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1	The impact of exercise duration and environmental conditions upon the incidence of exercise induced cardiac fatigue (EICF) Shave, Robert E. January 2003 (has links) No description available. 616 Normobaric normoxia
2	The Effect of Normobaric Hypoxia on Power Output During Multiple Wingate Anaerobic Tests Nielsen, Corey Michael 05 May 2017 (has links) No description available. Anatomy and Physiology Kinesiology Physiology lactate peak power oxygen saturation normoxia
3	Vliv různého nasycení vody kyslíkem na příjem krmiva a růst candáta obecného (Sander lucioperca) v intenzivním chovu. / The effect of different oxygen saturation on feed intake and growth of pikeperch (Sander lucioperca) in intensive culture. MATOUŠEK, Jan January 2012 (has links) This diploma thesis is focused on culture of pikeperch under controlled conditions and tested the optimal environmental conditions for their good growth and survival. The aim of this work was to test the effect of different oxygen saturation on survival, growth, feed intake, feed conversion rate and condition of pikeperch Pikeperch (mean body weight 10.3 g; n=810) habituated to artificial feed were placed in culture tank of the same volume of water and environmental conditions. Fish were fed ad-libitum. Three different oxygen saturations were tested in triplicate: normoxia with saturation of 85-95% O2, hypoxia with saturation of 55-65% O2 and hyperoxia with saturation of 145-155% O2. The experiment lasted 82 days and was divided into five periods. Biometric measurements of fish were performed at the end of each period. Cumulative survival, fish growth, amount of received feed, specific growth rate and condition factor were used for evaluation of our results. The results showed the positive effect of hyperoxia on feed intake and growth of fish. Slower growth was observed in hypoxia. The mean weight gain for the whole experiment was followed: normoxia 28.2 g, hyperoxia 37.7 g and hypoxia 22.9 g.
4	Vliv nasycení vody kyslíkem na příjem krmiva a růst síha peledě (Coregonus peled) v intenzivním chovu / Influence of oxygen saturation on feed intake and growth of peled whitefish (Coregonus Peled) in intensive farming SEICHERSTEIN, Adam January 2014 (has links) The results of an experimental rearing of peled under different oxygen regimes are presented in this work. Four variants were tested in three repetitions (hypoxia 55-65 %, normoxia 85-95 %, permanent hyperoxia 145-155 % and alternate hyperoxia 145-155 % during the day and 85-95 % overnight). Also the oxygen consumption of fish with weight from 4.5 to 20 g at temperatures of 15, 19 and 23 °C was measured.
5	Efeitos do treinamento hipóxico intermitente sobre variáveis hematológicas e capacidade de performance / Effects of the intermittent hypoxic training about hematological variables and the capacity of performance Geller, César Alcides 09 August 2005 (has links) The goal of the present study aimed at the assessment of the influences of intermittent hypoxic training (IHT) sessions on haematological parameters, aerobic capacity (AC), and running performance (RP), under hypoxic and normoxic conditions. The group of study was constituted by nine (09) volunteers of Military Pentathlon Athletes, male sex, with mean ages of 23 years old (23 ± 3,6). These athletes underwent (pre-) and post-testing measurements of maximum effort in normoxyc and hypoxic conditions - 13% O2 (simulated altitude 3.800 meters). In the course of the research work hemograms, cardiac frequency, blood lactate concentration [lact], haemoglobin oxygen saturation, the index of perception of effort and ergospirometry variables were fully