Journal articles on the topic 'Active oxygen in the body'
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Stabentheiner, Auton, Jutta Vollmann, Helmut Kovac, and Karl Crailsheim. "Oxygen consumption and body temperature of active and resting honeybees." Journal of Insect Physiology 49, no. 9 (September 2003): 881–89. http://dx.doi.org/10.1016/s0022-1910(03)00148-3.
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Rubalcaba, Juan G., Wilco C. E. P. Verberk, A. Jan Hendriks, Bart Saris, and H. Arthur Woods. "Oxygen limitation may affect the temperature and size dependence of metabolism in aquatic ectotherms." Proceedings of the National Academy of Sciences 117, no. 50 (November 30, 2020): 31963–68. http://dx.doi.org/10.1073/pnas.2003292117.
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Both oxygen and temperature are fundamental factors determining metabolic performance, fitness, ecological niches, and responses of many aquatic organisms to climate change. Despite the importance of physical and physiological constraints on oxygen supply affecting aerobic metabolism of aquatic ectotherms, ecological theories such as the metabolic theory of ecology have focused on the effects of temperature rather than oxygen. This gap currently impedes mechanistic models from accurately predicting metabolic rates (i.e., oxygen consumption rates) of aquatic organisms and restricts predictions to resting metabolism, which is less affected by oxygen limitation. Here, we expand on models of metabolic scaling by accounting for the role of oxygen availability and temperature on both resting and active metabolic rates. Our model predicts that oxygen limitation is more likely to constrain metabolism in larger, warmer, and active fish. Consequently, active metabolic rates are less responsive to temperature than are resting metabolic rates, and metabolism scales to body size with a smaller exponent whenever temperatures or activity levels are higher. Results from a metaanalysis of fish metabolic rates are consistent with our model predictions. The observed interactive effects of temperature, oxygen availability, and body size predict that global warming will limit the aerobic scope of aquatic ectotherms and may place a greater metabolic burden on larger individuals, impairing their physiological performance in the future. Our model reconciles the metabolic theory with empirical observations of oxygen limitation and provides a formal, quantitative framework for predicting both resting and active metabolic rate and hence aerobic scope of aquatic ectotherms.
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Davies, Ronald W., and V. Kalarani. "Influence of Overwintering Stresses on Respiration Throughout the Life History of the Freshwater Leech, Nephelopsis obscura." Canadian Journal of Fisheries and Aquatic Sciences 50, no. 4 (April 1, 1993): 841–45. http://dx.doi.org/10.1139/f93-096.
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The effects of overwintering stresses (low temperature, low oxygen concentration) on the life history patterns of activity-specific oxygen consumption by Nephelopsis obscura were determined using a flow-through respirometer system and compared with leeches hatched and maintained under summer conditions. While resting and active oxygen consumption increased with body dry weight, weight-specific resting (Rm) and active (Ra) oxygen consumption and aerobic scope (AS) decreased with increase in body weight in both winter and summer N. obscura. Rm in winter leeches was higher than in summer leeches, probably reflecting the higher metabolic costs of tissue repair and maintenance after winter stresses. Although Ra and AS in winter leeches were initially lower than in summer leeches, by stage 4, compensation in winter leeches was complete and by stage 6, over-compensation occurred. The effects of overwintering on oxygen consumption and AS persisted throughout the life history and help explain some of the differences in allocation of energy storage observed in winter and summer leeches.
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Froget, G., P. J. Butler, Y. Handrich, and A. J. Woakes. "Heart rate as an indicator of oxygen consumption: influence of body condition in the king penguin." Journal of Experimental Biology 204, no. 12 (June 15, 2001): 2133–44. http://dx.doi.org/10.1242/jeb.204.12.2133.
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SUMMARY The use of heart rate to estimate field metabolic rate has become a more widely used technique. However, this method also has some limitations, among which is the possible impact that several variables such as sex, body condition (i.e. body fat stores) and/or inactivity might have on the relationship between heart rate and rate of oxygen consumption. In the present study, we investigate the extent to which body condition can affect the use of heart rate as an indicator of the rate of oxygen consumption. Twenty-two breeding king penguins (Aptenodytes patagonicus) were exercised on a variable-speed treadmill. These birds were allocated to four groups according to their sex and whether or not they had been fasting. Linear regression equations were used to describe the relationship between heart rate and the rate of oxygen consumption for each group. There were significant differences between the regression equations for the four groups. Good relationships were obtained between resting and active oxygen pulses and an index of the body condition of the birds. Validation experiments on six courting king penguins showed that the use of a combination of resting oxygen pulse and active oxygen pulse gave the best estimate of the rate of oxygen consumption V̇O2. The mean percentage error between predicted and measured V̇O2 was only +0.81% for the six birds. We conclude that heart rate can be used to estimate rate of oxygen consumption in free-ranging king penguins even over a small time scale (30min). However, (i) the type of activity of the bird must be known and (ii) the body condition of the bird must be accurately determined. More investigations on the impact of fasting and/or inactivity on this relationship are required to refine these estimates further.
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KANG, SEUNG-ROK, YOUNG-CHOON LEE, CHUL-UN HONG, CHANG HO YU, and TAE-KYU KWON. "THE EFFECT OF MUSCLE STRENGTH AND AEROBIC FUNCTION IN THE ELDERLY ACCORDING TO EXERCISE LOAD PATTERN USING INDOOR SMALL CYCLING SYSTEM." Journal of Mechanics in Medicine and Biology 18, no. 08 (December 2018): 1840040. http://dx.doi.org/10.1142/s0219519418400407.
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We were investigating the muscle strength and aerobic function effect on the aged according to active and passive load using compact cycle system. We recruited twenty old participants and they performed shoulder rotating, upper cycling and lower cycling exercise. We measured the muscular activity, respiratory gas analysis and body heat. The result of muscular activity showed that the passive load could cause muscular activity at 15.4–65.9% compared to active load. We thought that the passive exercise could provide the prevention of spasticity and maintain effect of remaining muscle function in the elderly by caused muscular activity over 50%. The result of oxygen consumption showed that it is the active exercise that used the bigger oxygen consumption at 42.4% during lower cycling. We thought that the active exercise used the big muscles of lower limbs including trunk muscles during lower cycling. The result of body temperature showed that it rises with increase in oxygen consumption and heart rate, and it increased the bigger for lower cycling. The foundation of this study could apply to fundamental research for developing exercise load of indoor rehabilitation exercise system with convenience and easy use to the elderly.
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Livak, P. E., Yu V. Poluhin, and A. V. Steshуts. "Active recreation: types and varieties of active tourism and their essence." Scientific Journal of National Pedagogical Dragomanov University. Series 15. Scientific and pedagogical problems of physical culture (physical culture and sports), no. 7(152) (July 30, 2022): 79–83. http://dx.doi.org/10.31392/npu-nc.series15.2022.7(152).19.
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This article discusses various types of active tourism and analyzes their features. The necessity to go in for active sports, regardless of age and physical fitness, has been substantiated. It was revealed that tourist trips play an important role in the system of general training and hardening. Active tourism has many varieties, which allows you to practice at any time of the year. It was found that active tourism fosters moral and volitional attitudes of a person, and also improves his physical form and psychological state. Active tourism allows people to adapt to different conditions, travel long distances without feeling tired, and leave their comfort zone. After practicing active tourism, endurance, stamina, endurance of the body improves, due to which any physical work is done easily, and the body after it recovers faster. The work of the cardiovascular and respiratory systems improves, and oxygen is effectively used by the tissues of the body, muscles are strengthened and grown. Active tourism contributes to the improvement of the mental state. Such people have a much lower risk of depression. After class, they are more collected, patient, restrained and calm. Activities in active tourism prolong a person's active life even after retirement. Hiking trips are not only prevention, but can cure various diseases. It was found that real health is achieved through the gradual accustoming of the body to changes in the environment. Active tourism is an effective means of forming, developing and improving a healthy and tempered person. A high level of development of motor abilities underlies the success of mastering various motor actions, which is an important component of health indicators. Active tourism contains skills, abilities and knowledge that can be used in everyday life, it is also useful for the prevention of diseases of the cardiovascular system, respiratory tract, colds. In the process of regular training, various motor abilities are developed based on the age characteristics of a person: speed of movements, coordination, endurance and flexibility; vital skills are acquired, muscle strength increases, etc. Active tourism broadens one's horizons, enriches spiritual life and is an excellent means for learning about the world around and developing one’s body.
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Chung, Young-Hoon, Soo Jin Kim, Dong Young Chung, Hee Young Park, Yung-Eun Sung, Sung Jong Yoo, and Jong Hyun Jang. "Third-body effects of native surfactants on Pt nanoparticle electrocatalysts in proton exchange fuel cells." Chemical Communications 51, no. 14 (2015): 2968–71. http://dx.doi.org/10.1039/c4cc09019e.
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The third-body effect of oleylamine could enhance the oxygen reduction reaction of Pt nanoparticles in the presence of specifically adsorbed anions despite the quite small electrochemical surface active area.
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Jabbour, Georges, Melanie Henderson, Angelo Tremblay, and Marie Eve Mathieu. "Aerobic Fitness Indices of Children Differed Not by Body Weight Status but by Level of Engagement in Physical Activity." Journal of Physical Activity and Health 12, no. 6 (June 2015): 854–60. http://dx.doi.org/10.1123/jpah.2013-0337.
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Objective:Moderate-to-vigorous physical activity (MVPA) improves aerobic fitness in children, which is usually assessed by maximal oxygen consumption. However, other indices of aerobic fitness have been understudied.Methods:To compare net oxygen (VO2net), net energy consumption (Enet), net mechanical efficiency (MEnet), and lipid oxidation rate in active and inactive children across body weight statuses.Design:The sample included normal-weight, overweight, and obese children of whom 44 are active (≥30 min of MVPA/d) and 41 are inactive (<30 min of MVPA/d). VO2net, Enet, MEnet and lipid oxidation rate were determined during an incremental maximal cycling test.Results:Active obese participants had significantly lower values of VO2net and Enet and higher MEnet than inactive obese participants at all load stages. In addition, active obese participants showed a significantly higher lipid oxidation rate compared with inactive obese and active overweight and normal-weight participants. VO2net, Enet, and MEnet were similar across active children, regardless of body weight status.Conclusion:Thirty minutes or more of MVPA per day is associated with a potentiation of aerobic fitness indicators in obese prepubertal children. Moreover, the indices of aerobic fitness of inactive obese children are significantly different from those of active obese and nonobese ones.
