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Background and Purpose: The histamine H4 receptor is widely expressed in cells of immune origin and has been shown to play a role in a variety of inflammatory processes mediated by histamine. In this report, we describe the in vitro and in vivo anti-inflammatory properties of a potent histamine H4 receptor antagonist, A-940894 (4-piperazin-1-yl-6,7-dihydro-5H-benzo[6,7]cyclohepta[1,2-d]pyrimidin-2-ylamine)., Experimental Approach: We have analysed the pharmacological profile of A-940894 at mouse native, rat recombinant and human recombinant and native, histamine H4 receptors by radioligand binding, calcium mobilization, mast cell shape change, eosinophil chemotaxis assays and in the mouse model of zymosan-induced peritonitis., Key Results: A-940894 potently binds to both human and rat histamine H4 receptors and exhibits considerably lower affinity for the human histamine H1, H2 or H3 receptors. It potently blocked histamine-evoked calcium mobilization in the fluorometric imaging plate reader assays and inhibited histamine-induced shape change of mouse bone marrow-derived mast cells and chemotaxis of human eosinophils in vitro. In a mouse mast cell-dependent model of zymosan-induced peritonitis, A-940894 significantly blocked neutrophil influx and reduced intraperitoneal prostaglandin D2 levels. Finally, A-940894 has good pharmacokinetic properties, including half-life and oral bioavailability in rats and mice., Conclusions and Implications: These data suggest that A-940894 is a potent and selective histamine H4 receptor antagonist with pharmacokinetic properties suitable for long-term in vivo testing and could serve as a useful tool for the further characterization of histamine H4 receptor pharmacology.

Thirty-seven patients with widely metastatic malignant melanoma were treated with one of three chemotherapy regimens, incorporating high-dose dacarbazine (DTIC). The chemotherapy was followed by autologous bone marrow rescue which was harvested under local anesthesia in 25 of the patients. The three regimens comprised a 24-hour infusion of DTIC (Regimen A for patients less than 45 years of age, 4.3 to 10.5 g/m2; B, if greater than 45 years of age 2.7 to 4.0 g/m2; and later C, if greater than 45 years of age 7.0 to 8.0 g/m2). The second alkylating agent was given at +8 and +16 hours from the start of DTIC. The total doses of the melphalan ranged from 60 to 130 mg/m2 for Regimen A and 30 to 40 mg/m2 for Regimen B. Ifosfamide 5.0 to 8.0 g/m2 was given instead of melphalan in Regimen C. The response rates for the regimens were 81% (25% CR) for A, 27% (11% CR) for B, and 20% (with no complete responders) for Regimen C. There was no statistically significant difference between the three regimens for survival with a median value of 6 months. One of the 16 patients treated with the very high dose Regimen A died of septicemia and three of ten patients in Regimen C died within the first 2 weeks of treatment. There was statistically significant greater myelosuppression, stomatitis, and diarrhea in the very high dosage DTIC and melphalan (Regimen A) compared with the other two regimens. No significant difference in response rate or toxicity was observed for the different dosages escalated within each of the three regimens. Although hematologic and gastrointestinal toxicity were very severe, no unusual side effects were noted except for one episode of severe acute renal failure in the high-dose DTIC and melphalan, Regimen A. Responses occurred mainly in nonvisceral, nodal, and cutaneous sites and occasionally in pulmonary metastases. The Karnofsky performance improved 4 to 6 months after treatment notably with the high-dose DTIC and melphalan therapy. No survival benefit for the combination chemotherapy despite the high dosages was detected and such an approach currently cannot be recommended.

Questionnaire, Edwards-Kirkpatrick scale, and semantic differential techniques were used to provide converging measures of psychosocial factors affecting participation in a community self-help organization. This group is attempting to maintain the racially mixed residential character of a neighborhood located in a zone of transition between large tracts of project housing and an area of stores, apartment buildings, and offices on the edge of a southern center city. Results indicate that a complexly integrated set of attitudes toward the area as a place to live, one's neighbors as active and potent yet stable people, and the future as a promising and secure time of life seems to determine attitudes toward and participation in the community organization.