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At least 1,099 records · Page 61Linked to original sources
PubMed1982

Postexercise blood pressure as a predictor of hypertension.

A study on 721 healthy male aircrew assessed whether the blood pressure response to exercise could be used to predict the development of hypertension. A positive blood pressure response to exercise, recorded 30 s after the completion of exercise, was defined as a systolic blood pressure of 200 torr or more (systolic test) or a raised diastolic blood pressure (diastolic test). While 236 (32.7%) became hypertensive with a blood pressure greater than 149/90 torr, 17% of these had shown a positive systolic response and 17% a positive diastolic response. The other 485 individuals (67.3%) remained normotensive throughout the mean follow-up period of 68 months (range 12-170 months). Of this group, 88% never manifested a positive systolic or diastolic response to exercise. Although 5% of the normotensive subjects manifested a positive systolic response to exercise, and 12% manifested a positive diastolic response to exercise, a longer period of follow-up may reduce this figure. It is concluded that exercise related blood pressure is a useful test in predicting the development of essential hypertension.

Adult↗
PubMed1994

[Changes in the endotheliocyte activity of the coronary vessels under the influence of stress].

The effect of saponin and blockade of the nitrogen oxide upon the coronary endothelium was found in rats subjected to a 6-hrs stress. The damage of the endothelium and the blockade abolished the stressor-induced increase in the coronary blood flow velocity. The index of autoregulation and the latter's efficiency, however, remained the same. Preliminary administration of L-arginine prevented the effect of NG-monomethyl-L-arginine upon the coronary flow in the isolated hearts of rats subjected to stress. The post-stressor increase in the coronary blood flow seems to be due to an increase in releasing the nitrogen oxide from the coronary vessels' endotheliocytes.

Animals↗
PubMed1995

Effect of triazolam on responses to a cold-water immersion in humans.

Managing alertness of soldiers during sustained operations is a source of serious concern for military unit commanders. A frequently employed strategy is to induce sleep before an operation, especially operations requiring prolonged travel. Sleep-inducing drugs could have an action on thermoregulation through their effect on alertness and a possible direct effect on the brain. The goal of this study was therefore to evaluate the effect of a commonly prescribed triazolam (Halcion) on thermoregulatory responses to cold-water immersion. Eight subjects were immersed twice in 18 degrees C water for up to 90 min in the morning; once after ingesting 0.25 mg triazolam (TRZ) the prior evening, and again after placebo (PLB) treatment. There were no significant differences between trials for mean duration of the immersion, the change in rectal temperature and mean skin temperature. Total metabolic heat production was similar for both conditions: 767 +/- 107 vs. 781 +/- 105 kj.m-2 for TRZ and PLB, respectively. The results should be considered in light of a large variation among the subjects in sensitivity to TRZ, which was unrelated to biometrical characteristics such as surface area-to-mass ratio, lean body mass, % body fat, and physical fitness. Although not statistically significant, there was a trend for a smaller increase in plasma free fatty acid and glycerol concentrations after water immersion with TRZ. The results suggest that the ingestion of a single dose of triazolam 11 h prior to a cold-water immersion is not likely to accelerate the rate of onset of hypothermia. Individual sensitivity, however, may predispose some sensitive subjects to negative effects in this regard.

Adipose Tissue↗
PubMed1995

Measurement of upper airway pressures in exercising horses with dorsal displacement of the soft palate.

To determine whether abnormal airway pressures have a role in development of dorsal displacement of the soft palate (DDSP), measurements of tracheal and pharyngeal pressures were correlated with nasopharyngeal morphology in exercising horses. Exercising videoendoscopy and measurement of tracheal and pharyngeal pressures were used in 14 clinically normal horses and 19 horses with intermittent DDSP. The pressure signals were superimposed on the videoendoscope image, and both images were saved simultaneously on a videocassette for slow motion analysis to determine the instant displacement occurred in the respiratory cycle. Horses were submitted to an escalating 8-minute high-speed test with a maximal speed of 14 m/s. Compared with clinically normal horses, horses with intermittent DDSP did not have excessively negative inspiratory pressures during exercise. Eight horses displaced the soft palate during inspiration, 4 horses displaced it during expiration, and 7 displaced it by swallowing. Some horses displaced the soft palate at the beginning of the exercise trial, before reaching maximal speed, some horses displaced it at the peak speed, and some horses displaced it when slowing down. Epiglottic size in horses with DDSP was within normal limits, ruling out epiglottic hypoplasia as a cause of DDSP during exercise. Airway pressures were significantly (P < 0.002) altered after DDSP. Pharyngeal and tracheal inspiratory pressures were less negative, whereas pharyngeal expiratory pressure became less positive and tracheal expiratory pressure became more positive after displacement, suggesting a decrease in airflow and an increase in expiratory resistance in the upper airway.

