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At least 973 records · Page 54Linked to original sources
PubMed1990

Changes in lipoprotein subfractions during diet-induced and exercise-induced weight loss in moderately overweight men.

We studied separately the effects of weight loss by calorie restriction (dieting) and by calorie expenditure (primarily, running) on lipoprotein subfraction concentrations in sedentary, moderately overweight men assigned at random into three groups as follows: exercise without calorie restriction (n = 46), calorie restriction without exercise (n = 42), and control (n = 42). Plasma lipoprotein mass concentrations were measured by analytic ultracentrifugation for flotation rates (F0(1.20), S0f) within high density lipoprotein (HDL) (F0(1.20) 0-9), low density lipoprotein (LDL) (S0f 0-12), intermediate density lipoprotein (IDL) (S0f 12-20), and very low density lipoprotein (VLDL) (S0f 20-400) particle distributions. Particle diameter and flotation rate of the most abundant LDL species were determined by nondenaturing polyacrylamide gradient gel electrophoresis and analytic ultracentrifugation, respectively. During the 1-year trial, the exercisers ran (mean +/- SD) 15.6 +/- 9.1 km/wk, and the dieters ate 340 +/- 71 fewer kilocalories per day than at baseline. Total body weight was reduced significantly more in dieters (-7.2 +/- 4.1 kg) and exercisers (-4.0 +/- 3.9 kg) than controls (0.6 +/- 3.7 kg). As compared with mean changes in controls, the exercisers and dieters significantly increased HDL2 mass (48.6% and 47.1%, respectively), decreased VLDL mass (-23.9% and -25.5%), and increased LDL peak particle diameter (2.4 and 3.2 A). When adjusted to an equivalent change in body mass index by analysis of covariance, 1) exercise-induced and diet-induced weight loss produced comparable mean changes in the mass of small LDL and VLDL, and in LDL peak particle diameter; 2) the exercisers versus control group difference in HDL2 was attributed to the exercisers' reduced body mass index; and 3) HDL2 increased significantly less in dieters than in exercisers. In dieters, low calorie intake might mitigate the effects of weight loss on HDL2.

Adult↗
PubMed2005

Physiotherapy coupled with dextroamphetamine for rehabilitation after hemiparetic stroke: a randomized, double-blind, placebo-controlled trial.

BACKGROUND AND PURPOSE: Hemiparesis is the commonest disabling deficit caused by stroke. In animals, dextroamphetamine (AMPH) paired with training enhances motor recovery, but its clinical efficacy is uncertain. METHODS: In a randomized, double-blind, placebo-controlled trial, 71 stroke patients were stratified by hemiparesis severity and randomly assigned to 10 sessions of physiotherapy coupled with either 10 mg AMPH or placebo. Study treatments were administered by 1 physiotherapist, beginning 5 to 10 days after stroke and continuing twice per week for 5 weeks. Outcomes were assessed by 1 physiotherapist at baseline, after each treatment session, at 6 weeks, and at 3 months. The primary outcome was motor recovery (impairment level) on the Fugl-Meyer (FM) scale. Secondary outcomes assessed mobility, ambulation, arm/hand function, and independence in activities of daily living. RESULTS: Baseline hemiparesis was severe overall (mean FM score 27.7+/-20.0). Motor scores improved during treatment in both groups (mean change, baseline to 3 months 29.5+/-16.6). Repeated-measures ANOVA revealed no significant differences in recovery between the treatment groups for the entire cohort (n=67) or for subgroups with a severe hemiparesis (n=43), moderate hemiparesis (n=24), or cortically based stroke (n=26). In the moderate subgroup, there was a significant drug x time interaction for upper extremity motor recovery (F=5.14; P<0.001), although there was a significant baseline imbalance in motor scores in this subgroup. CONCLUSIONS: In stroke patients with a severe motor deficit, 10 mg AMPH coupled with physiotherapy twice per week for 5 weeks in the early poststroke period provided no additional benefit in motor or functional recovery compared with physiotherapy alone. Patients with moderate severity hemiparesis deserve further investigation. Increased intensity and longer duration drug/therapy dosing regimens should be explored, targeting the upper and lower limbs separately.

Aged↗
PubMed2002

Continuous subcutaneous infusion of treprostinil, a prostacyclin analogue, in patients with pulmonary arterial hypertension: a double-blind, randomized, placebo-controlled trial.

