419 results on '"HORVATH SM"'
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2. Design and Measurement Considerations for Exercise Protocols in Human Air Pollution Inhalation Studies
- Author
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Horvath, SM, primary
- Published
- 1985
- Full Text
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3. NMR analysis of lipoprotein particle size does not increase sensitivity to the effect of soy protein on CVD risk when compared with the traditional lipid profile.
- Author
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Santo AS, Cunningham AM, Alhassan S, Browne RW, Burton H, Leddy JJ, Grandjean PW, Horvath SM, and Horvath PJ
- Published
- 2008
- Full Text
- View/download PDF
4. Responses of the hepatic circulation to various pharmacologic agents: A Review
- Author
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Horvath Sm and Bender Ad
- Subjects
Vasopressin ,medicine.medical_specialty ,Physiology ,Vasodilator Agents ,Hemodynamics ,Catecholamines ,Internal medicine ,Renin–angiotensin system ,medicine ,Sympatholytics ,Sympathomimetics ,Phenylephrine ,Antihypertensive Agents ,Guanethidine ,Anesthetics ,Pharmacology ,business.industry ,Gastroenterology ,General Medicine ,Endocrinology ,Trimethaphan ,Serotonin ,business ,Liver Circulation ,medicine.drug - Abstract
The response of the hepatic circulation to various drugs is related to a number of diffierent hemodynamic factors: those which are the direct results of the drug acting on the vessels of the liver, and indirect influences as well resulting from hemodynamic changes induced in other components of the peripheral circuit. The effect on hepatic flow per se is the algebraic sum of these factors, the predominance being related directly to the action of the drug. With some (vasopressin, trimethaphan), a parallel effect on each regional circuit is produced, in which case, no selective or preferential redistribution of flow is evident. In other instances, however, the hepatic circulation may be favored (norepinephrine, phenylephrine, guanethidine) or deficient (angiotensin, serotonin) with respect to changes in total peripheral flow, depending on the extrahepatic influences of the drug. Indeed, changes in hepatic flow may reflect strictly an extrahepatic effect (isoproterenol). It may be concluded that the response of the hepatic circulation to drugs is the result of a combination of factors, and in the intact animal, rarely reflects the response of the hepatic vasculature alone.
- Published
- 1965
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5. Blood Glucose as Influenced by Either One or Two Meals
- Author
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Thornton Rh and Horvath Sm
- Subjects
Nutrition and Dietetics ,Milk products ,Blood chemistry ,Chemistry ,Blood sugar ,Food science ,Food Science - Published
- 1968
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6. The response of the splanchnic bed of chronically splenectomized dogs to epinephrine and norepinephrine infusion
- Author
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Bender Ad and Horvath Sm
- Subjects
Epinephrine ,Physiology ,business.industry ,medicine.medical_treatment ,Splenectomy ,Blood flow ,Biochemistry ,Norepinephrine (medication) ,Norepinephrine ,Blood pressure ,Dogs ,Anesthesia ,Blood circulation ,Blood Circulation ,Medicine ,Animals ,Splenic bed ,business ,Splanchnic ,medicine.drug - Abstract
The infusion of 1-epinephrine for 10 minutes induced an increase in splanchnic blood flow with no change in mean arterial blood pressure. During the first half of the infusion the increase in blood flow of the splenectomized group was significantly below the increase noted in normal intact dogs (previous publication). It was suggested that this was due to a lack of splenic contribution to portal flow under the influence of epinephrine. Following the infusion the splenectomized dogs exhibited a marked reduction in blood flow while in intact dogs the flow returned to control values. It was concluded that the increase in resistance which was responsible for the lower flow rate was due to the removal of the splenic bed since the splenic mesenteric systems comprise a parallel circuit. No change in flow was observed during norepinephrine infusion. However, a similar depression in flow to that seen in animals given epinephrine was noted after the infusion was stopped.
- Published
- 1962
7. Heating of human tissues by micro wave radiation
- Author
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Miller Rn, Hutt Bk, and Horvath Sm
- Subjects
Heating ,Tissues ,business.industry ,Tissue heating ,Medicine ,Humans ,General Medicine ,Radiation ,business ,Biomedical engineering - Published
- 1948
8. Effects of training on weight, food intake, and body composition in aging rats
- Author
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Mazzeo, RS, primary and Horvath, SM, additional
- Published
- 1986
- Full Text
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9. Operant conditioning of heart rate in curarized rats: hemodynamic changes
- Author
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Gliner, JA, primary, Horvath, SM, additional, and Wolfe, RR, additional
- Published
- 1975
- Full Text
- View/download PDF
10. Cardiac output in the cold-stressed swimming rat
- Author
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Dawson, CA, primary, Nadel, ER, additional, and Horvath, SM, additional
- Published
- 1968
- Full Text
- View/download PDF
11. Postprandial lipemia detects the effect of soy protein on cardiovascular disease risk compared with the fasting lipid profile.
- Author
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Santo AS, Santo AM, Browne RW, Burton H, Leddy JJ, Horvath SM, and Horvath PJ
- Subjects
- Adolescent, Adult, Cardiovascular Diseases prevention & control, Cholesterol, HDL blood, Cholesterol, LDL blood, Double-Blind Method, Fasting, Humans, Isoflavones pharmacology, Lipid Metabolism, Male, Risk Factors, Triglycerides blood, Cardiovascular Diseases epidemiology, Hyperlipidemias blood, Lipids blood, Postprandial Period physiology, Soybean Proteins pharmacology
- Abstract
Studies examining the effect of soy protein on cardiovascular disease (CVD) risk factors have not taken advantage of the postprandial state as an adjunct to the fasting lipid profile. The American Heart Association has acknowledged the efficacy of soy protein in reducing CVD risk factors to be limited. We hypothesized that the postprandial state would be more sensitive to any favorable changes associated with consuming soy protein compared with the fasting lipid profile. Furthermore, the presence of isoflavones in soy would enhance this effect. Thirty sedentary males aged 18-30 years were randomly assigned to milk protein (Milk), isoflavone-poor soy (Soy-), or isoflavone-rich soy (Soy+). Usual diets were supplemented with 25 g/day of protein for 28 days. Serum samples were collected before and after supplementation in a fasted state and postprandially at 30, 60, 120, 240, and 360 min after a high-fat, 1,000 kcal shake. Triacylglycerol (TAG), total cholesterol, non-esterified fatty acids, apolipoproteins B-100 and A-I and glucose concentrations were quantified. Fasting concentrations were not different after any protein supplementation. Postprandial TAG and TAG AUC increased after Soy-consumption supporting the postprandial state as a more sensitive indicator of soy ingestion effects on CVD risk factors compared with the fasting lipid profile. Furthermore, the absence of isoflavones in soy protein may have deleterious consequences on purported cardio-protective effects.
