Exercise training modifies nutrient self-selection in rats

Introduced in 1988, cavernous electromyography and its evolution, single potential analysis of cavernous electrical activity (SPACE), seem to be promising diagnostic methods in the evaluation of erectile dysfunction. The aim of our study was to determine the influence of a centrally disturbed autonomic supply on SPACE recordings. SPACE was performed in 35 male patients with complete and 2 with incomplete spinal cord lesions at a cervical or thoracic level. Simultaneous recording was done with concentric needle electrodes in both cavernous bodies with a frequency range of 0.5 to 100 Hz. All patients underwent a full neurological and urological evaluation, including cystometry. The lesion was cervical in 12 patients and thoracic in 22. Three patients underwent sacral deafferentation and bladder pacemaker implantation. One of 12 patients with cervical and 10 of 22 with thoracic lesions reported full rigid reflexogenic erections, while 3 of 12 patients with cervical lesions were not evaluable due to grounding failure. Of these patients 31 were eligible for our study. No patient had an entirely normal SPACE. Four of 9 patients with cervical and 19 of 22 with thoracic lesions had a normal, silent basic electric (less than 5 mu v.) oscillation, while the remainder had a baseline oscillation of up to 100 mu v. Normal potentials were found in 2 of 9 and 10 of 22 patients, respectively. Low frequency, high amplitude potentials were found in 6 of 9 and 21 of 22 patients, respectively, while low frequency, low amplitude potentials occurred in 8 and 8, respectively, and high frequency potentials occurred in 5 and 1, respectively. Our results show that abnormal autonomic input induces abnormal SPACE findings in patients with (presumably) normal cavernous tissue.     

Imagery training and children's prose learning.

Used a pretest-posttest design to examine the effects of passage-illustration training (relative to a reading-practice control procedure) on reading comprehension in 10 3rd and 22 4th graders. Without this imagery training, imagery instructions did not improve performance on either a standardized reading comprehension test or a paraphrase prose recall procedure. After extended training in drawing adequate "comic strips" to illustrate prose passages, performance in a paraphrase recall task improved, but only when explicit imagery instructions were given with the task. The imagery training did not affect the standardized test performance, explicit imagery instructions notwithstanding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exercise training prevents maturation-induced decrease in insulin sensitivity

We examined the effects of exercise training initiated before maturation or after maturation on insulin sensitivity and glucose transporter GLUT-4 content in membrane fractions of skeletal muscle. Female Wistar rats (4 wk of age) were divided into sedentary and exercise-trained groups. At 12 wk of age, a subset of the trained animals (Tr) was killed along with a subset of sedentary controls (Sed). One-half of the remaining sedentary animals remained sedentary (Sed-Sed) while the other half began exercise training (Sed-Tr). The remaining rats in the original trained group continued to train (Tr-Tr). Euglycemic clamp (insulin infusion rate at 6 mU.kg body wt-1. min-1) was performed at 4, 12, and 27 wk. After euglycemic clamp in all animals except the 4-wk-old, hindlimb (gastrocnemius and part of quadriceps) muscles were removed for preparation of membrane fractions. In sedentary rats, glucose infusion rate (GIR) during euglycemic clamp was decreased from 15.9 mg.kg-1.min-1 at 4 wk of age to 9.8 mg.kg-1.min-1 at 12 wk of age and 9.1 mg.kg-1.min-1 at 27 wk of age. In exercise-trained rats, the GIR was not significantly decreased by maturation (at 12 wk) and further aging (at 27 wk). Initiation of exercise after maturation restored the GIR at 27 wk of age to the same levels as these for the corresponding exercise-trained rats. GLUT-4 content in plasma and intracellular membrane fractions of hindlimb muscle obtained just after euglycemic clamp showed the same trend as the results of GIR. These results suggest that exercise training prevented the maturation-induced decrease in insulin sensitivity. Improvement of insulin sensitivity caused by exercise training was attributed, at least in part, to the increase in insulin-sensitive GLUT-4 on the plasma membrane in skeletal muscle.     

