Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.8 (FAST)
 758 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Passive sensitization of human airways in vitro causes increased responsiveness to histamine and induces specific immunoglobulin (Ig)E-dependent contractile responsiveness to allergen. Leukotrienes (LTs) and, to a lesser extent, histamine are the major mediators of allergen-induced contraction. Since it is unclear whether passively sensitized airways are also hyperresponsive to cysteinyl leukotrienes, this study investigated the effect of passive sensitization on LTC4-, in addition to histamine- and allergen-induced contractions in vitro. Bronchial rings from nine nonatopic patients were sensitized overnight with serum containing high levels of total IgE (>250 U x mL(-1)) and allergen-specific IgE against Dermatophagoides farinae (fluorescence allergosorbent test) (FAST class > or =3). The potency (-log10 of the mediator concentration causing a half maximal response (pEC50) of histamine was significantly increased in serum-sensitized tissues compared to nonsensitized controls ((mean+/-SEM) pEC50 5.20+/-0.27 versus 5.64+/-0.18; p=0.02) and maximal contractions were enhanced (877+/-47 versus 543+/-51 mg; p<0.0001). Similarly, the potency of LTC4 was significantly increased in sensitized compared to nonsensitized bronchial rings (pEC50 9.37+/-0.20 versus 8.66+/-0.26; p=0.004); maximal contractions were also enhanced (811+/-57 versus 361+/-86 mg; p<0.0001). These data demonstrate that passive sensitization of human airways induces an increase not only in histamine but also in leukotriene responsiveness. Therefore, it might be speculated that allergen responses in sensitized airways are effected through a combination of increased mediator release from inflammatory cells and increased responsiveness of airway smooth muscle.
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PMID:Passive sensitization of human airways increases responsiveness to leukotriene C4. 1051 7

We compared changes in muscle fibre composition and muscle strength indices following a 10 week isokinetic resistance training programme consisting of fast (3.14 rad x s(-1)) or slow (0.52 rad x s(-1)) velocity eccentric muscle contractions. A group of 20 non-resistance trained subjects were assigned to a FAST (n = 7), SLOW (n = 6) or non-training CONTROL (n = 7) group. A unilateral training protocol targeted the elbow flexor muscle group and consisted of 24 maximal eccentric isokinetic contractions (four sets of six repetitions) performed three times a week for 10 weeks. Muscle biopsy samples were obtained from the belly of the biceps brachii. Isometric torque and concentric and eccentric torque at 0.52 and 3.14 rad x s(-1) were examined at 0, 5 and 10 weeks. After 10 weeks, the FAST group demonstrated significant [mean (SEM)] increases in eccentric [29.6 (6.4)%] and concentric torque [27.4 (7.3)%] at 3.14 rad x s(-1), isometric torque [21.3 (4.3)%] and eccentric torque [25.2 (7.2)%] at 0.52 rad x s(-1). The percentage of type I fibres in the FAST group decreased from [53.8 (6.6)% to 39.1 (4.4)%] while type IIb fibre percentage increased from [5.8 (1.9)% to 12.9 (3.3)%; P < 0.05]. In contrast, the SLOW group did not experience significant changes in muscle fibre type or muscle torque. We conclude that neuromuscular adaptations to eccentric training stimuli may be influenced by differences in the ability to cope with chronic exposure to relatively fast and slow eccentric contraction velocities. Possible mechanisms include greater cumulative damage to contractile tissues or stress induced by slow eccentric muscle contractions.
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PMID:Adaptation to chronic eccentric exercise in humans: the influence of contraction velocity. 1160 16