- Published
- 2010
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12. Individual differences in physiological responses and type A behavior pattern.
- Author
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Oishi K, Kamimura M, Nigorikawa T, Nakamiya T, Williams RE, and Horvath SM
- Subjects
- Adolescent, Adult, Female, Humans, Japan, Male, Psychophysiology, Type A Personality
- Abstract
The relationships between individual differences in psychophysiological responses and tendency of Type A behavior pattern (TABP) were investigated during mental arithmetic (MA) at a steady rhythm, challenging calculation (Uchida-Kraepelin serial addition test: UK test), music listening, and exposure to an 80 dB SPL of white noise. Each mental task was sustained for 5 minutes. Sixteen healthy Japanese adults, (10 males and 6 females) with an age from 18 to 36 years old volunteered for this study. The KG's Daily Life Questionnaire (KG Questionnaire) was used to investigate the tendency toward TABP, which included three sub-factors: aggression-hostility, hard-driving and time urgency, and speed-power items. Recorded physiological variables were respiratory rate (RR), skin resistance response (SRR), eyeblinks, and heart rate (HR) calculated using frequency analysis to render high frequency power (HF) and the ratio of low/high frequencies (L/H ratio). During the MA and UK tests, significant increases in HR, L/H ratio, RR occurred, while significant decreases in HF were observed. Eyeblinks significantly increased during the MA test and significantly decreased during the UK test. During music and white noise, no significant changes occurred except for SRR, which decreased significantly. The coefficient of variances in each response was over 20% for almost all variables, indicating that individual differences in the magnitude of each response were large, even if the direction (increase or decrease) of the change was the same in almost all subjects. The highest correlation coefficients (r) between the mean values of relative magnitude for each variable and TABP scores during the MA and UK tests were obtained for the L/H ratio (MA: r = 0.591, UK test: r = 0.577) and the RR (MA: r = -0.576, UK test: r = -0.511). These values were statistically significant (p < 0.05). Similar results were obtained for TABP sub-factors. Though other investigations have reported relationships between HF and TABP, we found no significant relationship. It was suggested that sympathetic nerve activity became greater for TABP individuals than for Type B individuals under stress conditions.
- Published
- 1999
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13. Alpha-2 macroglobulin is genetically associated with Alzheimer disease.
- Author
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Blacker D, Wilcox MA, Laird NM, Rodes L, Horvath SM, Go RC, Perry R, Watson B Jr, Bassett SS, McInnis MG, Albert MS, Hyman BT, and Tanzi RE
- Subjects
- Age of Onset, Apolipoprotein E4, Apolipoproteins E genetics, Chromosomes, Human, Pair 12 genetics, Family, Gene Frequency, Genetic Testing, Genotype, Humans, Lod Score, Logistic Models, Risk Factors, Alzheimer Disease genetics, Genetic Linkage, alpha-Macroglobulins genetics
- Abstract
Alpha-2-macroglobulin (alpha-2M; encoded by the gene A2M) is a serum pan-protease inhibitor that has been implicated in Alzheimer disease (AD) based on its ability to mediate the clearance and degradation of A beta, the major component of beta-amyloid deposits. Analysis of a deletion in the A2M gene at the 5' splice site of 'exon II' of the bait region (exon 18) revealed that inheritance of the deletion (A2M-2) confers increased risk for AD (Mantel-Haenzel odds ratio=3.56, P=0.001). The sibship disequilibrium test (SDT) also revealed a significant association between A2M and AD (P=0.00009). These values were comparable to those obtained for the APOE-epsilon4 allele in the same sample, but in contrast to APOE-epsilon4, A2M-2 did not affect age of onset. The observed association of A2M with AD did not appear to account for the previously published linkage of AD to chromosome 12, which we were unable to confirm in this sample. A2M, LRP1 (encoding the alpha-2M receptor) and the genes for two other LRP ligands, APOE and APP (encoding the amyloid beta-protein precursor), have now all been genetically linked to AD, suggesting that these proteins may participate in a common neuropathogenic pathway leading to AD.
- Published
- 1998
- Full Text
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14. Total body fat estimations by near-infrared interactance, A-mode ultrasound, and underwater weighing.
- Author
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Yasukawa M, Horvath SM, Oishi K, Kimura M, Williams R, and Maeshima T
- Subjects
- Adipose Tissue anatomy & histology, Adipose Tissue diagnostic imaging, Adipose Tissue physiology, Adolescent, Adult, Aged, Anthropometry, Female, Humans, Male, Middle Aged, Sex Characteristics, Body Composition physiology, Body Weight physiology, Immersion, Spectrophotometry, Infrared, Ultrasonography
- Abstract
We studied 94 (41 men and 53 women) healthy 18 to 65 years old Caucasians for body composition utilizing 3 methods: 1) Underwater weighing (UWW) for body density, 2) A-mode ultrasound subcutaneous fat determination, and 3) Near-infrared (NIR) interactance spectral data. We then utilized the Wherry-Doolittle test selection method to predict percent of total body fat (%fat) from either ultrasound or NIR data with anthropometric measurements, optimizing for the fewest number of data points which correlated highly with UWW results. It was found that %fat could be estimated with a correlation of > 0.9 when measured at 4 sites (different between men and women) by ultrasound, age (women) and height (men). We also found a correlation of > 0.8 using 2 sites by NIR, weight, age, and height. It has been suggested that the ultrasound method would produce better estimates of both local and total body fat.
- Published
- 1995
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15. Recovery from dynamic exercise.
