TY - THES A1 - Stehle, Jens T1 - Der kolloidosmotische Druck von Blutplasma und Plasmaersatzmitteln unter Aspekten der Innenohrtherapie T1 - The colloid osmotic pressure of blood plasma and plasma volume expanders under aspects of inner ear therapy N2 - Diese Arbeit untersucht die meßtechnischen Voraussetzungen, Einfluß- und Störfaktoren bei Messungen des kolloidosmotischen Druckes (KOD) und den circadianen Rhythmus des plasmatischen KOD. In Anlehnung an die Dissertation von R. Hampe [2000] werden die Ergebnisse der Messungen des KOD von über 200 Patienten mit Innenohrerkrankungen dargestellt. Dabei konnte gezeigt werden, daß ein erhöhter plasmatischer KOD für die Innenohrfunktion als Risikofaktor anzusehen ist. Zusätzlich wurden Molekulargewichtsverteilungen von Humanalbuminlösungen, Humanserumpräparaten, Probandenplasmen und nahezu 30 Plasmaersatzmitteln durch Messungen des KOD mit Membranen unterschiedlicher Porenweite (von 0,5kD bis 1000kD) abgeschätzt und in einem „KOD-Profil“ dargestellt. Damit wurde eine neuartige Möglichkeit zur Charakterisierung kolloidaler Plasmaersatzmittel geschaffen, durch die das am besten geeignete Präparat bei verschiedenen Indikationen bestimmt werden kann. Um bei akzeptablen Meßzeiten verläßliche KOD-Endwerte zu finden, wurde ein Extrapolationsprogramm entwickelt, das bei langsamen Kinetiken zur Errechnung eines Endwertes eingesetzt wurde. N2 - This work examines the metrological prerequisites, influence and interference factors at measurings of the colloidosmotic pressure (COP) and the circadian rhythm for the COP of blood plasma. In dependence on the thesis of R. Hampe [2000] the results of the measurings of the COP are represented by over 200 patients with inner ear diseases. It was possible to show, that an increased COP of blood plasma can be considered a risk factor for the inner ear function. In addition molecular weight distributions of human albumin solutions, human serum solutions, plasma of probands and almost 30 plasma expanders were determined by measurings of COP with several membranes of different porosity (from 0.5 kD to 1000 kD) and represented in a "COP-profile". This is a new representation for the characterization of colloidal plasma solutions by which it is possible to determine the suitable preparation at different indications best. To find reliable COP final values at acceptable measurement times, an extrapolation program was developed for the determination of a final value at slow kinetics. KW - kolloidosmotischer Druck KW - Innenohrerkrankungen KW - Plasmaersatzmittel KW - Circadianer Rhythmus KW - Endolymphe KW - Perilymphe KW - colloidosmotic pressure KW - inner ear disease KW - plasma volume expanders KW - circadian rhythm KW - endolymph KW - perilymph Y1 - 2001 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-1181494 ER - TY - JOUR A1 - Chtourou, Hamdi A1 - Engel, Florian Azad A1 - Fakhfakh, Hassen A1 - Fakhfakh, Hazem A1 - Hammouda, Omar A1 - Ammar, Achraf A1 - Trabelsi, Khaled A1 - Souissi, Nizar A1 - Sperlich, Billy T1 - Diurnal Variation of Short-Term Repetitive Maximal Performance and Psychological Variables in Elite Judo Athletes JF - Frontiers in Physiology N2 - Objectives: The aim of this study was to examine the effect of time of day on short-term repetitive maximal performance and psychological variables in elite judo athletes. Methods: Fourteen Tunisian elite male judokas (age: 21 ± 1 years, height:172 ± 7 cm, body-mass: 70.0 ± 8.1 kg) performed a repeated shuttle sprint and jump ability (RSSJA) test (6 m × 2 m × 12.5 m every 25-s incorporating one countermovement jump (CMJ) between sprints) in the morning (7:00 a.m.) and afternoon (5:00 p.m.). Psychological variables (Profile of mood states (POMS-f) and Hooper questionnaires) were assessed before and ratings of perceived exertion (RPE) immediately after the RSSJA. Results: Sprint times (p > 0.05) of the six repetition, fatigue index of sprints (p > 0.05) as well as mean (p > 0.05) jump height and fatigue index (p > 0.05) of CMJ did not differ between morning and afternoon. No differences were observed between the two times-of-day for anxiety, anger, confusion, depression, fatigue, interpersonal relationship, sleep, and muscle soreness (p > 0.05). Jump height in CMJ 3 and 4 (p < 0.05) and RPE (p < 0.05) and vigor (p < 0.01) scores were higher in the afternoon compared to the morning. Stress was higher in the morning compared to the afternoon (p < 0.01). Conclusion: In contrast to previous research, repeated sprint running performance and mood states of the tested elite athletes showed no-strong dependency of time-of-day of testing. A possible explanation can be the habituation of the judo athletes to work out early in the morning. KW - circadian rhythm KW - repeated sprint running KW - repeated exercise KW - mood KW - fatigue Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189269 