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)

1. The effect of aminophylline and terbutaline sulfate, separately and in combination, on the contractility of the feline diaphragm was investigated. 2. Diaphragmatic contractility increased significantly (P less than 0.05) to 28.3% above control level as long as theophylline plasma levels were maintained between 10-20 mg/l (mean 13.9 +/- 0.8 mg/l). 3. Diaphragmatic contractility showed a significant (P less than 0.05) 41.5% increase after i.v. administration of terbutaline sulfate as a maintenance dose of 1.4 micrograms/kg-hr, and the increase leveled off after 180 min. 4. Administering the two drugs in combination showed a significant (P less than 0.05) 27.3% increase which suggests a non-synergistic effect of aminophylline and terbutaline sulfate on diaphragmatic contractility. 5. By enhancing the contractility of the diaphragm, aminophylline and terbutaline sulfate may improve the clinical status of patients with airway obstructive diseases and help in preventing respiratory muscle fatigue.
Gen Pharmacol 1991
PMID:Effects of aminophylline and terbutaline sulfate on the contractility of feline diaphragm. 181 Aug 14

The role of extracellular K+ concentration in the propagation velocity of action potential was tested in isolated rat skeletal muscles. Different K+ concentrations were produced by KCl additions to extracellular solution. Action potentials were measured extracellularly by means of two annular platinum electrodes. Fibre bundles of m. soleus (SOL), m. extensor digitorum longus (EDL), red (SMR) and white (SMW) part of m. sternomastoideus were maximum stimulated. The conduction velocity (c.v.) was calculated from the distance between the electrodes and the time delay of the potentials measured at 22 degrees C. In Tyrode solution containing 5 mmol/l K+, the c.v. was close to 1 m.s-1. Bundles of the fast muscle type seemed to have a somewhat higher c.v. The differences observed in these studies were not significant. At higher temperatures, the c.v. increased (Q10 of approx. 2) and a dissociation between SMR and SMW muscles appeared. An elevation of K+ concentration to 10 mmol/l induced a drop of the c.v. by approx. 25% and 15% in EDL and SOL muscles, respectively. After return to normal solution, the recovery was not complete within 30 min. In K+ free solution the c.v. of EDL and SM muscles rose by a factor of 1.5, but less in SOL muscles. The weaker response of SOL to K+ modification was related to the higher resistance of this muscle to fatigue. This suggestion was supported by experiments on fatigued fibre bundles. Immediately after a tetanic stimulation producing fatigue, the c.v. of EDL and SOL muscles dropped similarly as in 10 mmol/l K+; again, the drop was less for SOL muscles. Adrenaline (0.5-10.0 mumol/l) enhanced both the c.v. and the twitch amplitude. The results support the suggestion that extracellular K+ accumulation during activity is an essential factor of muscle fatigue.
Gen Physiol Biophys 1991 Oct
PMID:External potassium and action potential propagation in rat fast and slow twitch muscles. 181 28

To determine whether there was a metabolic basis for recent reports that bulimic patients had low energy requirements for weight maintenance, energy expenditure measurements were made in 15 women with bulimia nervosa during abstinence from bingeing and vomiting. Resting metabolic rate, adjusted for differences in lean body mass, was significantly lower in bulimics (mean +/- SE, 4201 +/- 126 kJ/d) than healthy volunteers (4694 +/- 172 kJ/d). Bulimic patients had a blunted increase in oxygen consumption in response to low and moderate levels of exercise (421 +/- 16 and 689 +/- 17 mL/min) compared with values for healthy volunteers (491 +/- 28 and 795 +/- 26 mL/min). Plasma triiodothyronine (1.1 +/- 0.07 vs 1.4 +/- 0.08 nmol/L) levels, plasma norepinephrine levels in supine (0.58 +/- 0.04 vs 1.06 +/-0.17 nmol/L) and standing (1.34 +/- 0.15 vs 2.46 +/- 0.30 nmol/L) subjects, and the increase in norepinephrine levels during orthostatic challenge (0.76 +/- 0.15 vs 1.40 +/- 0.25 nmol/L) all were significantly less in bulimics than volunteers. These results are consistent with previous reports of decreased energy requirements for weight maintenance and decreased plasma levels of metabolism-related hormones in patients with bulimia. However, the effects of reduced energy intake in metabolic studies of patients with bulimia need to be further investigated.
Arch Gen Psychiatry 1991 May
PMID:Reduced resting metabolic rate in patients with bulimia nervosa. 202 Dec 98