- Author
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Williams RE and Horvath SM
- Subjects
- Adult, Analysis of Variance, Carbon Dioxide metabolism, Cardiac Output, Exercise Test, Heart Rate, Humans, Male, Respiration, Stroke Volume, Time Factors, Exercise, Hemodynamics, Oxygen Consumption, Physical Exertion
- Abstract
Minimal information is available on the basic interactions within the metabolic and cardiovascular systems during recovery from exercise. Nine men participated in three experiments: one control and two cost-equivalent (52 liters O2) exercise tests of 30 (EX30) and 45 (EX45) min. Exercise intensities were adjusted accordingly. During recovery, all parameters reestablished baseline levels within 10 min, except for heart rate (30 min). Correlations for each parameter for EX30 and EX45 were obtained by evaluating each subject's exercise cost and recovery "payback." A split, two-factor analysis of variance was run separately on the "fast" (minutes 1-7) and "slow" (minutes 10-60) phases of recovery to determine if the time course of recovery was related to exercise intensity. It was concluded that for a work cost of approximately 300 kcal, 1) the slow phase of recovery was unaffected by the exercise intensity, 2) the fast phase of cardiovascular recovery was unaffected by exercise intensity while minute ventilation and O2 and CO2 uptake were affected, and 3) cardiac output and the ventilatory equivalents for O2 and CO2 correlated well between work cost and recovery payback.
- Published
- 1995
- Full Text
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16. Population differences in cardiovascular reactivity to the cold pressor test.
- Author
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Duncan MT, Husain R, Chen HM, and Horvath SM
- Abstract
The interaction of race and climatic adaptation on patterns of cardiovascular reactivity among young adult males was examined. Malay and Chinese subjects living in a tropical climate in the Orient and Caucasians living in a sub-tropical climate in North America were investigated. The cold pressor test with hand immersion in cold water was used as the stressor. Systolic and diastolic blood pressures, cardiac frequency, cardiac output, and stroke volume were measured. The results provided limited evidence for absence of differences in cardiac reactivity among racial groups and for greater vascular reactivity in the Caucasians. Cold immersion also elicited differential responses which could be partially attributed to differences in acclimatizations status. © 1995 Wiley-Liss, Inc., (Copyright © 1995 Wiley-Liss, Inc., A Wiley Company.)
- Published
- 1995
- Full Text
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17. Aerobic power and body size affects the exercise-induced stress hormone responses to varying water temperatures.
- Author
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McMurray RG, Kocher PL, and Horvath SM
- Subjects
- Adolescent, Adult, Aerobiosis, Humans, Immersion, Male, Temperature, Body Constitution, Dopamine urine, Epinephrine urine, Exercise physiology, Hydrocortisone blood, Norepinephrine urine, Water
- Abstract
Eleven active male subjects were used to examine the effects of anthropometrics and aerobic power (VO2max) on the plasma cortisol (CO) and urine excretion of catecholamines (NE and E) and dopamine (D) during exercise in differing water temperatures. Each performed 30 min of cycle ergometer exercise at 60% VO2max while immersed to the neck in 20, 25, 30, and 35 degrees C water (Tw). The change in core temperature (delta Tre) during exercise was related to Tw (p < 0.007). Plasma CO (exercise - rest) increased during the 20 degrees C trials and decreased during the 30 and 35 degrees C trials (p = 0.011). Catecholamines were generally higher during the 20 and 35 degrees C trials than the 25 and 30 degrees C trials, with significance for only D and NE during the 35 degrees C vs. 25 degrees C trials (p < 0.05). Multiple regression analyses (MRA) with CO during the 20 degrees C trials revealed that VO2max and delta Tre were significant partial correlates (p < 0.05), while in 35 degrees C water body mass index and delta Tre were significant partial correlates (p < 0.05). MRAs with NE and E during the 20 degrees C trials indicated that body fat was the only consistent significant partial correlate. The MRA for NE and E during the 35 degrees C trials were not significant; however, the MRA for D was significant. These results indicate that in addition to the core temperature, anthropometrics, and aerobic power affect the exercise-induced stress hormone responses during exposures to cold and warm water.
- Published
- 1994
18. Maximal exercise response of paraplegic wheelchair road racers.
- Author
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Cooper RA, Horvath SM, Bedi JF, Drechsler-Parks DM, and Williams RE
- Subjects
- Adult, Blood Pressure physiology, Body Temperature physiology, Electrocardiography, Exercise Test, Humans, Male, Oxygen Consumption physiology, Respiratory Function Tests, Sweating physiology, Paraplegia physiopathology, Sports, Wheelchairs
- Abstract
The maximal metabolic responses of 11 paraplegic wheelchair road racers were evaluated with 2 wheelchair exercise protocols: increasing speed and increasing resistance. The maximal heart rates, minute ventilations and oxygen uptakes were similar for the 2 tests, indicating that either protocol is suitable for maximal wheelchair dynamometer exercise tests for groups. The resulting data were then compared to published data on maximal arm exercise by athletic and non athletic paraplegics and ambulatory males of the same age group. The combined mean values for both exercise tests of maximal oxygen consumption rate (VO2max = 37.4 ml/kg/min), minute ventilation (VE = 109.4 l/min), respiratory exchange quotient (RQmax = 1.18) and heart rate (187 beats/min) are in the mid range of reported data on wheelchair athletes. The mean RQ and heart rate values were similar to those achieved by ambulatory individuals performing maximal exercise tests. The mean VO2max of 37.4 ml/kg/min in our subjects is comparable to that achieved by sedentary ambulatory males of this age group. The data and the comparison to published data suggest several conclusions: in some parameters elite male paraplegic road racers have maximal values similar to those of ambulatory males, and in others they have maximal values substantially lower than might be expected; there is considerable variability among paraplegics in the metabolic responses to maximal exercise, most likely related to differences in cardiovascular fitness; and paraplegics can improve their cardiovascular fitness by training.
- Published
- 1992
- Full Text
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19. Immersion diuresis occurs independently of water temperatures in the range 25 degrees-35 degrees C.
- Author
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Knight DR and Horvath SM
- Subjects
- Drinking, Humans, Temperature, Water, Diuresis, Immersion physiopathology
- Published
- 1990
20. Heat, cold, noise, and vibration.
- Author
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Horvath SM and Bedi JF
- Subjects
- Environmental Exposure, Humans, Cold Temperature adverse effects, Hot Temperature adverse effects, Noise adverse effects, Vibration adverse effects
- Abstract
Exposure to a cold environment induces a number of physiological alterations, the most serious being hypothermia. This state can occur in all individuals, but the very young and the elderly are more susceptible. Environmental and industrially generated high ambient temperature can place further stress on aged individuals and workers, resulting in a complex symptom picture. Morbidity and death may result from such exposures. Causative factors have been identified. Noise exposure induces hearing losses above those secondary to the aging process. Psychophysiological effects during noise exposure are considered to result from the sympathetic activity secondary to a general stress reaction. Vibration from the use of power tools results in Raynaud's phenomenon. However, modification of power tools has reduced the symptoms associated with vibration exposure. Termination of exposure to vibration appears eventually to reduce symptoms related to white-finger spasms. Interaction between these stressors has not been clarified because of the complex effects of each. The need for additional information about the response to these stressors is evident.