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Stathokostas, Liza, John M. Kowalchuk, Robert J. Petrella, and Donald H. Paterson. "Maximal and submaximal aerobic fitness in postmenopausal women: influence of hormone-replacement therapy." Applied Physiology, Nutrition, and Metabolism 33, no. 5 (October 2008): 922–28. http://dx.doi.org/10.1139/h08-070.
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The purpose of this study was to examine whether maximal and submaximal aerobic fitness parameters (peak oxygen consumption and ventilatory threshold, respectively) are affected by hormone-replacement therapy (HRT) in moderately active postmenopausal women. Forty healthy, active, postmenopausal women (21 taking HRT, mean age 62 ± 5 years; 19 not taking HRT, mean age 62 ± 7 years) met the peak oxygen consumption criteria during a cycle ergometer test (15 W ramp) and achieved volitional fatigue. Breath-by-breath measurement was used to determine peak oxygen consumption and to estimate ventilatory threshold. There were no differences in characteristics (age, body mass, height, body mass index, leisure-time physical activity) between the non-HRT and HRT groups, nor were there any differences in responses to maximal exercise, with an observed peak oxygen consumption (mL·kg–1·min–1) of 22.9 ± 3.8 in the non-HRT group and 22.0 ± 4.7 in the HRT group. There was also no difference in submaximal aerobic capacity, with ventilatory threshold values (mL·kg–1·min–1) of 16.7 ± 3.4 in the non-HRT group and 15.6 ± 3.2 in the HRT group. In a sample of healthy moderately active postmenopausal women, there was no difference in maximal or submaximal aerobic fitness parameters beteen the HRT and non-HRT groups.
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Willems, Mark E. T., Milena Banic, Roseanna Cadden, and Lara Barnett. "Enhanced Walking-Induced Fat Oxidation by New Zealand Blackcurrant Extract Is Body Composition-Dependent in Recreationally Active Adult Females." Nutrients 14, no. 7 (April 1, 2022): 1475. http://dx.doi.org/10.3390/nu14071475.
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New Zealand blackcurrant (NZBC) extract enhanced cycling-induced fat oxidation in female endurance athletes. We examined in recreationally active females the effects of NZBC extract on physiological and metabolic responses by moderate-intensity walking and the relationship of fat oxidation changes with focus on body composition parameters. Twelve females (age: 21 ± 2 y, BMI: 23.6 ± 3.1 kg·m−2) volunteered. Bioelectrical bioimpedance analysis was used for body composition measurements. Resting metabolic equivalent (1-MET) was 3.31 ± 0.66 mL·kg−1·min−1. Participants completed an incremental walking test with oxygen uptake measurements to individualize the treadmill walking speed at 5-MET. In a randomized, double-blind, cross-over design, the 30 min morning walks were in the same phase of each participant’s menstrual cycle. No changes by NZBC extract were observed for walking-induced heart rate, minute ventilation, oxygen uptake, and carbon dioxide production. NZBC extract enhanced fat oxidation (10 responders, range: 10–66%). There was a significant correlation for changes in fat oxidation with body mass index; body fat% in legs, arms, and trunk; and a trend with fat oxidation at rest but not with body mass and habitual anthocyanin intake. The NZBC extract responsiveness of walking-induced fat oxidation is body composition-dependent and higher in young-adult females with higher body fat% in legs, arms, and trunk.
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Stroud, Leah C., William E. Amonette, and Terry L. Dupler. "Metabolic responses of upper-body accelerometer-controlled video games in adults." Applied Physiology, Nutrition, and Metabolism 35, no. 5 (October 2010): 643–49. http://dx.doi.org/10.1139/h10-058.
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Historically, video games required little physical exertion, but new systems utilize handheld accelerometers that require upper-body movement. It is not fully understood if the metabolic workload while playing these games is sufficient to replace routine physical activity. The purpose of this study was to quantify metabolic workloads and estimate caloric expenditure while playing upper-body accelerometer-controlled and classic seated video games. Nineteen adults completed a peak oxygen consumption treadmill test followed by an experimental session where exercising metabolism and ventilation were measured while playing 3 video games: control (CON), low activity (LOW) and high activity (HI). Resting metabolic measures (REST) were also acquired. Caloric expenditure was estimated using the Weir equation. Mean oxygen consumption normalized to body weight for HI condition was greater than LOW, CON, and REST. Mean oxygen consumption normalized to body weight for LOW condition was also greater than CON and REST. Mean exercise intensities of oxygen consumption reserve for HI, LOW, and CON were 25.8% ± 5.1%, 6.4% ± 4.8%, and 0.8% ± 2.4%, respectively. Estimated caloric expenditure during the HI was significantly related to aerobic fitness, but not during other conditions. An active video game significantly elevated oxygen consumption and heart rate, but the increase was dependent on the type of game. The mean oxygen consumption reserve during the HI video game was below recommended international standards for moderate and vigorous activity. Although upper-body accelerometer-controlled video games provided a greater exercising stimulus than classic seated video games, these data suggest they should not replace routine moderate or vigorous exercise.
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Danek, Natalia, Kamil Michalik, Rafał Hebisz, and Marek Zatoń. "Influence of Warm-Up Prior to Incremental Exercise Test on Aerobic Performance in Physically Active Men." Polish Journal of Sport and Tourism 26, no. 3 (September 1, 2019): 9–13. http://dx.doi.org/10.2478/pjst-2019-0014.
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AbstractIntroduction. The aim of the study was to verify the influence of warm-up before a ramp incremental exercise test with linearly increasing loads on the maximal values of physiological variables which determine performance.Material and methods. Thirteen healthy and physically active male students (age = 23.3 ± 1.5 years, body height = 179.1 ± 8.6 cm and body mass = 79.5 ± 9.1 kg) completed a cross-over comparison of two incremental exercise test interventions – an incremental exercise test with a 15-minute warm-up at an intensity of 60% of the maximal oxygen uptake obtained in the first incremental exercise test and the same test without warm-up.Results. The peak values of physiological variables were statistically significantly higher for the incremental exercise test with warm-up, the differences between tests being 2.66% for peak power output (p = 0.039, t = 2.312, ES = 0.24), 7.75% for peak oxygen uptake (p = 0.000, t = 5.225, ES = 0.56), 7.72% for peak minute ventilation (p = 0.005, t = 3.346, ES = 0.53) and 1.62% for peak heart rate (p = 0.019, t = 2.690, ES = 0.60).Conclusions. Warm-up before a ramp incremental exercise test resulted in higher values of maximal oxygen uptake, maximal minute ventilation, maximal heart rate and peak power output.
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Spicer, John I., and Simon A. Morley. "Will giant polar amphipods be first to fare badly in an oxygen-poor ocean? Testing hypotheses linking oxygen to body size." Philosophical Transactions of the Royal Society B: Biological Sciences 374, no. 1778 (June 17, 2019): 20190034. http://dx.doi.org/10.1098/rstb.2019.0034.
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It has been suggested that giant Antarctic marine invertebrates will be particularly vulnerable to declining O 2 levels as our ocean warms in line with current climate change predictions. Our study provides some support for this oxygen limitation hypothesis, with larger body sizes being generally more sensitive to O 2 reductions than smaller body sizes. However, it also suggests that the overall picture is a little more complex. We tested predictions from three different, but overlapping, O 2 -related hypotheses accounting for gigantism, using four Antarctic amphipod species encompassing a wide range of body sizes. We found a significant effect of body size, but also of species, in their respiratory responses to acutely declining O 2 tensions. The more active lifestyle of intermediate-sized Prostebbingia brevicornis was supported by a better respiratory performance than predicted by the oxygen limitation hypothesis alone, but consistent with the symmorphosis hypothesis. We suggest that giant polar amphipods are likely to be some of the first to fare badly in an O 2 -poor ocean. However, the products of past evolutionary innovation, such as respiratory pigments that enhance O 2 -transport and novel gas exchange structures, may in some species offset any respiratory disadvantages of either large or small body size. This article is part of the theme issue ‘Physiological diversity, biodiversity patterns and global climate change: testing key hypotheses involving temperature and oxygen’.
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Smith, Abbie E., Christopher M. Lockwood, Jordan R. Moon, Kristina L. Kendall, David H. Fukuda, Sarah E. Tobkin, Joel T. Cramer, and Jeffrey R. Stout. "Physiological effects of caffeine, epigallocatechin-3-gallate, and exercise in overweight and obese women." Applied Physiology, Nutrition, and Metabolism 35, no. 5 (October 2010): 607–16. http://dx.doi.org/10.1139/h10-056.
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The aim of this study was to evaluate the combined effects of a 10-week exercise program with ingestion of caffeine and epigallocatechin-3-gallate (EGCG) on body composition, cardiovascular fitness, and strength in overweight and obese women. In a double-blind, placebo-controlled approach, overweight and obese women (n = 27) were randomly assigned to treatment groups with exercise (an active-supplementing group with exercise (EX-Act) and a placebo group with exercise (EX-PL)) or without exercise (an active-supplementing group without exercise (NEX-Act) and a placebo group without exercise (NEX-PL)). All participants consumed 1 drink per day for 10 weeks; EX-Act and EX-PL participated in a concurrent endurance and resistance training program. Changes in body composition were assessed using a 4-compartment model. Changes in muscle mass (MM) were evaluated using a DXA-derived appendicular lean–soft tissue equation. There was a significant time × treatment interaction for MM (p = 0.026) and total cholesterol (TC) (p = 0.047), and a significant time × training interaction for peak oxygen consumption (p = 0.046) and upper-body and lower-body strength (p < 0.05). Significant differences between the EX groups and NEX groups for percentage change in MM and peak oxygen consumption, and upper-body and lower-body strength, were revealed. Clinical markers for hepatic and renal function revealed no adverse effects. TC significantly decreased for the active-supplementing groups (EX-Act, NEX-Act). The current study suggests that implementing a caffeine–EGCG-containing drink prior to exercise may improve MM, fitness, and lipid profiles in overweight women.
