leukotriene e4

Measurement of urinary leukotriene E4 (LTE4) is a sensitive and noninvasive method of assaying total body cysteinyl leukotriene production and changes in cysteinyl leukotriene levels in specific microenvironments, such as the airway...

Urinary leukotriene E4 (LTE4) concentrations have been measured in six asthmatic patients with aspirin sensitivity and in five asthmatic subjects tolerant of aspirin, before and after provocation with aspirin or placebo...

..Thus, the P2Y12 receptor is required for proinflammatory actions of the stable abundant mediator LTE4 and is a novel potential therapeutic target for asthma...

..52 episodes per 100 patient-years, P = 0.038). LTE(4) levels are elevated in children with SCD when compared with controls. LTE(4) levels are associated with an increased rate of hospitalizations for pain...

Urinary leukotriene E4 (LTE4) concentrations were measured in six asthmatic subjects after treadmill exercise, and in five asthmatic subjects after allergen challenge...

Baseline level of the cysteinyl leukotriene (CysLT), leukotriene E4 (LTE4), is associated with an increased pain rate in children and adults with sickle cell disease (SCD)...

..This LTE(4)-selective receptor-mediated pathway may explain the unique physiologic responses of human airways to LTE(4) in vivo...

..This has stimulated a search for additional LT receptors that would respond preferentially to LTE(4) stimulation...

..Since LTE4 recruits granulocytes, the potential of antisulphidopeptide leukotriene drugs as anti-inflammatory and "steroid-sparing" agents should be tested...

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BACKGROUND: The urinary leukotriene E4 (U-LTE4) concentration is significantly increased in patients with aspirin-intolerant asthma (AIA)...

..However, the negative association of urinary 9 alpha, 11 beta-PGF(2) with lung function suggests an adverse effect of chronic PGD(2) production on lung function in asthma, irrespective of severity...

Allergen challenge is associated with an increased excretion of urinary leukotriene E4. The source of this increase is unknown, although the lack of effect of inhaled beta-agonists and sodium cromoglycate suggests that airway mast cells ..

..454, p = 0.012). CONCLUSION: EBC cys-LTs may be useful as a noninvasive marker assessing airway inflammation and hyperreactivity in children with asthma...

..b>Leukotriene E4 (LTE4; a stable metabolic product of LTC4 and LTD4) and histamine were measured in the blood draining the site ..

..Arsenic exposure also increases leukotriene E4 (LTE4) formation in both the mice and BAECs, an effect that is partially reversed by the addition of Nomega-..

..68; p = 0.001). No significant increase in urinary LTE4 levels occurred during the LAR. These results suggest that the LTE4 precursors, LTC4 and LTD4, are important bronchoconstrictor mediators causing EARs after allergen inhalation...

..The effects of leukotriene receptor antagonists (LTRAs) on exhaled leukotriene and prostanoids in children with asthma are unknown...

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The urinary excretion of leukotriene E4 (LTE4) was measured in subjects presenting for emergency treatment of airway obstruction...

..These results suggest cysteinyl leukotrienes play a role in eosinophil migration into the airways in allergic asthma, and for the same degree of bronchoconstriction, inhaled LTE(4) causes more tissue and airway eosinophilia than LTD(4)...

1. Preincubation of guinea-pig tracheal smooth muscle with leukotriene E4 (LTE4) in vitro increased its subsequent responsiveness to histamine. 2...

The FEV1 and urinary leukotriene E4 (LTE4) concentrations were determined in six aspirin-sensitive and six non-aspirin-sensitive asthmatic subjects before and after inhalation challenge with lysine-aspirin or placebo solution...

..68 +/- 0.46, and this was significantly decreased compared with that on the placebo day (p = 0.02). This suggests that LTE4-induced enhanced responsiveness to histamine is mediated in part by cyclooxygenase pathway-derived products...

..mass spectrometry (LC/MS/MS) with a column-switching system was developed for quantitative determination of leukotriene E4 (LTE4) in human urine...

..A positive linear relationship between increased urinary excretion of mevalonate and LTE4 (n = 5) suggests that increased cysteinyl leukotriene synthesis is involved in the pathomechanisms of this disease...

..The analyses showed that the P2Y12, P2Y13, P2Y14, GPR87, CysLT-1, and CysLT-2 receptors formed a P2Y-related receptor subfamily with common sequence motifs in the transmembrane regions...

