat chloride concentration. Results: All measured chloride concentrations were within the normal range. The chloride concentrations were slightly, but not significantly lower in patients with DS (15,54 mmol/l (±4,47)) compared to healthy controls (18,31 mmol/l (±10,12)). While no gender gap in chloride concentration could be found, chloride concentration increased with age in both groups. Insufficient sweat was collected in 2 females with DS (12.5% of the study group) but not in an individual of the control group. A significant lower sweat secretion rate was found in the DS group (27,6 μl/30 min (± 12,18)) compared to the control group (42,7 μl/30 min (± 21,22)). In a sub-analysis, female patients produced significantly less sweat (20,8 ± 10,6 μl/30 min) than male patients with DS (36,4 ± 7,8 μl/30 min), which accounts for the difference between patients and controls. Furthermore, while the sweating secretion rate increased with age in the control group, it did not do so in the DS group. Once again this was due to female patients with DS, who did not show a significant increase of sweat secretion rate with age. Conclusions: Sweat chloride concentrations were within the normal range in patients with DS and therefore seem to be a reliable tool for testing for CF in these patients. Interestingly, we found a reduced sweat secretion rate in the DS group. Whether the last one has a functional and clinical counterpart, possibly due to a disturbed thermoregulation in DS patients, requires further investigation. KW - sweat secretion rate KW - sweat osmolality KW - gender gap KW - non-responder KW - thermoregulation Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175519 VL - 18 IS - 8 ER - TY - JOUR A1 - Zinner, C. A1 - Krueger, M. A1 - Reed, J. L. A1 - Kohl-Bareis, M. A1 - Holmberg, H. C. A1 - Sperlich, B. T1 - Exposure to a combination of heat and hyperoxia during cycling at submaximal intensity does not alter thermoregulatory responses JF - Biology of Sport N2 - In this study, we tested the hypothesis that breathing hyperoxic air (F\(_{in}\)O\(_2\) = 0.40) while exercising in a hot environment exerts negative effects on the total tissue level of haemoglobin concentration (tHb); core (T\(_{core}\)) and skin (T\(_{skin}\)) temperatures; muscle activity; heart rate; blood concentration of lactate; pH; partial pressure of oxygen (P\(_a\)O\(_2\)) and carbon dioxide; arterial oxygen saturation (S\(_a\)O\(_2\)); and perceptual responses. Ten well-trained male athletes cycled at submaximal intensity at 21°C or 33°C in randomized order: first for 20 min while breathing normal air (FinO\(_2\) = 0.21) and then 10 min with F\(_{in}\)O\(_2\) = 0.40 (HOX). At both temperatures, S\(_a\)O\(_2\) and P\(_a\)O\(_2\), but not tHb, were increased by HOX. Tskin and perception of exertion and thermal discomfort were higher at 33°C than 21°C (p < 0.01), but independent of F\(_{in}\)O\(_2\). T\(_{core}\) and muscle activity were the same under all conditions (p > 0.07). Blood lactate and heart rate were higher at 33°C than 21°C. In conclusion, during 30 min of submaximal cycling at 21°C or 33°C, T\(_{core}\), T\(_{skin}\) and T\(_{body}\), tHb, muscle activity and ratings of perceived exertion and thermal discomfort were the same under normoxic and hyperoxic conditions. Accordingly, breathing hyperoxic air (F\(_{in}\)O\(_2\) = 0.40) did not affect thermoregulation under these conditions. KW - heat stress KW - hyperthermia KW - skin blood flow KW - thermoregulation KW - vasoconstriction Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160993 VL - 33 IS - 1 ER - TY - JOUR A1 - Klein, Barett Anthony A1 - Stiegler, Martin A1 - Klein, Arno A1 - Tautz, Jürgen T1 - Mapping Sleeping Bees within Their Nest: Spatial and Temporal Analysis of Worker Honey Bee Sleep JF - PLOS ONE N2 - Patterns of behavior within societies have long been visualized and interpreted using maps. Mapping the occurrence of sleep across individuals within a society could offer clues as to functional aspects of sleep. In spite of this, a detailed spatial analysis of sleep has never been conducted on an invertebrate society. We introduce the concept of mapping sleep across an insect society, and provide an empirical example, mapping sleep patterns within colonies of European honey bees (Apis mellifera L.). Honey bees face variables such as temperature and position of resources within their colony's nest that may impact their sleep. We mapped sleep behavior and temperature of worker bees and produced maps of their nest's comb contents as the colony grew and contents changed. By following marked bees, we discovered that individuals slept in many locations, but bees of different worker castes slept in different areas of the nest relative to position of the brood and surrounding temperature. Older worker bees generally slept outside cells, closer to the perimeter of the nest, in colder regions, and away from uncapped brood. Younger worker bees generally slept inside cells and closer to the center of the nest, and spent more time asleep than awake when surrounded by uncapped brood. The average surface temperature of sleeping foragers was lower than the surface temperature of their surroundings, offering a possible indicator of sleep for this caste. We propose mechanisms that could generate caste-dependent sleep patterns and discuss functional significance of these patterns. KW - apis mellifera KW - age polyethism KW - waggle dance KW - colony KW - hive KW - thermoregulation KW - deprivation KW - dynamics KW - rhythms KW - comb Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115857 SN - 1932-6203 VL - 9 IS - 7 ER -