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Biomedical subjects

J Keul

Publications and source records attributed to J Keul.

At least 73 records · Page 4Linked to original sources
PubMed1997

Correlation between physical performance and fatigue in cancer patients.

BACKGROUND: Fatigue and a reduction in physical ability are common and often severe problems of cancer patients regardless of disease stage and modality of treatment. However, while physical performance can be assessed objectively with laboratory tests, fatigue is a subjective phenomenon whose perception is influenced by past experience and expectations for the future. PATIENTS AND METHODS: To evaluate the correlation between fatigue and physical impairment, we assessed maximal physical performance with a treadmill test, and mental state with two questionnaires, the Profile of Mood States (POMS) and the Symptom Check List (SCL-90-R), in a successive series of 78 cancer patients with solid tumors or hematological malignancies. RESULTS: A weak association between fatigue and maximal physical performance was found (r = -0.30; P < 0.01). However, intensity of fatigue showed a strong correlation with several indicators of psychological distress such as depression (r = 0.68), somatization (r = 0.64) and anxiety (r = 0.63; P for all < 0.001). Furthermore, patients with lower levels of physical performance had significantly higher scores for depression (P = 0.005), somatization (P = 0.03) and anxiety (P = 0.08), and significantly lower scores for vigor (P = 0.05) than their counterparts whose physical performance was higher. CONCLUSIONS: We conclude that fatigue in cancer patients may be related to mood disturbance but appears to be independent of physical performance. Moreover, low physical performance can be viewed as an independent predictor of mental distress in cancer patients.

Adolescent↗
PubMed1997

Effect of exhaustive exercise stress on the cytokine response.

Fifteen athletes were investigated 24 h before, 1 h after, and 20 h after an exhaustive exercise stress test (mean duration 68 min). Testing for cytokines was done in serum, urine, and the supernatants of whole blood cell cultures, which were stimulated with lipopolysaccharide (LPS), concanavalin A (Con A), or phythaemagglutinin (PHA). Elevated levels of interleukin 6 (IL-6) and soluble IL-2 receptor (sIL-2R) were found 1 h after the run in both serum and urine samples. TNF-alpha in serum was also increased, whereas IL-2 in urine was decreased after the exercise. All other testings in serum and urine (including IFN-gamma) gave borderline or negative results. In cell cultures, the LPS-induced release of the inflammatory cytokines TNF-alpha, IL-1, and IL-6 was suppressed 1 h after exercise. Also, the Con-A-induced and LPS-induced release of IFN-gamma, and the PHA-induced release of IL-2 were suppressed 1 h after exercise. In contrast, Con-A-induced release of IL-2 was mildly increased after the run. We conclude that exercise of the intensity and duration described here causes an activation of the immune system, which is immediately counter-regulated. Twenty hours after the exercise, most of the observed changes were back to pre-exercise levels, indicating only a short duration for this suppressive counter-regulation.

Adult↗
PubMed1997

Muscle-specific creatine kinase gene polymorphisms in elite endurance athletes and sedentary controls.

The purpose of this study was to investigate the association between elite endurance athlete (EEA) status and two restriction fragment length polymorphisms (RFLPs) at the muscle-specific creatine kinase (CKMM) gene locus. Genomic DNA was extracted from white blood cells or lymphoblastoid cell lines of 124 unrelated Caucasian male EEA (VO2max > 73 mL.kg-1.min-1) and 115 unrelated Caucasian sedentary male controls (SCON). The genetic polymorphism at the CKMM locus was detected by the polymerase chain reaction and DNA digestion with the NcoI and TaqI restriction endonucleases. The allelic frequencies for the NcoI and TaqI RFLPs were not different (P > 0.05) between EEA and SCON subjects. The three expected genotypes for CKMM-NcoI (1170/1170 bp, 1170/985 + 185 bp, and 985 + 185/985 + 185 bp) and CKMM-TaqI (1170/1170 bp, 1170/1020 + 150 bp, and 1020 + 50/1020 + 150 bp) were observed in the EEA and SCON groups. These genotype frequencies were in Hardy-Weinberg equilibrium, but they were not significantly (P > 0.05) different between the EEA and SCON. A strong (P < 0.001) linkage disequilibrium was detected among the NcoI and TaqI RFLPs in both EEA and SCON. These findings indicate that the skeletal muscle CK-NcoI and CK-TaqI gene polymorphisms are not associated with the elite endurance athlete status.