Fostering children's revision skills through training in comprehension monitoring.

Elementary school children generally do not revise frequently or skillfully in the classroom. Two studies were conducted to learn if children's ability to revise problematic texts could be facilitated through training in a comprehension monitoring strategy. In the first study, third- and sixth-grade children who were trained on a self-questioning text-evaluation strategy located and revised significantly more target text problems than did control children. The goal of the second study was to compare the effects of prior exposure to problematic texts and self-questioning strategy training. The results showed that a combination of the two approaches was most effective in increasing third graders' revision scores. The results from both studies show that acquiring a strategy for evaluating the comprehensibility of a text can help children make appropriate revisions to improve that text's communicative quality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exercise stress test training in family practice residency programs

EST is a commonly indicated procedure in primary care medicine and as such is well suited for use by family physicians. At present there are few family physicians performing this procedure in their offices. Our survey of US family practice residency directors has shown an interest well above what would be expected for the level of current practice in the community; however, there remains an ambivalence on the need to provide EST training in the curriculum.     

Exercise training in COPD patients: the basic questions

Pulmonary rehabilitation programmes aim at improving exercise capacity, activities of daily living, quality of life and perhaps survival in patients with chronic obstructive pulmonary disease (COPD). Recently, well-designed studies investigated and confirmed the efficacy of comprehensive pulmonary rehabilitation programmes, including exercise training, breathing exercises, optimal medical treatment, psychosocial support and health education. In the present overview, the contribution of exercise training in clinical practice to the demonstrated effects of pulmonary rehabilitation is discussed by means of six basic questions. These include: 1) the significance of exercise training; 2) the optimal intensity for exercise training; 3) prescribing training modalities; 4) the effects of exercise training combined with medication, nutrition or oxygen; 5) how training effects should be maintained; and 6) where the rehabilitation programme should be performed: in-patient, out-patient or homecare? First, exercise training has been proven to be an essential component of pulmonary rehabilitation. Training intensity is of key importance. High-intensity training (>70% maximal workload) is feasible even in patients with more advanced COPD. In addition, the effects on peripheral muscle function and ventilatory adaptations are superior to low-intensity training. There is, however, no consensus on the optimal training modalities. Both walking and cycling improved exercise performance. Since peripheral muscle function has been recognized as an important contributor to exercise performance, specific peripheral muscle training recently gained interest. Improved submaximal exercise performance and increased quality of life were found after muscle training. The optimal training regimen (strength or endurance) and the muscle groups to be trained, remain to be determined. Training of respiratory muscles is recommended in patients with ventilatory limitation during exercise. The additional effects of anabolic-androgenic drugs, oxygen and nutrition are not well-established in COPD patients and need further research. In order to maintain training effects, close attention of the rehabilitation team is required. The continuous training frequency necessary to maintain training effects remains to be defined. At this point in time, out-patient-based programmes show the best results and guarantee the best supervision and a multidisciplinary approach. Future research should focus on the role of homecare programmes to maintain improvements.     

Relationships between dietary fat, body fat, and serum lipid profile in prepubertal children

