Establishment of allergic dermatitis in NC/Nga mice as a model for severe atopic dermatitis.

Mite antigen has been suggested to play important roles in the onset and/or development of atopic dermatitis, and mite antigen-induced dermatitis models appear beneficial for the basic study of atopic dermatitis. In the present study therefore, we attempted to establish an allergic dermatitis model in mice using Dermatophagoides farinae crude extract as an antigen. Mite antigen solution at a concentration of 1 or 10 mg/ml was painted 5 times repeatedly at an interval of 7 d onto the ear of NC/Nga or BALB/c mice with or without simultaneous tape-stripping. Apparent biphasic ear swelling was observed after the 4th and 5th antigen applications in both strains of mice treated with 10 mg/ml of antigen solution. Thickening of the epidermis, fibrosis of the dermis, and the accumulation of inflammatory cells were also observed after the 5th application. The inflammatory changes were more evident in NC/Nga mice than in BALB/c mice and potentiated by tape-stripping. The ear swelling was accompanied by increased serum IgE, increased expression of interleukin-4 mRNA and decreased expression of interferon-gamma mRNA in cervical lymph nodes and ears. These results indicate that ear swelling caused by repeated mite antigen application with simultaneous tape-stripping has a Th2-dominant background and that the inflammatory responses are expressed more potently in NC/Nga mice than in BALB/c mice. The dermatitis caused by mite antigen in NC/Nga mice appears to be a useful model for the basic study of atopic dermatitis.

Five-year angiographic outcome in patients without restenosis following coronary balloon angioplasty: a comparison between non diabetic and diabetic lesions.

Few studies have investigated the long-term angiographic outcome of successful coronary balloon angioplasty (CBA) among diabetic and nondiabetic dilated lesions. The purpose of this study was to evaluate and compare the long-term (>5 years) outcomes of diabetic and nondiabetic CBA lesions which had remained patent 3-12 months after intervention. Twenty-five patients (45 lesions) with diabetes mellitus and 79 patients (138 lesions) without diabetes mellitus were enrolled as subjects. All patients who underwent CBA without restenosis within 3-12 months of the initial CBA based on follow-up angiographic evaluation were included. Quantitative coronary angiograms performed before, immediately after CBA, during the 3-12-month period (mean 4.1 +/- 1.0 months), and at or after 5 years (mean 6.4 +/- 2.0 years) were compared. There was no significant difference in the reference diameter between nondiabetic and diabetic lesions at any of the four time points studied. The minimum lumen diameter before and immediately after the procedure and at the 3-12-month follow-up did not differ significantly between the two groups. At >5-year follow-up. the minimum lumen diameter was significantly (P = 0.005) decreased in diabetic lesions. Total occlusion occurred in 9% (4/45) of the diabetic lesions compared to only 1%, (1/138) in the nondiabetic lesions (P = 0.007). Diabetic lesions showed significant (P = 0.049) narrowing between the 3-12 month period and >5-year follow-up. Fifty-one percent (18/35) of the nondiseased vessels in the diabetic patients at the time of enrollment had new stenosis during the follow-up periods. In conclusion, compared to nondiabetic lesions, patients with diabetic lesions who underwent CBA were more predisposed to have stenotic progression and total occlusion.

Involvement of unique mechanisms in the induction of scratching behavior in BALB/c mice by compound 48/80.

Compound 48/80 induced scratching behavior in BALB/c mice, and the role of mast cell mediators in this behavior was examined. Mouse scratching behavior was detected and evaluated using a new apparatus, MicroAct. Compound 48/80 increased the incidence of scratching behavior and scratching time in a dose-dependent manner, accompanied by a potent activation of mast cells and a potent increase in vascular permeability. Dibucaine and mu-opioid receptor antagonists inhibited the scratching behavior. Although histamine H(1) receptor antagonists potently inhibited the vascular permeability increase, they did not affect the scratching behavior. Methysergide inhibited the scratching behavior slightly without affecting the vascular permeability increase, whereas cyproheptadine inhibited both. A cyclooxygenase inhibitor, a 5-lipoxygenase-activating protein inhibitor and a PAF receptor antagonist did not affect the scratching behavior. High doses of serotonin induced scratching behavior less frequently than did compound 48/80. Furthermore, mast cell-deficient WBB6F1-W/W(v) mice exhibited frequent scratching behavior after injection of compound 48/80. These results clearly indicate that compound 48/80 can induce scratching behavior in mice independent of mast cell mediators.