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)

Drowsiness is a common complaint among patients with epilepsy taking antiepileptic drugs (AEDs) and may be of particular importance because of the potential effects on cognitive abilities. We used a novel EEG-based measure (the Awake Maintenance Task, AMT) to determine objectively whether patients on chronic, stable AED therapy had impaired ability to maintain wakefulness. Thirty patients receiving AEDs [carbamazepine (CBZ), phenytoin (PHT), phenobarbital (PB), valproate (VPA)] were compared to 35 healthy controls, 12 seizure patients not taking AEDs, and 16 patients with multiple sclerosis. A structured EEG recording was conducted under controlled conditions, and subjects were tested to determine their ability to maintain wakefulness during a 6-min unstimulated trial. Testing also included Digit Symbol, auditory reaction time, and subjective measures of fatigue or sleepiness [Profile of Mood States (POMS), Stanford Sleepiness Scale (SSS)]. Patients receiving AEDs had a mean total drowsiness score of 101 s compared with < or = 12 s for each of the three control groups (P < 0.001). One third of the AED-treated patients had > 120 s of drowsiness, in contrast to only 1 of 63 controls (p < 0.001). Among patients receiving AEDs, objective EEG drowsiness did not correlate with AED levels or performance measures. Untreated seizure patients had significantly greater complaints of lack of vigor despite a near absence of objective drowsiness on the AMT. These results suggest that epilepsy patients receiving chronic AED therapy have impaired ability to maintain wakefulness. Patient self-reports of AED-related sleepiness may not accurately represent this problem.
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PMID:Assessment of drowsiness in epilepsy patients receiving chronic antiepileptic drug therapy. 863 29

Previous studies have shown that the motor evoked potential (MEP) amplitude increases as force declines during a fatiguing muscle contraction, indicating that there is an increase in corticomotor excitability. In spite of this there is a progressive reduction in voluntary motor drive, as shown by an increase in the interpolated twitch force as fatigue develops. The aim of this study was to determine whether, by further increasing corticomotor excitability using a paired-pulse rTMS protocol designed to induce I-wave facilitation (iTMS), force loss during a sustained voluntary contraction could be reduced. We designed a cross-over study incorporating a 15-min period of iTMS (ISI 1.5 ms; 0.2 Hz; approximately AMT), following which MEP amplitude (first dorsal interosseous muscle) increased to 194 +/- 38% of baseline (P < 0.05), compared to a control period of stimulation that did not increase MEP amplitude (single-pulse TMS; 0.2 Hz; approximately 1.2 AMT). Eight right-handed healthy subjects received both iTMS and control stimulation, in a randomized order, a week apart. We measured percentage force loss at the end of a 10-s maximum right hand key-pinch task, and compared force loss before and after stimulation. There was an improvement in task performance following iTMS, with a reduction in force loss compared to pre-stimulation baseline (11.3 +/- 2.0 vs. 17.6 +/- 2.4%; post vs. pre; P < 0.05). There was no significant difference in force loss before and after control stimulation. The results indicate that by increasing corticomotor excitability using paired-pulse rTMS at trans-synaptic intervals, maximum voluntary force can be sustained at a higher level during a brief fatiguing maximal voluntary contraction.
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PMID:Paired-pulse rTMS at trans-synaptic intervals increases corticomotor excitability and reduces the rate of force loss during a fatiguing exercise of the hand. 1678 55

This study investigated the effect of prolonged walking with load carriage on body posture, muscle fatigue, heart rate and blood pressure of the tested subjects. Ten healthy volunteers performed 30 min walking trials on treadmill (speed = 1.1 m/s) with different backpack loads [0% body weight (BW), 10% BW, 15% BW and 20% BW]. The change of body posture, muscle fatigue, heart rate and blood pressure before and after walking and the recovery of muscle fatigue during the rest time (0, 5, 10 and 15 min) were collected using the Bortec AMT-8 and the NDI Optotrak Certus. Results showed that the forward trunk and head angle, muscle fatigue, heart rate and blood pressure increased with the increasing backpack loads and bearing time. With the 20% BW load, the forward angle, muscle fatigue and systolic pressure were significantly higher than with lighter weights. No significantly increased heart rate and diastolic pressure were found. Decreased muscle fatigue was found after removing the backpack in each load trial. But the recovery of the person with 20% BW load was slower than that of 0% BW, 10% BW and 15% BW. These findings indicated that the upper limit of backpack loads for college-aged students should be between 15% BW and 20% BW according to muscle fatigue and forward angle. It is suggested that backpack loads should be restricted to no more than 15% BW for walks of up to 30 min duration to avoid irreversible muscle fatigue.
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PMID:[Effect of different backpack loads on physiological parame ters in walking]. 2576 7