Mediators of physical exercise for improvement in cancer survivors' quality of life.

OBJECTIVE: Mediating mechanisms of a 12-week group-based exercise intervention on cancer survivors' quality of life (QoL) were examined to inform future exercise intervention development. METHODS: Two hundred nine cancer survivors ≥ 3 months posttreatment (57% breast cancer) aged 49.5 (± 10.4) years were assigned to physical exercise (n = 147) or wait-list control (n = 62). QoL, fatigue, emotional distress, physical activity, general self-efficacy and mastery were assessed at baseline and post-intervention using questionnaires. Path analysis was conducted using Mplus to explore whether improved physical activity, general self-efficacy and mastery mediated the effects of exercise on fatigue and distress and consequently QoL. RESULTS: The intervention was associated with increased physical activity (ß = 0.46, 95% confidence interval (CI) = 0.14;0.59), general self-efficacy (ß = 2.41, 95%CI = 0.35;4.73), and mastery (ß = 1.75, 95%CI = 0.36;2.78). Further, the intervention had both a direct effect on fatigue (ß = -1.09, 95%CI = -2.12;0.01), and an indirect effect (ß = -0.54, 95%CI = -1.00;-0.21) via physical activity (ß = -0.29, 95%CI = -0.64;-0.07) and general self-efficacy (ß = -0.25, 95%CI = -0.61;-0.05). The intervention had a borderline significant direct effect on reduced distress (ß = -1.32, 95%CI = -2.68;0.11), and a significant indirect effect via increased general self-efficacy and mastery (ß = -1.06, 95%CI = -1.89;-0.38). Reductions in fatigue (ß = -1.33, 95%CI =-1.85;-0.83) and distress (ß = -0.86, 95%CI = -1.25;-0.52) were associated with improved QoL. Further, increased physical activity was directly associated with improved QoL (ß = 3.37, 95%CI = 1.01;5.54). CONCLUSION: The beneficial effect of group-based physical exercise on QoL was mediated by increased physical activity, general self-efficacy and mastery, and subsequent reductions in fatigue and distress. In addition to physical activity, future interventions should target self-efficacy and mastery. This may lead to reduced distress and fatigue, and consequently improved QoL of cancer survivors.

Perceived competence in children and adolescents with haemophilia: an explorative study.

With the introduction of prophylaxis, restricting children with haemophilia to participate in physical activities was no longer necessary. Subsequently, many studies report on improved physical functioning in children and adolescents with haemophilia. However, little is known about psychological aspects such as perceived competence and impact of disease. Therefore, the aims of this study were to explore: (i) perceived competence, (ii) perceived impact of illness, and (iii) analyse associations between perceived competence and demographic factors, disease-related factors and joint status in young haemophiliacs in the Netherlands. Fifty-four children (age 8-12 years) and 72 adolescents (12-18 years) with haemophilia participated in this cross-sectional, multi-centre, explorative study. Measurements included perceived competence (Self Perception Profile for Children/Adolescents; range 6-24/5-20), impact of disease (Revised Perception Illness Experience; range 1-5), demographic factors, disease-related factors, joint status and functional status. Mean (SD) scores for perceived competence in the children ranged from 17.3 (±4.0) to 19.6 (±4.0), and for adolescents from 13.3 (±2.4) to 15.7 (±2.8) points. In general, scores were comparable with those of healthy peers, but children with haemophilia had a lower global self-worth score and competence in close friendship was lower for adolescents when compared with those of healthy peers. Mean (SD) scores for impact of disease ranged from 1.2 (±0.4) to 2.3 (±0.8) in children and from 1.3 (±0.4) to 2.0 (±0.8) in adolescents. Severe haemophilia, prophylactic medication, high impact of disease and a shorter walking distance showed a weak to moderate association with perceived competence. Children and adolescents with haemophilia in general have a perceived competence that is nearly comparable with that of healthy peers, with the exception of a lower global self-worth in children and a lower competence for close friendship in adolescents. Haemophiliacs seem to perceive their disease as having relatively low impact on their life. Severe disease, prophylactic treatment and low functional status seemed to be associated with lower perceived competence.

Determination of N7-(2-hydroxyethyl)guanine by HPLC with electrochemical detection.