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Madueno, Maria C., Vincent J. Dalbo, Joshua H. Guy, Kate E. Giamarelos, Tania Spiteri, and Aaron T. Scanlan. "Reduced Fatigue in Passive Versus Active Recovery: An Examination of Repeated-Change-of-Direction Sprints in Basketball Players." International Journal of Sports Physiology and Performance 13, no. 8 (September 1, 2018): 1034–41. http://dx.doi.org/10.1123/ijspp.2017-0831.
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Purpose: To investigate the physiological and performance effects of active and passive recovery between repeated-change-of-direction sprints. Methods: Eight semiprofessional basketball players (age: 19.9 [1.5] y; stature: 183.0 [9.6] cm; body mass: 77.7 [16.9] kg; body fat: 11.8% [6.3%]; and peak oxygen consumption: 46.1 [7.6] mL·kg−1·min−1) completed 12 × 20-m repeated-change-of-direction sprints (Agility 5-0-5 tests) interspersed with 20 seconds of active (50% maximal aerobic speed) or passive recovery in a randomized crossover design. Physiological and perceptual measures included heart rate, oxygen consumption, blood lactate concentration, and rating of perceived exertion. Change-of-direction speed was measured during each sprint using the change-of-direction deficit (CODD), with summed CODD time and CODD decrement calculated as performance measures. Results: Average heart rate (7.3 [6.4] beats·min−1; P = .010; effect size (ES) = 1.09; very likely) and oxygen consumption (4.4 [5.0] mL·kg−1·min−1; P = .12; ES = 0.77; unclear) were moderately greater with active recovery compared with passive recovery across sprints. Summed CODD time (0.87 [1.01] s; P = .07; ES = 0.76, moderate; likely) and CODD decrement (8.1% [3.7%]; P < .01; ES = 1.94, large; almost certainly) were higher with active compared with passive recovery. Trivial–small differences were evident for rating of perceived exertion (P = .516; ES = 0.19; unclear) and posttest blood lactate concentration (P = .29; ES = 0.40; unclear) between recovery modes. Conclusions: Passive recovery between repeated-change-of-direction sprints may reduce the physiological stress and fatigue encountered compared with active recovery in basketball players.
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Balic, Myriam Guerra, Eufemia Cuadrado Mateos, Carolina Geronimo Blasco, and Bo Fernhall. "Physical Fitness Levels of Physically Active and Sedentary Adults with Down Syndrome." Adapted Physical Activity Quarterly 17, no. 3 (July 2000): 310–21. http://dx.doi.org/10.1123/apaq.17.3.310.
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The purpose was to compare physical fitness of two groups of adults with Down syndrome, one active group of Special Olympians (9 males, 4 females), and one sedentary group (5 males, and 2 females). The active group had trained for an average of 4.9 hr per week for a minimum of 1 year for Special Olympics competitions. Participants underwent laboratory testing, including (a) treadmill test to determine peak oxygen uptake; (b) isometric strength tests of handgrip, lower back, and quadriceps; (c) explosive power; and (d) body composition. Peak oxygen consumption and muscle strength were significantly greater in the active group. Although crossectional, these findings suggest that long term exercise training, at a greater than previously reported weekly training load, may enhance physical fitness in individuals with Down syndrome.
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Carmeli, Eli, Pini Orbach, David T. Lowenthal, Joav Merrick, and Raymond Coleman. "Long-Term Effects of Activity Status in the Elderly on Cardiorespiratory Capacity, Blood Pressure, Blood Lipids, and Body Composition: A Five-Year Follow-Up Study." Scientific World JOURNAL 3 (2003): 751–67. http://dx.doi.org/10.1100/tsw.2003.66.
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It is generally recognized that physical activity levels in the elderly do not remain constant over time, and typically there is a marked reduction in physical activities in the elderly. The long-term benefits of regular physical training programs in the elderly are still not fully understood. This is a study of 55 elderly healthy subjects (over 65 years old) and re-evaluated for the effects of different physical activity patterns (sedentary, moderately active, and highly active) on several physiological parameters (pre- and post-training) after a 5-year period (5.30 ± 1.14 years). Measurements included: body composition, blood lipid profiles, resting systolic and diastolic blood pressure, maximal oxygen uptake, and pulmonary function. Results indicated a larger decrease in maximal oxygen uptake (VO2max) in the group of elderly sedentary individuals (1.5 ± 0.5 l/min) compared to the moderately active (1.7 ± 0.6 l/min) and the highly active groups (1.9 ± 0.4 l/min). An active lifestyle was not sufficient to increase the physiological function of an individual.This study could not clearly demonstrate favorable differences for the physically active groups over the sedentary group with regard to several important physiological factors over the 5-year follow-up and it appears that the recommendation for, and the initiation of, adopting active lifestyles may not be sufficient on their own to significantly increase an individual's physiological functioning.
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Gizinger, O. "Restoring adaptive potential and active longevity using ginseng phytomicrospheres." Terapevt (General Physician), no. 6 (June 1, 2020): 53–58. http://dx.doi.org/10.33920/med-12-2006-07.
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Medicines with adaptogenic activity, containing ginseng extractive substances as an active ingredient are widely used in pharmacology. Biologically active products obtained using innovative technology using Phytomicrospheres® are relevant in strategies for increasing adaptation, overcoming chronic stress, anti-age. The article presents an analysis of the effectiveness of the use of a plant complex based on the active ingredients of the ginseng plant, using phytomicrosphering technology, which ensures maximum assimilation of all components by the body. Having a high bioavailability, the complex has a beneficial effect on the cardiovascular system, improves blood circulation, stimulates the supply of oxygen to brain tissue, prevents premature aging, improves performance and intellectual activity, and improves memory and concentration.
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Beebe, David C., Nancy M. Holekamp, Carla Siegfried, and Ying-Bo Shui. "Vitreoretinal influences on lens function and cataract." Philosophical Transactions of the Royal Society B: Biological Sciences 366, no. 1568 (April 27, 2011): 1293–300. http://dx.doi.org/10.1098/rstb.2010.0228.
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The lens is composed of a thin metabolically active outer layer, consisting of epithelial and superficial fibre cells. Lying within this outer shell are terminally differentiated, metabolically inactive fibre cells, which are divided into an outer cortex and central nucleus. Mature fibre cells contain a very high protein concentration, which is important for the transparency and refractive power of the lens. These proteins are protected from oxidation by reducing substances, like glutathione, and by the low-oxygen environment around the lens. Glutathione reaches the mature fibre cells by diffusing from the metabolically active cells at the lens surface. With age, the cytoplasm of the nucleus becomes stiffer, reducing the rate of diffusion and making nuclear proteins more susceptible to oxidation. Low pO 2 is maintained at the posterior surface of the lens by the physical and physiological properties of the vitreous body, the gel filling the space between the lens and the retina. Destruction or degeneration of the vitreous body increases exposure of the lens to oxygen from the retina. Oxygen reaches the lens nucleus, increasing protein oxidation and aggregation and leading to nuclear cataract. We suggest that maintaining low pO 2 around the lens should prevent the formation of nuclear cataracts.
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Lambert, Charles Paul. "Whole Body Fat Free Mass and Vo2peak in Recreationally Active Men and Women." Aerospace Medicine and Human Performance 91, no. 2 (February 1, 2020): 102–5. http://dx.doi.org/10.3357/amhp.5448.2020.
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BACKGROUND: Vo2peak has traditionally been thought to be regulated by cardiac output and arteriovenous-oxygen difference. A “muscle-centric” view suggests the cardiovascular system is secondarily responsive to the primary driver: active muscle mass.METHODS: A total of 19 recreationally active men (N = 10) and women (N = 9) performed a Vo2peak test, a Vo2peak verification test on an electrically braked cycle ergometer on the same day, and a hydrostatic weighing test to assess fat free mass after providing written informed consent.RESULTS: Vo2peak was significantly higher in men (3.74 ± 0.6 L · min−1) than women (2.22 ± 0.30 L · min−1). Whole body fat free mass explained 91% of the variability in Vo2peak (R2 = 0.91) in the men and women combined, 81% of the variability in Vo2peak in men alone, and 46% of the variability in Vo2peak in women alone. None of these subjects were highly trained.DISCUSSION: Fat free mass, a surrogate for muscle mass, was the primary predictor of Vo2peak in this group of recreationally active men and women. Therefore, it appears that whole body fat free mass (a surrogate for muscle mass) is the primary driver for Vo2peak in these recreationally active men and women. These data have implications as to the type of training NASA personnel should be undertaking: resistance training as opposed to aerobic training.Lambert CP. Whole body fat free mass and Vo2peak in recreationally active men and women. Aerosp Med Hum Perform. 2020; 91(2):102–105.
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Racil, Ghazi, Hassane Zouhal, Wassim Elmontassar, Abderraouf Ben Abderrahmane, Maysa Vieira De Sousa, Karim Chamari, Mohamed Amri, and Jeremy B. Coquart. "Plyometric exercise combined with high-intensity interval training improves metabolic abnormalities in young obese females more so than interval training alone." Applied Physiology, Nutrition, and Metabolism 41, no. 1 (January 2016): 103–9. http://dx.doi.org/10.1139/apnm-2015-0384.