Adult↗
PubMed1997

Highland mountain hiking and coronary artery disease: exercise tolerance and effects on left ventricular function.

Physical exercise has become a well-established concept in the secondary prevention of coronary artery disease. We investigated the exercise requirements of extensive highland mountain hiking (8.7 km, 470 m to 1220 m over sea level, average incline 8.5%, mean walking velocity < 3 km x h-1) in 11 regularly exercising male patients with history of MI and stable coronary artery disease (CAD; mean age +/- SD:61.0 +/- 3.9 yr) and 9 age-matched male healthy controls (CO; mean age +/- SD:61.2 +/- 5.0 yr). All subjects underwent continuous ECG monitoring; arterial blood pressure and blood lactate concentrations were measured several times during mountain hiking. Before and after exercise, cardiac dimensions and functions were assessed by two-dimensional echocardiography and Doppler echocardiography. The mean exercise levels for heart rate and blood lactate were compared with the corresponding data of a multistage upright cycle ergometry. Clinical manifestations of coronary insufficiency, left ventricular myocardial dysfunction, or cardiac arrhythmias > Lown IIIb were not observed in any case. No significant differences in left atrial and left ventricular dimensions and no changes in systolic left ventricular function compared with the preexercise values were found after the mountain hike tour. Doppler echocardiography demonstrated significant changes in diastolic left ventricular function in CAD, but not in CO. The peak exercise intensity during mountain hiking was equivalent to a workload of 100-125 W (1.25-1.5 W x kg-1 body weight) in a multistage upright cycle ergometry. Extensive highland mountain hiking may be a low risk alternative within the outpatient rehabilitation program for secondary prevention of CAD for MI patients with a cycle ergometric exercise tolerance > 1.5 W x kg-1 body weight.

Aged↗
PubMed1997

Essential fatty acids, immune function, and exercise.

The immunologic response to exercise comprises numerous alterations within the immune system, but how these processes are regulated is still largely unknown. Exercise-related immunological changes include signs of inflammation, such as release of inflammatory mediators, activation of various white blood cell lines and complement, and induction of acute phase proteins. Nevertheless, signs of immunosuppression, such as decreased T and B cell function or impaired cytotoxic or phagocytic activity, can also be observed. Some data suggest that essential fatty acids help regulate inflammatory processes, modulating both cytokine release and the acute phase response. Positive effects of changing dietary essential fatty acids have been demonstrated in chronic inflammatory diseases. In contrast, little is known about the contribution of fatty acids to the exercise-induced immunologic reaction. Essential fatty acids may determine alterations within the immune system following exercise. Therefore, future studies are necessary to evaluate the influence of the fatty acid composition on the inflammatory or immunosuppressive component following heavy exertion.

Acute-Phase Reaction↗
PubMed1997

Crystallization and preliminary X-ray diffraction data of two different human low-density lipoprotein (LDL) subfractions.