OBJECTIVE: The purpose of the study was to test the hypothesis that dietary fat components were associated with the serum lipid profile independent of ethnicity, body fat, and fat distribution in prepubertal children. RESEARCH METHODS AND PROCEDURES: Sixty-six children (45 African American and 21 Caucasian), aged from 4 to 10 years, were recruited into the study. Dietary total fat, saturated fat, monounsaturated fat, and polyunsaturated fat were estimated by averaging two 24-hour diet recalls. Fasting serum triacylglycerol, total cholesterol, and high-density lipoprotein cholesterol were analyzed, and low-density lipoprotein cholesterol (LDL-C) was calculated by the method of Friedewald. Body composition and fat distribution were measured by dual energy X-ray absorptiometry and computed tomography. RESULTS: Children in both ethnic groups tended to overreport their dietary intake relative to total energy expenditure by 18%. African American children consumed more energy from total fat (35.3% vs. 31.5%, p<0.05), saturated fat (13.7% vs 12.2%, p<0.05), protein (16.4% vs. 13.2%, p=0.02), and less from carbohydrate (48% vs. 57.1%, p<0.01) than Caucasian children. There was no significant correlation between dietary fat and either serum lipids or body fat indices after adjusting for nonfat energy intake and total lean tissue mass. Total body fat (r=0.32), subcutaneous abdominal adipose tissue (r=0.39), and intra-abdominal adipose tissue (r=0.42) were positively related to serum triacylglycerol; these associations remained significant in a multiple linear regression model in which body fat indices were adjusted for ethnicity, total lean tissue, dietary total fat, and nonfat intake. DISCUSSION: Our results do not support a link between dietary fat and serum lipids; instead, our data suggest that body fat may play a more important role than dietary fat in the course of cardiovascular disease development in prepubertal children.     

Influence of comparison training on children's referential communication.

Assessed whether teaching children to engage in comparison activity improves their referential communication performance. In contrast to previous communication training studies, the training focused on a specifiable unitary skill, employed a teaching procedure with known effectiveness, and controlled for practice and other familiarity effects. Two training experiments with 3rd- and 4th-grade children were conducted. Results from Exp I indicate that 33 trained Ss improved more than 32 control Ss in communication accuracy. Furthermore, gains were maintained at the 1-mo follow-up. Exp II (20 undergraduates; 43 children) examined training effects on message appraisal as well as message production. Results indicate significant training effects on both tasks. Results demonstrate that inadequate comparison processing contributes to children's poor communication performance. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exercise testing as a rehabilitative/training tool

Exercise testing is an exceedingly useful noninvasive method for assessing cardiovascular function not only at rest but also during programmed, supervised physical exercise. Exercise testing has been intensively studied to delineate the cardiovascular response in various disorders [3-5, 15, 19, 22, 23, 26, 32]. Exercise testing as a tool for rehabilitation and for training to perform physical activity is discussed here.     

Exercise training in heart failure: inpatient and outpatient considerations

Highly reactive oxygen species that are formed during normal metabolism and under conditions of oxidative stress are able to oxidize proteins or convert lipid and carbohydrate derivatives to compounds that react with functional groups on proteins. Among other changes, these ROS-mediated reactions lead to the formation of protein carbonyl derivatives, which serves as a marker of ROS-mediated protein damage. On the basis of this marker, it is established that oxidatively damaged protein is associated with aging and some diseases. The accumulation of oxidatively damaged protein reflects the balance among a myriad of factors that govern the rates of ROS generation and the rate at which damaged protein is degraded. Peroxynitrite, which is formed under normal physiological conditions, is able to oxidize methionine residues in proteins and to nitrate tyrosine residues; however, its ability to do so is dependent on the availability of CO2, which stimulates the nitration of tyrosine residues but inhibits the oxidation of methionine residues. Nitration of tyrosine residues may contribute to peroxynitrite toxicity, as nitration precludes the phosphorylation or nucleotidylation of tyrosine residues and thereby seriously compromises one of the most important mechanisms of cellular regulation and signal transduction.     

Sex differences in children's response to training on a visual-spatial test.

In a study with 133 children in Grades 1, 3, and 5, a brief training procedure designed to improve performance on the Children's Embedded Figures Test, a test of visual ability, resulted in significant improvement for girls but not for boys. No sex difference was observed among children receiving this training. The implications for theories of sex differences in visual–spatial ability are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exercise limitations and training for patients with cystic fibrosis

Exercise has much to offer to cystic fibrosis patients. Overcoming the limits of decreased pulmonary function by increasing fitness has a considerable potential to improve patients' quality of life; decreased breathlessness allows greater mobility and participation with peers in social and sporting activities, improves confidence and self-esteem and creates a greater pleasure in life for the individual patient. There are also immediate therapeutic gains and potentially long-term gains with improved survival. Above all, cystic fibrosis patients enjoy and prefer exercise as a therapeutic option to most other forms of therapy.     