measured and analysed. The assessments were done in twenty-nine (29) sessions of IHT, with 13% of oxygen concentration (one hour, five times a week). The statistics analyses using the Wilcoxon test showed a significant decrease in the number of erythrocytes and MCHC (p< 0,05). No changes were noticed in the blood lactate concentration [lact], cardiac frequency (FC) and in the maximum VO2 in normoxyc conditions. However, there was an expressive reduction of the [lact] in different running velocities in hypoxic (5, 4, 7, 2, 9, 0, 10, 8, 12,6 km/h / p<0,05). It was also observed a significant increase in the distance running in normoxyc and hypoxic (p<0,05), and a decrease of the running time in hypoxic. In conclusion, the dosage of IHT applied in this study was efficient to increase the performance under normoxyc and hypoxic conditions, in spite of a significant reduction in the numbers of the erythrocytes and a low decrease in the hematocrits numbers. The result in hypoxic showed also that this method can be used at sea level as an alternative of preparation for high-altitude competitions. / Este estudo teve por objetivo avaliar a influência de sessões de treinamento hipóxico intermitente (THI) sobre parâmetros hematológicos, capacidade aeróbica e o desempenho de corrida em condições de hipoxia e normoxia. Fizeram parte do grupo de estudo 9 atletas voluntários, sexo masculino (idade média 23 anos - DP 3,6), praticantes de pentatlo militar. Os indivíduos foram submetidos a pré e pós-testes de esforço máximo em normoxia e hipoxia 13% O2 (3.800 m de altitude). Analisou-se hemograma, freqüência cardíaca, concentração sangüínea de lactato [lact], saturação de oxigênio na hemoglobina, Índice de Percepção de Esforço e variáveis ergoespirométricas. O tratamento foi composto por 29 sessões de THI, concentração de 13% de oxigênio (1 hora, 5 vezes por semana). As análises estatísticas, feitas através do teste de Wilcoxon, apresentaram diminuição significativa no número de eritrócitos e CHCM (p < 0,05). Não foi constatada alteração da [lact], FC e VO2 máx. em normoxia. Porém, houve diminuição significativa da [lact] em diferentes velocidades de corrida em hipoxia (5,4, 7,2, 9,0, 10,8, 12,6 km/h / p<0,05). Observou-se também aumento significativo na distância de corrida em normoxia e hipoxia (p<0,05) e diminuição do tempo de corrida em hipoxia. Conclui-se que o THI, na dosagem empregada neste estudo, foi eficiente para proporcionar aumento de performance em ambas as situações, apesar da significativa redução no número de eritrócitos e da pequena queda do hematócrito. O resultado em hipoxia demonstra ainda, que o método pode ser usado, ao nível do mar, como alternativa de preparação para competições em altitude. Hipoxia Normoxia THI VO2 máximo Performance de corrida Hypoxia Maximum VO2 Race performance CNPQ::CIENCIAS DA SAUDE::EDUCACAO FISICA
6	STUDIUM ZÁKLADNÍCH MECHANISMŮ PERITONEÁLNÍHO ZÁNĚTU U CANDÁTA OBECNÉHO (Sander lucioperca) CHÁBERA, Jan January 2019 (has links) Pike-perch (Sander lucioperca) is a species of fish whose breeding in recirculation systems has a great prospect in the years to come. Due to the unfavorable conditions of intensive rearing of these fish in recirculation systems, they are often exposed to stress resulting in reduced fish defenses. Thus, fish are exposed to attack of a wide range of bacteria. Although there are preventive measures to protect fish against pathogen attack, knowledge of the immune system and the immune response of the fish is crucial for further evolution of vaccination. Even though we know the mechanisms of immune response of many fish species,but the knowledge of the pike-perch's immune response is very limited.