Human LDL subfractions LDL-2 (d = 1.031-1.034 g/ml) and LDL-5 (d = 1.040-1.044 g/ml) were crystallized in two different crystal forms by using polyethylene glycol as a precipitant. Both fractions were from one donor. Crystals of LDL-5 were yellow, hexagonal, and showed no dichroism. Crystals of LDL-2 were of the same color, had a rodlike shape with notches at both ends, and were highly dichroitic. LDL-2 crystals diffracted to a resolution of 29 A by using synchrotron radiation. Indexing in P1 resulted in preliminary parameters for the reduced cell of a = 171 A, b = 438 A, c = 519 A, alpha = 102 degrees, beta = 99 degrees, gamma = 91. These dimensions are consistent with the size of LDL particles. Using Fourier transform infrared spectroscopy (FTIR) and agarose gel electrophoresis, we could further confirm that the crystals consist of LDL. The FTIR spectrum showed bands characteristic for lipids and protein. Dissolved crystals exhibited a mobility similar to native LDL in agarose gels and could be stained with anti-human apolipoprotein B (apoB).

Crystallization↗
PubMed1997

[Physical training of patients with sleep apnea].

PURPOSE: It is a common question of sleep apnoea patients in the sleep lab whether they stand a chance to decrease the symptoms and severity of their disease by physical exercise. As far as we know, there is no data about this specific question until now, even though this has been subject to speculation. A few studies, however, report on an improvement of the respiratory drive (and chemoreceptor sensitivity) after physical exercise in athletes. The aim of this study was to prove whether physical exercise in sleep apnoea patients could improve the symptoms of their disease in an open trial. METHODS: 11 Patients with mild to severe sleep apnoea syndrome (1 f, 10 m, mean age 53.8x) took part in a 6-month period of physical exercise twice a week 2 h each time under the instructions of physical therapists. Before and after the 6mo period a full PSG without CPAP or BIPAP, a bicycle exercise test with lactate profile, echocardiography, blood test, and body weight and body height measurement was performed. Statistical analysis was done using Wilcoxon ranked test and multiple regression analysis. RESULTS: There was no significant bodyweight reduction in all patients after the 6mo period of physical training, no significant difference in either basal SaO2 nor mean SaO2 and no significant improvement in physical status by the p at 4 mmol lactate on the lactate profile. Echocardiographic changes were not found; there was no significant change in the blood pressure profiles during the bicycle test. No cardiopulmonary problems including exercise-induced high blood pressure were reported during the training period. There was, however, a significant decrease of the RDI (p < 0.05), but no significant change in the REM-sleep % of total sleep time (TST) and the TST itself. CONCLUSIONS: There was an improvement of the sleep apnoea syndrome correlated to a decrease of the RDI in the studied patient population due to a possible increase in the respiratory drive or a stabilised muscle tone ine the upper airways after physical exercise, as reported by other authors, because weight reduction could not be the reason in our patients. Our trial showed that the exercise does not increase the severity of symptoms of sleep apnoea by changing the REM/non REM ratio or for any other reasons. A physical training programme for sleep apnoea patients as an additional treatment should therefore be considered.

Adult↗
PubMed1997

[Reducing cholesterol in cardiovascular rehabilitation--exercise versus drug therapy].

Prospective epidemiological studies have proven a close link between the improvement of the lipoprotein profile and reduction of coronary heart mortality in coronary heart disease (CHD) patients. Both, regular physical activity and pharmacological intervention are capable of improving the lipoprotein profile and may independently reduce coronary stenoses and cardiac events in CHD patients. Because of the multifactorial genesis of atherosclerosis, regular physical activity is of major importance for cardiac rehabilitation and improvements of other risk factors besides the lipoprotein profile e.g. rheology, hypercoagulability, hypertension, peripheral insulin resistance and oxidative status may be expected. The combination of life-style changes e.g. physical activity, diet and smoking cessation together with pharmacological intervention, if risk factors remain high, seems to be the best therapy for patients with CHD. A sole pharmacological intervention seems to be insufficient.

Anticholesteremic Agents↗
PubMed1996

[Coronary circulation and metabolic function in endurance trained paraplegics].