Exercise training restores decreased cellular immune functions in obese Zucker rats

This study investigated whether exercise training had a beneficial effect on the decreased mitogen response and improved a decreased expression of glucose transporter 1 (GLUT-1) in splenocytes from obese Zucker rats. Experimental groups were lean and sedentary and exercise-trained obese Zucker rats. Exercise training, running on a motor-driven treadmill for 5 days/wk for 40 wk, did not induce a significant decrease in body weight in obese Zucker rats. The plasma insulin concentration, showing a significant increase compared with lean Zucker rats, was unaffected by exercise training. However, the plasma triglyceride concentration in obese Zucker rats was significantly depressed by exercise training, whereas it was still higher than that in lean Zucker rats. In addition, natural killer cell activity and concanavalin A-induced mitogenesis of splenic lymphocytes of obese Zucker rats were significantly restored. In these splenic lymphocytes, glucose uptake was significantly lower compared with that in lean Zucker rats, which was also improved by exercise training. Although the expression of GLUT-1, the major glucose transporter in immune cells, was depressed in splenic lymphocytes of obese Zucker rats, exercise training induced a significant improvement. These results suggest that exercise training has a beneficial effect on the decreased cellular immune functions in obese Zucker rats, which is associated, in part, with the improvement in GLUT-1 expression.     

Exercise training alters endothelium-dependent vasoreactivity of rat abdominal aorta

We tested the hypothesis that adaptations in peripheral arterial vasoreactivity are induced by exercise training. Male rats were trained to run on a treadmill at 30 m/min (15 degrees incline) for 1 h/day 5 days/wk for 10-12 wk. Efficacy was indicated by a 51% increase (P < 0.05) in citrate synthase activity in soleus muscle of exercise-trained (ET) rats compared with that of sedentary (SED) control rats. Responses to vasoactive compounds were examined in vitro using rings of abdominal aorta. Maximal isometric contractile tension evoked by KCl, norepinephrine (NE), and phenylephrine were not different between groups; sensitivity to phenylephrine was also not different between groups. However, sensitivity was lower for both KCl and NE in vessels from ET animals. Endothelium removal did not influence KCl sensitivity but did abolish the difference in NE sensitivity of vessel segments between ET and SED animals. Maximal vasodilator responses induced by acetylcholine (ACh; NE or prostaglandin F2 alpha preconstriction) were greater in vessel rings from ET rats. However, dilatory responses by sodium nitroprusside (NE or prostaglandin F2 alpha preconstriction) and forskolin (NE preconstriction) were not different between groups, indicating that the augmented ACh-induced dilatory response resulted from an adaptation of the endothelium. Blockade of nitric oxide synthase activity diminished ACh-induced vasodilation by 79 and 100% in SED and ET rats, respectively. These results indicate that training alters vasomotor function in rat abdominal aortas through adaptations of both endothelium and smooth muscle.     

Exercise training reduces myocardial lipid peroxidation following short-term ischemia-reperfusion

PURPOSE: The purpose of these experiments was to test the hypothesis that endurance exercise training will reduce myocardial lipid peroxidation following short-term ischemia and reperfusion (I-R). METHODS: Female Sprague-Dawley rats (4 months old) were randomly assigned to either a sedentary control group (N = 13) or to an exercise training group (N = 13). The exercise trained animals ran 4 d.wk-1 (90 min.d-1) at approximately 75% V02max. Following a 10-wk training program, animals were anesthetized, mechanically ventilated, and the chest was opened by thoracotomy. Coronary occlusion was achieved by a ligature around the left coronary artery; occlusion was maintained for 5 min followed by a 10-min period of reperfusion. RESULTS: Although training did not alter (P > 0.05) myocardial activities of antioxidant enzymes (superoxide dismutase and glutathione peroxidase), training was associated with significant increase (P > 0.05) in heat shock protein (HSP72) in the left ventricle. Compared with controls, trained animals exhibited significantly lower levels (P < 0.05) of myocardial lipid peroxidation following I-R. CONCLUSION: These data support the hypothesis that exercise training provides protection against myocardial lipid peroxidation induced by short-term I-R in vivo.     