7	Causes and Consequences of A Glutamine Induced Normoxic HIF1 Activity for the Tumor Metabolism Kappler, Matthias, Pabst, Ulrike, Weinholdt, Claus, Taubert, Helge, Rot, Swetlana, Kaune, Tom, Kotrba, Johanna, Porsch, Martin, Güttler, Antje, Bache, Matthias, Krohn, Knut, Bull, Fabian, Riemann, Anne, Wickenhauser, Claudia, Seliger, Barbara, Schubert, Johannes, Al-Nawas, Bilal, Thews, Oliver, Grosse, Ivo, Vordermark, Dirk, Eckert, Alexander W. 25 January 2024 (has links) The transcription factor hypoxia-inducible factor 1 (HIF1) is the crucial regulator of genes that are involved in metabolism under hypoxic conditions, but information regarding the transcriptional activity of HIF1 in normoxic metabolism is limited. Different tumor cells were treated under normoxic and hypoxic conditions with various drugs that affect cellular metabolism. HIF1ff was silenced by siRNA in normoxic/hypoxic tumor cells, before RNA sequencing and bioinformatics analyses were performed while using the breast cancer cell line MDA-MB-231 as a model. Differentially expressed genes were further analyzed and validated by qPCR, while the activity of the metabolites was determined by enzyme assays. Under normoxic conditions, HIF1 activity was significantly increased by (i) glutamine metabolism, which was associated with the release of ammonium, and it was decreased by (ii) acetylation via acetyl CoA synthetase (ACSS2) or ATP citrate lyase (ACLY), respectively, and (iii) the presence of L-ascorbic acid, citrate, or acetyl-CoA. Interestingly, acetylsalicylic acid, ibuprofen, L-ascorbic acid, and citrate each significantly destabilized HIF1ff only under normoxia. The results from the deep sequence analyses indicated that, in HIF1-siRNA silenced MDA-MB-231 cells, 231 genes under normoxia and 1384 genes under hypoxia were transcriptionally significant deregulated in a HIF1-dependent manner. Focusing on glycolysis genes, it was confirmed that HIF1 significantly regulated six normoxic and 16 hypoxic glycolysis-associated gene transcripts. However, the results from the targeted metabolome analyses revealed that HIF1 activity affected neither the consumption of glucose nor the release of ammonium or lactate; however, it significantly inhibited the release of the amino acid alanine. This study comprehensively investigated, for the first time, how normoxic HIF1 is stabilized, and it analyzed the possible function of normoxic HIF1 in the transcriptome and metabolic processes of tumor cells in a breast cancer cell model. Furthermore, these data imply that HIF1 compensates for the metabolic outcomes of glutaminolysis and, subsequently, theWarburg effect might be a direct consequence of the altered amino acid metabolism in tumor cells. info:eu-repo/classification/ddc/610 ddc:610
8	PHYSIOLOGICAL DIFFERENCES BETWEEN FIT AND UNFIT COLLEGE-AGE MALES DURING EXERCISE IN NORMOBARIC HYPOXIA Bliss, Matthew Vern 16 December 2013 (has links) No description available. Health Environmental Health Physiology Hypoxia Normoxia Altitude Exercise Cerebral Blood Flow Cerebral Oxygenation Near Infrared Spectroscopy Arterial Saturation Cycling Exercise Fitness Level Brain Blood Flow Lactate Physiology
9	The Hypoxic Regulation and Function of Hypoxiainducible Factor 2α (HIF-2α) In an Adrenomedullary Chromaffin Cell Line Brown, Stephen T. 04 1900 (has links) <p> Exposure to chronic low oxygen (hypoxia) leads to a series of adaptive responses involving changes in gene expression that are critical for cell, tissue, and organismal survival. These changes are mediated by an important set of regulators belonging to the hypoxia inducible factor (HIF) family of transcription factors (e.g. HIF-lα, HIF-2α, HIF3α) which undergo rapid degradation during normal oxygen (normoxia) but are rapidly stabilized during hypoxia. While the role of HIF-1α has been extensively studied in many cell types, there have been relatively few studies on the role of HIF-2α, though recent evidence suggests its function maybe tissue specific. This thesis examined the hypothesis that HIF-2α plays a central role in the development and function of catecholaminergic cells of the sympathoadrenal (SA) lineage. The study was aided by use of an immortalized line of rat adrenomedullary chromaffin cells (i.e. MAH cells), derived from fetal SA progenitors, which express several hypoxia-sensitive properties characteristic