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A W Scott

Publications and source records attributed to A W Scott.

29 records · Page 2Linked to original sources

Typical antipsychotics exhibit inverse agonist activity at rat dopamine D1-like receptors expressed in Sf9 cells.

The baculovirus system has been used to express the rat dopamine D1 receptors in Spodoptera frugiperda (Sf9) cells. A panel of typical antipsychotics including, alpha-flupenthixol, fluphenazine and thioridizine were found to inhibit dopamine-dependent stimulation of adenylyl cyclase. However, these compounds were also found to inhibit adenylyl cyclase activity in the absence of agonist in Sf9 cells expressing dopamine D1-like receptors. Therefore, these nonselective dopamine receptor compounds displayed negative intrinsic or inverse agonist activity. None of the compounds tested were neutral antagonists.

Adenylyl Cyclases↗

Genetic polymorphisms at the rat and murine loci coding for dopamine D2-like receptors.

Southern blot hybridization techniques have been used to identify genetic polymorphisms at the D2, D3 and D4 dopamine receptor loci in mice and rats. Genomic DNA from a panel of outbred and inbred strains of rats and inbred strains of mice was digested with a variety of restriction endonucleases. After separation of the restriction digests on the basis of size using agarose gel electrophoresis, 32P-labeled DNA probes coding for the rat D2, D3 and D4 dopamine receptors were used to identify a series of genetic polymorphisms at each of these receptor loci. Genetic polymorphisms were found for the rat and murine D2, D3 and D4 dopamine receptor loci. It is anticipated that these genetic polymorphisms will be useful in pharmacogenetic studies to determine the influence of the D2-like receptors in reward and addictive behaviors.

Animals↗

Non-medicinal ingredients.

Many drug products contain excipients which perform important functions in terms of stability, solubility and identification. Excipients should not be considered as inactive ingredients, as they have been associated with a wide range of adverse reactions in some individuals. Monitoring for excipient toxicity is important. Equally important, is the provision of non-medicinal ingredient information on packaging, patient information leaflets and prescribing information, as most excipient-related toxicity is preventable when the formulation is known.

Animals↗

Sudden death in sport before and after introduction of the Basic Fitness Test.

This study examines sudden unexpected deaths in relation to strenuous exercise in the five years following the introduction of the Basic Fitness Test viz: 1978-82 and, by comparison with an identical study of the years 1968-77, shows that the annual exercise associated mortality rate rose from 3.5 per 100,000 before the Basic Fitness Test to 4.75 per 100,000 after its introduction. Sudden unexpected death in relation to strenuous exercise is rare, and its incidence has not importantly changed since the introduction of the Basic Fitness Test.

Adult↗

Antitumor activity of Propionibacterium acnes (Corynebacterium parvum) and isolated cytoplasmic fractions.

The tumor-inhibitory effect of an intralesional injection of Propionibacterium acnes was of limited duration ("finite"). Our model was the DBA/2 syngeneic mouse injected with P815 mastocytoma cells (5 X 10(5)) into each rear footpad; only the left was treated, leaving the right as a "pseudometastasis." The finite effect occurred at approximately 21 days after the first treatment. Subsequent i.p. treatments with P. acnes did not alter this effect, although they increased mean survival time. With one footpad tumor, we achieved 22% cures with complete regression and no sign of metastatic growth. A RNA fraction from P. acnes produced inhibition of tumor growth, but crude cell walls and cell walls treated with Pronase had no effect. A P. acnes cytoplasmic fraction with tumor-inhibitory activity was pelleted by high-speed centrifugation; this fraction inhibited P815 mastocytoma as fully as whole cells injected in one-fifth the dose on a nitrogen basis and did not cause a local inflammatory reaction. The activity of the pellet also differed from whole cells in that it was equally inhibitory to the pseudometastasis in the contralateral right rear footpad. The cytoplasmic fraction apparently contained at least two active components since activity was obtained at two dilution levels. Such activity was relatively stable at 5 degrees, but it was unstable at -30 degrees.

Animals↗

Mycobacterial ribonucleic acid: comparison with mycobacterial cell wall fractions for regression of murine tumor growth.

Mycobacterial ribonucleic acid (RNA) and cell wall skeleton fraction isolated from H37Ra caused P-815 mastocytoma regression in DBA/2 mice provided the animals were presensitized with freshly harvested living H37Ra cells. In the absence of presensitization, only the RNA fraction inhibited. Cell wall skeleton fraction, under these conditions, stimulated tumor growth. Cell wall lipids (from H37Ra) added to H37Ra cell wall skeleton fraction did not increase the inhibitory activity of cell wall skeleton fraction alone. Mycobacterial RNA appeared to be an effective inhibitor of P-815 mastocytoma metastases as shown by (i) the inhibition of a second footpad lesion distant from the one treated and (ii) increase in survival time.

Animals↗

Interferon production by inactivated Newcastle disease virus in cell cultures and in mice.

Youngner, Julius S. (University of Pittsburgh, Pittsburgh, Pa.), Anne W. Scott, Jules V. Hallum, and Warren R. Stinebring. Interferon production by inactivated Newcastle disease virus in cell cultures and in mice. J. Bacteriol. 92:862-868. 1966.-A comparison was made of the effects of ultraviolet (UV) irradiation or heating at 56 C on the interferon-stimulating capacity of Newcastle disease virus in primary chick embryo fibroblast (CE) cultures, in L-cell cultures, and in the intact mouse. The data obtained indicated the critical importance of the host cell system used for interferon production. Virus inactivated by UV irradiation, as well as infective virus, was an effective stimulus of interferon production in L cells and in mice, and this property persisted on continued irradiation. In contrast, in CE cell cultures, infective virus produced no interferon, whereas UV-irradiated virus produced maximal interferon titers when all infectivity was destroyed; continued irradiation resulted in a rapid loss of the interferon-stimulating capacity of the virus. Virus inactivated at 56 C did not produce interferon in CE or L-cell cultures. In the intact mouse, on the other hand, heat-inactivated virus was capable of stimulating the release of significant levels of circulating interferon.

Animals↗