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The aim of this study was to compare the effects of 12 weeks of high-intensity interval training (HIIT) with the effects of 12 weeks of plyometric exercise combined with HIIT (P+HIIT) on anthropometric, biochemical, and physical fitness data in young obese females. Sixty-eight participants (age, 16.6 ± 1.3 y; body mass, 82.8 ± 5.0 kg; body fat, 39.4% ± 3.3%; body mass index z score, 2.9 ± 0.4) were assigned to 1 of 3 groups: HIIT (2 blocks per session of 6–8 bouts of 30-s runs at 100% velocity at peak oxygen uptake, with 30-s active recovery between bouts at 50%velocity at peak oxygen uptake (n = 23)); P+HIIT (2 blocks per session of 3 different 15-s plyometric exercises with 15-s passive recoveries, totaling 2 min for each plyometric exercise + the same HIIT program (n = 26)); or control (no exercise (n = 19)). Anthropometric (body mass, body mass index z score, body fat, lean body mass, and waist circumference), biochemical (plasma glucose, insulin, leptin and adiponectin concentrations, leptin/adiponectin ratio, and homeostasis model assessment of insulin resistance (HOMA-IR)), physical fitness (peak oxygen uptake, velocity at peak oxygen uptake, squat jump, and countermovement jump performances), and energy intake data were collected. Both training programs improved the anthropometric, biochemical, and physical fitness variables. However, the P+HIIT program induced greater improvements than did the HIIT program in lean body mass (+3.0% ± 1.7%), plasma glucose and leptin concentrations (–11.0% ± 4.7% and –23.8% ± 5.8%, respectively), plasma leptin/adiponectin ratio (–40.9% ± 10.9%), HOMA-IR (–37.3% ± 6.2%), and squat jump performance (22.2% ± 7.5%). Taken together, these findings suggest that adding plyometric exercises to a HIIT program may be more beneficial than HIIT alone in obese female adolescents.
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Idris, Fathiyah, Zaid Nailul Murad, Boon Chye Gan, Khairul Bariah Noh, Yeoh Xing Yi, Ong Fei Ming, Ng Siew Peng, Zakaria Zahirrudin, and Goh Bee See. "Complicated Paediatric Bronchial Foreign Body: A Novel Extraction Technique." Bangladesh Journal of Otorhinolaryngology 27, no. 2 (November 1, 2021): 177–83. http://dx.doi.org/10.3329/bjo.v27i2.56365.
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A paediatric bronchoscopy procedure for foreign body inhalation is indeed a highly challenging procedure due to multiple risk factors such as lower physiological functional residual capacity and adverse pulmonary function effects by anaesthetic agents in addition to concurrent active lungs infection. Here we elucidate a novel technique of foreign body removal located at the distal airway in a paediatric patient and in a situation where a paediatric flexible bronchoscopy with built-in working channel is not available. A 1-year 7-months-old boy presented with acute respiratory distress syndrome following a one-week history of active respiratory infection. On examination, he was tachypnoeic with audible soft inspiratory stridor and intermittent barking cough despite being supplemented with 3 liters /minute oxygen mask. Chest x-ray showed right upper lobe collapse. He was referred to the otorhinolaryngology team after a suspicious history of foreign body aspiration obtained from his mother. Bedside flexible nasopharyngolaryngoscopy showed granulation tissue at the junction of laryngeal surface of epiglottis and anterior commissure. He underwent emergency direct laryngoscopy, tracheoscopy, bronchoscopy, excision of granulation tissue and removal of foreign body under general anaesthesia. Herein, some of complicated bronchoscopy demand critical thinking of alternative or modified techniques to achieve a successful and safe surgery. Bangladesh J Otorhinolaryngol 2021; 27(2): 177-183
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Falz, Roberto, Sven Fikenzer, Stephan Hoppe, and Martin Busse. "Normal Values of Hemoglobin Mass and Blood Volume in Young, Active Women and Men." International Journal of Sports Medicine 40, no. 04 (February 21, 2019): 236–44. http://dx.doi.org/10.1055/a-0826-9235.
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AbstractHemoglobin mass (Hbmass) and total blood volume (BV) determine the oxygen content in the blood. Varying anthropometric values are used to standardize blood volume and Hbmass. The aim of this study was to create normal values and to evaluate an anthropometric reference for Hbmass and BV. One hundred healthy young subjects participated in this study (50 women: 20.9±2.0 yr; 50 men: 23.2±2.9 yr). The Hbmass was measured twice by using a CO rebreathing method. The BV was calculated from the Hbmass, Hb concentration and hematocrit values. The lean body mass (LBM) was measured by a bio-impedance analysis. Women had a significant lower Hbmass per kg LBM compared with that of men (13.6±1.3 g vs. 16.1±1.7 g; p<0.0001). The BV per kg LBM tended to be lower in women than in men (105.3±8.4 ml vs. 108.7±9.0 ml; p=0.0548). LBM had the best correlation with Hbmass (r=0.9274) and BV (0.9233) when considering the entire study group. Normal values of Hbmass and BV could be potentially useful for fluid management and contribute to the diagnosis of blood disorders. For normalization and assessment of measured BV and Hbmass, lean body mass should be prioritized in future studies instead of body weight or body surface area.
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Ramkrapes, Ana Paula B., Renata G. Duft, Ivan L. P. Bonfante, Keryma C. S. Mateus, Joice C. S. Trombeta, Bruno Rodrigues, Mara Patrícia T. Chacon-Mikahil, Ricardo A. Tanhoffer, and Claudia R. Cavaglieri. "Higher Physical Activity Level Improves Leptin Concentrations in Spinal Cord Injury Subjects." BioMed Research International 2021 (September 28, 2021): 1–8. http://dx.doi.org/10.1155/2021/9415253.
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The present study was designed to compare the body composition and indicators of chronic inflammatory grade, such as leptin, adiponectin, and resistin concentrations in irregularly active and active SCI subjects. Thirty-two male subjects participated in this study. They were divided into three groups: able-bodied control irregularly active (control, n = 11 ), irregularly active with SCI (SCI-IA, n = 8 ), and physically active with SCI (SCI-PA, n = 13 ). The enzyme-linked immunosorbent assay (ELISA) assessed serum concentrations of leptin, adiponectin, and resistin. All volunteers performed the maximum oxygen uptake (VO2max) test, 24 h total energy expenditure (TEE), and body composition by skinfold thicknesses. Leptin concentrations were higher in the SCI-IA group when compared to the other groups, while no significant differences were found between the SCI-PA and control cohorts. In addition, no significant differences were found among groups for serum adiponectin and resistin concentrations either. The SCI-PA group showed significantly higher values for TEE and VO2max when compared to the other groups. Percentages of body fat and circumference were decreased in the control and SCI-PA groups when compared to the SCI-IA cohort. Associations between leptin and cardiorespiratory capacity and anthropometric markers were also observed. Our findings highlight that the lack of physical activity in the SCI subjects leads to poor general physical fitness and higher levels of body adiposity, which may induce hyperleptinemia, an essential marker for cardiometabolic disorders.
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Bartfay, Wally, and Emma Bartfay. "A Case–Control Study Examining the Effects of Active Versus Sedentary Lifestyles on Measures of Body Iron Burden and Oxidative Stress in Postmenopausal Women." Biological Research For Nursing 16, no. 1 (September 19, 2013): 38–45. http://dx.doi.org/10.1177/1099800413501717.
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Approximately half of the Canadian adults have sedentary lifestyles that increase their risk of developing cardiovascular disease (CVD). Women are 10 times more likely to die from CVD than from any other disease. Their risk almost doubles with the onset of menopause, which may result in increased body iron burden and oxidative stress in sedentary women. Body iron burden may catalyze the production of cytotoxic oxygen species in vivo. We hypothesized that postmenopausal women who engage in moderate forms of aerobic exercise for at least 30 min three or more times per week would have significantly (i) lower levels of body iron burden, (ii) increased glutathione peroxidase (GPx) activity, and (iii) decreased oxidative stress in comparison to sedentary controls. An age-matched, case–control study was employed to examine the effects of active ( N = 25) versus sedentary ( N = 25) lifestyles in women aged 55–65 years on measures of body iron burden as quantified by total serum iron, transferrin saturation, and serum ferritin levels; GPx activity; and oxidative stress as quantified by 4-hydroxynonenal, malondialdehyde, and hexanal. Measures of body iron burden were significantly elevated in sedentary women in comparison to active women ( p < .001). Red cell GPx activity was higher in active women compared to sedentary women ( p < .001). Measures of oxidative stress were significantly higher in sedentary versus active women ( p < .001). These findings suggest that aerobic forms of exercise may mitigate the risk of developing CVD in postmenopausal women by improving antioxidant capacity and decreasing body iron burden.
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Fernández-Elías, Valentín E., David Tobía, Anel Recarey, Álvaro Fernández, Vicente J. Clemente-Suárez, and Silvia Burgos-Postigo. "Acute Effects of Whole-Body Electromyostimulation during a Single Maximal Strength Training Session." International Journal of Environmental Research and Public Health 19, no. 21 (October 22, 2022): 13753. http://dx.doi.org/10.3390/ijerph192113753.
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Whole-body electromyostimulation (WB-EMS) training is effective in improving training adaptation. However, WB-EMS may have side effects and contraindications that can lead to excessive muscle damage and physiological impairment. This randomized crossover study aimed to analyze the acute effects of WB-EMS on muscle damage, autonomic modulation and performance during a single maximal strength session in physically active participants. Twenty healthy and physically active participants randomly performed three maximal strength training sessions (90% 1RM) consisting of bench presses and squat exercises, with a continuous stimulus, a coordinated stimulus with concentric and eccentric phases, and without WB-EMS. Data showed no significant differences between the trials for muscle damage (blood creatine kinase levels), lactate blood levels and performance after exercise. Likewise, the heart rate, blood oxygen saturation and the rate of perceived exertion were similar during exercise between trials. The heart rate variability analysis also showed a similar autonomic response among the trials. Training with WB-EMS seemed to be safe at the observed time intervals while offering a stimulus similar to regular training in physically active participants, regardless of the delivery of the electrical stimuli. More studies are needed to assess the effectiveness of WB-EMS in improving exercise adaptations during training programs.
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Leppäranta, Matti, A. Reinart, A. Erm, H. Arst, M. Hussainov, and L. Sipelgas. "Investigation of Ice and Water Properties and Under-ice Light Fields in Fresh and Brackish Water Bodies." Hydrology Research 34, no. 3 (June 1, 2003): 245–66. http://dx.doi.org/10.2166/nh.2003.0006.