OBJECTIVE: To determine the effect of physical activity on pulmonary, cardiovascular and metabolic activity in paraplegics. PATIENTS AND METHODS: Eight male paraplegics (average age 35.7 [range 25-47] years) had been selected from a pool of training members of the German Sport Union for the Disabled. They performed graded arm crank training for 8.3 +/- 3.1 h/week. Left ventricular volume (LVV), stroke volume (SV), wall thickness (WT), heart rate (HR) as well as serum lactate concentration were measured after different levels of the graded exercise. Results were compared with those obtained in 11 male sport students (average age 26.4 [23-30] years), who had similarly trained for 5.6 +/- 1.3 h/week. RESULTS: The paraplegics had a significantly smaller LVV than the controls (771 +/- 84 ml vs 976 +/- 84 ml) and smaller SV (83 +/- 13 ml vs 104 +/- 11ml), with comparable WT. Paraplegics achieved significantly lower maximal exercise (145 +/- 23.7 vs 160 +/- 28.2) and maximal HR (177 +/- 12 vs 170 +/- 9) were not significantly different at the various exercise steps. CONCLUSION: Paraplegia decreases cardiac dimensions and function. Long-term physical exercise achieves results comparable with those of untrained but not of trained healthy controls. Physically active paraplegics showed physiological cardiovascular and metabolic reactions to exercise.

Adult↗
PubMed1996

Unaccustomed high-mileage vs intensity training-related changes in performance and serum amino acid levels.

To test the overtraining-related "imbalanced amino acid hypothesis" (19), the influence of an unaccustomed average 103 %.4 wk-1 increase in training mileage (ITV) on performance and on serum levels of individual amino acids (AAs) was examined in distance runners and controlled by an unaccustomed average 152%.4 wk-1 increase in tempo-pace and interval runs (ITI). Two mmol.l-1 lactate performance (2 LP) increased, 4 LP stagnated and total running distance (TD) decreased in the incremental test during ITV--which may indicate an ITV-dependent overtraining--in contrast to an ITI-related increase in 2 LP, 4 LP and TD. The summed serum AAs decreased in ITV (2744 +/- 534 vs 2933 +/- 663 umol.l-1; p < 0.05) in contrast to an ITI-related increase (3541 +/- 657 vs 3252 +/- 885 umol.l-1; p < 0.05) with an average 29% higher final summed AAs concentration during ITI (p < 0.05). During ITV 12 individual AAs decreased by 6-17%, 8 remained constant and 3 increased (Cys, Met, fTrp) by 6-19%, as opposed to an ITI-related increase in 16 AA by 6-55%. The observed ITV-related changes in serum AAs profile were smaller than after completing contests as a marathon, a 100 km-run or an ultra-triathlon. It may be concluded that the observed small changes in AAs profile or AAA/BCAA and AA/LNAA ratios only represent an epiphenomenon without recognizable influence on incremental test performance, since increases in fTrp/LNAA ratios (+28% in ITV vs +45% in ITI) were found to be related both to performance impairment (ITV) and improvement (ITI).

Adult↗
PubMed1996

Structural and functional adaptations of the cardiovascular system by training.

Muscular training induces structural and functional adaptations within the cardiovascular system which vary according to type, intensity and duration of muscular exertion. Dynamic muscular training for more than 5 h a week involving more than 1/6th of the skeletal muscle mass causes an increase in parasympathetic tone and an eccentric myocardial hypertrophy. The dimensions of all cardiac chambers enlarge up to 20% and the cardiac muscle mass may increase by 70%-80%. Static muscular training does not induce any change in the parasympathetic heart regulation, nor does it lead to any disproportional increase in cardiac muscle mass relative to skeletal muscle mass. However, a tendency towards a concentric myocardial hypertrophy can be observed. The effects of regular muscular training on the arteries are the subject of current scientific investigation. To explain the acute and chronic adaptations of the arterial vasculature to exercise, a "shear stress" hypothesis has been proposed. During dynamic muscular exercise the regional arterial blood flow is enhanced. This leads to an acute increase in intraluminal shear forces, which stimulates the vascular endothelium with a reactive flow-dependent regional vasodilation mediated by endothelial-derived relaxing factors (EDRF, EDNO). Chronic enhancement of shear forces induces endothelial cell-mediated alterations in gene expression (endothelin, growth factors, regulators of fibrinolysis) and chronic structural adaptations of the vascular wall (cytoskeletal redistribution, cell shape change). Recent duplex sonographic studies in humans have revealed a significant lumen increase of muscular type arteries induced by dynamic, predominantly aerobic muscular training, but not by static muscular training. These structural adaptations are confined to those arteries supplying exercising muscle groups, whereas functional adaptations with an improvement of regional compliance are found in all arteries.

