Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To evaluate the frequency of the causes of exercise limitation in patients with chronic pulmonary disease and to assess the relationship between the resting pulmonary functional parameters and the degree of exercise dyspnea, we reviewed the data from 88 consecutive stable patients with chronic lung disease (62 COPD, 16 interstitial lung disease [ILD]). In each patient, the intensity of dyspnea was measured by a Borg scale (BS) during an incremental symptom-limited exercise test. COPD patients stopped exercise due to fatigue (46%), dyspnea (36%), cardiac limitation (12%), and peripheral circulatory limitation (6%). ILD patients stopped exercise due to dyspnea (62%), fatigue (25%), and cardiac limitation (12%). In all patients, dyspnea severity increased linearly with exercise intensity as measured as VO2, VE, and VE/MVV. The severity of dyspnea expressed as the slope of the relationship between BS and VE/MVV (DBS/D[VE/MVV]) showed in COPD a significant inverse correlation with VC, FEV1, MIP, and a positive correlation with PaCO2 and VE/MVV at rest. In ILD, DBS/D(VE/MVV) showed a significant inverse correlation with VC, FEV1, TLC, and PaO2 and a positive correlation with VE/MVV at rest. The predicting power of all equations was very low.
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PMID:Dyspnea on exercise. Pathophysiologic mechanisms. 157 44

Single and multi-strand stainless steel and cobalt-nickel alloy wires, with strand diameters from 26 to 46 microns, were fatigue tested using a modified rotating bending test to determine what factors are most important in controlling fatigue life. The relation between cyclic strain and cyclic life was determined for each material by cyclically straining test specimens at various strain ranges and recording the number of cycles to failure. The results show that (a) the fatigue curves of the 316LVM, MP35N, DBS, and Syntacoben wires are very similar and have many of the same fatigue characteristics of specimens of large cross section. (b) Multi-stranded wires have the same average fatigue life as their individual constituent strands, but the variance of that life is smaller. (c) Deformities in the wire, which are created during the manufacturing, appear to have the effect of shortening the fatigue life of these small section wires. (d) Observation of wire fracture surfaces show a relatively small crack propagation zone and a large fast fracture zone suggesting that most of the fatigue life of these small wires is in the original crack formation, which creates a large stress concentration and quickly leads to wire failure. (e) The size of the wire cross sectional area is of secondary importance compared to the amplitude of the maximum cyclic strain of the individual strands in determining fatigue life of the cable. To maximize the fatigue life of electrodes in vivo, the highest fatigue life for a given bending radius of curvature is desired. This suggests wire strands should be manufactured at the smallest diameter possible (without introducing structural flaws) to maximize service life.
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PMID:A study of the fatigue properties of small diameter wires used in intramuscular electrodes. 186 76

Nonmotor manifestations in Parkinson's disease (PD) encompass a range of clinical features, including neuropsychiatric problems, autonomic dysfunction, sleep disorders, fatigue, and pain. Despite their importance for patients' quality of life, the evidence base for their treatment is relatively sparse. Nevertheless, the last few years have seen a number of new trials starting that specifically address nonmotor features as an outcome measure in clinical trials. Large randomized, controlled trials in the last 3 years reported improvement of psychosis with the new selective serotonin 5-HT2A inverse agonist pimavanserin and of postural hypotension with the oral norepinephrine precursor droxidopa. Smaller new randomized, controlled trials support the effectiveness of Deep Brain Stimulation and opiates for pain, of rivastigmine for apathy and piribedil for apathy post-DBS, group cognitive behavioral therapy for depression and/or anxiety, continuous positive airway pressure for sleep apnea in PD and doxepin for insomnia, and of solifenacin succinate and transcutaneous tibial nerve stimulation for urinary symptoms. A number of new smaller or open trials as well as post-hoc analyses of randomized, controlled trials have suggested usefulness of other treatments, and new randomized, controlled trials are currently ongoing.
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PMID:New clinical trials for nonmotor manifestations of Parkinson's disease. 2637 23