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Light transmission through ice and light conditions beneath ice have been investigated in the mild winter of the year 2000 in eight Estonian lakes arid in one brackish water basin, Santala Bay in the Gulf of Finland. A new system designed for optical measurements beneath the ice was successfully tested. In the water body the vertical profiles of photosynthetically active radiation (PAR), temperature and oxygen were mapped. The concentrations of optically active substances (dissolved organic matter, chlorophyll a, particles) were estimated for water samples and meltwater of ice samples. The PAR band albedo was 0.28-0.76 and transmittance was 1-52% for the ice/snow cover. The light field below ice was much more diffuse than in open water conditions. Euphotic depth was 0.1-5.5 m. The amount of yellow substance in lake ice is very small in comparison with the lake water; lake ice may contain a lot of particles, but their source is atmospheric fallout rather than the water body. In some lakes a depletion of oxygen was observed. There were considerable differences between the fresh and brackish water ice (structure, stratigraphy, amount of impurities), which influenced the underwater light field.
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Rydén, Magnus, Malin Hanning, and Fredrik Lind. "Oxygen Carrier Aided Combustion (OCAC) of Wood Chips in a 12 MWth Circulating Fluidized Bed Boiler Using Steel Converter Slag as Bed Material." Applied Sciences 8, no. 12 (December 18, 2018): 2657. http://dx.doi.org/10.3390/app8122657.
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The novel combustion concept Oxygen Carrier Aided Combustion (OCAC) is realized by addition of an active oxygen-carrying bed material to conventional fluidized bed boilers. The active bed material is meant to become reduced in fuel-rich parts of the boiler and oxidized in oxygen-rich parts, thus potentially providing advantages such as new mechanisms for oxygen transport in space and time. In this study, oxygen-carrier particles prepared from so called Linz-Donawitz (LD)-slag are examined as active bed material in a 12 MWth Circulating Fluidized Bed (CFB) boiler. LD-slag is the second largest by-product in steel making and is generated in the basic LD oxygen converter process. The experimental campaign lasted for two full weeks. The fuel was wood chips. LD-slag worked well from an operational point of view and no problems related to handling, agglomeration or sintering were experienced, albeit the production of fly ash increased. The boiler temperature profile suggested that fuel conversion in the main boiler body was facilitated, but the effect did not readily translate into reduced emissions from the stack. Spraying an aqueous solution of ammonium sulphate directly into the cyclone outlet with the aim of rejecting alkali metals as alkali suphates was found to solve the problems related to carbon monoxide emissions, suggesting that the problems could be due to the poor ability of LD-slag to absorb certain ash components. Use of a mixed bed consisting of 10–50 wt% LD-slag, with the remaining part being silica sand for ash absorption, also worked well. It is concluded that LD-slag could be a very cheap and readily available oxygen-carrying bed material for use in fluidized bed applications.
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Lamboley, Cédric R. H., Donald Royer, and Isabelle J. Dionne. "Effects of β-Hydroxy-β-Methylbutyrate on Aerobic-Performance Components and Body Composition in College Students." International Journal of Sport Nutrition and Exercise Metabolism 17, no. 1 (February 2007): 56–69. http://dx.doi.org/10.1123/ijsnem.17.1.56.
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The aim of this study was to determine the effects of oral β-hydroxy-β-methylbutyrate (HMB) supplementation (3 g/d) on selected components of aerobic performance and body composition of active college students. Subjects were randomly assigned to either an HMB (n = 8) or a placebo (PLA) group (n = 8) for a 5-wk supplementation period during which they underwent interval training 3 times a week on a treadmill. Aerobic-performance components were measured using a respiratory-gas analyzer. Body composition was determined using dual-energy X-ray absorptiometry. After the intervention, there were significant differences (P < 0.05) between the 2 groups in gains in maximal oxygen consumption (+8.4% for PLA and +15.5% for HMB) and in respiratory-compensation point (+8.6% for PLA and +13.4% for HMB). Regarding body composition, there were no significant differences. The authors concluded that HMB supplementation positively affects selected components of aerobic performance in active college students.
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He, Juan, Xiaomin Xu, Hainan Sun, Tengfei Miao, Meisheng Li, Shouyong Zhou, and Wei Zhou. "Participation of Lattice Oxygen in Perovskite Oxide as a Highly Sensitive Sensor for p-Phenylenediamine Detection." Molecules 28, no. 3 (January 22, 2023): 1122. http://dx.doi.org/10.3390/molecules28031122.
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The harmful effects on the human body from p-phenylenediamine (PPD) in hair dyes can cause allergies and even cancer. Therefore, it is particularly important to accurately control and detect the content of PPD in our daily products and environment. Here, a small amount of non-metallic elemental P doped in perovskite oxide of SrCoO3-δ (SC) forms a good catalytic material, SrCo0.95P0.05O3-δ (SCP), for PPD detection. The improved performance compared with that of the parent SC can be attributed to three contributing factors, including a larger amount of highly oxidative oxygen species O22-/O-, better electrical conductivity, and more active sites on the P5+-oxygen bonds of SCP. Moreover, the lattice oxygen mechanism (LOM) with highly active species of lattice O vacancies and adsorbed –OO for electrocatalytic oxidation of PPD by the SCP/GCE (glass carbon electrode) sensor is proposed in our work. More importantly, the SCP/GCE sensor exhibits good stability, a low limit of detection, and high reliability (error < 5.78%) towards PPD determination in real samples of hair dyes, suggesting the substantial research potential for practical applications.
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Raskil’dina, Gul’nara Z., Gulnur N. Sakhabutdinova, Semyon S. Zlotsky, Rimma M. Sultanova, Svetlana A. Meshcheryakova, Alina V. Shumadalova, Yulia L. Bortsova, and Ulyana Sh Kuzmina. "ANTIOXIDANT AND CYTOTOXIC ACTIVITY OF A SERIES OF O- AND S-CONTAINING MACROCYCLES." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 63, no. 3 (March 8, 2020): 82–87. http://dx.doi.org/10.6060/ivkkt.20206303.6118.
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The significant interest in the search and study of antioxidants, both natural and synthetic, is explained by the possibility of preventing these harmful effects of free radicals in the human body. The similarity of macroheterocyclic derivatives to endogenous biomolecules makes them promising for research as antioxidant agents. By the interaction of 1,3-oxoheterocycloalkanes with ethyl 2-diazo-3-oxobutanoate, previously unexplored polyfunctional oxygen and sulfur-containing macroheterocycles are obtained. The relative antioxidant activity of new macroheterocycles in two model systems: generating active forms of oxygen and modulating lipid peroxidation reaction, was revealed active forms of oxygen and described by the method of recording luminol-dependent chemiluminescence lipid peroxidation reaction. The in vitro cytotoxic activity of the studied compounds was studied on Jurkat (human T-lymphoblastic leukemia cells), HepG2 (human liver carcinoma cells), HEK293 (human embryonic kidney cells) cell lines. The data obtained indicate practical significance. So, reagents 1-7 in the active forms of oxygen generating system have anti- and prooxidative properties, and in the system modeling lipid peroxidation reaction, they show only prooxidant activity. The influence of heterocycles 1–7 on the processes of free radical oxidation was determined by the intensity of the maximum flash (Imax, у.е.) and the luminosity of light (S, у.е.). Compounds with maximum anti- (4) and prooxidative (6) properties in the active forms of oxygen generating system and reagent 3 with the highest prooxidant activity in the lipid peroxidation reaction modeling system do not possess cytotoxic activity in vitro on cell lines HEK293 and HepG2 cultured in DMEM medium (Biolot, Russia), Jurkat in RPMI medium (Biolot, Russia) in the presence of 10% fetal calf serum (Invitrogen, USA), 2 mM L-glutamine and 50 μg / ml gentamicin sulfate.
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Pluncevikj Gligoroska, Jasmina, Sanja Manchevska, Ljudmila Efremova, Lidija Todorovska, and Slobodan Nikolic. "Body composition and maximal oxygen consumption in adult soccer players in the Republic of Macedonia." Journal of Health Sciences 5, no. 3 (December 16, 2015): 85–92. http://dx.doi.org/10.17532/jhsci.2016.268.
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Introduction: The purpose of this study was to investigate the relationship between active and passive body mass components and maximal aerobic consumption (VO2max) in adult male soccer players.Methods: The study involved seven hundred (700) male soccer players, mean age 25.06 ± 4.41 years (range 18 to 35), divided in six age groups. Body composition was assessed according the anthropometric protocol by Matiegka, and relative muscle mass (MM%), bone (BM%) and fat (BF%) and absolute muscle mass (MMkg), bone (BMkg) and fat (BFkg) components were calculated. The Bruce protocol (incremental multistage treadmill test) was used for the estimation of maximal oxygen consumption.Results: Mean values of body mass components for total sample were as follows: muscle mass (MM%)= 52.75 ± 2.63%, bone mass (BM%)=16.63 ± 1.29% and body fat (BF%)=14.12 ± 1.54%. Mean VO2max was 48.89±5.17 ml/kg/minute. Relative muscle mass (MM%) showed similar values across age different groups (ANOVA: F=2.174; p=0.06) while absolute muscle mass (MMkg) showed tendency of increment with age (ANOVA: F=2.136; p=0.01). Body fat (BFkg and BF%) was statistically higher in the older groups (ANOVA F=3.737; p<0.01; ANOVA F=4.117; p<0.01). Weak positive correlation between VO2 max and muscle component (r=0.243; p<0.001) and a weak negative correlation between VO2max and body fat (r=-0.08;p<0.05) were found.Conclusions: Our results confirm the assumption that subjects with larger muscle mass have greater endurance and higher maximal oxygen consumption compared to subjects with larger body fat component.
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Davy, K. P., N. L. Miniclier, J. A. Taylor, E. T. Stevenson, and D. R. Seals. "Elevated heart rate variability in physically active postmenopausal women: a cardioprotective effect?" American Journal of Physiology-Heart and Circulatory Physiology 271, no. 2 (August 1, 1996): H455—H460. http://dx.doi.org/10.1152/ajpheart.1996.271.2.h455.