Adaptation, Physiological↗
PubMed1996

Assessment of left ventricular dimensions and functions in athletes and sedentary subjects at rest and during exercise using echocardiography, Doppler sonography and radionuclide ventriculography.

During recent years the echocardiographic procedure has been extended regarding the evaluation of left ventricular myocardial function during exertion. During exercise echocardiography, body position is important for the correct assessment of cardiac dimensions and function, particularly for the measurement of the cross-sectional diameters of the left ventricle and diastolic myocardial function. Reliable parameters of left ventricular function during exercise are left ventricular ejection fraction and endsystolic left ventricular volume, but not enddiastolic left ventricular volume. The increase of left ventricular ejection fraction during exercise up to submaximal exertion primarily results in a reduction of endsystolic left ventricular volume and partially in a simultaneous increase of enddiastolic left ventricular volume. In several cross-sectional studies comparing untrained and endurance trained hearts a higher diastolic filling rate, a higher maximal blood flow velocity of early diastolic passive left ventricular filling and a higher early diastolic filling fraction at rest and during exercise could be proved in endurance trained hearts. These training-induced adaptations of diastolic left ventricular function have been confirmed by a longitudinal study with primarily untrained young and older healthy subjects performing a heart rate controlled endurance training programme. Stress echocardiographic and simultaneous spiroergometric investigations indicated a correlation between the diastolic left ventricular function and the maximal oxygen uptake. The currently available data on the sensitivity, the intraobserver and interobserver variability of Doppler echocardiography have shown that this non-invasive procedure is valid for the evaluation of the systolic and the diastolic myocardial function at rest and during exercise. However, the procedure is limited to patients where the ultrasonographic assessment of cardiac structures is not considerably restricted. Furthermore, the reliability of stress Doppler echocardiography is dependent considerably on the practical skills of the observer.

Adaptation, Physiological↗
PubMed1996

Lipoprotein(a) in endurance athletes, power athletes, and sedentary controls.

Elevated concentrations of lipoprotein(a) [Lp(a)] have been shown to be an independent risk factor for atherosclerotic disease. Physical activity and physical fitness have been shown to improve lipoprotein metabolism and reduce the risk of coronary artery disease. Studies on the influence of physical activity and physical fitness on Lp(a) levels including a large number of endurance as well as power athletes have not been performed before. Therefore, we determined parameters of physical fitness (maximal oxygen consumption), physical activity, and lipoproteins in 105 endurance athletes, 57 power athletes, and 87 sedentary young men. As expected, we found that endurance athletes with a good physical fitness had significantly higher concentrations of high-density lipoprotein cholesterol than power athletes and sedentary controls. Regarding mean Lp(a) levels (rocket immunoelectrophoresis), however, there were no significant differences between endurance athletes, power athletes, and sedentary controls. Even when including only those with Lp(a) values > 10 mg.dl-1, no differences were observed between the groups. These findings indicate that intensive training over years and good aerobic fitness improve the ratio of low-density lipoprotein to high-density lipoprotein cholesterol but have no or only minor effects on Lp(a) concentrations.

Adult↗
PubMed1996

Effect of physical exercise and vitamin C on absorption of ferric sodium citrate.