of native cells in the adrenal gland. In Chapter 2, I investigated the potential contributions of mitochondrial reactive oxygen species (ROS) and 0 2 consumption to HIF-2α induction in MAH cells exposed to chronic hypoxia (2% O(2); 24 hr). In MAH cells, chronic hypoxia caused an increase in HIF-2α induction which was blocked by inhibition of any of the mitochondrial complexes using pharmacological agents, or by specific inhibition of complexes III and IV using RNAi techniques. It was found that in this 0 2-sensitive chromaffin cell line mitochondrial O(2) consumption, rather than changes in ROS, regulated HIF-2α induction during hypoxia. In Chapter 3, I investigated the hypothesized role of HIF-2α in the development of the catecholaminergic phenotype in cells of the SA lineage using the MAH cell line as a model. Mutant MAH cells, with depleted HIF-2α due to siRNA knock-down, showed dramatically lower levels of dopamine and noradrenaline compared to untransfected and scrambled control cells, regardless of whether the cells were cultured under normoxia or chronic hypoxia. This was correlated with a marked reduction in the expression of DOPA decarboxylase (DDC) and dopamine B hydroxylase (DBH), though the expression of tyrosine hydroxylase (TH) was unaffected. Moreover, HIF-2α was able to bind to a region of the DDC gene promoter which contains two putative hypoxia response elements (HREs). These data suggest that a basal level of HIF-2α function is required for the normal developmental expression of DDC and DBH in SA progenitor cells, and that loss of this function leads to impaired catecholamine (CA) biosynthesis. In Chapter 4, I investigated genes regulated by chronic hypoxia in MAH cells, with a focus on those involved in CA metabolism, storage, and secretion. Using microarray analysis combined with QPCR and RNAi knock-down methodology I uncovered several genes, involved in amine vesicular packaging, trafficking and secretion, which were upregulated during chronic hypoxia. One gene specifically, the adenosine A(2A) receptor (A(2A)R) gene, which appears to modulate CA secretion via autocrine or paracrine actions of extracellular adenosine, was dramatically upregulated in chronic hypoxia. Interestingly, this effect was completely abolished in HIF-2α knockdown MAH cells, suggesting a critical involvement of HIF-2α. Chromatin immunoprecipitation (ChIP) assays revealed that HIF-2α bound to the promoter region of the A(2A)R gene which contains a putative hypoxia response element (HRE) immediately upstream of exon 1. Ratiometric fluorescence measurements of intracellular Ca(2+) revealed that adenosine (50 μM) potentiated the high K(+)-evoked rise in [Ca(2+)]i in MAH cells. This effect of adenosine was further enhanced after chronic hypoxia, but was abolished in HIF-2α knock-down cells. In conclusion, these data suggest that HIF-2α is a key regulator of several genes involved in CA biosynthesis, and of others that mediate the facilitatory effects of chronic hypoxia on CA secretion in sympathoadrenal derivatives. / Thesis / Doctor of Philosophy (PhD) Biology Chronic low Oxygen hypoxia cell tissue organismal survival HIF Hypoxia Inducible Factor transcription factors rapid degradation normal oxygen normoxia SA sympathoadrenal rat adrenomedullary chromaffin cells MAH cells ROS Reactive Oxygen Species mitochondrial pharmacological agents RNAi catecholaminergic phenotype MAH siRNA DOPA DDC decarboxylase dopamine β hydroxylase Adenosine paracrine extracellular adenosine
10	Six weeks of high intensity interval training with hyperoxia or normoxia in trained cyclists : A polarized and periodized training approach / Sex veckors högintensiv intervallträning med hyperoxi eller normoxi för tränade cyklister : En polariserad och periodiserad träningsmodell Manselin, Tom, Södergård, Olof January 2015 (has links) Aim The main aim of this study was to investigate the longitudinal effects on cycling performance using a polarized and periodized scheme that was highly supervised and controlled. The second aim was to investigate the effect of using Hyperoxia. The questions used to address the aim were: (1) How does overall performance change after a six-week training intervention? (2) What is the time-course and pattern of performance changes to the training scheme? (3) How does the performance change within the groups? Method