..Addition of a leukotriene receptor antagonist such as montelukast improves asthma in aspirin-intolerant patients over and above what can be achieved by glucocorticosteroids...

..little experimental evidence that substantiates the relationship between nasal blockage severity and urinary leukotriene E4 (U-LTE4) concentration in patients with seasonal allergic rhinitis (SAR)...

..These studies provide evidence that leukotrienes are released in vivo in man after antigen challenge and in acute asthma...

b>Leukotriene E4 (LTE4) is excreted into the urine in a relatively constant proportion of 4-7% when either leukotriene C4 (LTC4) or LTE4 is intravenously infused, regardless of the magnitude of the infused dose...

..The major metabolites of LTE4 might be useful in assessing in vivo production of sulfidopeptide leukotrienes in humans...

..Our findings establish the existence of a third receptor, CysLT(E)R, that responds preferentially to LTE(4), the most abundant cys-LT in biologic fluids, and thus reveal a new target for therapeutic intervention...

..Pranlukast inhibits contraction of the tracheal muscle, and thereby antagonizes the binding of LTC4, LTD4 and LTE4. However, the action of pranlukast on monocytes/macrophages and T cells is unknown...

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..Montelukast (MK), a specific CysLT1 receptor antagonist, is metabolized in two main hydroxylated metabolites (termed M5 and M6, respectively)...

..The second leukotriene peak at 7 days is likely to follow a different pathway and might be related to a production in macrophages or activated glia...

..We hypothesised that adenosine induced bronchoconstriction in asthmatic patients may be blocked by pretreatment with the orally active selective cysteinyl leukotriene-1 (CysLT(1)) receptor antagonist, montelukast...

..These results strongly suggest that the observed effects of decreased SLT release after omalizumab treatment were attributable to the treatment with omalizumab, rather than to SIT therapy...

..Increased bronchial responsiveness to the released mediators could explain the exclusive bronchoconstriction in asthmatic subjects...

..The possibility that cysteinyl LTs bind effectively to their target receptors in BALF and, thus, decrease free LT concentrations deserves further study...

..Leukotriene were detected by enzymatic Leukotriene E4, EIA Kit, Cayman Chemical test...

..Thus, our results suggest that E254K in the 5-LO might be associated with BA...

..at the same time points for enzyme-linked immunosorbent assay measurement of leukotriene B4 in tears and leukotriene E4 in urine. RESULTS: Eight of the 10 patients evaluated reported a reduction in symptoms at the end of treatment...

..Urinary levels of leukotriene E4 were measured before and 2 hours after exercise...

..Eosinophils contain preformed stores of IL-4 within their cytoplasmic granules, but physiologic stimuli to release IL-4 from eosinophils are not yet defined...

..The suppressive effect by montelukast demonstrates that this is a cysLT(1) receptor-mediated effect...

..CONCLUSION: Patients with AIA and ATA react similarly to exercise challenge and obtain similar protection against EIB by montelukast...

..The increased biliary excretion of biologically active cysteinyl LTs may contribute to the aggravation of cholestasis and inflammatory reaction in obstructive jaundice...

..Cysteinyl leukotrienes (CysLTs) are important mediators of asthma in children. Predictors of susceptibility to CysLT effects have not been developed...

The cysteinyl leukotrienes, leukotriene C4 (LTC4), leukotriene D4 (LTD4) and leukotriene E4 (LTE4), activate contractile and inflammatory processes via specific interaction with putative seven transmembrane-spanning receptors that couple ..

..The current observations suggest that pharmacological intervention of cPLA(2) could be a novel therapeutic approach to acute lung injury caused by sepsis syndrome...

..The results presented in this study further suggest that our model is a good representative of human allergic rhinitis and offer evidence that CysLTs are chemical mediators mainly responsible for allergic nasal symptoms...

..Several studies have shown that leukotrienes may play a significant role in pathomechanisms of inflammatory diseases of human airways, skin, digestive tract and heart...

..Activation of leukotriene pathways is accompanied by rises in detectable urinary levels of leukotriene E4 (LTE4)...

..These data suggest membrane-bound dipeptidase deficiency, a new defect in leukotriene biosynthesis on the step of LTE(4) synthesis, as underlying defect...

..Urinary leukotriene E4 and leukotriene B4 glucuronide concentrations in 13 normal healthy adults were 94...

