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51.
Abstract

Background. The aim of the present study was to analyze the score of fatigue in a large cohort of Brazilian patients with SpA, comparing different disease patterns and its association with demographic and disease-specific variables.

Methods. A common protocol of investigation was prospectively applied to 1492 Brazilian patients classified as SpA according to the European Spondyloarthropathies Study Group (ESSG) criteria, attended at 29 reference centers. Clinical and demographic variables were recorded. Fatigue was evaluated using the first item of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) questionnaire.

Results. The mean BASDAI fatigue score was 4.20 ± 2.99. There was no significant difference in the fatigue score between the different SpA. Fatigue was higher in female patients (p < 0.001), with mixed (axial + peripheral) involvement (p < 0.001) and in those who did not practice exercises (p < 0.001). Higher scores of fatigue were significantly associated with inflammatory low back pain (p = 0.013), alternating buttock pain (p = 0.001), cervical pain (p = 0.001), and hip involvement (p = 0.005). Fatigue presented a moderate positive statistical correlation with Bath Ankylosing Spondylitis Functional Index (BASFI) (0.469; p < 0.001) and Ankylosing Spondylitis Quality of Life (0.462; p < 0.001).

Conclusion. In this large series of Brazilian SpA patients, higher fatigue scores were associated with female gender, sedentary, worse functionality, and quality of life.  相似文献   
52.
ObjectivesTo examine real-time relationships between social interactions and poststroke mood and somatic symptoms in participants’ daily environments.DesignProspective observational study using smartphone-based ecological momentary assessment (EMA) surveys 5 times a day for 2 weeks. Multilevel models were used to analyze data for concurrent and lagged associations.SettingCommunity.ParticipantsAdults (N=48) with mild stroke.InterventionsNot applicable.Main Outcome MeasuresEMA measures of self-appraisal of social interactions (confidence, satisfaction, and success), as well as mood (depression and anxiety) and somatic (pain and fatigue) symptoms.ResultsIn concurrent associations, increased depressed mood was associated with reduced ratings of all aspects of social interactions. Fatigue was associated with reduced ratings of social satisfaction and success. In lagged associations, increased anxious mood preceded increased subsequent social confidence. Higher average social satisfaction, confidence, and success were related to lower momentary fatigue, anxious mood, and depressed mood at the next time point. Regarding clinicodemographic factors, being employed was concurrently related to increased social interactions. An increased number of comorbidities predicted higher somatic, but not mood, symptoms at the next time point.ConclusionsThis study provides preliminary evidence of dynamic relationships between social interactions and somatic and mood symptoms in individuals with mild stroke. Interventions to not only address the sequelae of symptoms, but also to promote participation in social activities in poststroke life should be explored.  相似文献   
53.
BackgroundAdequate footwear is an important factor for reducing the risk of slipping; as shoe outsoles wear down, friction decreases, and slip and fall risk increases. Wear theory suggests that gait kinetics may influence rate of tread wear.Research questionDo the kinetics of walking (i.e., the shoe-floor force interactions) affect wear rate?MethodsFourteen participants completed dry walking trials during which ground reaction forces were recorded across different types of shoes. The peak normal force, shear force, and required coefficient of friction (RCOF) were calculated. Participants then wore alternating pairs of shoes in the workplace each month for up to 24 months. A pedometer was used to track the distance each pair of shoes was worn and tread loss was measured. The wear rate was calculated as the volumetric tread loss divided by the distance walked in the shoes. Three, mixed linear regression models were used to assess the impact of peak normal force, shear force, and RCOF on wear rate.ResultsWear rate was positively associated with peak RCOF and with peak shear force, but was not significantly related to peak normal forces.SignificanceThe finding that shear forces and particularly the peak RCOF are related to wear suggests that a person’s gait characteristics can influence wear. Therefore, individual gait kinetics may be used to predict wear rate based on the fatigue failure shoe wear mechanism.  相似文献   
54.
Postural instability can be the result of various factors, including fatigue. Although it is well known that exercise-induced fatigue may be responsible for a decrease in performance, its effects on postural control, as well as those of hydration, have been relatively little explored. This study evaluated the effects of fatigue, with and without rehydration, on postural control in 10 healthy subjects who regularly practice sports activities. All subjects were submitted to three types of ergocycle exercises: maximal oxygen uptake (Vo2max) and submaximal exercises in no-hydrated and hydrated conditions at a power corresponding to approximately 60% of the Vo2max of each subject. Static posturographic tests were performed immediately before (control) and after exercises. The postural control performance decreased from the best to the worst: control, hydration, dehydration, and Vo2max. Fast Fourier transformation of the center of foot pressure showed three patterns of amplitude spectral density, with an increase of spectral amplitude for dehydration, more important for Vo2max conditions. Spectral amplitudes for control and hydration conditions were relatively similar. This hierarchy suggests that fatigue mainly alters muscular effectors and sensory inputs, such as proprioception, resulting in poor postural regulation. Moreover, fluid ingestion could be responsible for the preservation of muscular functions and of sensory afferences accurately regulating postural control.  相似文献   
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PurposeThe aim of this study was to assess the effect of overnight shifts (ONS) on radiologist fatigue, visual search pattern, and diagnostic performance.MethodsThis experimental study was approved by the institutional review board. Twelve radiologists (five faculty members and seven residents) each completed two sessions: one during a normal workday (“not fatigued”) and another in the morning after an ONS (“fatigued”). Each radiologist completed the Swedish Occupational Fatigue Inventory. During each session, radiologists viewed 20 bone radiographs consisting of normal and abnormal findings. Viewing time, diagnostic confidence, and eye-tracking data were recorded.ResultsSwedish Occupational Fatigue Inventory results demonstrated worsening in all five variables (lack of energy, physical exertion, physical discomfort, lack of motivation, and sleepiness) after ONS (P < .01). Overall, participants demonstrated worse diagnostic performance in the fatigued versus not fatigued state (P < .05). Total viewing time per case was longer when fatigued (35.9 ± 25.8 seconds) than not fatigued (24.8 ± 16.3 seconds) (P < .0001). Total viewing time per case was longer for residents (P < .05). Mean total fixations generated during the search increased by 60% during fatigued sessions (P < .0001). Mean time to first fixate on the fracture increased by 34% during fatigued sessions (P < .0001) and was longer for residents (P < .01). Dwell times associated with true- and false-positive decisions increased, whereas those with false negatives decreased.ConclusionsAfter ONS, radiologists were more fatigued with worse diagnostic performance, a 45% increase in view time per case, a 60% increase in total gaze fixations, and a 34% increase in time to fixate on the fracture. The effects of fatigue were more pronounced in residents.  相似文献   
58.
SUMMARY