- Published
- 1990
- Full Text
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21. The "effective dose" concept in older adults exposed to ozone.
- Author
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Drechsler-Parks DM, Horvath SM, and Bedi JF
- Subjects
- Administration, Inhalation, Aged, Dose-Response Relationship, Drug, Female, Forced Expiratory Volume drug effects, Humans, Male, Middle Aged, Ozone administration & dosage, Physical Exertion physiology, Respiratory Function Tests, Time Factors, Vital Capacity drug effects, Vital Capacity physiology, Aging physiology, Lung drug effects, Ozone pharmacology
- Abstract
Previous research on young adults has indicated that the magnitude of pulmonary function decrements induced by exposure to ambient ozone (O3) is related to the effective dose of O3 inhaled. The effective dose is defined as the product of O3 concentration (in ppm), mean minute ventilation (VE) and duration of exposure (min). The relative contributions of the three components of effective dose to the development of pulmonary function decrements in older adults are unknown. Twelve healthy, nonsmoking men and women (60-79 years) participated in each of four experiments: (1) a 1-h continuous exercise protocol, and (2) a 2-h intermittent exercise protocol, each performed while exposed to filtered air (FA), and to 0.45 ppm O3, resulting in different effective doses of O3. Pulmonary function (forced vital capacity, FVC, functional residual capacity, FRC, and associated calculated parameters) was measured pre- and postexposure. Ozone exposure induced significant decrements in forced expiratory volume in 0.5, 1.0 and 3.0 seconds (FEV0.5, 1.0, 3.0), regardless of the exercise protocol. There were no changes in FVC with any exposure protocol. There were significant decrements in forced expiratory flow rate at 25% and 50% of FVC (FEF25%, FEF50%) and in forced expiratory flow rate between 25% and 75% of FVC (FEF25-75%) with all four exposures, suggesting a fatigue effect. There were no differences between the decrements induced in FEV1.0 by O3 exposure under the two exercise protocols. The mean exercise VE was 25.3 l/min for the continuous exercise protocol, and was 25.2 l/min for the three exercise periods of the intermittent exercise protocol.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1990
- Full Text
- View/download PDF
22. Menstrual status and validation of body fat prediction in athletes.
- Author
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Loucks AB, Horvath SM, and Freedson PS
- Subjects
- Adult, Body Water, Female, Humans, Running, Adipose Tissue metabolism, Menstruation, Sports
- Published
- 1984
23. Accuracy and precision of matching inspired lung volume.
- Author
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Gliner JA, Folinsbee LJ, and Horvath SM
- Subjects
- Adult, Differential Threshold, Female, Humans, Male, Perception, Tidal Volume, Kinesthesis, Respiration
- Published
- 1981
- Full Text
- View/download PDF
24. Age-related metabolic modifications in male F344 rats.
- Author
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Kiang-Ulrich M and Horvath SM
- Subjects
- Animals, Male, Oxygen Consumption drug effects, Rats, Rats, Inbred F344, Aging, Basal Metabolism drug effects, Body Temperature drug effects, Tyramine pharmacology
- Abstract
Basal metabolic rate, basal colonic temperature, and response to intraperitoneal injection of tryamine were examined in three age groups: young (3 months), adult (12 months), and old (24 months) of male Fischer 344 rats. Basal metabolic rate of sedentary male F344 rats decreased significantly between 3 months (21.5 ml O2 X kg-1 X min-1) and 1 year (19.4 ml) of age and continued to decrease in the oldest animals (19.0 ml). The decrease between 1 and 2 years was not statistically significant. Basal colonic temperature showed a step-wise significant increase with age. Mean colonic temperature was 36.7 degrees C at 3 months, 37 degrees C at 1 year, and 37.5 degrees C at 2 years. Higher optimal doses of tyramine were required for 1- and 2-year-olds than for 3-month-olds. The optimal dose was 2 mg X kg-1 for 3-month-olds and 5 mg X kg-1 for 1- and 2-year-olds. Although the optimal dosages were the same for the 1- and 2-year-olds, 2-year-olds had lower peak response and the response was slower than for the 1-year-olds.
- Published
- 1984
- Full Text
- View/download PDF
25. Responses to exercise in a hot environment as related to the menstrual cycle.
- Author
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Wells CL and Horvath SM
- Subjects
- Blood Proteins, Body Temperature, Body Temperature Regulation, Environmental Exposure, Female, Heart Rate, Hematocrit, Hemoglobinometry, Humans, Lactates blood, Oxygen Consumption, Skin Temperature, Stress, Physiological, Sweating, Water-Electrolyte Balance, Hot Temperature, Menstruation, Physical Exertion
- Published
- 1974
- Full Text
- View/download PDF
26. Starvation suppresses sympathoadrenal medullary response to cold exposure in rats.
- Author
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Avakian EV and Horvath SM
- Subjects
- Animals, Epinephrine blood, Epinephrine metabolism, Male, Myocardium metabolism, Norepinephrine blood, Norepinephrine metabolism, Rats, Spleen metabolism, Adrenal Medulla physiology, Cold Temperature, Food Deprivation physiology, Sympathetic Nervous System physiology
- Abstract
The effect of 2 days (55 h) of starvation on the functional state of the sympathetic nervous system (SNS) and adrenal medulla in male rats was evaluated in both normal (24 degrees C) and cold (4 degrees C) environments. Fasting (24 degrees C) significantly decreased NE turnover in heart and spleen, and the concentration of plasma epinephrine (E) and norepinephrine (NE). Cold exposure in the fed animals significantly increased NE turnover in the heart and plasma E, but had no effect on plasma NE or spleen NE turnover compared to normal (no stress) conditions. Cardiac NE turnover was 50% less in fasted cold-stressed animals than in fed cold-stressed animals. Plasma E remained at low levels. Plasma concentration of free fatty acids was significantly elevated in the fasted state in both warm and cold environments. These results suggest that 2 days of starvation in adult male rats suppresses the activity of the SNS and adrenal medulla and interferes with the normal adrenergic response to cold stress. Moreover, E appears not to be essential for mobilization of fat stores for energy metabolism in the fasted state in either warm or moderately cold environments.
- Published
- 1981
- Full Text
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27. Effects of exhaustive exercise on the sleep of men and women.