..Urinary leukotriene E4 concentration (LTE4), that reflects the whole body production of cysteinil-leukotrienes, is particularly ..

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..05). Mizolastine significantly reduced serum LTB4 and IFN-gamma levels as well as skin lesion LTB4, LTC4, LTE4 concentrations. LTs are involved in the pathogenesis of eczema. Mizolastine clearly reduces LTs levels in skin lesion...

..Although the synthesis of leukotrienes is not affected by corticosteroid treatment, the influence of corticosteroids on the leukotriene pathway remains unresolved...

..Use of leukotriene receptor antagonists improves disease control in children and adults with asthma. However, the relationship between cysteinyl leukotriene levels and indices of daily asthma control has not been studied directly...

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..The serum levels before and after treatment of eosinophilic cationic protein (ECP), leukotriene E4 (LTE(4)), and malondialdehyde (MDA) were determined...

..Monocytes/macrophages have a cysteinyl leukotriene 1 (CysLT1) receptor, but its function is poorly understood. Objective To elucidate the biological function of the CysLT1 receptor of human monocytes/macrophages...

..nocturnal awakenings, percentage of days and percentage of patients with asthma exacerbations, and urinary leukotriene E4 levels. These beneficial effects were similar to those produced by inhaled corticosteroids...

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..Eosinophil peroxidase and myeloperoxidase halogenate tyrosine residues in plasma proteins and generate 3-bromotyrosine (BY) and 3-chlorotyrosine (CY), respectively...

..Further research needs and new areas for leukotriene involvement in respiratory diseases are also discussed...

..Further experimental and clinical studies are needed to determine the potential of therapeutic strategies targeting the leukotriene pathway in cardiovascular disease...

Aspirin challenge of aspirin-intolerant asthma (AIA) patients causes a significant increase in leukotriene E4 (LTE4) concentration in urine. However, knowledge on leukotriene B4 (LTB4) generation in patients with AIA is insufficient...

..CONCLUSION: Persistent LTE 4 -induced airway eosinophilia may form the basis of an amplification mechanism for further eosinophil recruitment. Zafirlukast prevents LTE 4 -induced eosinophilic airway inflammation in mild asthma...

..This can be detected by means of the CAST assay. We assessed the positivity criteria and the reliability of antigen-specific sulfidoleukotriene production (CAST) in the in vitro diagnosis of betalactam (BL) allergic patients...

..To ensure the suitable preservation of isolated lungs, a super-cooling system was used to cool water to temperatures as low as -5 degrees C without freezing...

..Moreover, the interconversion between LTC4 and LTD4 and the metabolism into LTE4 may represent a major modulatory mechanism in the guinea-pig trachea by deciding which CysLT receptor is activated by the cysteinyl-leukotrienes...

..Studies of LTs in the cerebrospinal fluid (CSF) revealed different results mainly because of analytical difficulties...

..METHODS: Urinary concentrations of leukotriene E4 (LTE4), 11-dehydrothromboxane B2, 9alpha,11beta-prostaglandin F2, and Ntau-methylhistamine were measured ..

..We conclude that heparin inhibits hyperventilation-induced late-phase changes in peripheral airway function, and does so in part via the inhibition of eosinophil migration and eicosanoid mediator production and release...

..before and after therapy and concentrations of eosinophil cationic protein (ECP), prostaglandin E2 (PGE2), and leukotriene E4 (LTE4) were measured. RESULTS: A significant improvement in PEFR was found after zafirlukast therapy (p = 0...

..Leukotrienes (LTs) are important in asthma, and LT modifiers modulate antigen-induced asthma. Overproduction of LT by suppression of cyclooxygenase activity is involved in patients with aspirin-intolerant asthma (AIA)...

..Furthermore, the discovery of the high 15-lipoxygenase-1 activity in L1236 cells demonstrates that this cell line comprises a useful model system to study the chemical and biological roles of 15-lipoxygenase-1...

..CONCLUSIONS: Hyperventilation during exercise may not be the cause leading to EIA, neither did the activation of T lymphocytes, IL-4 and IL-5 gene expression nor ECP. Leukotriene may play an important role in the pathogenesis of EIA...

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..Altogether, these studies indicate that SCF-induced airway hyperreactivity is dependent upon leukotriene-mediated pathways...