Airway Obstruction↗
PubMed1994

Intraruminal fluid administration to goats: effects of handling and fluid temperature.

Physiological stress response to intraruminal fluid administration was studied in 5 female goats. The fluid was given through a stomach tube. The water was cold (10 degrees C) or warm (38 degrees C) and in an amount of 7.5-10% of body weight. Plasma concentrations of adrenaline, noradrenaline and cortisol increased significantly after both treatments. Adrenaline and noradrenaline responses were greater and more longlasting after cold water administration, but there was no difference in cortisol response between cold and warm water. Haematocrit and plasma protein concentrations increased also and the effects of cold water lasted longer. Blood pressure showed a sharp rise of short duration and was independent of water temperature. The immediate tachycardiac response was similar with both treatments, but cold water caused an additional peak 15 min later. The cooling did not increase plasma histamine level. The results suggest that stomach intubation and administration of water into the rumen leads to strong activation of hormonal and cardiovascular stress parameters even in goats well adapted to handling. Low temperature of the fluid further heightens the effect. Warming of fluids to near body temperature before their administration is thus recommended.

Animals↗
PubMed1996

[Comparison of sevoflurane and isoflurane in ambulatory surgery. Results of a multicenter study].

UNLABELLED: A multicenter, randomized, comparative phase III study evaluating the effect of sevoflurane versus isoflurane in adult outpatients was performed. The aim of the study was to compare (1) maintenance of anaesthesia and (2) how rapidly and easily the patients emerge from the anaesthetic and recover. METHODS: Outpatients were included who underwent scheduled surgical procedures of an anticipated duration of up to 3 h and an anticipated length of hospitalization of less than 24 h post-anaesthesia. Five hundred patients were randomly selected to receive either sevoflurane (n = 247) or isoflurane (n = 253), each administered with oxygen (30-50%) in nitrous oxide. Efficacy was evaluated through the measurement of times of recovery parameters and tests like the objective pain-discomfort scale, the visual analogue scale, and the digit symbol substitution test. Safety was evaluated by monitoring adverse experience, clinical laboratory and non-laboratory testing and physical assessments. RESULTS: No statistical differences were observed between the two treatment groups with respect to demographics and ASA class. All study drug concentrations during each anaesthetic phase were statistically lower in the sevoflurane (average concentration 0.61 MAC) compared to the isoflurane (average concentration 0.70 MAC) group. The mean time to emergence was statistically shorter in the sevoflurane group (8.2 min) than in the isoflurane group (9.3 min). The mean time to response to commands (8.5 min vs 9.8 min) and the mean time to orientation (10.6 min vs 13.0 min) were also statistically shorter in the sevoflurane than in the isoflurane group. The EEG results showed a faster decrease in delta activity and a faster increase in alpha activity in the sevoflurane group than in the isoflurane group, indicating faster awakening. No statistical differences were observed between the two treatment groups for the mean time to any of the remaining post-anaesthesia events. Bradycardia was observed in a statistcally higher percentage of patients in the sevoflurane group (6%) than in the isoflurane group (2%). No other statistical differences were observed between the two treatment groups concerning the incidence of study drug-related adverse experience. The most common adverse experiences were nausea and vomiting. At all post-anaesthesia time points, higher serum inorganic fluoride concentrations were observed in the sevoflurane (maximum 30.2 mumol/l) than in the isoflurane group. No clinical or laboratory renal insufficiency was noted. Eighty-seven percent of patients in the sevoflurane group would request the same anaesthetic technique compared to only 79% of patients in the isoflurane group. CONCLUSIONS: Sevoflurane was as safe as isoflurane for anaesthesia in adult outpatients. Patients who received sevoflurane had statistically significantly shorter recovery parameters than isoflurane patients.

Adolescent↗
PubMed1998

Short-term evaluation of captopril in patients with chronic left sided valvular regurgitations.

