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Anaerobic threshold speed (VTAM) was determined for 20 male university students using a continuous treadmill protocol. The onset of anaerobiosis was determined by analyzing excess CO₂ elimination. The following week, all subjects ran at the VTAM median speed of 7.25 miles per hour for 10 minutes. Recovery oxygen consumption was monitored after this run. Application of double exponential equations by computer and subsequent integration, calculated Total, Alactic, and Lactic Oxygen Debts. Subjects who ran above their VTAM (group L-VTAM) had significantly (p < .05) higher total, lactic and alactic debts than those subjects who ran below their VTAM (group H-VTAM). The total debt showed a significant (p < .05) negative correlation (r=-.77) to in; group L-VTAM. This appears to be due to the increasing lactic debt, that was also significantly (p < .05) negatively correlated (r=-.73) to VTAM. Group H-VTAM did not exhibit this characteristic. This study demonstrates that VTAM is a critical factor in determining oxygen debt and therefore, work above this point results in the onset of metabolic acidosis, which may limit the optimal running speed for a given distance. / Education, Faculty of / Kinesiology, School of / Graduate

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Haemophilus parasuis was grown in cystine-supplemented tryptone-yeast extract medium (TYE) sparged with CO$ sb2$-containing gas mixtures. The organism was found to metabolize glucose via acetate- and succinate-producing pathways and a complete tricarboxylic acid cycle was absent. As compared with the oxygen-sufficient organism, oxygen-restricted H. parasuis synthesized higher amounts of high and low potential cytochromes c, exhibited higher activities of the enzymes of the succinate-producing pathway and excreted less acetate and more formate and succinate. The low potential cytochromes c were reduced by NADH and oxidized by fumarate and were situated on both sides of the HOQNO inhibition site of the low potential portion of the electron transport chain, but did not seem strictly required for the NADH:fumarate oxidoreductase activity. It is suggested that the low potential cytochromes c might act as an electron buffer permitting the regeneration of NAD under conditions of scarcity of the final electron acceptor.

Oxygen consumption remains elevated above resting values for a variable period of time after exercise. Exercise intensity and duration, food intake, laboratory conditions, metabolic measurements, gender and age are all major factors affecting the duration and magnitude of excess post-exercise oxygen consumption (EPOC). In the present study, the influence of age on EPOC was studied in men of various fitness levels. Various metabolic measurements were collected for three distinct age groups, 18-25, 35-45, and 55-67 at rest and during exercise at 60% of maximal oxygen consumption until 200 ± 10 kilocalories were expended. Immediately after the exercise bout, subjects walked on the treadmill for one minute and then were seated until oxygen consumption returned to within .01 liters of the recorded resting values.Percent body fat, V02 max and exercise V02 were significantly different between age groups. The duration (23-25 minutes) and magnitude (7-11 kilocalories) of EPOC did not differ significantly between groups. However, heart rate and minute ventilation were significantly elevated above resting measurements when V02 reached resting values. In conclusion, the physiological differences associated with the aging process were not found to significantly affect the duration and magnitude of EPOC. / School of Physical Education

The rate of oxygen consumption of an organisms is influenced by rush factors as temperature, activity, body rise, Salinity, and time of day (Prosser and Brown, 1961). Temperature andsalinity are considered to be the most important environmental l factor in the liver of aquatic invertebrates (Kaune, 1564). In general, aquatic invertebrates are thermo Comforters, and their ratio of metabolics and activity are decisively affected by water temperature. The capacity to regulate ray increase or decrease as a function of temperature, and it is usually greatest at a near-optimum temperature (Kinne, 1963).

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No description available.

