Background: Although there is increasing evidence of the importance of cysteinyl leukotrienes (LT) as mediators of aspirin‐induced bronchoconstriction in aspirin‐sensitive asthma, the cellular origin of the LT is not yet clear. Methods: Urinary concentrations of leukotriene E4 (LTE4), 11‐dehydrothromboxane B2, 9α,11β‐prostaglandin F2, and Nτ‐methylhistamine were measured during the 24 h following cumulative intravenous administration of increasing doses of lysine aspirin to asthmatic patients. In addition, the urinary concentrations of these metabolites were measured on 5 consecutive days in a patient who suffered an asthma attack after percutaneous administration of nonsteroidal anti‐inflammatory drugs. Results: In aspirin‐induced asthma patients (AIA, n=10), the basal concentration of urinary LTE4, but not the other metabolites, was significantly higher than that in aspirin‐tolerant asthma patients (ATA, n=10). After intravenous aspirin provocation, the AIA group showed a 13.1‐fold (geometric mean) increase in excretion of LTE4 during the first 3 h, and 9α,11β‐prostaglandin F2 also increased in the AIA group during the first 0–3 h and the 3–6 h collection period. Nτ‐methylhistamine excretion was also increased, but to a lesser degree. Adminis‐tration of aspirin caused significant suppression of 11‐dehydrothromboxane B2 excretion in both the AIA and ATA groups. When the percentage of maximum increase of each metabolite from the baseline concentrations was compared between the AIA group and the ATA group, a significantly higher increase in excretion of LTE4, 9α,11β‐prostaglandin F2, and Nτ‐methylhistamine was observed in the AIA group than the ATA group. An increased excretion of LTE4 and 9α,11β‐prostaglandin F2 has been detected in a patient who suffered an asthma attack after percutaneous administration of nonsteroidal anti‐inflammatory drugs. Conclusions: Considering that human lung mast cells are capable of producing LTC4, prostaglandin D2, and histamine, our present results support the concept that mast cells, at least, may participate in the development of aspirin‐induced asthma.

In the isolated papillary muscle of the rabbit the time course of the effects of selective beta- and alpha-adrenoceptor stimulation by isoprenaline and methoxamine, respectively, on the contractile force and on the level of 3',5'-cyclic AMP (cAMP) was determined. 1. Isoprenaline (3 times 10(-7) M) increased significantly the content of cAMP at 15 sec and elevated it to the maximal level-about twice the control value-at 30 sec after its administration, while the developed tension of the papillary muscle was also increased significantly at 15 sec and reached gradually its maximum at 90 sec. 2. Compared with isoprenaline methoxamine (10(-4) M) increased the developed tension very slowly: the maximal response was reached after 20 min. The level of cAMP, on the other hand, was changed neither before nor during the induction of the positive inotropic effect of methoxamine. 3. The phosphodiesterase inhibitor papaverine (10(-5) M) inhibited the PDE activity of the papillary muscle by about 40% after an incubation of 1 hr, and increased the level of cAMP significantly. The effects of isoprenaline on the contractile forced and on the level of cAMP were considerably enhanced by papaverine: the content of cAMP was increased by isoprenaline (3 times 10(-7) M) to about 3 times the control value and also its positive inotropic effect was significantly greater than in controls without papaverine. On the other hand, the positive inotropic effect of methoxamine (10(-4) M) was not affected by papaverine (10(-5) M). Furthermore, in the papillary muscle treated with papaverine the level of cAMP was significantly reduced by methoxamine: the papaverine-induced increase of cAMP was abolished by methoxamine. 4. The present results are compatible with the hypothesis that cAMP is involved as a mediator in the positive inotropic effect induced by beta-adrenoceptor stimulation, and indicate further that the stimulation of alpha-adrenoceptors evokes its positive inotropic effec through a mechanism other than that elicited by beta-adrenoceptor stimulation, i.e., independent of cAMP.

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We report a case of pulmonary nocardiosis in a 69-year-old man with rheumatoid arthritis who was receiving corticosteroid treatment. The patient received prednisolone for rheumatoid arthritis and antibiotics for his fever and pneumonia in another hospital, but the response to the therapy was poor. After admission to our hospital, he improved following treatment with imipenem/cilastatin for Nocardia asteroides. Pulmonary nocardiosis is difficult to diagnose and should be considered in the differential diagnosis, especially in an immunocompromised host.

Using cine magnetic resonance imaging (MRI) and echocardiography, we investigated the effects of candesartan cilexetil, a specific angiotensin II type 1 (AT1) receptor antagonist, on left ventricular (LV) mass and hemodynamics in patients with essential hypertension. Ten patients (four men and six women) with essential hypertension received candesartan cilexetil 2-8 mg/day orally for 8-12 weeks. After drug administration, systolic blood pressure (BP) decreased from 178.9 +/- 17.2 mmHg (mean +/- SD) to 150.2 +/- 14.3 mmHg (P < 0.0001) and diastolic BP from 101.4 +/- 6.5 mmHg to 87.8 +/- 11.9 mmHg (P = 0.0021). Both MRI and echocardiography revealed a significant decrease in LV mass index (LVMI) after candesartan cilexetil. MRI indicated that LVMI decreased from 111.3 +/- 31.3 g/m2 to 102.6 +/- 32.1 g/m2 (P = 0.0484) and echocardiography that LVMI decreased from 123.9 +/- 31.1 g/m2 to 115.8 +/- 31.4 g/m2 (P = 0.0316). Total systemic vascular resistance decreased significantly during treatment with candesartan cilexetil in both MRI and echocardiography assessment, from 1847.2 +/- 636.3 dynes.s.cm-5 to 1540.4 +/- 432.0 dynes.s.cm-5 (P = 0.0034) on MRI and from 1820.4 +/- 318.8 dynes.s.cm-5 to 1659.0 +/- 317.7 dynes.s.cm-5 (P = 0.0060) on echocardiography. These findings suggest that candesartan cilexetil 2-8 mg/day orally for 8-12 weeks is beneficial in the regression of cardiac hypertrophy in patients with essential hypertension.