1. Nifedipine (1.5-3.0 x 10(-5) M) potentiated the (sub)tetanic tension during 10-50 Hz indirect or direct stimulation of the rat diaphragm preparation; the twitch contractions were not potentiated. 2. The effect was antagonized in high Ca2+ (5-10 x normal) solutions. 3. A comparison with the twitch potentiators caffeine (1.0 x 10(-3) M), quinine (1.4 x 10(-5) M) and phenytoin (2.0 x 10(-5) M), showed that only phenytoin, a putative Ca-antagonist, caused a nifedipine-like frequency-dependent potentiation, indicating a Ca-antagonistic rather than an unspecific effect. 4. A similar (sub)tetanic potentiation was found in a K(+)-free solution. 5. The slow development of the potentiation during repetitive stimulation is in accordance with an effect on the slow Ca channels known to be present in mammalian skeletal muscle. 6. A delay of the fatigue-inducing accumulation of K+ in the T tubules, which may occur during a nifedipine-induced reduction of a Ca2(+)-stimulated K+ efflux, as well as in a K(+)-free solution, may explain the effect.
Gen Pharmacol 1991
PMID:Selective potentiation of subtetanic and tetanic contractions by the calcium-channel antagonist nifedipine in the rat diaphragm preparation. 205 26

Twenty-two coffee drinkers (three to seven cups per day) underwent repeated double-blind trials to test for caffeine self-administration, withdrawal, and adverse effects. Each trial consisted first of a randomized crossover period of 1 day of decaffeinated coffee and 1 day of caffeinated coffee (100 mg) to assess withdrawal and adverse effects of caffeine. Next, subjects were given 2 days of concurrent access to the two coffees. The relative use of the two coffees was used to assess caffeine self-administration. Reliable caffeine self-administration occurred in three of 10 subjects in study 1 and seven of 12 subjects in study 2. Withdrawal symptoms were headaches, drowsiness, and fatigue. The major adverse effect from self-administration was tremulousness. The occurrence of headaches on substitution of decaffeinated coffee prospectively predicted subsequent self-administration of caffeine. These results indicate that some coffee drinkers exhibit signs of a caffeine dependence, ie, they self-administer coffee for the effects of caffeine, have withdrawal symptoms on cessation, and experience adverse effects.
Arch Gen Psychiatry 1991 Jul
PMID:Caffeine self-administration, withdrawal, and adverse effects among coffee drinkers. 206 91

A case definition for post-viral fatigue syndrome is proposed within which various subgroups of patients exist. Any one treatment may not apply to all the subgroups. In particular, patients' experiences do not show that avoidance of exercise is maladaptive. It is proposed that the recently ill often try to exercise to fitness whereas the chronically ill have learnt to avoid exercise. Recovery is more likely to be achieved if patients learn about their illness and do not exhaust their available energy.
Br J Gen Pract 1990 Jan
PMID:Patient management of post-viral fatigue syndrome. 210 60

We evaluated the immediate and long-term effects on psychological distress and coping methods of a 6-week, structured, psychiatric group intervention for postsurgical patients with malignant melanoma. The intervention consisted of health education, enhancement of problem-solving skills, stress management (eg, relaxation techniques), and psychological support. In spite of good prognosis, most patients had high levels of psychological distress at baseline, comparable with other patients with cancer. However, at the end of brief psychiatric intervention, the experimental subjects (n = 38), while not without some distress, exhibited higher vigor and greater use of active-behavioral coping than the controls (n = 28). At 6 months' follow-up, the group differences were even more pronounced. The intervention-group patients then showed significantly lower depression, fatigue, confusion, and total mood disturbance as well as higher vigor. They were also using significantly more active-behavioral and active-cognitive coping than the controls. These results indicate that a short-term psychiatric group intervention for patients with malignant melanoma effectively reduces psychological distress and enhances longer-term effective coping.
Arch Gen Psychiatry 1990 Aug
PMID:A structured psychiatric intervention for cancer patients. I. Changes over time in methods of coping and affective disturbance. 237 43