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Coronary heart disease (CHD) and cardiac sudden death (CSD) incidence accelerates after menopause, but the incidence is lower in physically active versus less active women. Low heart rate variability (HRV) is a risk factor for CHD and CSD. The purpose of the present investigation was to test the hypothesis that HRV at rest is greater in physically active compared with less active postmenopausal women. If true, we further hypothesized that the greater HRV in the physically active women would be closely associated with an elevated spontaneous cardiac baroreflex sensitivity (SBRS). HRV (both time and frequency domain measures) and SBRS (sequence method) were measured during 5-min periods of controlled frequency breathing (15 breaths/min) in the supine, sitting, and standing postures in 9 physically active postmenopausal women (age = 53 +/- 1 yr) and 11 age-matched controls (age = 56 +/- 2 yr). Body weight, body mass index, and body fat percentage were lower (P < 0.01) and maximal oxygen uptake was higher (P < 0.01) in the physically active group. The standard deviation of the R-R intervals (time domain measure) was higher in all postures in the active women (P < 0.05) as were the high-frequency, low-frequency, and total power of HRV. SBRS also was higher (P < 0.05) in the physically active women in all postures and accounted for approximately 70% of the variance in the high-frequency power of HRV (P < 0.05). The results of the present investigation indicate that physically active postmenopausal women demonstrate higher levels of HRV compared with age-matched, less active women. Furthermore, SBRS accounted for the majority of the variance in the high-frequency power of HRV, suggesting the possibility of a mechanistic link with cardiac vagal modulation of heart rate. Our findings may provide insight into a possible cardioprotective mechanism in physically active postmenopausal women.
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Laskina, O., G. Zalesskaya, and N. Mitkovskaya. "APPLICATION OF PHOTOMODIFICATION OF BLOOD USING LOW-INTENSITY OPTICAL RADIATION IN THE COMBINATION TREATMENT OF PATIENTS WITH UNSTABLE ANGINA." Emergency Cardiology and Cardiovascular Risks 5, no. 1 (2021): 1145–50. http://dx.doi.org/10.51922/2616-633x.2021.5.2.1145.
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The in vivo effect of low-intensity optical radiation (LIOR) on the blood of patients with unstable angina (UA) was studied. The integration of LIOR in the combined therapy of patients with UA proved to result in positive changes in the oxygen uptake system. Changes in the absorption spectra of the patients' blood samples, blood oxygenation characteristics, and the proportion of metabolic products were studied at all stages of light exposure. The absorption of LIOR by the blood was found to lead to its photomodification, which was manifested in changes of the partial pressure of blood gases, the content of oxyhemoglobin and the degree of saturation of hemoglobin with oxygen. LIOR affects the oxygen exchange in the body of patients with UA, changes the delivery and consumption of oxygen by tissues, initiates positive changes in the balance between the production of reactive oxygen intermediates, acting as physiologically active compounds, and their inhibition by antioxidant systems.
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Zverev, D. P., Z. M. Israfilov, A. A. Myasnikov, A. Yu Shitov, and V. I. Chernov. "Research of diver body functions’ state with different resistance to the toxic oxygen effect: prospective cohort study." Marine Medicine 8, no. 3 (October 22, 2022): 30–39. http://dx.doi.org/10.22328/2413-5747-2022-8-3-30-39.
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INTRODUCTION: The relevance of this issue is due to the fact that nowadays there is no common understanding of the influence degree of high partial oxygen pressures on a body functions’ state, depending on individual resistance.OBJECTIVE: Research the state of the functions of the central nervous, cardiovascular and respiratory systems among people with different resistance to the toxic oxygen effect in the descending and the nearest post-descending period.MATERIALS AND METHODS: There was an examination of 11 divers aged 23 to 43 (the average age is 35.5±6.5 years) in conditions of a simulated descent in a pressure chamber to the depth of 15 m (0.25 MPa) while breathing oxygen, and also during 3 days after its termination. Statistic: Software SPSS, v. 20.0 (IBM) was applied for statistical processing of the results.RESULTS: Baseline heart rate (HR) in the low toxic oxygen resistant group (group I) is 10% (р<0.05) higher than the subjects, recognized as resistant (group II). To 60 minutes oxygen breathing (pO2=0.25 MPa) there is a decrease in heart rate (HR) by 12.5% in group I and 11% in group II, comparing the baseline (р><0.05). An increase of diastolic pressure level in group II is 10.5% to 15 min descent and 18% to 45 min, comparing the baseline (р><0.05). In group I the pulse pressure level reduced by 18%, comparing the baseline (р><0.05). Gencha test results after descent rose by 55% in group I and by 62.5% in group II, comparing the baseline (р�0.05), and indicators higher than initial remained for 3 days more. In group I there was reduction of information processing speed by a visual analyzer of 16% (from 0.788 to 0.661 b/sec) and increase in escape latency of a simple visual-motor reaction by 11.7%, comparing the baseline (р><0.05). DISCUSSION: Divers with different resistance to the toxic oxygen effect experience multidirectional reaction of the central nervous, cardiovascular and respiratory systems. Individuals, resistant to the toxic oxygen effect, are characterized by more active inclusion of counteraction mechanisms to hyperoxia and significant reduction in the level of adaptation reserves and the efficiency of the cardiovascular system. People with low resistance experience a decrease in the functionality level of the central nervous system. CONCLUSION: The results obtained have a basis for admitting the application of the method of determining individual body resistance to the toxic oxygen effect and tests with increasing dosed physical activity in order to estimate adaptation reserves and efficiency. >< 0.05) higher than the subjects, recognized as resistant (group II). To 60 minutes oxygen breathing (pO2=0.25 MPa) there is a decrease in heart rate (HR) by 12.5% in group I and 11% in group II, comparing the baseline (р< 0.05). An increase of diastolic pressure level in group II is 10.5% to 15 min descent and 18% to 45 min, comparing the baseline (р< 0.05). In group I the pulse pressure level reduced by 18%, comparing the baseline (р< 0.05). Gencha test results after descent rose by 55% in group I and by 62.5% in group II, comparing the baseline (р 0.05), and indicators higher than initial remained for 3 days more. In group I there was reduction of information processing speed by a visual analyzer of 16% (from 0.788 to 0.661 b/sec) and increase in escape latency of a simple visual-motor reaction by 11.7%, comparing the baseline (р< 0.05).DISCUSSION: Divers with different resistance to the toxic oxygen effect experience multidirectional reaction of the central nervous, cardiovascular and respiratory systems. Individuals, resistant to the toxic oxygen effect, are characterized by more active inclusion of counteraction mechanisms to hyperoxia and significant reduction in the level of adaptation reserves and the efficiency of the cardiovascular system. People with low resistance experience a decrease in the functionality level of the central nervous system.CONCLUSION: The results obtained have a basis for admitting the application of the method of determining individual body resistance to the toxic oxygen effect and tests with increasing dosed physical activity in order to estimate adaptation reserves and efficiency.
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Mitton, Jeffry B., Cynthia Carey, and Thomas D. Kocher. "The Relation of Enzyme Heterozygosity to Standard and Active Oxygen Consumption and Body Size of Tiger Salamanders, Ambystoma tigrinum." Physiological Zoology 59, no. 5 (September 1986): 574–82. http://dx.doi.org/10.1086/physzool.59.5.30156122.
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Bao, Hui-Fang, John Z. Song, Billie J. Duke, He-Ping Ma, Donald D. Denson, and Douglas C. Eaton. "Ethanol stimulates epithelial sodium channels by elevating reactive oxygen species." American Journal of Physiology-Cell Physiology 303, no. 11 (December 1, 2012): C1129—C1138. http://dx.doi.org/10.1152/ajpcell.00139.2012.
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Alcohol affects total body sodium balance, but the molecular mechanism of its effect remains unclear. We used single-channel methods to examine how ethanol affects epithelial sodium channels (ENaC) in A6 distal nephron cells. The data showed that ethanol significantly increased both ENaC open probability ( Po) and the number of active ENaC in patches ( N). 1-Propanol and 1-butanol also increased ENaC activity, but iso-alcohols did not. The effects of ethanol were mimicked by acetaldehyde, the first metabolic product of ethanol, but not by acetone, the metabolic product of 2-propanol. Besides increasing open probability and apparent density of active channels, confocal microscopy and surface biotinylation showed that ethanol significantly increased α-ENaC protein in the apical membrane. The effects of ethanol on ENaC Po and N were abolished by a superoxide scavenger, 4-hydroxy-2,2,6,6-tetramethylpiperidinyloxy (TEMPOL) and blocked by the phosphatidylinositol 3-kinase inhibitor LY294002. Consistent with an effect of ethanol-induced reactive oxygen species (ROS) on ENaC, primary alcohols and acetaldehyde elevated intracellular ROS, but secondary alcohols did not. Taken together with our previous finding that ROS stimulate ENaC, the current results suggest that ethanol stimulates ENaC by elevating intracellular ROS probably via its metabolic product acetaldehyde.
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Abrantes, Catarina, Susana Martins, Ana Pereira, Fernando Policarpo, Isabel Machado, and Nelson Sousa. "Physiological Exercise and Post‐Exercise Effects of Inverse Sequences of Combined Bench‐Step Aerobics and Resistance Exercise." Journal of Human Kinetics 77, no. 1 (January 30, 2021): 61–70. http://dx.doi.org/10.2478/hukin-2021-0011.
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Abstract The purpose of this study was to compare the effects of using inverse sequences of combined bench-step aerobics and resistance exercise on cardiorespiratory, hemodynamic and perceptual variables during exercise and one-hour post-exercise. The tested sequences were bench-step aerobics immediately before and immediately after resistance exercise. Thirteen apparently healthy and physically active women (age = 21.9 ± 6.1 years, body height = 160 ± 0.1 cm, body mass = 58.8 ± 7.5 kg, estimated fat mass = 17.2 ± 2.0% and estimated maximal oxygen uptake = 37.5 ± 2.6 mL∙kg-1∙min-1) performed a 20-minute bench-step aerobics routine, immediately before (STEP_RES) and after (RES_STEP) resistance exercise. Oxygen uptake and heart rate were continuously measured, systolic and diastolic blood pressure, body temperature and perceived exertion were measured at rest, immediately after each type of exercise and at 15, 30, 45 and 60 min after exercise. When resistance exercise was performed first (RES_STEP), oxygen uptake was higher (23.2 ± 3.9 vs. 20.5 ± 4.8 mL∙kg-1∙min-1), but the heart rate (164.5 ± 9.1 vs. 173.9 ± 11.7 bpm) and body temperature (36.5 ± 0.4 vs. 37.6 ± 0.6 ºC) were lower. In both sequences, the type of exercise performed first was pointed out with a lower perceived exertion or lower perceived intensity. Exercise and 60-min post-exercise blood pressure had a similar response in both sequences, and systolic blood pressure along with diastolic blood pressure were lower than pre-exercise from 30 min until 60 min post-exercise. The results suggest that the sequence affected oxygen uptake and perceived exertion during exercise and that this total workload, despite the sequence, promoted a post-exercise blood pressure decrease in normotensive participants.