By immumolabeling and electronmicroscopy, the subcellular localization of GmPAP3 has been proved to be mainly localized in mitochondria, a primary site for ROS production. Ectopic expression of GmPAP3 in transgenic tobacco BY-2 cells mimicked the protective effects exhibited by the antioxidant ascorbic acid by: (1) increase the percentage of cells with active mitochondria; (2) reduce the percentage of dead cells; and (3) lower the accumulation of ROS under NaCl and osmotic stress treatments. However, when ectopically express a truncated GmPAP3 with the mitochondria transit peptide removed, such protective effect was not observed. This provides evidences on the significance of mitochondria localization to the physiological function of GmPAP3. In addition, when GmPAP3 transgenic Arabidopsis thaliana seedlings were subjected to NaCl, osmotic stress, and oxidative stress treatments, the growth performance of the transgenic lines was significantly better than the wild type. To summarize, these studies has demonstrate that the mitochondrial localized GmPAP3 may play a role in stress tolerance by enhancing ROS scavenging. / Mitochondrion is one of the major sites for the production of reactive oxygen species (ROS). Abiotic stresses such as salinity and osmotic stress can cause oxidative damage to organelle membranes due to excess accumulation of ROS. The inducibility of GmPAP3 gene expression by salinity and oxidative stresses and the putative mitochondrial localization of GmPAP3 prompt us to further investigate the possible physiological roles of GmPAP3 under abiotic stress-induced oxidative stress. / My Ph.D. study has been focused on the detailed functional analysis of the GmPAP3 gene. The objectives of my research include: (i) to verified the subcellular localization of GmPAP3; (ii) to investigate the physiological functions of GmPAP3 under NaC1 and osmotic stress in both cellular level and in planta level. and (iii) to examine the significance of mitochondria] localization of GmPAP3 in relationship to its protective roles. / Purple acid phosphatases (PAPs) represent a diverse group of acid phosphatases in animals and plants. While the mammalian PAPs were found to be related to Reactive Oxygen Species (ROS) evolution in important physiological functions, the roles of plant PAPs remain largely unknown. / Recently, we have isolated a novel PAP-like gene (GmPAP3) from soybean that is induced by NaC1 and oxidative stresses. Subcellular localization prediction programs suggested that GmPAP3 may be a novel PAP that localized in mitochondria. Most other PAPs are extracellularly located and membrane localization of PAPs was only verified in a few cases. / by Li, Wing Yen Francisca. / "December 2009." / Adviser: Lam Hon-Ming. / Source: Dissertation Abstracts International, Volume: 72-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 123-134). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

o,o???-Dityrosine (dityrosine), an oxidation product of tyrosine produced by reaction between tyrosyl radicals, is becoming established as a biomarker of free radical oxidative protein damage in vivo. Attempts to measure dityrosine concentrations in various physiological and pathological systems have produced varied and often contradictory results. Dityrosine concentrations in urine, plasma, cerebrospinal fluid (CSF) and brain tissue varying over three orders of magnitude have been reported, together with inconsistent claims of significant dityrosine elevation in several ageing-related pathologies. Some of these findings have contributed to the implication of free radical activity in the pathology of several neurodegenerative disorders, vascular and ocular abnormalities and in phagocyte response to infection. The aim of this study was to test the hypothesis that dityrosine levels are elevated in ageing and ageing-related disease. The study also aims to determine the utility of dityrosine measurement as an index of oxidative damage, and elucidate possible explanations for the inconsistent levels reported. An assay for the quantification of dityrosine was developed using capillary HPLC with electrospray tandem quadrupole mass spectrometry (HPLC-MS/MS). The assay was highly specific for dityrosine and has the highest absolute sensitivity for dityrosine of any method reported to date, with a detection limit of 3 femtomoles of dityrosine on-column. Urine samples from volunteers of different age and from hospital patients with various pathologies were analysed. Plasma protein hydrolysates from control, Alzheimer???s and stroke subjects were analysed, together with hydrolysates of post mortem brain tissue from Alzheimer???s and control subjects. Urinary dityrosine level is elevated in states of acute infection and inflammation, but does not correlate with age or chronic disease. Protein dityrosine in four sections of Alzheimer???s brain was not significantly different from control sections. Dityrosine was present in human plasma and tissue proteins at approximately 5-35 residues per million tyrosine residues, and in normal urine at 5-25 micromol/mol creatinine or 20-200 nM. Most of the discrepancies in the literature relate to inadequate specificity of the analytical method. Interpretation of published data with critical appraisal of measurement technology specificity is essential in developing an accurate understanding of the role of free radicals in ageing and disease.