Simple rehabilitative strategies are proposed to help patients with the chronic fatigue syndrome. A model is outlined of an acute illness giving way to a chronic fatigue state in which symptoms are perpetuated by a cycle of inactivity, deterioration in exercise tolerance and further symptoms. This is compounded by the depressive illness that is often part of the syndrome. The result is a self-perpetuating cycle of exercise avoidance. Effective treatment depends upon an understanding of the interaction between physical and psychological factors. Cognitive behavioural therapy is suggested. Cognitive therapy helps the patient understand how genuine symptoms arise from the frequent combination of physical inactivity and depression, rather than continuing infection, while a behavioural approach enables the treatment of avoidance behaviour and a gradual return to normal physical activity.
J R Coll Gen Pract 1989 Jan
PMID:Management of chronic (post-viral) fatigue syndrome. 256 12

Researchers initiated a randomized double blind crossover trial as part of a community based postal survey of menstrual patterns of 68 women in England. Each woman jotted down daily the severity of symptoms (e.g., depression, headache, etc.). After this 1st study cycle and being randomly assigned to the pyridoxine or placebo group, they either took 50 mg/day of pyridoxine or placebo tablets for 3 months. At the end of 3 months, they followed the other treatment. 37 women completed 6 months and only 32 completed the full 7 months. The results of the study show pyridoxine to significantly affect emotional type symptoms (depression, irritability, and tiredness [p.05]), but not somatic (headache, breast discomfort, swollen abdomen, swollen hands or feet) or menstrual (stomach cramps, backache, other) symptoms. Women who took oral contraceptives (OCs) had nonsignificant higher adjusted premenstrual symptom scores, particularly for emotional type symptoms, during both pyridoxine and placebo months that did those who did not take OCs. This study was complicated by a placebo effect. It revealed a significant decrease in the level of all symptom scores from the 1st month to the 4th month by a mean of 57% (p=.001) when the women took the placebo initially. Emotional type symptoms decreased by 69% (p.05), somatic type by 52% (p.05), and menstrual type nonsignificantly by 15%. On the other hand, when women took the placebo after taking pyridoxine for a month, the combined level of all symptom scores only increased 37% on average (nonsignificant). Based on the results of this study, pyridoxine appears to alleviate premenstrual depression. Further research is needed to confirm the results of this and other similar studies.
J R Coll Gen Pract 1989 Sep
PMID:Pyridoxine (vitamin B6) and the premenstrual syndrome: a randomized crossover trial. 255 86

The current definition of Somatization Disorder requires the assessment of each of 35 symptoms, 13 of which have to be scored as meeting special criteria (e.g., not due to medical reasons) in order to make the diagnosis. The detailed questioning and probing about each symptom can be quite elaborate--hence the interest in developing briefer screening indexes. This study evaluated two sets of screening indexes for Somatization Disorder (those of Othmer and DeSouza and Swartz and colleagues) that had been previously developed in psychiatric and community samples. One hundred medical outpatients with chronic fatigue constituted the study sample. The patients underwent thorough medical evaluations and were administered the Diagnostic Interview Schedule (DIS) to make the psychiatric diagnoses. Of the two screening sets, the one developed in a psychiatric outpatient sample (Othmer and DeSouza's) had the best sensitivity. Although a screening index derived from the DIS interviews of this group of patients also had excellent sensitivity, we support the use of Othmer and DeSouza's index in medical outpatients with a chief complaint of chronic fatigue.
Gen Hosp Psychiatry 1989 Jul
PMID:Screening for somatization disorder in patients with chronic fatigue. 266 39


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