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Drafi, Frantisek, Katarina Bauerova, Viera Kuncirova, Silvester Ponist, Danica Mihalova, Tatiana Fedorova, Juraj Harmatha, and Radomir Nosal. "Pharmacological influence on processes of adjuvant arthritis: effect of the combination of an antioxidant active substance with methotrexate." Interdisciplinary Toxicology 5, no. 2 (November 9, 2012): 84–91. http://dx.doi.org/10.2478/v10102-012-0015-4.
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Abstract Oxygen metabolism has an important role in the pathogenesis of rheumatoid arthritis. A certain correlation was observed between oxidative stress, arthritis and the immune system. Reactive oxygen species produced in the course of cellular oxidative phosphorylation and by activated phagocytic cells during oxidative burst, exceed the physiological buffering capacity and result in oxidative stress. The excessive production of ROS can damage protein, lipids, nucleic acids, and matrix components. Patients with rheumatoid arthritis have an altered antioxidant defense capacity barrier. In the present study the effect of substances with antioxidative properties, i.e. pinosylvin and carnosine, was determined in monotherapy for the treatment of adjuvant arthritis (AA). Moreover carnosine was evaluated in combination therapy with methotrexate. Rats with AA were administered first pinosylvin (30 mg/kg body mass daily per os), second carnosine (150 mg/kg body mass daily per os) in monotherapy for a period of 28 days. Further, rats with AA were administered methotrexate (0.3 mg/kg body mass 2-times weekly per os), and a combination of methotrexate+carnosine, with the carnosine dose being the same as in the previous experiment. Parameters, i.e. changes in hind paw volume and arthritic score were determined in rats as indicators of destructive arthritis-associated clinical changes. Plasmatic levels of TBARS and lag time of Fe2+- induced lipid peroxidation (tau-FeLP) in plasma and brain were specified as markers of oxidation. Plasmatic level of CRP and activity of γ-glutamyltransferase (GGT) in spleen and joint were used as inflammation markers. In comparison to pinosylvin, administration of carnosine monotherapy led to a significant decrease in the majority of the parameters studied. In the combination treatment with methotrexate+carnosine most parameters monitored were improved more remarkably than by methotrexate alone. Carnosine can increase the disease-modifying effect of methotrexate treatment in rat AA.
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Noren, Shawn R. "Postnatal development of diving physiology: implications of anthropogenic disturbance for immature marine mammals." Journal of Experimental Biology 223, no. 17 (September 1, 2020): jeb227736. http://dx.doi.org/10.1242/jeb.227736.
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ABSTRACTMarine mammals endure extended breath-holds while performing active behaviors, which has fascinated scientists for over a century. It is now known that these animals have large onboard oxygen stores and utilize oxygen-conserving mechanisms to prolong aerobically supported dives to great depths, while typically avoiding (or tolerating) hypoxia, hypercarbia, acidosis and decompression sickness (DCS). Over the last few decades, research has revealed that diving physiology is underdeveloped at birth. Here, I review the postnatal development of the body's oxygen stores, cardiorespiratory system and other attributes of diving physiology for pinnipeds and cetaceans to assess how physiological immaturity makes young marine mammals vulnerable to disturbance. Generally, the duration required for body oxygen stores to mature varies across species in accordance with the maternal dependency period, which can be over 2 years long in some species. However, some Arctic and deep-diving species achieve mature oxygen stores comparatively early in life (prior to weaning). Accelerated development in these species supports survival during prolonged hypoxic periods when calves accompany their mothers under sea ice and to the bathypelagic zone, respectively. Studies on oxygen utilization patterns and heart rates while diving are limited, but the data indicate that immature marine mammals have a limited capacity to regulate heart rate (and hence oxygen utilization) during breath-hold. Underdeveloped diving physiology, in combination with small body size, limits diving and swimming performance. This makes immature marine mammals particularly vulnerable to mortality during periods of food limitation, habitat alterations associated with global climate change, fishery interactions and other anthropogenic disturbances, such as exposure to sonar.
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Arngrïmsson, Sigurbjörn Á., Darby S. Petitt, Matthew G. Stueck, Dennis K. Jorgensen, and Kirk J. Cureton. "Cooling vest worn during active warm-up improves 5-km run performance in the heat." Journal of Applied Physiology 96, no. 5 (May 2004): 1867–74. http://dx.doi.org/10.1152/japplphysiol.00979.2003.
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We investigated whether a cooling vest worn during an active warm-up enhances 5-km run time in the heat. Seventeen competitive runners (9 men, maximal oxygen uptake = 66.7 ± 5.9 ml·kg-1·min-1; 8 women, maximal oxygen uptake = 58.0 ± 3.2 ml·kg-1·min-1) completed two simulated 5-km runs on a treadmill after a 38-min active warm-up during which they wore either a T-shirt (C) or a vest filled with ice (V) in a hot, humid environment (32°C, 50% relative humidity). Wearing the cooling vest during warm-up significantly ( P < 0.05) blunted increases in body temperature, heart rate (HR), and perception of thermal discomfort during warm-up compared with control. At the start of the 5-km run, esophageal, rectal, mean skin, and mean body temperatures averaged 0.3, 0.2, 1.8, and 0.4°C lower; HR averaged 11 beats/min lower; and perception of thermal discomfort (5-point scale) averaged 0.6 point lower in V than C. Most of these differences were eliminated during the first 3.2 km of the run, and these variables were not different at the end. The 5-km run time was significantly lower ( P < 0.05) by 13 s in V than C, with a faster pace most evident during the last two-thirds of the run. We conclude that a cooling vest worn during active warm-up by track athletes enhances 5-km run performance in the heat. Reduced thermal and cardiovascular strain and perception of thermal discomfort in the early portion of the run appear to permit a faster pace later in the run.
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Stojmenovic, Tamara, Djordje Curcic, Milica Vukasinovic-Vesic, Marija Andjelkovic, Nenad Dikic, Marija Kostic-Vucicevic, Ivana Baralic, Vladimir Jakovljevic, and Vladimir Zivkovic. "Changes in maximal oxygen uptake during growth and development in girls who actively participate in basketball and in non-athletes girls: A longitudinal study." Vojnosanitetski pregled 75, no. 5 (2018): 481–86. http://dx.doi.org/10.2298/vsp150901326s.
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Background/Aim. It is well known that continuous engagement in physical activity is important for normal growth and development of children. Maximal oxygen uptake (VO2max), as a measure of functional state of the organism, is largely affected by level of physical activity, but it remains unclear to what extent it can be improved during childhood. The aim of the study was to evaluate dynamics of changes in aerobic capacity, anthropometric and body composition characteristics in active and non-active girls over a period of 3 years. Methods. A total of 48 young girls were included in the study. Girls were divided into 2 groups: training group consisted of 25 girls who played basketball (age 13.84 ? 0.94) and non-training group of 23 girls who were not involved in any organized sports (age 13.83 ? 0.98). Anthropometric and body composition characteristics were measured in order to monitor somatic growth during the study. VO2maxvalues were obtained by performing cardiopulmonary exercise testing on a treadmill. All parameters were measured every 6 months during 3-years period. Results. ANOVA analysis showed a significant time and group interaction effect on VO2max (p < 0.001), body mass index (BMI) (p < 0.001) and fat percentage (FAT%) (p < 0.01). Also, there was an obvious increase in VO2max within both groups due to growth and development itself (p < 0.001). Conclusion. The main finding of the study was an increase in VO2max due to growth and development. The girls who actively participated in basketball had higher level of aerobic capacity compared to non-active girls. Furthermore, continuous basketball training led to maintaining normal body composition in terms of FAT% and BMI, which altogether may imply that organized physical activity has a positive influence on evaluated characteristics.
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Chai, P., R. Harrykissoon, and R. Dudley. "Hummingbird hovering performance in hyperoxic heliox: effects of body mass and sex." Journal of Experimental Biology 199, no. 12 (December 1, 1996): 2745–55. http://dx.doi.org/10.1242/jeb.199.12.2745.
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Owing to their small size and hovering locomotion, hummingbirds are the most aerobically active vertebrate endotherms. Can hyperoxia enhance the flight performance of this highly oxygen-dependent group? Hovering performance of ruby-throated hummingbirds (Archilochus colubris) was manipulated non-invasively using hyperoxic but hypodense gas mixtures of sea-level air combined with heliox containing 35% O2. This manipulation sheds light on the interplay among metabolic power input, mechanical power output and aerodynamic force production in limiting flight performance. No significant differences in flight mechanics and oxygen consumption were identified between hyperoxic and normoxic conditions. Thus, at least in the present experimental context, hyperoxia did not change the major metabolic and mechanical parameters; O2 diffusive capacities of the respiratory system were probably not limiting to a significant extent. Compared with hummingbirds in our previous studies, the present experimental birds were heavier, had resultant shorter hover-feeding durations and experienced aerodynamic failure at higher air densities. Because hummingbirds have relatively stable wingbeat frequencies, modulation of power output was attained primarily through variation in stroke amplitude up to near 180 degrees. This result indicates that maximum hovering performance was constrained geometrically and that heavier birds with greater fat loads had less margin for enhancement of power production. Sexual dimorphism in flight adaptation also played a role, with males showing more limited hovering capacities, presumably as a trade-off for increased maneuverability.
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Schetinin, S. "Mechanisms and practical use of the bactericidal effects of ozone and ozonated oils." Terapevt (General Physician), no. 6 (June 1, 2020): 45–52. http://dx.doi.org/10.33920/med-12-2006-06.
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The analysis of the clinical and immunological effectiveness of ozone therapy is carried out. The mechanism of the bactericidal action of ozone in the treatment of infectious and inflammatory diseases of a bacterial and viral nature is analyzed. Ozonation of oils leads to the formation of a complex and heterogeneous cascade of components. Ozonides provide the body with some prolonged supply of active oxygen to maintain aerobic metabolism and the required level of energy substrates.