- Author
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Bunnell DE, Bevier W, and Horvath SM
- Subjects
- Adult, Cardiac Output, Female, Heart Rate, Humans, Hydrocortisone urine, Male, Physical Exertion, Sleep physiology
- Published
- 1983
- Full Text
- View/download PDF
28. Exercise and mitochondrial calcium transport in the BIO 14.6 hamster.
- Author
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Tate CA, McMurray RG, Riggs CE, Setaro F, and Horvath SM
- Subjects
- Adenosine Triphosphate metabolism, Animals, Biological Transport, Active, Cricetinae, Female, Lactates blood, Mesocricetus, Calcium metabolism, Mitochondria, Muscle metabolism, Muscular Dystrophy, Animal metabolism, Physical Exertion, Swimming
- Abstract
To examine the effects of exhaustive swimming in normal and myopathic hamsters on muscle mitochondrial Ca2+ metabolism, sedentary normal and BIO 14.6 dystrophic Syrian hamsters swam individually in 35 degree C water until exhaustion occurred. Although the normal hamsters swam three times longer than did the BIO 14.6 hamsters, both swimming groups had a comparable two-fold increase in blood lactate. Contrary to exhaustive running, exhaustive swimming did not significantly affect mitochondrial Ca2+ uptake in either cardiac or skeletal muscle, regardless of the disease state. However, in general, the coefficients of variation for mitochondrial Ca2+ metabolism increased as a function of exercise, with the BIO 14.6 swimmers more variable than the normal swimmers. This suggests that the mitochondrial Ca2+ uptake process may be affected in some manner by exhaustive swimming, so that deviations from the norm are more apparent. The results provide further evidence that mitochondrial Ca2+ metabolism adapts to the specific type of exercise utilized to produce exhaustion.
- Published
- 1980
- Full Text
- View/download PDF
29. Enhancement of exercise performance with inhaled albuterol.
- Author
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Bedi JF, Gong H Jr, and Horvath SM
- Subjects
- Adolescent, Adult, Clinical Trials as Topic, Double-Blind Method, Female, Humans, Male, Oxygen Consumption drug effects, Placebos, Random Allocation, Respiratory Function Tests, Albuterol pharmacology, Bicycling, Physical Endurance drug effects, Sports
- Abstract
The use of bronchodilators in athletic competition has allowed asthmatics to participate successfully in competitive events. Little information exists regarding possible bronchodilator use by non-asthmatic competitive athletes. Fifteen non-asthmatic cyclists participated in a double-blind, randomized, cross-over protocol involving a simulated race, i.e., one-hour heavy continuous exercise (minute ventilation (VE) 81 L/min BTPS) followed by maximal effort workload to exhaustion, with/without prior inhalation of albuterol to see if their exercise performance would be acutely altered. Each study day metabolic parameters were obtained four times. Pulmonary function tests were performed prior to and after the inhalant (albuterol/placebo) and following exercise. There was a significant increase in forced expiratory flow parameters following albuterol. Although not significant, oxygen uptake (VO2) and VE were smaller during the one-hour submaximal test following albuterol and VO2max and VEmax were higher. There was an increased ride time (196 vs. 159 s; p less than 0.05). Albuterol may provide a competitive advantage for non-asthmatic athletes who might use it.
- Published
- 1988
30. Pulmonary function responses of older men and women to ozone exposure.
- Author
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Drechsler-Parks DM, Bedi JF, and Horvath SM
- Subjects
- Adult, Aged, Female, Forced Expiratory Volume, Humans, Lung physiology, Male, Middle Aged, Vital Capacity, Aging physiology, Lung drug effects, Ozone adverse effects
- Abstract
The pulmonary function of 8 men and 8 women (51 to 76 years of age), all nonsmokers, was measured before and after 2-h exposures to filtered air (FA) and 0.45 ppm ozone (O3). The subjects alternated 20-min periods of rest and 20-min periods of cycle ergometer exercise at a workload predetermined to elicit a ventilatory minute ventilation (VE) of approximately 25 L/min (BTPS). Functional residual capacity (FRC) was determined pre- and post-exposure. Forced vital capacity (FVC) was determined before and after exposure, and 5 min after each exercise period. Ventilatory minute volume (VE) was measured during the last 2 min of each exercise period, and heart rate was monitored throughout each exposure. The pulmonary function data were evaluated as the percentage change from pre- to post-exposure to partially remove the effect of differences between men and women in absolute lung volume. There were no statistically significant (p greater than 0.05) differences between the responses of men and women to FA or O3 exposure. There were no significant (p greater than 0.05) changes in any variable consequent to FA exposure. Exposure to O3 induced significant (p less than 0.01) decrements in FVC, FEV1.0, and FEV3.0 at post-exposure compared to pre-exposure. Ozone exposure induced no significant (p greater than 0.05) effect on FEF25-75% or FEF75%. Men had a significantly (p less than 0.05) higher mean exercise VE than women (27.9 +/- 0.29 L vs. 25.4 +/- 0.8 L; mean +/- SD). Since the men and women had similar decrements in pulmonary function, even though the women inhaled less O3, the data suggest that women may be somewhat more responsive to O3 than men. We also compared the responses of our older subjects with those of young men and women that we studied with the same protocol, and with published results of other investigators who have studied young men and women. This comparison suggests that older individuals may be less responsive to O3 than young individuals.
- Published
- 1987
- Full Text
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31. Age, smoking habits, heat stress, and their interactive effects with carbon monoxide and peroxyacetylnitrate on man's aerobic power.
- Author
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Raven PB, Drinkwater BL, Horvath SM, Ruhling RO, Gliner JA, Sutton JC, and Bolduan NW
- Subjects
- Adult, Age Factors, Analysis of Variance, Body Temperature Regulation, Carbon Monoxide pharmacology, Heart Rate drug effects, Humans, Male, Middle Aged, Nitrates pharmacology, Stress, Physiological, Air Pollutants pharmacology, Hot Temperature, Respiration drug effects, Smoking
- Published
- 1974
- Full Text
- View/download PDF
32. Prediction of pulmonary residual volume from anthropometric measurements in Caucasian male adults.
- Author
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Nigorikawa T, Oishi K, and Horvath SM
- Subjects
- Adult, Body Composition, Densitometry, Humans, Male, Middle Aged, Anthropometry methods, Lung Volume Measurements, Residual Volume