A method has been developed for the determination of N7-(2-hydroxyethyl)-guanine (N7-EtOHGua) via HPLC with electrochemical detection (EC). N7-EtOHGua is the major base adduct formed in DNA upon exposure to ethylene oxide. N7-EtOHGua, released from DNA, was separated from the unmodified nucleobases by chromatography on a reversed-phase column. For electrochemical detection, an amperometric detector cell was used with a glassy carbon working electrode, set at 1.35 V relative to an Ag/AgCl reference electrode. With purified N7-EtOHGua a linear dose-response relation was observed in the range between 0.11 and 13 pmol. The signal-to-noise ratio during analysis of 0.11 pmol N7-EtOHGua was about 8 to 1. Determination of adducts in a series of DNA samples treated with 0.16-10 mM ethylene oxide showed a linear dose-dependent increase in the level of N7-modifications. For DNA samples, the detection limit of this HPLC-EC analysis is 1 N7-EtOHGua per 6 x 10(6) nucleotides.

Minimally invasive coronary artery bypass grafting without cardiopulmonary bypass.

UNLABELLED: To determine the feasibility and the effectiveness of minimally invasive direct coronary artery bypass without cardiopulmonary bypass (MICABG) in patients with left anterior descending (LAD) coronary artery disease, we evaluated 90 consecutive patients who underwent MICABG at the University Hospital of Groningen. PATIENTS: Between January 1995 and December 1996, 50 patients (mean age 60 +/- 10.3 years) with documented myocardial ischemia and isolated stenosis of the LAD were selected for MICABG. Patients with any associated cardiac disease or with acute or evolving myocardial infarction were excluded. METHODS: A small left antero-lateral thoracotomy in the 5th intercostal space was made in all patients, anastomosing the left internal mammary artery (LIMA) to the LAD. A short-term (3 days) postoperative rehabilitation programme was used. Emotional stress (STAY-DY-1 score), wound pain (VAS: visual analogue score) and O2-saturation after a 6 min walking test were measured during hospitalisation and at the first follow-up examination (2.5 week after discharge). RESULTS: Mean operative time was 92 +/- 25 min (range 60-170). We recorded 1 (1.1%) in-hospital death and three cases (3.3%) of perioperative myocardial infarction. In two cases the MICABG was converted to the midline sternotomy. One patient underwent urgent reoperation on postoperative day 1 via midline sternotomy. Mean hospital stay was 4.4 +/- 2 days. Emotional stress was significantly reduced during and after hospitalisation, compared with the admission day. Wound pain was mild (3.5/10 VAS) on postoperative day 1 and reduced significantly during hospitalisation and at first follow-up examination. O2-saturation after a 6 min walking test had significantly improved at the first follow-up examination. CONCLUSION: These results indicate that MICABG is feasible and effective in patients with LAD stenosis and leads to a fast psycho-physical recovery.

Physical functioning and quality of life after cancer rehabilitation.

In order to overcome cancer-related problems and to improve quality of life, an intensive multi-focus rehabilitation programme for cancer patients was developed. We hypothesised that this six-week intensive rehabilitation programme would result in physiological improvements and improvement in quality of life. Thirty-four patients with cancer-related physical and psychosocial problems were the subjects of a prospective observational study. A six-week intensive multi-focus rehabilitation programme consisted of four components: individual exercise, sports, psycho-education, and information. Measurements (symptom-limited bicycle ergometry performance, muscle force and quality of life [RAND-36, RSCL, MFI]) were performed before (T0) and after six weeks of rehabilitation (T1). After the intensive rehabilitation programme, statistically significant improvements were found in symptom-limited bicycle ergometry performance, muscle force, and several domains of the RAND-36, RSCL and MFI. The six-week intensive multi-focus rehabilitation programme had immediate beneficial effects on physiological variables, on quality of life and on fatigue.

Exercise adherence in patients with trismus due to head and neck oncology: a qualitative study into the use of the Therabite.