OBJECTIVE: To evaluate the clinical effects and the changes in cardiac performance of high- and low-dose captopril compared to placebo in patients with chronic symptomatic aortic regurgitation (AR), and/or mitral regurgitation (MR). PATIENTS AND METHODS: We randomized patients into three groups, placebo (Group 1), incremental daily doses of 50 mg (Group 2), and 100 mg captopril (Group 3). We compared exercise capacity before and after four-week of treatment. RESULTS: Treatment was well tolerated with no serious side effects including blood chemistry. There were no significant effects of treatment on left ventricular dimensions nor calculated left ventricular ejection fraction (LVEF) between groups (LVEF change -0.6%, -2.6%, 2.4%, in group 1, 2 and 3 respectively; p > 0.05). No difference of exercise duration between treatment and placebo arms (change by 13%, 12.8%, 16.4%, respectively; p > 0.05). However, there were trends in the number of the patients who improved in left ventricular performance (absolute LVEF change > 5% unit = 15%, 16%, and 42% respectively; p > 0.05) and exercise performance (exercise time improvement > 75 sec = 50%, 47%, and 68% respectively; p > 0.05) in high dose captopril treatment group. CONCLUSION: There was no significant improvement of left ventricular performance and exercise capacity after four-weeks' treatment of low and high dose captopril. Further study with a larger sample size, and longer follow-up period may be required.

Adolescent↗
PubMed1998

Effect of prior lumbar discectomy on outcome of lumbar fusion: a prospective analysis using the SF-36 measure.

This study prospectively measured patient-reported quality-of-life outcome in patients undergoing fusion for recurrent symptoms after prior discectomy. Analysis of SF-36 data revealed statistically significant improvement in physical function, social function, and bodily pain 1 year postoperatively. Analysis of variance revealed significant interactions based on worker's compensation, litigation status, educational level, and age. The results support the conclusion that the SF-36 is a useful and applicable tool for measuring patient perception and quality-of-life parameters after spinal surgery. SF-36 outcomes demonstrated a reasonable level of success for lumbar fusion in revision spine surgery, with the most significant improvements noted in the categories of pain, physical function, and social function.

Adult↗
PubMed2006

Specific and nonspecific interaction forces between Escherichia coli and silicon nitride, determined by poisson statistical analysis.

The nature of the physical interactions between Escherichia coli JM109 and a model surface (silicon nitride) was investigated in water via atomic force microscopy (AFM). AFM force measurements on bacteria can represent the combined effects of van der Waals and electrostatic forces, hydrogen bonding, steric interactions, and perhaps ligand-receptor type bonds. It can be difficult to decouple these forces into their individual components since both specific (chemical or short-range forces such as hydrogen bonding) and nonspecific (long-range colloidal) forces may be present in the overall profiles. An analysis is presented based on the application of Poisson statistics to AFM adhesion data, to decouple the specific and nonspecific interactions. Comparisons with classical DLVO theory and a modified form of a van der Waals expression for rough surfaces were made in order to help explain the nature of the interactions. The only specific forces in the system were due to hydrogen bonding, which from the Poisson analysis were found to be -0.125 nN. The nonspecific forces of 0.155 nN represent an overall repulsive interaction. These nonspecific forces are comparable to the forces calculated from DLVO theory, in which electrostatic-double layer interactions are added to van der Waals attractions calculated at the distance of closest approach, as long as the van der Waals model for "rough" spherical surfaces is used. Calculated electrostatic-double layer and van der Waals interactions summed to 0.116 nN. In contrast, if the classic (i.e., smooth) sphere-sphere model was used to predict the van der Waals forces, the sum of electrostatic and van der Waals forces was -7.11 nN, which appears to be a large overprediction. The Poisson statistical analysis of adhesion forces may be very useful in applications of bacterial adhesion, because it represents an easy way to determine the magnitude of hydrogen bonding in a given system and it allows the fundamental forces to be easily broken into their components.

Bacterial Adhesion↗
PubMed1999

The relationship between psychiatric and physical health in elderly people with intellectual disability.

Elderly people with intellectual disability have high rates of both psychiatric and physical disorders. In the elderly general population, these disorders are known to be associated. Whether such an association exists amongst elderly people with intellectual disability is unclear, but the resolution of this question is of clinical as well as academic importance. Psychiatric and physical assessments were completed on 134 people with intellectual disability aged 65 years and over (93.7% of the ascertained population living in Leicestershire, UK). The relationship between the two disorders was statistically examined. The number of physical disorders, age, level of intellectual disability and smoking status were retained in the logistic regression equation which predicted caseness for dementia in 79.9%. Similar statistical modelling for psychiatric disorders (other than dementia) retained the level of intellectual disability as the only explanatory variable in the equation. These results differ from the elderly general population, but are in keeping with the one previous intellectual disability study. In view of the poor use of general medical services by elderly people with intellectual disability, knowledge of such comorbidity should alert psychiatrists to the need for physical assessments in order to optimize health.