SN - 1664-042X VL - 9 ER - TY - JOUR A1 - Grubisic, Maja A1 - Haim, Abraham A1 - Bhusal, Pramod A1 - Dominoni, Davide M. A1 - Gabriel, Katharina M. A. A1 - Jechow, Andreas A1 - Kupprat, Franziska A1 - Lerner, Amit A1 - Marchant, Paul A1 - Riley, William A1 - Stebelova, Katarina A1 - van Grunsven, Roy H. A. A1 - Zeman, Michal A1 - Zubidat, Abed E. A1 - Hölker, Franz T1 - Light Pollution, Circadian Photoreception, and Melatonin in Vertebrates JF - Sustainability N2 - Artificial light at night (ALAN) is increasing exponentially worldwide, accelerated by the transition to new efficient lighting technologies. However, ALAN and resulting light pollution can cause unintended physiological consequences. In vertebrates, production of melatonin—the “hormone of darkness” and a key player in circadian regulation—can be suppressed by ALAN. In this paper, we provide an overview of research on melatonin and ALAN in vertebrates. We discuss how ALAN disrupts natural photic environments, its effect on melatonin and circadian rhythms, and different photoreceptor systems across vertebrate taxa. We then present the results of a systematic review in which we identified studies on melatonin under typical light-polluted conditions in fishes, amphibians, reptiles, birds, and mammals, including humans. Melatonin is suppressed by extremely low light intensities in many vertebrates, ranging from 0.01–0.03 lx for fishes and rodents to 6 lx for sensitive humans. Even lower, wavelength-dependent intensities are implied by some studies and require rigorous testing in ecological contexts. In many studies, melatonin suppression occurs at the minimum light levels tested, and, in better-studied groups, melatonin suppression is reported to occur at lower light levels. We identify major research gaps and conclude that, for most groups, crucial information is lacking. No studies were identified for amphibians and reptiles and long-term impacts of low-level ALAN exposure are unknown. Given the high sensitivity of vertebrate melatonin production to ALAN and the paucity of available information, it is crucial to research impacts of ALAN further in order to inform effective mitigation strategies for human health and the wellbeing and fitness of vertebrates in natural ecosystems. KW - ALAN KW - artificial light at night KW - biological rhythm KW - circadian rhythm KW - melatonin Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-193095 SN - 2071-1050 VL - 11 IS - 22 ER - TY - JOUR A1 - Fujiwara, Yuri A1 - Hermann-Luibl, Christiane A1 - Katsura, Maki A1 - Sekiguchi, Manabu A1 - Ida, Takanori A1 - Helfrich-Förster, Charlotte A1 - Yoshii, Taishi T1 - The CCHamide1 Neuropeptide Expressed in the Anterior Dorsal Neuron 1 Conveys a Circadian Signal to the Ventral Lateral Neurons in Drosophila melanogaster JF - Frontiers in Physiology N2 - The fruit fly Drosophila melanogaster possesses approximately 150 brain clock neurons that control circadian behavioral rhythms. Even though individual clock neurons have self-sustaining oscillators, they interact and synchronize with each other through a network. However, little is known regarding the factors responsible for these network interactions. In this study, we investigated the role of CCHamide1 (CCHa1), a neuropeptide expressed in the anterior dorsal neuron 1 (DN1a), in intercellular communication of the clock neurons. We observed that CCHa1 connects the DN1a clock neurons to the ventral lateral clock neurons (LNv) via the CCHa1 receptor, which is a homolog of the gastrin-releasing peptide receptor playing a role in circadian intercellular communications in mammals. CCHa1 knockout or knockdown flies have a generally low activity level with a special reduction of morning activity. In addition, they exhibit advanced morning activity under light-dark cycles and delayed activity under constant dark conditions, which correlates with an advance/delay of PAR domain Protein 1 (PDP1) oscillations in the small-LNv (s-LNv) neurons that control morning activity. The terminals of the s-LNv neurons show rather high levels of Pigment-dispersing factor (PDF) in the evening, when PDF is low in control flies, suggesting that the knockdown of CCHa1 leads to increased PDF release; PDF signals the other clock neurons and evidently increases the amplitude of their PDP1 cycling. A previous study showed that high-amplitude PDP1 cycling increases the siesta of the flies, and indeed, CCHa1 knockout or knockdown flies exhibit a longer siesta than control flies. The DN1a neurons are known to be receptive to PDF signaling from the s-LNv neurons; thus, our results suggest that the DN1a and s-LNv clock neurons are reciprocally coupled via the neuropeptides CCHa1 and PDF, and this interaction fine-tunes the timing of activity and sleep. KW - circadian clock KW - circadian rhythm