The effect of physical exercise and vitamin C on iron absorption after oral iron administration was investigated. Eight healthy male subjects without iron deficiency were studied after administration of 100 mg ferric sodium citrate complex, 100 mg ferric sodium citrate complex with 200 mg ascorbic acid, and without iron intake, both under resting conditions and after a 1-h bicycle ergometer test at moderate exercise. Serum concentrations for iron, transferrin, and ferritin were measured before and 30 min, and 1, 2, and 4 h after each administration. Under resting conditions administration of 100 mg ferric sodium citrate led to a significant increase in serum iron concentrations. When ferric sodium citrate was administered with vitamin C, iron values increased significantly further. Ingestion of iron together with physical exercise resulted in a higher serum iron concentration than under resting conditions. The maximum increase, reached after 4 h, was 48.2% with exercise and 8.3% without. In combination with exercise, the addition of 200 mg vitamin C did not further increase serum iron concentration. In conclusion, 1 h of moderate exercise enhanced the rate of iron absorption. Under resting conditions the combination of ferric sodium citrate with vitamin C led to significantly increased postabsorption serum iron concentrations compared with iron administration without vitamin C.

Adult↗
PubMed1996

Association between serum fibrinogen concentrations and HDL and LDL subfraction phenotypes in healthy men.

Hyperfibrinogenemia and a dyslipoproteinemia characterized by reduced HDL2 cholesterol and elevated levels of small, dense LDL particles are risk factors for coronary artery disease. However, the relationship between fibrinogen and lipoproteins, in particular LDL subfractions, is uncertain. We therefore measured serum fibrinogen levels and serum concentrations of cholesterol and apolipoproteins of VLDL, IDL, six LDL, and two HDL subfractions by using the technique of density-gradient ultracentrifugation in 132 nonsmoking men without evidence of coronary artery disease or infection. Dividing the individuals into quartiles according to their fibrinogen values showed that men within the highest fibrinogen quartile (fibrinogen 2.90 to 4.34 g/L) had significantly higher concentrations of small, dense LDL (d > 1.044 g/mL) apolipoprotein B and cholesterol and lower concentrations of HDL2 cholesterol than men within the lower fibrinogen quartiles (fibrinogen < 2.55 g/L). Multivariate regression analysis revealed that the association between fibrinogen and small, dense LDL particles was independent of serum triglycerides, cholesterol, body mass index, and age. In contrast, the relationship between fibrinogen and HDL2 cholesterol was primarily influenced by triglycerides and cholesterol and not independently influenced by fibrinogen. There were no significant differences between the quartiles in terms of insulin, glucose, insulin resistance, free fatty acids, lipoprotein(a), and blood pressure. This study showed that fibrinogen is associated with the expression of a more atherogenic LDL subfraction phenotype independent of body mass index, age, other serum lipids, and insulin resistance in a healthy male nonsmoking population. The reason for this association is uncertain. These findings reinforce the evidence that fibrinogen should be determined when assessing coronary risk.

Aging↗
PubMed1996

An aerobic exercise program for patients with haematological malignancies after bone marrow transplantation.

We describe the effects of an aerobic exercise program designed to improve the physical performance of patients undergoing bone marrow transplantation. Twenty patients entered the rehabilitation program, consisting of walking on a treadmill, and carried it out for 6 weeks. Patients started the training program 30 +/- 6 days (range 18-42) post-BMT. By the end of the program we observed a significant improvement in maximal physical performance and maximum walking distance, and a significant lowering of the heart rate with equivalent workloads (P for all significances < 0.001). All participants of the program reached a peak performance (calculated in metabolic equivalents, METs) more than sufficient for carrying out all basic activities of daily living. These results contrast with literature reports indicating that spontaneous recovery of physical functioning after BMT can take many months and that about 30% of patients experience long-lasting impairment of physical performance. We conclude that that fatigue and loss of physical performance in patients undergoing BMT can be corrected with adequate rehabilitative measures.

Adult↗