Pulmonary arterial hypertension is a life-threatening disease for which continuous intravenous prostacyclin has proven to be effective. However, this treatment requires a permanent central venous catheter with the associated risk of serious complications such as sepsis, thromboembolism, or syncope. Treprostinil, a stable prostacyclin analogue, can be administered by a continuous subcutaneous infusion, avoiding these risks. We conducted a 12-week, double-blind, placebo-controlled multicenter trial in 470 patients with pulmonary arterial hypertension, either primary or associated with connective tissue disease or congenital systemic-to-pulmonary shunts. Exercise capacity improved with treprostinil and was unchanged with placebo; the between treatment group difference in median six-minute walking distance was 16 m (p = 0.006). Improvement in exercise capacity was greater in the sicker patients and was dose-related, but independent of disease etiology. Concomitantly, treprostinil significantly improved indices of dyspnea, signs and symptoms of pulmonary hypertension, and hemodynamics. The most common side effect attributed to treprostinil was infusion site pain (85%) leading to premature discontinuation from the study in 8% of patients. Three patients in the treprostinil treatment group presented with an episode of gastrointestinal hemorrhage. We conclude that chronic subcutaneous infusion of treprostinil is an effective treatment with an acceptable safety profile in patients with pulmonary arterial hypertension.

Adult↗
PubMed2005

Childhood trauma and personality disorder: positive correlation with adult CSF corticotropin-releasing factor concentrations.

OBJECTIVE: To test the hypothesis that early life trauma results in adult stress hormone alterations in individuals with personality disorders, the authors examined the relationship between history of childhood adversity and lumbar CSF corticotropin-releasing factor (CRF). METHOD: Participants were 20 otherwise healthy men who met DSM-IV criteria for personality disorders. CSF CRF was obtained by lumbar puncture, and childhood adversity was measured by the Childhood Trauma Questionnaire. Correlations were obtained between CSF CRF and the total score on the Childhood Trauma Questionnaire as well as scores on its four subscales. RESULTS: CSF CRF concentrations were positively correlated with the total score on the Childhood Trauma Questionnaire. Analysis of the subscales revealed that CSF CRF was correlated with emotional neglect. Correlations between CSF CRF level and physical and emotional abuse and with physical neglect were not statistically significant. CONCLUSIONS: Consistent with the hypothesis that the severity of early life stress is correlated with stress hormone abnormalities in adulthood, Childhood Trauma Questionnaire total scores and emotional neglect scores were significantly correlated with CSF CRF levels in individuals with personality disorders.

Adult↗
PubMed1988

Community health-related physical fitness testing and the National Garden Festival Health Fair at Stoke-on-Trent.

A brief review of the literature on the effectiveness of health-related fitness (HRF) tests in the promotion of exercise is presented. The paper then describes one particular community project which used HRF tests as part of exercise promotion. The purpose of such a project was to give people some indication of their present cardio-respiratory fitness, muscular strength, and flexibility with a view to highlighting the components of HRF and areas of concern for future action. Other measures, such as self-reported activity patterns, smoking, alcohol, and diet were also taken. During the six months of the Festival in 1986, over 250,000 people visited the Health Fair (HF), and 15,000 volunteered to take the fitness tests; 13,373 were actually completed. As part of the evaluation of the HRF tests at the HF, a sample of 3,000 (500 per month) was used. A follow-up survey on 350 was mailed 12 months after the end of the Festival and 173 people replied. The follow-up survey showed that just under 50 per cent of males followed their 8-week exercise programme (given to them after their HRF tests) for the recommended time period. However, this figure dropped to 21.4 per cent for females. Of those who started exercise after their HRF tests, 12.5 per cent (females) and 18.4 per cent (males) gave up within two months, otherwise most were still involved (87.5 per cent females, 71.4 per cent males) after 12 months.(ABSTRACT TRUNCATED AT 250 WORDS)

England↗
PubMed1989

Fine needle aspiration cytology and breast cancer diagnosis.

The authors report on 315 histologically confirmed consecutive breast cancer (BC) cases undergoing fine needle aspiration cytology (FNAC). Inadequate smears were infrequent (7%), particularly when reaspiration of inadequate cases was employed (1-2%). FNAC suspected BC in 81% of the total or 88% of adequate smears. Univariate and multivariate (Cox's model) analyses showed no correlation between inadequacy or suspect/positive FNAC rate and patient age, T category or histologic type. Differences in the inadequacy and suspect/positive rate were recorded among 30 operators (surgeons, oncologists, radiologists) performing the sampling, but the average results were consistent with literature reports. FNAC was found to be a useful diagnostic tool for BC diagnosis, and proper training of the highest number of operators is recommended to allow the widest diffusion of this diagnostic technique.