- Published
- 1988
- Full Text
- View/download PDF
33. Heat tolerance and aging.
- Author
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Drinkwater BL and Horvath SM
- Subjects
- Adolescent, Adult, Aged, Child, Female, Heart Rate, Humans, Middle Aged, Oxygen Consumption, Plasma Volume, Skin Temperature, Sweating, Acclimatization, Aging, Hot Temperature
- Abstract
Although children and older adults appear more susceptible to heat stress, the mechanisms responsible for their lower tolerance are not fully understood. Many studies dealing with the effect of age on temperature regulation have concluded that an inadequate sweating response is primarily responsible for the low tolerance of children and the elderly to exercise in the heat. However, the dependence of core temperature on relative exercise intensity and sweat rate on absolute exercise intensity makes it difficult to avoid the confounding effects of exercise on thermoregulation when aerobic power (Vo2max) varies across age groups. When 38 non-acclimatized females, ages 12 to 68 years, exercised at 30-35% Vo2max in the heat, the degree of cardiovascular stability was the primary predictor of tolerance time. Age was not a significant predictor. However, it was evident that individuals at either end of the age continuum were more likely to be at risk. For children this risk was associated with the instability of an immature cardiovascular system; for older women, a marked decrement in aerobic power. Sweat rate added significantly to the prediction of tolerance time for all subjects regardless of age. Whether the decrease in responsiveness of sweating noted for some older individuals is an age related change or a reflection of their lower fitness levels is not known.
- Published
- 1979
34. Physiological adjustments of women to prolonged work during acute hypoxia.
- Author
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Wagner JA, Miles DS, and Horvath SM
- Subjects
- Acclimatization, Adult, Altitude, Body Temperature Regulation, Catecholamines urine, Electrocardiography, Female, Heart physiology, Humans, Lactates blood, Respiration, Sex Factors, Hypoxia physiopathology, Physical Exertion
- Abstract
Five women (23-32 yr) performed bicycle work in a hypobaric chamber for 2 h at 41% of their respective altitude maximal oxygen uptakes (VO2) at 758, 586, 523, and 446 Torr barometric pressures (PB). Steady-state VO2 was achieved within 5 min work at all altitudes. Pulmonary ventilation (29.2 +/- 1.9 (mean +/- SE) 1/min, BTPS), respiratory rate (22 +/- 2 breaths/min), cardiac output (8.5 +/- 1.4 1/min), heart rate (115 +/- 6 beats/min), and stroke volume (75 +/- 13 ml) were similar at all altitudes, but time-related changes differed with altitude. Blood lactates did not change with work duration and were similar at 758 and 586 Torr PB but progressively elevated at 523 and 446 Torr. Blood norepinephrine, measured only at 758 and 446 Torr PB, increased with work but not altitude; epinephrine increased only at altitude. Norepinephrine levels and respiratory, cardiovascular, and thermoregulatory functions were essentially dependent on relative work load; blood lactates and epinephrine levels were not. Many physiological functions in these women performing sustained light work during acute altitude exposure were remarkably stable in contrast to previously reported studies on men.
- Published
- 1980
- Full Text
- View/download PDF
35. Air pollution, exercise, and heat stress.
- Author
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Drinkwater BL, Raven PB, Horvath SM, Gliner JA, Ruhling RO, Bolduan NW, and Taguchi S
- Subjects
- Analysis of Variance, Atmosphere Exposure Chambers, Body Temperature, Carbon Monoxide pharmacology, Carboxyhemoglobin analysis, Heart Rate drug effects, Humans, Male, Nitrogen Oxides pharmacology, Oxygen Consumption, Peroxides pharmacology, Respiratory Function Tests, Skin Temperature, Smoking, Air Pollution, Hot Temperature, Physical Exertion, Respiration drug effects
- Published
- 1974
- Full Text
- View/download PDF
36. Longitudinal case study of pulmonary function response to ozone.
- Author
-
Bedi JF and Horvath SM
- Subjects
- Longitudinal Studies, Aging, Lung drug effects, Ozone adverse effects
- Published
- 1987
- Full Text
- View/download PDF
37. Sleep at altitude.
- Author
-
Miller JC and Horvath SM
- Subjects
- Adolescent, Adult, Altitude Sickness physiopathology, Catecholamines urine, Diuresis, Electroencephalography, Electrooculography, Female, Humans, Male, Sex Factors, Sleep Stages, Time Factors, Altitude, Sleep physiology
- Abstract
The effects of hypobaric hypoxia upon the electrophysiologically assessed sleep of four male and four female subjects--18-29 years old--were measured during two successive nights at 493 torr (3500 m) in a hypobaric chamber. Five subjects experienced varied levels of acute mountain sickness (AMS). Sleep disturbance was primarily manifested as "insomnia" in two subjects experiencing higher levels of AMS. Relatively normal amounts of synchronized sleep were observed at 493 torr, implying the occurrence of sleep hypoventilation.
- Published
- 1977
38. Fluorometric analysis of epinephrine and norepinephrine.
- Author
-
Campuzano HC, Wilkerson JE, and Horvath SM
- Subjects
- Acetates, Drug Stability, Evaluation Studies as Topic, Humans, Hydrochloric Acid, Hydrogen-Ion Concentration, Indicators and Reagents, Methods, Perchlorates, Spectrometry, Fluorescence, Time Factors, Epinephrine analysis, Norepinephrine analysis
- Published
- 1975
- Full Text
- View/download PDF
39. Hypoxia, smoking history, and exercise.
- Author
-
Wagner JA, Horvath SM, Andrew GM, Cottle WH, and Bedi JF
- Subjects
- Adult, Aerospace Medicine, Blood Pressure, Cardiac Output, Humans, Male, Oxygen Consumption, Hypoxia physiopathology, Physical Exertion, Smoking physiopathology
- Abstract
Six nonsmokers and six cigarette smokers, 22-34 years old, performed bicycle work (53% sea level VO2 max) for 30 min in an altitude chamber under four conditions: SL, simulated sea level (PIO2 = 159 torr, PB = 523 torr) with 0.5% HbCO; SLCO, simulated sea level with 4.2% HbCO; and ACO, altitude with 4.2% HbCO. During work at altitude, heart rate (HR), minute ventilation and tidal volume increased and diastolic blood pressures decreased relative to SL. Cardiac output (Qc), stroke volume (SV), and arterial-mixed venous oxygen difference (a--vO2) were similar in smokers and nonsmokers at SL, SLCO, and A. At ACO, nonsmokers increased Qc and SV and decreased a--vO2, but these were not influenced in the smokers. Smokers showed a graded increase in HR when exposed to work in SLCO, A, and ACO. Their lower finger temperatures during A and ACO suggested vasoconstriction in the extremities. Cigarette smokers may be partially adapted to hypoxia.
