Double-blind comparison of terfenadine, chlorpheniramine, and placebo in the treatment of chronic idiopathic urticaria

The efficacy of terfenadine, a nonsedating H1 antihistamine, in the management of chronic idiopathic urticaria was compared with chlorpheniramine and placebo in a parallel multicenter trial. Subjects with symptoms of hives for 3 days per week for at least 6 weeks were initially screened and admitted if no identifiable cause for symptoms could be determined. Patients entered a single-blind placebo period, and if hives of moderate severity were present for at least 3 days during the week, they were randomly assigned in a double-blind fashion to take terfenadine, 60 mg twice daily, chlorpheniramine, 4 mg three times a day, or placebo for 6 weeks. Data were analyzed for 122 patients. Those patients receiving both active treatments noted significant improvement in symptoms: pruritus, redness, number of hives, and waking hours during which hives were present, at the end of the first day of therapy. Symptom control by terfenadine was statistically superior to placebo during all 6 weeks, as rated by both patients and investigators. However, statistical significance was not achieved for chlorpheniramine at all observation points. Diphenhydramine was permitted as a relief medication for refractory symptoms and was taken by 52% of subjects receiving placebo, 26% taking chlorpheniramine, and only 9% of patients who were receiving terfenadine. In addition to providing superior symptom control, terfenadine caused less drowsiness and fatigue than chlorpheniramine. Terfenadine is a useful therapeutic agent for primary management of chronic idiopathic urticaria.

Induction of an immature T-cell phenotype in malignant helper T cells by cocultivation with epidermal cell cultures

The possible inductive effect of epidermal cells on T-cell maturation has been examined employing an in vitro cocultivation technique. Mononuclear cells from 6 patients with cutaneous T-cell lymphoma (CTCL) and from 12 healthy volunteers were studied. In the 6 CTCL patients, all showed an expansion of the helper T-cell subpopulation and in one patient with leukemic CTCL, there was almost complete replacement of peripheral blood mononuclear cells by malignant cells with a helper T-cell phenotype. Epidermal cells derived from normal human skin were cultured to confluent monolayers, and were cocultivated with the mononuclear cells from CTCL patients or normal controls for 48 h at a density of 10(6)/ml. Following cocultivation, the surface phenotype of the cells from the 12 healthy volunteers and 5 of the patients with CTCL showed no significant phenotypic change. In the patient with leukemic CTCL, however, the surface phenotype of the malignant T cells had changed, with the acquisition of the T6 antigen by the majority of the cells. Cells cocultivated in medium alone and with human fibroblast monolayers showed no change in surface phenotype. The malignant T cells from the leukemic CTCL patient failed to react in a mixed lymphocyte culture to lymphocytes from 2 different healthy donors, and showed no phenotypic change following culture with these lymphocytes, indicating that the phenotypic change seen was not due to allogeneic stimulation.

The repair of psoralen monoadducts by the Escherichia coli UvrABC endonuclease

We have examined the interactions of UvrABC endonuclease with DNA containing the monoadducts of 8-methoxypsoralen (8-MOP) and 4,5',8-trimethylpsoralen (TMP). The UvrA and UvrB proteins were found to form a stable complex on DNA that contains the psoralen monoadducts. Subsequent binding of UvrC protein to this complex activates the UvrABC endonuclease activity. As in the case of incision at pyrimidine dimers, a stable protein-DNA complex was observed after the incision events. For both 8-MOP and TMP, the UvrABC endonuclease incised the monoadduct-containing strand of DNA on the two sides of the monoadduct with 12 bases included between the two cuts. One incision was at the 8th phosphodiester bond on the 5' side of the modified base. The other incision was at the 5th phosphodiester bond 3' to the modified base. The UvrABC endonuclease incision data revealed that the reactivity of psoralens is 5'TpA greater than 5'ApT greater than 5'TpG.

The Identification of Rubber Compounding Ingredients by Using Thin Layer Chromatography

TLC is a quick, easy method to the identification of rubber compounding ingredients. Both silica gel absorbent and C18 absorbent are suitable for these identifications. With the mobile phases used in this study, a better separation of antioxidants is possible using silica gel absorbent. Work should be continued on finding suitable mobile phases for the C18 absorbent, since the Rf values are more reproducible. For those separations that require a separation of compounds of varying molecular weight, the C18 absorbent is superior to silica gel absorbent. The visualization systems that have been developed for use with silica gel absorbent are suitable for use with C18 absorbent. These systems give the same colors for either absorbent.