Trismus is a common problem after treatment of head and neck cancer. The Therabite is an effective treatment for trismus. To explore the factors that may influence Therabite exercise adherence, how these interrelate and to provide aims for interventions to increase adherence, the authors conducted a multi-centre, formal-evaluative qualitative retrospective study. 21 patients treated for head-neck cancer were interviewed in semi-structured, in-depth interviews. Internal motivation to exercise, the perceived effect, self-discipline and having a clear exercise goal influenced Therabite exercise adherence positively. Perceiving no effect, limitation in Therabite opening range and reaching the exercise goal or a plateau in mouth opening were negative influences. Pain, anxiety and the physiotherapist could influence adherence both positively and negatively. Based on the results, a model for Therabite exercise adherence was proposed. It is important to signal and assess the factors negatively influencing Therabite adherence, specifically before there is a perceived effect. Research is needed to examine why some patients do not achieve results despite high exercise adherence, to identify effective exercise regimens and to assess proposed interventions aimed to increase Therabite exercise adherence.

Limiting factors of exercise performance 1 year after lung transplantation.

BACKGROUND: After lung transplantation (LTx) exercise capacity frequently remains limited, despite significantly improved pulmonary function. The aim of this study was to evaluate maximal exercise capacity and peripheral muscle force before and 1 year after LTx, and to determine whether peripheral muscle force and lactate threshold (LT) limit exercise capacity 1 year after LTx. METHODS: Twenty-five subjects (mean age 43 years, 8 women and 17 men, 4 single-lung transplantations) were included in the study. Measurements included maximal exercise capacity, lactate threshold (symptom-limited bicycle ergometer test) and muscle force test (hand-held dynamometer) were performed before and 1 year after LTx. RESULTS: Before LTx, all patients showed severe exercise intolerance (mean +/- SD): work capacity (W(peak)), 11.6 +/- 18 W; peak oxygen uptake (Vo(2)), 8.6 +/- 3.6 ml/min/kg. After LTx, exercise capacity improved significantly: W(peak), 69 +/- 27 W (p < 0.001); peak Vo(2), 15.7 +/- 4.3 ml/min/kg (p < 0.001). Ventilatory factors did not appear to limit exercise capacity. Quadriceps muscle force pre- vs post-LTx was: 248 +/- 73 N vs 281 +/- 68 N (p < 0.05). Post-LTx, a significant correlation was found between LT and exercise capacity (r = 0.76, p < 0.001), between muscle force and exercise capacity (r = 0.41, p < 0.05) and between the LT and muscle force (r = 0.53, p < 0.01). CONCLUSIONS: The occurrence of an early and pathologic LT and peripheral muscle weakness contributes to the limitation of exercise capacity and reflects a peripheral deficit post-LTx.

The isolation of monoclonal antibodies selected for the detection of imidazole ring-opened N7-ethylguanine in purified DNA and in cells in situ. Crossreaction with methyl, 2-hydroxyethyl and sulphur mustard adducts.

Monoclonal antibodies have been obtained against imidazole ring-opened N7-ethylguanine (RON7-EtGua) in DNA. The antibodies were selected for good performance in the ELISA with either DNA or nucleated blood cells as immobilized antigen. Antibodies thus selected were studied for their suitability for the in situ detection of RON7-EtGua in the nuclei of cells by means of immunofluorescence microscopy (IFM). Two antibodies have been characterized in detail with respect to specificity and sensitivity. Competitive ELISA demonstrated that the antibodies recognize not only RON7-EtGua but also the corresponding methyl and 2-hydroxyethyl components, with efficiencies that vary with the chemical environment (base, nucleoside or DNA), the nature of the alkyl group and the antibody. They have a clear specificity for the ring-opened alkyl adducts and show an at least 100-fold stronger preference for such structures in DNA when compared to the free nucleoside adducts. Furthermore, they hardly bind to non-alkylated DNA, and do not bind to guanosine or N1- or O6-ethylguanosine. Analysis by DNA-ELISA showed that the binding preference of antibody N7E-026 for ring-opened alkyl adducts is methyl approximately ethyl greater than 2-hydroxyethyl much greater than sulphur mustard, while that of N7E-102 is 2-hydroxyethyl greater than ethyl greater than methyl approximately sulphur mustard. Analysis of RON7-EtGua in DNA with competitive ELISA, DNA-ELISA and IFM showed that in all cases the lowest detection limit can be reached with antibody N7E-026. Competitive ELISA was the most sensitive method, followed by DNA-ELISA and IFM, with detection limits of 2.2, 16 and 23 RON7-EtGua/10(6) nucleotides respectively. In the DNA-ELISA, 12 methyl adducts/10(6) nucleotides can be detected with N7E-026 and 11 2-hydroxyethyl adducts/10(6) nucleotides with N7E-102.