Search

The effect of specific antigen challenge on the lung function of eight allergic asthmatic patients after placebo and indomethacin pretreatment has been investigated. Plasma levels of thromboxane B2(TxB2), metabolite of thromboxane A2, 6-keto-PGF1 alpha, metabolite of epoprostenol, (prostacyclin, PGI2) and beta-thromboglobulin (beta TBG) following antigen challenge in these eight patients have also been measured after placebo and indomethacin pretreatment. Each patient underwent two antigen inhalations 1 week apart. One challenge took place after 4 days pretreatment with indomethacin capsules 25 mg four times daily, and the other took place following 4 days placebo pretreatment, one matched capsule four times daily. The order of administration was random but balanced and blind with respect to the patient. Following placebo pretreatment two patients presented with an early antigen response only, four presented with a biphasic antigen response and two presented with a delayed antigen response only. The asthmatic response for each patient was consistent on re-exposure. Indomethacin pretreatment suppressed the delayed antigen induced asthmatic response. This suppression was reproducible. There was a rise in plasma TxB2 levels on antigen challenge following placebo pretreatment but not following indomethacin pretreatment, whereas there was a rise in 6-keto-PGF1 alpha after antigen challenge following indomethacin but not placebo pretreatment. No significant change in plasma beta TBG or platelet counts from control values was observed following antigen challenge with either placebo or indomethacin pretreatment. It is suggested that the production of PGI2 and suppression of TxA2 by indomethacin pretreatment contribute to the suppression of the delayed antigen induced asthmatic response and that platelets play a minimal role in this process. [ABSTRACT FROM AUTHOR]

The therapeutic potential of non-steroid anti-inflammatory drugs in clinical asthma is offset by the real possibility of hypenensitivity and inducton of severe airways obstruction. The influence of indomethacin on the antigen-induced asthmatic response was tested. Early and delayed asthmatic responses were recorded after antigen challenge in 13 subjects. Indomethacin pretreatment totally or partially inhibited the delayed asthmatic response in 10 of 11 subjects. Inhibition by indomethacin of products of the arachidonic cascade which participate in the pathogenesis of the delayed asthmatic response could explain this phenomenon. A similar therapeutic response was documented without adverse drug reactions when five subjects were restudied after several months. In the same group the early asthmatic response was suppressed in six, enhanced in two and unchanged in four of 12 subjects. This variable response indicates that spasmogenic prostaglandin breakdown products may be important for certain individuals, but are generally of less importance in the early asthmatic response. Clinical trials with indomethacin as a steroid saving agent in allergic asthma appear feasible and can be conducted safely. [ABSTRACT FROM AUTHOR]

Gamma rays of energy 9.404 and 9.700 MeV were obtained from the reactionNe( p, γ)Na at proton energies of 640 and 950 keV respectively and were resonantly absorbed in sodium metal. Isotopically separatedNe targets on nickel backings were used. The following level widths forNa were obtained: The 9.404 MeV level: Γ=65 ±40eV Γ=2.2±0.7eV. The 9.700 MeV level: Γ=9.5 Γ=5.6. The disagreement between the results for the 9.404 MeV level and the previously determined values can probably be ascribed to proton scattering in the window of the gas target used in the latter measurement. [ABSTRACT FROM AUTHOR]

The gamma decay of theNe( p, y)Na resonances in the proton energy range E=1.0→2.0 MeV has been investigated with a 20cm Ge(Li) detector. Implanted targets were used. The absolute strengths of the strongest resonances were determined and the branching ratios of twenty resonance levels and several bound states are reported. Mean lifetimes of the levels at E=2.078 MeV (18.7±3.5 fs), 2.393 MeV (580 fs), 2.641 MeV (88 fs), 2.985 MeV (4.0 fs), 3.679 MeV (24 fs), 3.915 MeV (7.4 fs) and 4.775 MeV (<2.0 fs) were obtained from measurements of the gamma ray Doppler shifts. [ABSTRACT FROM AUTHOR]

The yield curve and resonance strengths of resonances in theMg( p, γ)Al reaction for the proton energy range E=800 keV to E=1,830 keV, have been determined and the existence of a resonance at E=1.184 MeV confirmed. Single energy spectra as well as decay schemes and branching ratios are given for these resonances. An upper level of 2.0×10 sec for the lifetime of the 3.079 MeV level inAl results from a Doppler shift attenuation measurement carried out on the 2.624 MeV gamma line originating in the 3.070 MeV→0.455 MeV transition inAl. [ABSTRACT FROM AUTHOR]