Aged↗
PubMed2000

Exercise and weight loss in obese older adults with knee osteoarthritis: a preliminary study.

OBJECTIVE: The purposes of this pilot study were to determine if a combined dietary and exercise intervention would result in significant weight loss in older obese adults with knee osteoarthritis, and to compare the effects of exercise plus dietary therapy with exercise alone on gait, strength, knee pain, biomarkers of cartilage degradation, and physical function. DESIGN: Single-blind, two-arm, randomized clinical trial conducted for 24 weeks. SETTING: A university health and exercise science center. PARTICIPANTS: Twenty-four community-dwelling obese older adults aged > or = 60 years, body mass index > or = 28, knee pain, radiographic evidence of knee osteoarthritis, and self-reported physical disability. INTERVENTION: Randomization into two groups: exercise and diet (E&D) and exercise alone (E). Exercise consisted of a combined weight training and walking program for 1 hour three times per week. The dietary intervention included weekly sessions with a nutritionist utilizing cognitive-behavior modification to change dietary habits to reach a group goal of an average weight loss of 15 lb (6.8 kg) over 6 months. MEASUREMENTS: All measurements were conducted at baseline and 3 and 6 months, except for synovial fluid analysis, which was obtained only at baseline and 6 months. In addition, weight was measured weekly in the E&D group. Physical disability and knee pain were measured by self-report and physical performance was measured using the 6-minute walk and stair climb tasks. Biomechanical testing included kinetic and kinematic analysis of gait and isokinetic strength testing. Synovial fluid was analyzed for levels of total proteoglycan, keratan sulfate, and interleukin-1 beta. RESULTS: Twenty-one of the 24 participants completed the study, with one dropout in the E&D group and two in the E group. The E&D group lost a mean of 18.8 lb (8.5 kg) at 6 months compared with 4.0 lb (1.8 kg) in the E group (P = .01). Significant improvements were noted in both groups in self-reported disability and knee pain intensity and frequency as well as in physical performance measures. However, no statistical differences were found between the two groups at 6 months in knee pain scores or self-reported performance measures of physical function. There was no difference in knee strength between the groups, with both groups showing modest improvements from baseline to 6 months. At 6 months, the E&D group had a significantly greater loading rate (P = .03) and maximum braking force (P = .01) during gait. There were no significant between-group differences in the other biomechanical measures. Synovial fluid samples were obtainable at both baseline and 6 months in eight participants (four per group). The level of keratan sulfate decreased similarly in both groups from an average baseline of 96.8 +/- 37.1 to 71.5 +/- 23 ng/microg total proteoglycan. The level of IL-1 decreased from 25.3 +/- 9.8 at baseline to 8.3 +/- 6.1 pg/mL. The decrease in IL-1 correlated with the change in pain frequency (r = -0.77, P = .043). CONCLUSIONS: Weight loss can be achieved and sustained over a 6-month period in a cohort of older obese persons with osteoarthritis of the knee through a dietary and exercise intervention. Both exercise and combined weight loss and exercise regimens lead to improvements in pain, disability, and performance. Moreover, the trends in the biomechanical data suggest that exercise combined with diet may have an additional benefit in improved gait compared with exercise alone. A larger study is indicated to determine if weight loss provides additional benefits to exercise alone in this patient population.

Activities of Daily Living↗
PubMed1995

Physical activity, physical fitness, and coronary heart disease risk factors.

The relationships between physical activity, physical fitness, and coronary heart disease risk factors measured in a large community sample were evaluated. Self-reported physical activity using a single question, maximal oxygen consumption estimates derived from the Pawtucket Heart Health Step Test, blood pressure, nonfasting lipids, and body mass index were cross-sectionally evaluated in 381 men and 556 women. The correlation of estimated maximal oxygen consumption and self-reported physical activity was modest but statistically significant (r = 0.13 in men and r = 0.19 in women). Blood pressure, body mass index, and HDL cholesterol were correlated with physical fitness (r = 0.24-0.65) and correlated to self-reported physical activity (r = 0.09-0.14). Evaluation of coronary heart disease risk factors using both physical activity and physical fitness revealed a complex relationship that generally showed a stronger relationship with measures of physical fitness than with physical activity. This study suggests that simultaneous measurement of physical activity and physical fitness may be useful in epidemiologic studies of habitual physical activity and chronic disease.

Adolescent↗