Attenuating effect of H+K+ATPase inhibitors on airway cough hypersensitivity induced by allergic airway inflammation in guinea-pigs.

BACKGROUND: Gastrooesophageal reflux (GER) is a frequent cause of chronic cough. Several investigators have indicated that inhibitors of H(+)K(+)ATPase (proton pump inhibitors; PPIs) could relieve coughing via inhibition of acid reflux. However, we considered that PPIs might directly inhibit increased cough reflex sensitivity. OBJECTIVE: The present study was designed to examine whether PPIs directly inhibit antigen-induced increase in cough reflex sensitivity and to elucidate the mechanism. METHODS: Actively sensitized guinea-pigs were challenged with aerosol antigen (ovalbumin, OVA) and cough reflex sensitivity to inhaled capsaicin was measured 24 h later. The PPIs (omeprazole and rabeprazole) or the histamine H(2) blocker cimetidine were administered intraperitoneally 1 h before OVA challenge and before measuring cough reflex sensitivity, then bronchoalveolar lavage fluid (BALF) was immediately collected. The pH of the fluid obtained by bronchial washing was determined after examining the effect of rabeprazole on the cough response to capsaicin. RESULTS: The number of coughs elicited by capsaicin was significantly increased 24 h after challenge with OVA compared with saline, indicating antigen-induced increase in cough reflex sensitivity. Both PPIs dose dependently and significantly inhibited antigen-induced cough hypersensitivity. Omeprazole did not influence the antigen-induced increase in the total number of cells or ratio (%) of eosinophils in BALF. Cimetidine did not affect the antigen-induced cough hypersensitivity or cellular components of BALF. The pH of the bronchial washing fluid was significantly decreased in antigen-challenged animals. Rabeprazole did not affect the antigen-induced decrease in the pH of bronchial washing fluid. CONCLUSION: These findings show that PPIs, but not histamine H(2) blockers, can directly decrease antigen-induced cough reflex hypersensitivity, while the mechanism remains unclear.

Primary anorectal malignant melanoma: report of a case.

Primary anorectal malignant melanoma is a fairly uncommon but highly malignant disease. This disease is sometimes mistaken for such benign conditions as either a hemorrhoid or rectal polyp. We herein describe a case of early primary malignant melanoma of the anal canal. In this case, magnetic resonance (MR) imaging was found to be useful for diagnosing the melanotic melanoma. We especially emphasize the usefulness of a fat-saturation MR image in distinguishing melanotic melanoma from other rectal tumors.

[Evaluation of efficacy for Japanese cedar pollen-specific immunotherapy by lymphocyte proliferation test].

Peripheral mononuclear cells from 47 patients suffering from Japanese cedar pollinosis were stimulated with crude pollen extract of Cryptomeria Japonica (CJ) to evaluate the effect of CJ-specific immunotherapy. The stimulation index (SI) with crude pollen extract of CJ in the patients with excellent and good clinical outcome was significantly lower than those with poor outcome. The SI increased with the increasing symptoms in a dose dependent manner. In the patients under immunotherapy for long period, the good clinical outcome and low SI were gained. These results suggest that peripheral lymphocyte proliferation test should be a good objective indicator for allergen-specific immunotherapy.

Myricetin and quercetin, the flavonoid constituents of Ginkgo biloba extract, greatly reduce oxidative metabolism in both resting and Ca(2+)-loaded brain neurons.

The antioxidant action of myricetin and quercetin, the flavonoid constituents of the extract of Ginkgo biloba (EGb), on oxidative metabolism of brain neurons dissociated from the rats was examined using 2',7'-dichlorofluorescin (DCFH) which is retained within the neuron and then is oxidized by cellular hydrogen peroxide to be highly fluorescent. Incubation with myricetin or quercetin reduced the oxidation of DCFH in resting brain neurons, more profoundly than EGb. Myricetin decreased the oxidative metabolism at concentrations of 3 nM or more. It was 10 nM or more for the case of quercetin. Incubation with each flavonoid constituent also reduced the Ca(2+)-induced increase in the oxidative metabolism without affecting the cellular content of DCFH or the intracellular concentrations of Ca2+. Such an antioxidant action of myricetin or quercetin may be responsible for a part of the beneficial effects of EGb on brain neurons subject to ischemia.

Growth factor requirement for survival in cell-cycle dormancy of primitive murine lymphohematopoietic progenitors.

We used enriched marrow cells from mice administered three doses of 150 mg/kg 5-fluorouracil (5-FU) 1, 3 and 7 days before they were killed to study the effects of different growth factors on the survival of primitive, cell-cycle dormant progenitors in culture. This cell population yielded substantially fewer colonies in response to single growth factors than corresponding preparations from day 2 post-5-FU bone marrow samples, and the majority of progenitors were multipotential in nature. These observations were consistent with the prediction that multiple cycles of 5-FU treatment would further enrich for primitive cells. With this cell population, we found that among all the factors tested, interleukin-3 (IL-3) and steel factor (SF) as single factors are the most effective in supporting survival of dormant primitive progenitors. Interleukin-6 (IL-6), granulocyte colony-stimulating factor (G-CSF), interleukin-11 (IL-11), interleukin-4 (IL-4), interleukin-1 alpha (IL-1 alpha), and tumor necrosis factor-alpha (TNF-alpha) also supported survival of a few progenitors, but much less effectively than either IL-3 or SF. The hematopoietic progenitors that survived for 1 week in liquid culture supplemented with either IL-3 or SF retained the capability to develop pre-B-cell colonies in secondary culture. Our results demonstrate that survival of dormant murine lymphohematopoietic cells in culture is dependent on the presence of specific growth factors, and that this growth factor requirement can be satisfied well by SF or IL-3.