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Kramarova, L. I., S. G. Kolaeva, G. E. Bronnikov, A. D. Ignatiev, and I. V. Krasts. "Hypometabolic and hypothermic factors from small intestine of hibernating ground squirrels (Citellus undulatus)." Canadian Journal of Physiology and Pharmacology 71, no. 3-4 (March 1, 1993): 293–96. http://dx.doi.org/10.1139/y93-045.
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Low molecular mass components of the acetic acid extract from the small intestine of hibernating ground squirrels (Citellus undulatus) produced a decrease in oxygen consumption and body temperature of white mice and a dose-dependent delay in embryonic development of sea urchin (Strongylocentrotus intermedius). Equivalent doses of low molecular mass components obtained by the same method from active (summer) animals did not have such an effect.Key words: hibernation, hypometabolic factors, hypothermic factors, sea urchin.
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BEVAN, R. M., and P. J. BUTLER. "THE EFFECTS OF TEMPERATURE ON THE OXYGEN CONSUMPTION, HEART RATE AND DEEP BODY TEMPERATURE DURING DIVING IN THE TUFTED DUCK AYTHYA FULIGULA." Journal of Experimental Biology 163, no. 1 (February 1, 1992): 139–51. http://dx.doi.org/10.1242/jeb.163.1.139.
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Six tufted ducks were trained to dive for food at summer temperatures (air, 26°C, water, 23°C) and at winter temperatures (air, 5.8°C, water 7.4°C). The mean resting oxygen consumption (Voo2) a t winter temperatures (rwin) was 90% higher than that at summer temperatures (Tsum), but deep body temperatures (Tb) were not significantly different. Diving behaviour and mean oxygen consumption for dives of mean duration were similar at Twin and at Tsum, although the mean oxygen consumption for surface intervals of mean duration was 50% greater at Twin and Tb was significantly lower (1°C) at the end of a series of dives in winter than it was in summer. There appears to be an energy saving of 67 J per dive during winter conditions and this may, at least partially, be the result of the metabolic heat produced by the active muscles being used to maintain body temperature. While at rest under winter conditions, this would be achieved by shivering thermogenesis. Thus, the energetic costs of foraging in tufted ducks in winter are not as great as might be expected from the almost doubling of metabolic rate in resting birds.
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Jurov, Iva, Janez Toplišek, and Marta Cvijić. "Prediction of Maximal Oxygen Consumption in Cycle Ergometry in Competitive Cyclists." Life 13, no. 1 (January 5, 2023): 160. http://dx.doi.org/10.3390/life13010160.
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Models for predicting maximal oxygen consumption (VO2max) in average adults might not be suitable for athletes, especially for competitive cyclists who can have significantly higher VO2max than normally active people. The aim of this study was to develop a clinically applicable equation for predicting VO2max during cycle ergometry in competitive cyclists and to compare its accuracy to the traditional American College of Sports Medicine (ACSM) equation. Maximal cycle ergometry tests were performed in 496 male and 84 female competitive cyclists. Six predictors were initially used to model the prediction equation (power output, body weight, body height, fat mass, fat-free mass and age). Power output and body weight were the most important parameters in the model predicting VO2max. Three new equations were derived: for male (VO2max = 0.10 × PO − 0.60 × BW + 64.21), female cyclists (0.13 × PO − 0.83 × BW + 64.02) and the non-gender-specific formula (0.12 × PO − 0.65 × BW + 59.78). The ACSM underestimated VO2max in men by 7.32 mL/min/kg (11.54%), in women by 8.24 mL/min/kg (15.04%) and in all participants by 7.45 mL/min/kg (11.99%), compared to the new equation that underestimated VO2max in men by 0.12 mL/min/kg (0.19%) and in all participants by 0.65 mL/min/kg (1.04%). In female cyclists, the new equation had no relative bias. We recommend that medicine and sports practitioners adapt our proposed equations when working with competitive cyclists. Our findings demonstrate the need to evaluate prediction models for other athletes with a special focus on disciplines that demand high aerobic capacity.
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Tantowi, Ferdy, and David Limanan. "Antioxidant Test, Total Alkaloid Content, Antimitosis Test and HPTLC Test of Chamomile Flower Extract (Matricaria Chamomilla L.)." Devotion Journal of Community Service 4, no. 1 (January 12, 2023): 78–87. http://dx.doi.org/10.36418/dev.v4i1.351.
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Oxygen is one of the supports of multicellular life and is necessary for aerobic metabolism. However, the use of oxygen can produce by-products, one of which is reactive oxygen species (ROS) which can also increase due to external factors such as exposure to ionizing rays, and vehicle smoke. When reactive oxygen species levels are high, the body can experience a condition called oxidative stress, which is a condition that can cause tissue damage. To overcome this, antioxidants are needed, namely compounds that can donate electrons to free radicals to neutralize their effects. Antioxidants are divided into endogenous antioxidants and exogenous antioxidants. Endogenous antioxidants are antioxidants found in the body. Exogenous antioxidants are antioxidants that come from outside the body. Because there is an increase in ROS levels due to external influences, an increase in exogenous antioxidants is needed, one of which is chamomile flowers. This study evaluated qualitative phytochemical levels using the Harnborne method, total antioxidant capacity using the Blois method, total quantitative levels of alkaloids using the Trivedi et al method, BSLT toxicity using the Meyer method, and fingerprint analysis using HPTLC. The obtained chamomile flowers are dried and extracted by maceration using methanol solvent. The test results on chamomile flowers revealed phytochemical content in the form of alkaloids, betasianin, cardioglycosides, coumarins, flavonoids, phenols, quinones, saponins, steroids, tepenoids and tannins. Antioxidant ability 209.27 g/ml; Total alkaloid content of 12.62 g/ml; toxicity 174.39 g/mL; As well as fingerprint analysis chamomile flowers have active ingredients. Therefore, chamomile flowers can serve as a moderate antioxidant with antimitotic activity.
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Murtuza, F., AJ Farrier, M. Venkatesan, R. Smith, A. Khan, CE Uzoigwe, and G. Chami. "Is there an association between body temperature and serum lactate levels in hip fracture patients?" Annals of The Royal College of Surgeons of England 97, no. 7 (October 1, 2015): 513–18. http://dx.doi.org/10.1308/rcsann.2015.0012.
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Introduction Hyperlactataemia is associated with adverse outcomes in trauma cases. It is thought to be the result of anaerobic respiration during hypoperfusion. This produces much less energy than complete aerobic glycolysis. Low body temperature in the injured patient carries an equally poor prognosis. Significant amounts of energy are expended in maintaining euthermia. Consequently, there may be a link between lactate levels and dysthermia. Hyperlactataemia may be indicative of inefficient energy production and therefore insufficient energy to maintain euthermia. Alternatively, significant amounts of available oxygen may be sequestered in thermoregulation, resulting in anaerobic respiration and lactate production. Our study investigated whether there is an association between lactate levels and admission body temperature in hip fracture patients. Furthermore, it looked at whether there is a difference in the mean lactate levels between hip fracture patients with low (<36.5°C), normal (36.5–37.5°C) and high (>37.5°C) body temperature on admission, and for patients who have low body temperature, whether there is a progressive rise in serum lactate levels as body temperature falls. Methods The admission temperature and serum lactate of 1,162 patients presenting with hip fracture were recorded. Patients were divided into the euthermic (body temperature 36.5–37.5°C), the pyrexial (>37.5°C) and those with low body temperature (<36.5°C). Admission lactate and body temperature were compared. Results There was a significant difference in age between the three body temperature groups (p=0.007). The pyrexial cohort was younger than the low body temperature group (mean: 78 vs 82 years). Those with low body temperature had a higher mean lactate level than the euthermic (2.2mmol/l vs 2.0mmol/l, p=0.03). However, there was no progressive rise in serum lactate level as admission temperature fell. Conclusions The findings suggest that in hip fracture patients, the body attempts initially to maintain euthermia, incurring an oxygen debt. This would explain the difference in lactate level between the low body temperature and euthermic cohorts. The fact that there is no correlation with the degree of temperature depression and lactate levels indicates that the body does not fuel thermohomeostasis indefinitely with oxygen. Instead, in part, it abandons thermoregulatory mechanisms. Consequently, in this population, active rewarming may be indicated rather than depending on patients’ own thermogenic ability.
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Butler, P. J. "The exercise response and the "classical" diving response during natural submersion in birds and mammals." Canadian Journal of Zoology 66, no. 1 (January 1, 1988): 29–39. http://dx.doi.org/10.1139/z88-004.
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When swimming at the surface with ready access to the air, aquatic birds and mammals appear to show the typical exercise response. There are increases in oxygen uptake, heart rate, and pulmonary ventilation. These are presumably accompanied by rises in cardiac output and perfusion to the active muscles, together with a reduction in overall peripheral vascular resistance. When restrained animals are submerged under water involuntarily, total oxygen consumption is reduced below the resting level as a result of a large reduction in perfusion of most parts of the body (including skeletal muscles) except the brain and heart. The underperfused parts metabolise anaerobically, producing lactic acid, while only the brain and heart consume oxygen. The large increase in peripheral vascular resistance is compensated by a proportionally similar reduction in cardiac output which results almost entirely from a reduction in heart rate below the resting level. This is the classical diving bradycardia. Evidence is presented from a number of aquatic birds and mammals that suggests that during the vast majority of natural dives metabolism is largely if not completely aerobic with the active skeletal muscles as well as the brain and heart receiving an adequate supply of oxygen. There may, however, be a reduced blood supply to other parts of the body including to the inactive skeletal muscles. Thus during most natural dives stored oxygen is used at an elevated rate, compared with resting, and is quickly replaced upon surfacing. It is possible for the animals to perform a number of such dives in fairly quick succession. In tufted ducks, at least, there seems to be a balance between the cardiovascular response to exercise and that to involuntary submersion with the bias towards the former. This balance can be shifted in the direction of the response to involuntary submersion when the birds swim long horizontal distances for their food (e.g., under ice in winter) or if they are briefly unable to surface (e.g., if rising vertically beneath ice).