..These results suggest that leukotriene E(4) solely activates a CysLT(1) receptor, and that the CysLT(1) receptor antagonist-resistant contraction to leukotriene D(4) and C(4) is mediated via another CysLT receptor...

..04 nM and 1030 +/- 180 fmol/mg, respectively. In competition studies, LTD4, stereoisomer (5R,6S)-LTD4, and leukotriene E4 (LTE4) competed with [3H]ICI-198615 binding to specific sites, with a stereoselectivity and a rank order of ..

..The current study was conducted to determine the effects of these combined ingredients upon the nasal response to allergen challenge in patients with seasonal allergic rhinitis...

..initial hepatobiliary secretion of 887 +/- 206 pmol kg-1 h-1 of the endogenous leukotriene metabolite N-acetyl leukotriene E4 (LTE4NAc). 4...

..excess unlabeled leukotriene C4, but not with excess unlabeled leukotriene A4, leukotriene B4, leukotriene D4, leukotriene E4, prostaglandin (PG) E1, PGF2a, or PGI2...

..However, the leukotriene E4 analogue BAY u9773 (6(R)-(4'-carboxyphenylthio)-5(S)-hydroxy-7(E),9(E),11(Z), 14(Z)-eicosatetraenoic acid) has ..

..The effects of aspirin- and allergen-induced bronchoconstriction on leukotriene levels in saliva and ex vivo stimulated blood were also compared with the effects of the provocations on urinary mediators...

..Results suggest that DPTL blocks platelet aggregation, vasoconstriction, and angiogenesis through binding to distinct eicosanoids involved in inflammation...

..U75302 (6-(6-(3-hydroxy-1E,5Z-undecadienyl)-2-pyridinyl)-1,5-hexane diol) >> leukotriene C4 = leukotriene D4 = leukotriene E4. For the human receptor the rank order of 12(S)-HETE, 20-COOH-leukotriene B4 and U75302 was reversed...

..In the present study we examined whether blocking leukotrienes might alleviate symptoms of dysmenorrhea in adolescents...

..D4 evoked contractile responses, leukotriene C4 being significantly more potent than leukotriene D4, whereas leukotriene E4 failed to elicit contractions...

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..These polar metabolites were determined to be 18-carboxy-19,20-dinor-leukotriene E4, 20-carboxy-leukotriene E4, and 20-hydroxy-leukotriene E4...

..The results will define the involvement of second messengers in the interactions between visual cells and retinal pigment epithelium during photoreceptor renewal...

..Similar enzymes catalyze conversion of leukotriene A4 to leukotriene E4. It is not known whether the enzymes responsible for the metabolism of xenobiotics and the endogenous ..

..e., parenchymal cells biliary epithelium) and effector cells (i.e., PMNs, Kupffer cells) that contribute to hepatotoxicity...

..The findings are expected to have immediate implications for asthma pathophysiology and treatment. ..

..Urine leukotriene E4 levels will be collected from each child on 16 consecutive schooldays and exhaled nitric oxide will be sampled ..

..abstract_text> ..

..Based on these findings, an application for an Interdisciplinary Center for Research on Blinding Eye Diseases will be prepared. ..

..The candidate will complement these studies with a curriculum of advanced training in methods for the design and analysis of gene expression studies in human subjects. ..

..The ultimate goal of these cell culture studies is to identify new therapies for asthma. (End of Abstract) ..

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..The ultimate goal of these cell culture studies is to identify new therapies for asthma. (End of Abstract) ..

..Study of the signaling pathways that stimulate conjunctival goblet cell proliferation will lead to the development of treatments to replenish the mucin layer in these diseases. ..

..This will provide significant insights into developing novel treatments for ocular surface inflammation. ..

..There is no cure for dry eye and as the lacrimal gland is the primary contributor to the aqueous layer of the tear film, replacement of a diseased lacrimal gland using stem cells would improve the health of the ocular surface. ..

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..lmmunofluorescence microscopy, Western and Northern blot analysis, and RT-PCR will be used to determine how the expression and release of EGF and its family members is regulated. ..

..Support is again requested for eight postdoctoral trainees having either a M.D. or Ph.D. degree or both and one predoctoral trainee. ..

..These studies may provide important information concerning the mechanisms of post- RSV childhood asthma. ..

..NIH support for this meeting will allow more graduate student and postdoctoral participation in.this exciting multidisciplinary meeting. ..