Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0392674 (exhaustion)
 13,658 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the differential diagnosis of intermittent claudication some rare myopathies have to be considered. The most frequent is phosphorylase deficiency (McArdle's disease). Exercise-induced muscular pain, weakness, contractures and occasionally myoglobinuria are the most prominent clinical signs. Serum creatine phosphokinase, aldolase and lactic dehydrogenase may be elevated after exertion. In the ischemic forearm test there is no rise of serum lactic acid. The enzyme deficiency can be demonstrated by histochemical and biochemical examination of a muscle specimen. Further, but more infrequent, enzymatic disturbances of glycolysis are phosphofructokinase deficiency and phosphohexoisomerase inhibitor, which also yield an abnormal ischemic forearm test and must be demonstrated histochemically and biochemically. Apart from muscular signs, myopathy with lactic acidosis is associated with palpitation, dyspnea and exhaustion, and a disproportionate rise in serum lactic acid level after exertion. Histochemically and electronmicroscopically demonstrable fat accumulation in the muscle can be a sign of a disturbance in lipid metabolism. This type of exercise-induced myopathy has been reported only in a few cases with carnitine-pylmityltransferase deficiency, which has to be demonstrated biochemically. Muscular contractures also exercise-induced but painless and reversible within seconds may be due to deficient uptake of sarcoplasmic calcium in the tubular system. Dyskalemic paralysis causes painless paresis within minutes of hours after exertion, which disappears within hours to a few days. Myopathy with tubular aggregates can be differentiated from other exercise-induced myopathies by morphology. Myotonia combined with painful contractures characterizes myopathia myotonica.
 ...
PMID:[Exercise-induced muscular weakness, myalgia and contractures. I. A clinical review]. 13 80

Neuroblastoma cells, cultivated on plastic dishes, in presence of 15 mM glucose resist very well to hypoxia. Cells incubated on plastic dishes, if left unshaken, showed a Pasteur effect at an oxygen concentration below 10%. Oxygen diffusion was the limiting factor in these plastic dishes since improved oxygen diffusion, as a result of shaking, decreased the lactate production considerably at all oxygen concentrations used. When cells were cultivated on Petriperm((R)) dishes, coated with polylysine, oxygen diffusion was no longer a rate-limiting factor: less lactate was produced at 21% O(2) and hypoxia, down to 2.5% O(2) did not show any increase in the rate of lactate production, while Antimycin A drastically increased the glycolytic rate. A situation of limited oxygen availability resulted in two different kinds of adaptation of the neuroblastoma cells: first an instantaneous metabolic regulation leading to an increased glycolytic rate-the Pasteur effect-followed later by an increase in the activities of the glycolytic enzymes-hexokinase (EC 2.7.1.1), phosphoglucose isomerase (EC 5.3.1.9), 6-phosphofructokinase (EC 2.7.1.11), pyruvate kinase (EC 2.7.1.40) and lactate dehydrogenase (EC 1.1.1.27) and a simultaneous decrease of the mitochondrial cytochrome c oxidase (EC 1.9.3.1) activity. However, when the glucose concentration in the medium was decreased to 5 mM the cells were affected by hypoxia already at 5% O(2): cells released lactate dehydrogenase extracellularly and their protein content was decreased. This toxic effect of hypoxia was related to the exhaustion of the glucose supply.
 ...
PMID:Effect of oxygen and glucose availability on the glycolytic rate in neuroblastoma cells under different conditions of culture. 2048 70