Adult↗
PubMed2004

Convection in containerless processing.

Different containerless processing techniques have different strengths and weaknesses. Applying more than one technique allows various parts of a problem to be solved separately. For two research projects, one on phase selection in steels and the other on nucleation and growth of quasicrystals, a combination of experiments using electrostatic levitation (ESL) and electromagnetic levitation (EML) is appropriate. In both experiments, convection is an important variable. The convective conditions achievable with each method are compared for two very different materials: a low-viscosity, high-temperature stainless steel, and a high-viscosity, low-temperature quasicrystal-forming alloy. It is clear that the techniques are complementary when convection is a parameter to be explored in the experiments. For a number of reasons, including the sample size, temperature, and reactivity, direct measurement of the convective velocity is not feasible. Therefore, we must rely on computation techniques to estimate convection in these experiments. These models are an essential part of almost any microgravity investigation. The methods employed and results obtained for the projects levitation observation of dendrite evolution in steel ternary alloy rapid solidification (LODESTARS) and quasicrystalline undercooled alloys for space investigation (QUASI) are explained.

Electromagnetic Phenomena↗
PubMed2005

Testosterone, dehydroepiandrosterone, and physical performance in older men: results from the Massachusetts Male Aging Study.

OBJECTIVE: This manuscript examines the relationships of total testosterone (T), bioavailable T, dehydroepiandrosterone (DHEA), and DHEA sulfate (DHEAS) to measures of physical performance in a large, population-based, random sample of men. METHODS: In the most recent wave of the Massachusetts Male Aging Study, measures of strength and physical performance [seven-item physical performance test (PPT), timed chair stand test, and grip strength] were made in 684 men, aged 55-85 yr. Complete hormone data were also obtained. Initial graphical exploration of performance outcomes as a function of hormone levels showed linear increases in physical performance up to certain threshold hormone concentrations, beyond which the associations were diminished. Regression models were used to estimate threshold locations and standardized regression coefficients quantifying the association between hormones and strength. RESULTS: All hormones exhibited significant age-adjusted positive association with PPT score below, but not necessarily above, the thresholds. DHEA was positively associated with chair stand score below, but was not above the threshold. None of the hormones studied was significantly associated with grip strength. CONCLUSION: Up to certain critical concentrations, elevated levels of TT, total T, bioavailable T, DHEA, and DHEA sulfate are associated with increased physical performance, as indicated by the PPT. However, levels beyond those critical concentrations, as might be achieved through exogenous supplementation, do not appear to confer any additional benefit. In general, hormone concentrations do not appear to be meaningfully associated with grip strength or chair stand scores.

Adult↗
PubMed1992

Heritability of cortisol responses to human corticotropin-releasing hormone, ergometry, and psychological stress in humans.

The present study investigated cortisol responses to three different stimulation procedures, with a focus on the contribution of genetic factors. Thirteen monozygotic (MZ) twin pairs and 11 dizygotic (DZ) twin pairs performed bicycle ergometry until exhaustion and were exposed to the psychological stress of public speaking and mental arithmetic in front of an audience. Furthermore, 9 MZ pairs and 10 DZ pairs were injected with 100 micrograms synthetic human CRH (hCRH). The adrenocortical response to these challenges was monitored by determination of cortisol in saliva. Significant intraindividual stability of baseline cortisol levels was found in females, but was less in males. Maximum cortisol responses to all three stimulation procedures were significantly intercorrelated in males, but in females only the cortisol responses to hCRH and ergometer exercise showed a significant correlation. While a decided influence of genetic factors was observed for all three baseline cortisol levels as well as for the response to hCRH, heredity appeared to be play a minor role in the adrenocortical response to psychological stress. Cortisol changes after bicycle ergometry revealed no impact of genetic factors on the secretion of cortisol in response to strenuous physical exercise.

Adolescent↗
PubMed2006

Physical fitness and lifetime cognitive change.

OBJECTIVE: To test the hypothesis that physical fitness is associated with more successful cognitive aging. METHODS: Surviving participants (N = 460) of the Scottish Mental Survey of 1932 were tested on the same general cognitive test at age 11 and 79 years. Measures of grip strength, 6-meter walk time, and lung function (forced expiratory volume from the lungs in 1 second [FEV1]) were assessed at age 79 years. RESULTS: A latent physical fitness trait, derived by principal components analysis of the three fitness measures, was significantly associated with successful cognitive aging. Cognitive score at age 11, sex, social class, and APOE-epsilon4 genotype were included as covariables. Higher childhood IQ was associated with better lung function in old age. CONCLUSIONS: Physical fitness is associated with cognitive reserve. Intervention studies aimed at making older people fitter are good candidates to improve cognitive aging.