Renal alterations induced by Cerastes cerastes cerastes venom

The purpose of the present study was to determine the structural and functional alterations in the kidneys of rats experimentally envenomated with the viper Cerastes cerastes cerastes. The effects of a single i.p. sub-LD50 (0.73 mg Kg-1) for 24 hr and 7 consecutive doses (0.42 mg Kg-1; daily injection) on the kidneys of rats were studied. Histological examination of the kidneys in envenomated rats revealed the presence of atrophied glomeruli, cloudy materials within the proximal and distal convoluted tubules, atrophy and hypertrophy of quite a large number of tubular nuclei and mesangial proliferation. Hemorrhagic areas, dilated thrombosed vessels, fibrosis, and mitotic indices were also among the histopathological alterations in the renal cortex of the venom-injected animal groups. Electron microscopical findings revealed the presence of cell debris and electron dense materials within the lumen of the distal and proximal convoluted tubules. The cell lining of the proximal convoluted tubules underwent variable degrees of degeneration, and most of their intracellular organelles were deteriorated. The glomeruli contained quite large areas of mesangial matrix, and the lumen of most of their blood capillaries enclosed a moderately electron dense matrix. The cells of the endothelial lining of these capillaries were hypertrophied, and most of them lost their integrity and diffused with the surrounding matrix of the capillary lumen. Several leukocytic aggregates were observed in the intertubular spaces and blood capillaries. In addition, the erythrocytes of most of these capillaries displayed different patterns of electron density.     

Echocardiographic changes and alterations in lipid profile in cases of subclinical and overt hypothyroidism

Forty four patients (22 of overt hypothyroidism and 22 of subclinical hypothyroidism) and 11 controls underwent lipid profile evaluation and two dimensional echocardiography. Amongst the various parameters evaluated, mean Interventricular Septal (IVS) dimensions were significantly (p < 0.005) raised in overt hypothyroidism [IVS: end diastolic (ED) = 0.973 +/- 0.223 cm.; end systolic (ES) = 1.300 +/- 0.240 cm.] with respect to control group [IVS : ED = 0.747 +/- 0.118 cm.; ES = 1.073 +/- 0.173 cm.]. Mean Left Ventricular Posterior Wall (LVPW) thickness was also significantly (p < 0.005) raised in overt hypothyroidism [LVPW : ED = 0.944 +/- 0.200 cm.; ES = 1.350 +/- 0.243 cm.] in comparison with control group [LVPW : ED = 0.779 +/- 0.091 cm.; ES = 1.176 +/- 0.128 cm.]. Evidence of diastolic dysfunction was present in both subclinical (n = 2) and overt hypothyroidism (n = 6) while pericardial effusion was seen only in overt hypothyroidism (n = 10). Mean Serum cholesterol was significantly raised in both subclinical (192.13 +/- 47.40 mg%) (p < 0.05) and overt hypothyroidism (231.27 +/- 68.30 mg%) (p < 0.005) with respect to control group (157.63 +/- 37.69 mg%). In overt hypothyroid patients mean serum Triglyceride (235.59 +/- 137.53 mg%) (p < 0.05), LDL (126.09 +/- 54.99 mg%) (p < 0.05) and Apo-B (0.698 +/- 0.354 g/L) (p < 0.05) levels were significantly higher as compared to control group (serum triglyceride 165.45 +/- 49.15 mg%, LDL 88.72 +/- 38.75 mg%, Apo-B 0.474 +/- 0.176 g/L.     

