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We have studied a 50-year-old white man with chronic urticaria and angioedema who has responded to treatment with cimetidine alone for over 2 yr. In a double-blind, placebo-controlled study, cimetidine alone was at least as effective as chlorpheniramine in relief of urticaria and angioedema. Additionally, cimetidine significantly inhibited (p less than 0.01) the wheal response to histamine when it was compared to placebo. The inhibition of wheal response to histamine by cimetidine was significantly higher (p less than 0.05) than chlorpheniramine. The presence of predominantly H2- rather than H1-histamine receptors in the cutaneous blood vessels may be responsible for the therapeutic effects of cimetidine in this patient.

Human mononuclear cells (MNC) secrete histamine-releasing factor(s) (HRF) when cultured in vitro. HRF induces the release of histamine and other mediators from basophils and mast cells. We have shown that MNC also produced a histamine release inhibitory factor (HRIF), and that the synthesis is augmented by culture with physiologic concentrations of histamine (10(-10) to 10(-6) M) and by the mitogen concanavalin A (Con A). HRIF does not affect release initiated by other secretagogues such as allergen, anti-IgE, C5a, Con A, and phorbol myristate acetate. HRIF requires a preincubation with the cells for 5-10 min for maximal inhibition, and this effect is not abolished by washing the cells after the preincubation. The biological activity of HRIF is protease-sensitive, neuraminidase-resistant, and relatively heat-stable. HRIF can be distinguished from HRF by a lower apparent molecular mass (8,000-10,000 D).

We have recently described a specific antagonist of histamine-releasing factors that inhibits histamine release from basophils and mast cells. This histamine release inhibitory factor (HRIF) is produced by PBMC upon stimulation with histamine as well as mitogens such as Con A. The objective of this study was to investigate the cellular origin of HRIF produced by PBMC. Monocytes, T cells, and B cells were isolated to 96 to 99% purity by a combination of plastic adherence, E rosetting, and negative selection with mAb (OKM1, OKT11, OKB7, OKT4, and OKT8) and C. Purified subpopulations were cultured with histamine or Con A and then the processed supernatants were assayed for the inhibition of HRF-induced histamine release from basophils. The results of this study suggest that the highest amount of HRIF is synthesized by B cells followed by T cells and monocytes. The B cell origin of HRIF was confirmed by abolishing the activity after incubation of the cells with OKB7 mAb and C. Both CD4- and CD8- T cells are capable of producing HRIF. In mixing experiments, the synthesis of HRIF by two different subpopulations has been less than additive. T + B cells produced most of the HRIF activity. Monocytes tended to suppress the synthesis of HRIF by B cells. The synthesis of HRIF by so many cell types suggests that a fine balance between HRIF and HRF may regulate the mediator release from basophils and mast cells.

A drug formulary comprising 249 preparations of 132 drugs and drug combinations was prepared by the partners in a three-doctor general practice serving more than 5000 patients. No attempt was made to change to generic prescribing nor were repeat prescription drugs altered. Introduction of the formulary in September 1981 was followed by an increase in the proportion of prescriptions containing drugs from the formulary from about 55% to more than 60% for both repeat and non-repeat prescriptions. The proportion of formulary drugs on non-repeat prescriptions reached a maximum of 78% within the first year with the additional influence of information feedback. Over the first year the level of formulary drugs used for both repeat and nonrepeat prescribing levelled off at about 62%. Even with these modest changes, when compared with the costs of general practice prescribing in Scotland as a whole, the introduction of the formulary resulted in savings of approximately 10% within the practice for the mean ingredient costs both per patient and per prescription.

Rubidium-strontium isotopic analyses of whole-rock samples and of constituent minerals from a suite of rocks taken across the Grenville Front demonstrate that granitic rocks of the Superior province, with a primary age of approximately 2.4 billion years, and older metasedimentary rocks were reconstituted during Grenville metamorphism, at approximately 930 million years, and now form part of the Grenville province.

9-beta-d-Arabinofuranosyladenine (Ara-A) effectively inhibited the production of infectious vesicular stomatitis virus (VSV) in MDBK cells. Furthermore, inhibition was shown to begin as early as the first 3 hr of infection. Studies employing (3)H-l-leucine indicated that Ara-A did not affect protein synthesis in uninfected cells, although it did cause a marked stimulation of protein synthesis in VSV-infected cells during the log phase of the growth cycle. Puromycin, an inhibitor of protein synthesis, was a more effective viral inhibitor than Ara-A. However, the combination of Ara-A and puromycin was less effective than puromycin alone except when present for long time periods. Short-term labeling experiments with (3)H-uridine demonstrated that Ara-A depressed ribonucleic acid (RNA) synthesis in uninfected cells, whereas periods of stimulation and depression of radioisotope incorporation occurred in infected cells. The results support the notion that Ara-A is incorporated into RNA early during viral replication.