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R Eady

Publications and source records attributed to R Eady.

7 recordsLinked to original sources
PubMed1993

The immunopharmacological actions of nedocromil sodium relative to the use of its 2% ophthalmic solution.

The immunopharmacological actions of nedocromil sodium are fully compatible with administration to man. Nedocromil sodium exhibits a wide range of anti-inflammatory actions. When compared with sodium cromoglycate, nedocromil sodium is more potent and a major difference is seen in the Ascaris-sensitised monkey subjected to bronchial challenge with specific antigen. In this model of chronic airway disease nedocromil sodium provides significant protection against changes in airway resistance and lung compliance provoked by antigen challenge. Sodium cromoglycate does not. This difference is most readily explicable by the greatly enhanced effect of nedocromil sodium, relative to that of sodium cromoglycate, in preventing the release of mediators such as histamine, leukotriene C4 and prostaglandin D2 from the cellular population of the chronically inflamed bronchus, especially from mast cells of the mucosal type. There is growing evidence that these mediators are important in allergic diseases of the eye and this additional activity may be expected to give nedocromil sodium extended scope in the management of conjunctivitis in which allergic inflammation and hyperresponsiveness are significant pathophysiological factors.

Animals↗
PubMed1987

Binding of ADP and orthophosphate during the ATPase reaction of nitrogenase.

The pre-steady-state ATPase activity of nitrogenase from Azotobacter vinelandii was investigated. By using a rapid-quench technique, it has been demonstrated that with the oxidized nitrogenase complex the same burst reaction of MgATP hydrolysis occurs as observed with the reduced complex, namely 6-8 mol orthophosphate released/mol MoFe protein. It is concluded that the pre-steady-state ATPase activity is independent of electron transfer from Fe protein to MoFe protein. Results obtained from gel centrifugation experiments showed that during the steady state of reductant-independent ATP hydrolysis there is a slow dissociation of one molecule of MgADP from the nitrogenase proteins (koff less than or equal to 0.2 s-1); the second MgADP molecule dissociates much faster (koff greater than or equal to 0.6 s-1). Under the same conditions orthophosphate was found to be associated with the nitrogenase proteins. The rate of dissociation of orthophosphate from the nitrogenase complex, as estimated from the gel centrifugation experiments, is in the same order of magnitude as the steady-state turnover rate of the reductant-independent ATPase activity (0.6 mol Pi formed X s-1 X mol Av2(-1) at 22 degrees C). These data are consistent with dissociation of orthophosphate or MgADP being rate-limiting during nitrogenase-catalyzed reductant-independent ATP hydrolysis.

Adenosine Diphosphate↗