Exercise induced bronchial lability in normal men and women--a comparison

Normal male (n = 29) and female (n = 39) medical students with a mean age of 19.2 years who were nonsmokers, with no personal history of allergy were studied. The bronchial lability was assessed from peak expiratory flows and forced expiratory spirograms taken before, during and upto 45 minutes after a standard exercise using the Harvard steps. Women had a significantly lower (P < .001) resting FVC, FEV1, FEF 25-75% and PEF as compared to men. Although the exercise lability index was not significantly different in men and women, the latter showed a greater percent increase (P < .02) and a lesser percent decrease (P < .02) of PEF during and after the exercise respectively. They also showed a significantly (P < .005) faster recovery to normal. These results suggest that airway dynamics may be better in women than in men. This could account for the lower incidence and morbidity from respiratory allergic disease seen in women as compared to men.     

Lipoprotein profile in canine pancreatitis induced with oleic acid

In the treatment of children with brain tumors, balancing the efficacy of treatment against commonly observed side effects is difficult because of a lack of quantitative measures of brain damage that can be correlated with the intensity of treatment. We quantitatively assessed volumes of brain parenchyma on magnetic resonance (MR) images using a hybrid combination of the Kohonen self-organizing map for segmentation and a multilayer backpropagation neural network for tissue classification. Initially, we analyzed the relationship between volumetric differences and radiologists' grading of atrophy in 80 subjects. This investigation revealed that brain parenchyma and white matter volumes significantly decreased as atrophy increased, whereas gray matter volumes had no relationship with atrophy. Next, we compared 37 medulloblastoma patients treated with surgery, irradiation, and chemotherapy to 19 patients treated with surgery and irradiation alone. This study demonstrated that, in these patients, chemotherapy had no significant effect on brain parenchyma, white matter, or gray matter volumes. We then investigated volumetric differences due to cranial irradiation in 15 medulloblastoma patients treated with surgery and radiation therapy, and compared these with a group of 15 age-matched patients with low-grade astrocytoma treated with surgery alone. With a minimum follow-up of one year after irradiation, all radiation-treated patients demonstrated significantly reduced white matter volumes, whereas gray matter volumes were relatively unchanged compared with those of age-matched patients treated with surgery alone. These results indicate that reductions in cerebral white matter: 1) are correlated significantly with atrophy; 2) are not related to chemotherapy; and 3) are correlated significantly with irradiation. This hybrid neural network analysis of subtle brain volume differences with magnetic resonance may constitute a direct measure of treatment-induced brain damage.     

Exercise before puberty may confer residual benefits in bone density in adulthood: studies in active prepubertal and retired female gymnasts

In this paper, we report on the development of a technique for the kinetic characterization of the metabolic reactions of liver cells in adhesion culture. The technique is based on the use of a continuous-flow bioreactor which is designed and operated in such a way as to ensure a uniform distribution of metabolite at the cell site: hence, the metabolite concentration at the surface of cells cultured in adhesion at the bottom of the bioreactor equals that in the stream leaving the bioreactor. Under steady conditions, the rate of a given cell reaction is directly estimated from the metabolite concentration difference in the streams entering and leaving the bioreactor and can be correctly related to the actual concentration at the cell surface. Such a technique was used for a preliminary investigation of the kinetics of ammonia elimination, urea synthesis, and phenolsulfonphthalein (PSP) elimination by primary rat hepatocytes cultured in adhesion on collagen, with respect to ammonia and PSP concentration, respectively. The rate at which the hepatocytes eliminated ammonia increased with increasing ammonia concentrations according to a Michaelis-Menten kinetics. The hepatocytes synthesized urea also in the absence of ammonia in the medium: as ammonia concentration increased, the cells synthesized urea at a rate that increased according to a saturation kinetics. In the concentration range investigated, the hepatocytes eliminated PSP at a rate that increased linearly with the actual PSP concentration in the medium. Such kinetic information can be coupled to the mechanism of metabolite transport in a hybrid liver support device to yield an effective device design for the treatment of acute liver failure.