Nineteen male and female cyclists started the study (13 male and 6 female), however only 12 completed it (8 male and 4 female). The characteristics for the 12 subjects were: age (year) 33.6 ± 6.8, height (cm) 177 ± 9.1, body mass (kg) 73.4 ± 8.8. Using a randomized, double blind design, the test subjects were divided in to hyperoxia (HOT) (n = 6) and normoxia (NOT) (n = 6) training groups. Over a six week period the subjects followed a controlled polarized periodization that included 15 high intensity interval training (HIIT) sessions (3 x 8 min, 3 x 8 + 4 min, 4 x 8 min & 4 x 4 min) on maximal sustainable intensity (isoeffort) on a cycle ergometer. The dosage of oxygen was administered intermittently by the oxelerate device. A 20 min all out test was performed as pre- and post test. Results The whole group (n = 12) increased mean power output (W) by 6.4 % (P = 0.002). The relative power output (W/kg) increased significantly 8.2 % (P = 0.0011). The HOT group (n = 6) increased their power output by 8.3 % (P = 0.028) and their relative power output increased by 9.4 % (P=0.011). The whole group (P = 12) significantly increased their VO2mean by 4.1 % (P = 0.03) and in the relative value by 5.4 % (P = 0.01) on the 20 min all out test. The whole group also had a significant increase in VO2peak of 3.7 % (P = 0.04). A very strong correlation could be found between the training data and the performance test. Conclusions The training intervention was favourable for increasing performance and VO2peak in cycling. Usage of hyperoxia during the training intervention increases the performance. / Syfte och frågeställningar Huvudsyftet med denna studie var att undersöka de longitudinella effekter på prestation i cykling med hjälp av ett polariserat och periodiserat träningsupplägg som var väl övervakat och kontrollerat. Det andra syftet var att undersöka effekten av att använda hyperoxi. De frågeställningar som hjälpte att besvara syftet var: (1) Hur förändras prestationen efter en sex veckors träningsintervention? (2) Hur anpassar sig försökspersonerna till träningsschemat över tid? (3) Hur förändras prestationen inom grupperna? Metod 19 manliga och kvinnliga cyklister deltog i studien (13 manliga och 6 kvinnliga), 12 fullföljde hela studien (8 manliga och 4 kvinnliga). Karaktäristiken för de 12 försökspersonerna var: ålder (år) 33.6 ± 6.8, längd (cm) 177 ± 9.1, vikt (kg) 73.4 ± 8.8. Försökspersonerna delades in i hyperoxi (HOT) (n = 6) och normoxi (NOT) (n = 6), studien var dubbelblind. Under sex veckor följde försökspersonerna en kontrollerad polariserad periodisering som inkluderade 15 högintensiva intervallträningspass (HIIT) (3 x 8 min, 3 x 8 + 4 min, 4 x 8 min & 4 x 4 min) på högsta genomförbara intensitet (isoeffort) på cykelergometer. Doseringen av syre administrerades intermittent genom Oxelerate-enheten. Ett 20 min all-out test utfördes som för- och eftertest. Resultat Hela gruppen (n = 12) ökade signifikant på prestationstestet (W) med 6.4 % (P = 0.002). Den relativa effekten (W/kg) ökade signifikant med 8.2% (P = 0.0011). HOT (n = 6) ökade signifikant på prestationstestet med 8.3% (P = 0.028) och den relativa effekten ökade med 9.4% (P = 0.011). Hela gruppen (n = 12) ökade signifikant i VO2medel under prestationstestet med 4.1 % (P = 0.03) och i det relativa värdet med 5.4 % (P = 0.01). Hela gruppen hade också en signifikant ökning av VO2peak med 3.7 % (P = 0.04). En mycket stark korrelation hittades mellan träningspassdata och prestationstestet. Slutsats Träningsupplägget är gynnsamt för ökning av prestation och VO2peak i cykling. Användning av hyperoxi under träningsupplägget ökar prestationen. hyperoxia running cycling VO2max interval training HIIT HIT polarized periodized normoxia oxelerate O2 oxygen lactate glucose performance monark SRM power output watt isoeffort VO2peak lactate treshold saturation SaO2 TRIMP training load RPE Bannister oxygen uptake ventilation oxygen supplementation GIH Karolinska Institutet hypoxia high intensity interval training periodization hyperoxi löpning cykling intervallträning högintensiv intervallträning polariserat periodiserat normoxi laktat glukos prestation prestationstest laktattröskel träningsbelastning syreupptag syretillförsel hypoxi höghöjdsträning Sport and Fitness Sciences Idrottsvetenskap Physiology Fysiologi

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