KW - CCHamide1 KW - pacemaker neuron KW - neuropeptide KW - pigment-dispersing factor Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-195940 SN - 1664-042X VL - 09 ER - TY - JOUR A1 - Amatobi, Kelechi M. A1 - Ozbek-Unal, Ayten Gizem A1 - Schäbler, Stefan A1 - Deppisch, Peter A1 - Helfrich-Förster, Charlotte A1 - Mueller, Martin J. A1 - Wegener, Christian A1 - Fekete, Agnes T1 - The circadian clock is required for rhythmic lipid transport in Drosophila in interaction with diet and photic condition JF - Journal of Lipid Research N2 - Modern lifestyle is often at odds with endogenously driven rhythmicity, which can lead to circadian disruption and metabolic syndrome. One signature for circadian disruption is a reduced or altered metabolite cycling in the circulating tissue reflecting the current metabolic status. Drosophila is a well-established model in chronobiology, but day-time dependent variations of transport metabolites in the fly circulation are poorly characterized. Here, we sampled fly hemolymph throughout the day and analyzed diacylglycerols (DGs), phosphoethanolamines (PEs) and phosphocholines (PCs) using LC-MS. In wild-type flies kept on sugar-only medium under a light-dark cycle, all transport lipid species showed a synchronized bimodal oscillation pattern with maxima at the beginning and end of the light phase which were impaired in period01 clock mutants. In wild-type flies under constant dark conditions, the oscillation became monophasic with a maximum in the middle of the subjective day. In strong support of clock-driven oscillations, levels of the targeted lipids peaked once in the middle of the light phase under time-restricted feeding independent of the time of food intake. When wild-type flies were reared on full standard medium, the rhythmic alterations of hemolymph lipid levels were greatly attenuated. Our data suggest that the circadian clock aligns daily oscillations of DGs, PEs, and PCs in the hemolymph to the anabolic siesta phase, with a strong influence of light on phase and modality. KW - hemolymph lipids KW - lipidomics KW - circadian rhythm KW - feeding KW - locomotor activity KW - light-driven metabolism Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-349961 VL - 64 IS - 10 ER - TY - JOUR A1 - Born, Dennis-Peter A1 - Zinner, Christoph A1 - Sperlich, Billy T1 - The mucosal immune function is not compromised during a period of high-intensity interval training. Is it time to reconsider an old assumption? JF - Frontiers in Physiology N2 - Purpose: The aim of the study was to evaluate the mucosal immune function and circadian variation of salivary cortisol, Immunoglobin-A (sIgA) secretion rate and mood during a period of high-intensity interval training (HIIT) compared to long-slow distance training (LSD). Methods: Recreational male runners (n = 28) completed nine sessions of either HIIT or LSD within 3 weeks. The HIIT involved 4 × 4 min of running at 90–95% of maximum heart rate interspersed with 3 min of active recovery while the LSD comprised of continuous running at 70–75% of maximum heart rate for 60–80 min. The psycho-immunological stress-response was investigated with a full daily profile of salivary cortisol and immunoglobin-A (sIgA) secretion rate along with the mood state on a baseline day, the first and last day of training and at follow-up 4 days after the last day of training. Before and after the training period, each athlete's running performance and peak oxygen uptake (V·O\(_{2peak}\)) was determined with an incremental exercise test. Results: The HIIT resulted in a longer time-to-exhaustion (P = 0.02) and increased V·O\(_{2peak}\) compared to LSD (P = 0.01). The circadian variation of sIgA secretion rate showed highest values in the morning immediately after waking up followed by a decrease throughout the day in both groups (P < 0.05). With HIIT, the wake-up response of sIgA secretion rate was higher on the last day of training (P < 0.01) as well as the area under the curve (AUC\(_{G}\)) higher on the first and last day of training and follow-up compared to the LSD (P = 0.01). Also the AUC\(_{G}\) for the sIgA secretion rate correlated with the increase in V·O\(_{2peak}\) and running performance. The AUC\(_{G}\) for cortisol remained unaffected on the first and last day of training but increased on the follow-up day with both, HIIT and LSD (P < 0.01). Conclusion: The increased sIgA secretion rate with the HIIT indicates no compromised mucosal immune function compared to LSD and shows the functional adaptation of the mucosal immune system in response to the increased stress and training load of nine sessions of HIIT. KW - high-volume training KW - periodization KW - circadian rhythm KW - cortisol KW - diurnal profile KW - endurance KW - immunoglobin-A Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158025 VL - 8 IS - 485 ER -