- Published
- 1978
40. Exercise in a cold environment.
- Author
-
Horvath SM
- Subjects
- Cardiovascular Diseases physiopathology, Child, Endocrine Glands physiology, Environmental Exposure, Humans, Hypothermia physiopathology, Immersion adverse effects, Lung Diseases physiopathology, Male, Muscles physiology, Oxygen Consumption, Physical Endurance, Physical Fitness, Cold Temperature, Physical Exertion
- Published
- 1981
41. Sweating sensitivity and capacity of women in relation to age.
- Author
-
Drinkwater BL, Bedi JF, Loucks AB, Roche S, and Horvath SM
- Subjects
- Adult, Body Temperature, Body Temperature Regulation, Female, Forearm blood supply, Heart Rate, Hot Temperature, Humans, Middle Aged, Regional Blood Flow, Stress, Physiological physiopathology, Aging, Sweating
- Abstract
Ten postmenopausal and ten younger women rested for 2 h in a 40 degrees C, 22.2-Torr vapor pressure environment. Sweating response was monitored by resistance hygrometry for onset, a platform balance for whole-body sweat rate, and five individual capsules for regional sweat rate. Other variables measured included forearm blood flow, heart rate (HR), mean skin (Tsk) and rectal (Tre) temperatures, sweat electrolytes (Na+ and K+), oxygen uptake, and plasma volume changes. Preliminary tests included maximal aerobic power (VO2max) and percent body fat. Heat stress did not elicit any significant differences in sweating response between age groups. Indices of heat strain, Tre and HR, were also similar for both groups. The only significant difference between younger and older women was a higher Na+ concentration in the forearm sweat of postmenopausal women. No thermoregulatory responses were related to age, but both sweat rate (r = 0.48) and peak Tsk (r = -0.43) were related to VO2max. For healthy, active, older women aging did not diminish the functional capacity of the sweating mechanism to cope with heat stress while resting in this specific thermal environment.
- Published
- 1982
- Full Text
- View/download PDF
42. Adaptations in man's adrenal function in response to acute cold stress.
- Author
-
Wilkerson JE, Raven PB, Bolduan NW, and Horvath SM
- Subjects
- Adult, Blood Proteins, Diuresis, Epinephrine blood, Epinephrine urine, Hematocrit, Hemoglobinometry, Humans, Hydrocortisone blood, Hydrocortisone urine, Male, Norepinephrine blood, Norepinephrine urine, Time Factors, Adaptation, Physiological, Adrenal Glands metabolism, Cold Temperature, Hydrocortisone metabolism, Stress, Physiological
- Published
- 1974
- Full Text
- View/download PDF
43. Exercise-induced stress responses of amenorrheic and eumenorrheic runners.
- Author
-
Loucks AB and Horvath SM
- Subjects
- Adolescent, Adult, Amenorrhea psychology, Body Composition, Body Temperature Regulation, Epinephrine blood, Female, Follicle Stimulating Hormone blood, Gonadal Steroid Hormones blood, Hemodynamics, Humans, Luteinizing Hormone blood, Norepinephrine blood, Oxygen Consumption, Prolactin blood, Respiration, Running, Stress, Physiological psychology, Amenorrhea blood, Physical Exertion, Stress, Physiological blood
- Abstract
The role of stress in exercise-associated amenorrhea was investigated. Sex hormones [FSH, LH, androstenedione (A), testosterone, estrone, and 17 beta-estradiol (E2)], stress hormones [dehydroepiandrosterone, cortisol (F), PRL, norepinephrine, and epinephrine] and psychological status (Profile of Mood States and State-Trait Anxiety Inventory) were measured at rest and in response to a 40-min 80% of maximal aerobic power (VO2max) run in highly trained eumenorrheic (n = 8) and amenorrheic (n = 7) women runners matched for fatness [eumenorrheic, 16.5 +/- 2.3% (+/- SD); amenorrheic, 14.9 +/- 4.8] and maximal aerobic power (eumenorrheic, 58.9 +/- 5.7 ml/kg X min; amenorrheic, 59.8 +/- 4.6). Eumenorrheic runners were tested between days 3 and 8 of the follicular phase. At rest, decreased plasma FSH, LH, and E2 concentrations were found in amenorrheic women [eumenorrheic FSH, 10.5 +/- 4.1 mIU/ml; amenorrheic FSH, 4.9 +/- 1.6 (P less than 0.01); eumenorrheic LH, 14.1 +/- 6.1 mIU/ml; amenorrheic LH, 5.1 +/- 1.7 (P less than 0.01); eumenorrheic E2, 20 +/- 9 pg/ml; amenorrheic E2, 7 +/- 6 (P less than 0.05)]. Other sex and stress hormones and psychological measurements were similar in the two groups and were within the normal range. Ventilatory, cardiovascular, thermoregulatory, and psychological responses to the submaximal run were identical. Among eumenorrheic women, all stress hormones and A increased after exercise, but PRL, F, and A were unchanged among amenorrheic women. Estrone, E2, and testosterone did not change in either group. These observations are inconsistent with a general stress hypothesis of exercise-associated amenorrhea as well as with more specific hyperprolactinemic and hyperandrogenic hypotheses. In amenorrheic women, failure of PRL to increase in response to exercise may be due to their lack of E2, while failure of F and A to increase may indicate reduced adrenal 3 beta-hydroxysteroid dehydrogenase/isomerase activity.
- Published
- 1984
- Full Text
- View/download PDF
44. Perceptual cues used in reproduction of inspired volume.
- Author
-
Folinsbee LJ, Gliner JA, and Horvath SM
- Subjects
- Differential Threshold, Female, Humans, Lung Volume Measurements, Male, Cues, Kinesthesis, Perception, Respiration
- Published
- 1982
- Full Text
- View/download PDF
45. Physiological adaptations to thermal stress in tropical Asians.
- Author
-
Duncan MT and Horvath SM
- Subjects
- Adult, Asian People, Body Temperature, Body Weight, China ethnology, Heart Rate, Humans, India ethnology, Malaysia, Male, White People, Acclimatization, Hot Temperature, Physical Exertion, Stress, Physiological physiopathology, Tropical Climate
- Abstract
Young sedentary adult males of Malay, Indian, and Chinese origin who had established continuous residence in tropical Malaysia and presumed to be naturally acclimatized to heat, were studied to evaluate their physiological responses to a standard heat stress test. The Malay and Indian races have evolved in hot and humid geographical zones, whereas the Chinese originated from a temperate area. Subjects exercised at 50% VO2max alternating 18 minutes walking and 2 min rest during a 2-h exposure to an ambient of 34.9 degrees C dry bulb and 32.1 degrees C wet bulb. Heart rates, core and skin temperatures, sweat rates, and oxygen uptakes were measured during the heat exposure. The subjects of Malay origin exhibited the least circulatory stress of the three ethnic groups. The data obtained on these long-term residents of a hot-wet climate and who were considered acclimatized to this environment were compared to experimental data obtained by other investigators and other ethnic groups.