Adaptation, Physiological↗
PubMed1982

Biological variability in maximum aerobic power.

The biological variation in maximum aerobic power (V O2max) was examined in four trained females and one trained male. An average of 8-20 repeat VO2max treadmill tests over a 2-4 wk period were performed on each subject (80 total tests). Biological variation (Si) in VO2max was computed as the standard deviation for the VO2max values for each individual, after subtracting net technological error (Se). Technological error was computed for each piece of equipment as the standard deviation of multiple trials. Results revealed that Si + Se amounted to +/- 5.6%. Biological variability accounted for 90% or more of this variability, while technological error accounted for less than 10%. In light of the magnitude of biological variation for VO2max, the necessity for securing control data when attempting to study training effects is pointed out.

Adult↗
PubMedDate not supplied

Health-related quality of life in HIV-infected naive patients treated with nelfinavir or nevirapine associated with ZDV/3TC (the COMBINE-QoL substudy).

PURPOSE: The aim of the study was to assess differences in health-related quality of life (HRQoL) in HIV-infected naive patients treated with two HAART regimens at 12 months. METHOD: The MOS-HIV questionnaire was used to measure HRQoL in a subgroup of 127 patients included in the COMBINE study, which was an open-label, randomized, multicenter study comparing zidovudine (ZDV) and lamivudine (3TC) plus nelfinavir (NFV) or nevirapine (NVP) regimens in HIV-infected naive patients. 63 patients were included in the ZDV/3TC/NFV arm and 64 in the ZDV/3TC/NVP arm. RESULTS: No statistically significant differences were observed at baseline in demographic and clinical variables and HRQoL scores between treatment groups, except that the proportion of homosexual men was higher in the ZDV/3TC/NVP arm. There were no statistically significant differences in HRQoL scores between arms at 12 months and over time; only ZDV/3TC/NVP patients showed statistically significant improvement in Physical Health Summary score (p <.01) and a trend toward a better profile in Mental Health Summary score (p =.07). Overall, patients who were treated with ZDV/3TC/NVP showed greater changes in physical dimensions and patients who were treated with ZDV/3TC/NFV showed greater changes in mental health. CONCLUSION: Differences in HRQoL between study groups at 1 year follow-up were not detected. Nevertheless, a trend toward improvement was observed in summary health scores in ZDV/3TC/NVP-treated patients.

Adult↗
PubMed1975

Myocardial ischemic effects of isometric, dynamic and combined exercise in coronary artery disease.

The electrocardiographic effects isometric (handgrip) and combined isometric-dynamic (treadmill-plus-brief-case) exercise were evaluated and compared to a submaximal treadmill stress test in 140 patients with known or suspected coronary artery disease. Only 3 of 90 patients developed ischemic ST changes during handgrip, as opposed to 25 positive treadmill tests (p less than 0.01). Of 19 of 50 patients who were positive during the standard treadmill test, only 17 showed positive findings during the combined treadmill-briefcase test. Analysis of hemodynamic responses showed significant (p less than 0.01) differences between the handgrip and treadmill tests in terms of heart rate response (control 83 plus or minus beats/minute, handgrip 105 plus or minus 4, treadmill 151 plus or minus 6), diastolic blood pressure (control 80 plus or minus 2 mm Hg, isometric 93 plus or minus 3, treadmill 81 plus or minus 3) and heart rate-systolic pressure product (control 9940 plus or minus 564 units, handgrip 15022 plus or minus 779, treadmill 22270 plus or minus 1147). In comparing treadmill and combined treadmill-briefcase tests, significant differences were seen in systolic blood pressure (control 114 plus or minus 2 mm Hg, treadmill 143 plus or minus 3, briefcase 155 plus or minus 3), diastolic blood pressure (control 83 plus or minus 2 mm Hg, treadmill 82 plus or minus 2, briefcase 89 plus or minus 2) and rate-pressure product (control 10134 plus or minus 373, treadmill 19624 plus or minus 777, briefcase 21201 plus or minus 798). Isometric exercise alone is much less likely to produce myocardial ischemia than vigorous dynamic exercise. Higher arterial diastolic (coronary perfusion) pressure may retard the development of myocardial ischemia during isometric or combined isometricdynamic exercise in coronary patients.

Angina Pectoris↗