The National Health Service (NHS) Cancer Plan published in 2000 has a short-term focus on the most pressing problems of improving survival rates and replacing equipment. It also mentioned as a target 'improved quality of life for those affected by cancer'. Continuity of care for longer-term care programmes was seen predominantly in terms of palliative care. Recent National Institute for Clinical Excellence (NICE) reports may have reinforced this approach by focussing on the clinical and cost effectiveness of chemotherapy for late-stage cancer. The impact on local decision-makers has been that drug funds have been prioritised for use on survival-enhancing interventions, with few resources left for short and longer-term supportive care targeted primarily on improving quality of life. Within supportive care, resources are particularly limited for funding treatments such as erythropoietin for the management of cancer-related anaemia, a common and very debilitating side-effect of intensive therapy. The need for a re-focusing on supportive care is associated with cancer becoming, in many instances, a longer-term illness. The prevalence of

cancer is rising markedly due to increased survival rates. However, this creates a new challenge of reducing disability and improving quality of life. In surveys, patients have rated fatigue associated with anaemia as one of the most debilitating effects of their cancer and its treatment with chemotherapy. This paper reviews the evidence demonstrating the quality of life benefits of erythropoietin, and then considers the policy constraints that have limited the adoption of this treatment within the NHS. Through co-ordinated planning there are opportunities for cancer networks and primary care trusts (PCTs) working with cancer centres to develop more support in ways which are feasible and fundable. The case is argued that PCTs and cancer networks, in implementing the Cancer Plan locally, need to integrate short- and longer-term supportive care into their cancer service development plans, and recognise the importance of anaemia management as an integral part of this. Lessons can be learnt from UK renal services where anaemia management with erythropoietin is standard practice.  相似文献   
59.
Understanding the behaviour of implantable medical devices is of obvious importance. The potential for failure of a medical device can often be associated with issues related to cyclic loading of the device, and material fatigue. Detailed finite element simulations to evaluate the fatigue of stents allow the engineer to assess potential failures. The engineer can then use the analysis results to modify the design and prevent failure, without making and testing numerous physical devices. Complete understanding of the mechanical behaviour of a stent provided by finite element analysis has the benefits of facilitating effective design, helping to reduce time to market and minimising the potential for unwanted failures.  相似文献   
60.
Neck-stem modularity gained recent popularity in hip arthroplasty for clinical advantages, and few complications have been reported. We describe an unusual two-stage failure of the bimodular neck of a cementless forged titanium alloy stem implanted 12 years before. The retrieved neck was forwarded to the manufacturer for metallurgic evaluation and failure analysis. Lengthening and bending of the superolateral aspect of the neck and double depression of the medial part prove that the prosthetic neck underwent a medial displacement and a varus rotation. The crack initiated from the superolateral corner of the fracture section, and the neck probably underwent two subsequent unstable configurations. The first horizontal part of the fracture occurred in the external surface as a result of physiological load carried on abnormal conditions of frictions. Due to increased oscillations, the end of the fracture section knocked against the inner aspect of the proximal hole of the stem, preventing further valgus displacement of the neck, which was moved forward. Consequently, the neck achieved a second unstable configuration, and the fracture propagated in the weaker direction creating a bent track. Finally, the neck broke unexpectedly as a result of the traumatic event. An incorrect placement into the femoral component during surgery was the initiation of the failure of the bimodular neck. The transitory but repeated interface motion between the neck and the stem induced a local surface irregularity acting as a starting point for crack propagation of fatigue fracture. Final failure followed a direct trauma.  相似文献   
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