- Published
- 1988
- Full Text
- View/download PDF
46. A mathematical model of the human temperature regulatory system--transient cold exposure response.
- Author
-
Gordon RG, Roemer RB, and Horvath SM
- Subjects
- Blood Circulation, Environmental Exposure, Feedback, Humans, Mathematics, Models, Biological, Skin Physiological Phenomena, Skin Temperature, Body Temperature Regulation, Cold Temperature
- Published
- 1976
- Full Text
- View/download PDF
47. Heat tolerance of female distance runners.
- Author
-
Drinkwater BL, Kupprat IC, Denton JE, and Horvath SM
- Subjects
- Acclimatization, Adult, Female, Heart Rate, Humans, Running, Sports Medicine, Body Temperature Regulation, Hemodynamics, Hot Temperature, Physical Exertion, Stress, Physiological physiopathology
- Published
- 1977
- Full Text
- View/download PDF
48. Ileostomy of the distal end of the bypassed intestine in a patient with jejunoileal bypass for obesity.
- Author
-
Preston FW, Svoboda AC Jr, and Horvath SM
- Subjects
- Bacteroides Infections complications, Blind Loop Syndrome surgery, Colon surgery, Drainage, Female, Humans, Ileum, Jejunum surgery, Middle Aged, Postoperative Complications surgery, Ileostomy, Obesity therapy
- Abstract
Ileostomy of the distal end of the bypassed segment of small intestine was done twenty-three months after a 28 to 20 cm (12 to 8 inch) end-to-end jejunoileal bypass for obesity (Scott operation) in a forty-eight year old white female, thus creating a Thiry fistula. Weight prior to jejunoileal bypass was 130 kg (287 pounds). Before ileostomy it had stabilized at 80.3 kg (177 pounds). Indications for ileostomy were three episodes of blind loop syndrome and three episodes of severe bleeding from the ileotransverse colostomy anastomotic site. Culture of the bypassed segment at laparotomy revealed bacteroides, clostridia, and other anaerobes as well as the usual aerobic large bowel flora. After ileostomy the bypassed segment contained no anaerobic bacteria. Daily fluid output from the ileostomy has decreased with time, averaging 436 ml per day for the first postileostomy month and 50 ml per day for the ninth month. Beneficial effects of the ileostomy include: (1) better sense of well being; (2) no further episodes of blind loop syndrome or intestinal bleeding; and (3) cessation of anal itching. Nine months after ileostomy, hyperoxaluria and acquired megacolon were present. Weight was 5.9 kg (13 pounds) greater than before ileostomy.
- Published
- 1978
- Full Text
- View/download PDF
49. Pulmonary response to threshold levels of sulfur dioxide (1.0 ppm) and ozone (0.3 ppm).
- Author
-
Folinsbee LJ, Bedi JF, and Horvath SM
- Subjects
- Adult, Drug Interactions, Humans, Lung physiology, Lung Volume Measurements, Male, Physical Exertion, Respiration drug effects, Air Pollutants toxicity, Lung drug effects, Ozone toxicity, Sulfur Dioxide toxicity
- Abstract
We exposed 22 healthy adult nonsmoking male subjects for 2 h to filtered air, 1.0 ppm sulfur dioxide (SO2), 0.3 ppm ozone (O3), or the combination of 1.0 ppm SO2 + 0.3 ppm O3. We hypothesized that exposure to near-threshold concentrations of these pollutants would allow us to observe any interaction between the two pollutants that might have been masked by the more obvious response to the higher concentrations of O3 used in previous studies. Each subject alternated 30-min treadmill exercise with 10-min rest periods for the 2 h. The average exercise ventilation measured during the last 5 min of exercise was 38 1/min (BTPS). Forced expiratory maneuvers were performed before exposure and 5 min after each of the three exercise periods. Maximum voluntary ventilation, He dilution functional residual capacity, thoracic gas volume, and airway resistance were measured before and after the exposure. After O3 exposure alone, forced expiratory measurements (FVC, FEV1.0, and FEF25-75%) were significantly decreased. The combined exposure to SO2 + O3 produced similar but smaller decreases in these measures. There were small but significant differences between the O3 and the O3 + SO2 exposure for FVC, FEV1.0, FEV2.0, FEV3.0, and FEF25-75% at the end of the 2-h exposure. We conclude that, with these pollutant concentrations, there is no additive or synergistic effect of the two pollutants on pulmonary function.
- Published
- 1985
- Full Text
- View/download PDF
50. Blood biochemical alterations during recovery from competitive marathon running.
- Author
-
Maron MB, Horvath SM, and Wilkerson JE
- Subjects
- Blood Glucose, Blood Proteins, Epinephrine blood, Fatty Acids, Nonesterified, Glycerol blood, Hematocrit, Hemoglobins, Humans, Hydrocortisone blood, Lactates blood, Male, Norepinephrine blood, Pyruvates blood, Sodium blood, Time Factors, Triglycerides blood, Water-Electrolyte Balance, Blood Physiological Phenomena, Physical Exertion, Running, Sports Medicine
- Abstract
The occurrence of possible prolonged alterations in plasma levels of cortisol, epinephrine, norepinephrine, selected energy metabolites, and water and electrolyte balance was assessed in six highly trained male marathon runners by measuring blood biochemical constituents on the 10th day before and for the three days following the running of a marathon. Post-race changes in hemoglobin, hematocrit, and protein levels indicated that a hemodilution had occurred, possibly as a result of elevated sodium levels. Epinephrine remained elevated until the second day. Cortisol was depressed on the first and third post-race days while variable levels were observed on the second day. No prolonged alterations were noted in norepinephrine, FFA, glycerol, triglycerides, glucose, lactate, and pyruvate.
- Published
- 1977
- Full Text
- View/download PDF
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