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Biomedical subjects

W A Gibson

Publications and source records attributed to W A Gibson.

At least 19 recordsLinked to original sources
PubMed1988

Reproductive toxicity studies of ademetionine.

S-Adenosyl-L-methionine sulphate-p-toluene sulphonate (ademetionine, SAMe), a donor of methyl groups, was examined for effects upon embryofoetal toxicity following both premating treatment and treatment during pregnancy and for peri- and post-natal toxicity in the rat at dosages of 0, 100, 200 and 400 mg/kg/d SAMe ion by subcutaneous or intravenous administration. Embryofoetal toxicity was also examined in the New Zealand White rabbit at dosages of 0, 10, 20 and 40 mg/kg/d SAMe by intravenous administration. Treatment was considered to be without adverse effect upon any of the reproductive parameters examined on either F0 or on the untreated F1 generations. There was no indication that treatment adversely affected the litter parameters including the incidences of malformations, anomalies and skeletal variants. Some slight changes in the activity of the F1 females derived from F0 animals given 400 mg/kg/d were considered to be of minimal importance. In contrast to the above, adverse effects upon the parents were noted at 400 mg/kg/d including local tissue reaction at the injection sites and retardation of body weight gain. In the intravenous studies some rigidity and dyspnoea were noted following administration. Following subcutaneous premating treatment there was also evidence of histopathological change to the kidney of the female rat. Increased water consumption was noted in this latter study and amongst females rearing offspring in the embryo foetal toxicity study in which the compound was administered intravenously. At the lower dosages administered to the rat some local tissue reaction was evident as was some retardation of body weight gain, minimal at the lowest intravenous dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Abnormalities, Drug-Induced↗
PubMed1987

Mesovarian leiomyomas in the rat.

Prolonged treatment with two chemically distinct beta-stimulants, Salbutamol and Terbutaline, resulted in mesovarian leiomyomas in Sprague-Dawley rats. Development of these tumors induced by Salbutamol was prevented by concurrent administration of the beta-blocker Propranolol. Mesovarian leiomyomas induced by Salbutomol did not show any regression or progression during a 44-week postdosing recovery period. This report also gives the first recorded incidence of spontaneous mesovarian leiomyomas in the rat.

Albuterol↗
PubMed1985

Human subjects in dental research: coping with the regulations. Council on Dental Research.

The rules and regulations pertaining to human subjects in research have evolved in response to ethical concerns for the protection of the rights and welfare of such subjects. However, investigators quite often are not well informed on what is required of them in the conduct of their clinical studies. Failure to be provided with sufficient information may be part of the problem, but the nature of such rules and regulations and their diversity and complexity certainly are sources of confusion. This article presents an overview of some of the major components and processes involved in the implementation of the federal regulations. It is hoped that this presentation will lead to a better understanding of the roles of the investigator, the institutional review boards, and the institutional and the federal agencies involved in the protection of human research subjects.

Consent Forms↗
PubMed1984

Chemopreventive effects of beta-carotene and 13-cis-retinoic acid on salivary gland tumors.

The chemopreventive effects of beta-carotene and 13-cis-retinoic acid (RA) on chemically induced salivary gland tumors were studied in rats. Young male Sprague-Dawley rats were injected in one of the submandibular salivary glands with 1 mg of dimethylbenzanthracene (DMBA) dissolved in olive oil. The contralateral gland was injected with the vehicle alone. Rats were divided into four groups and were fed ad libitum a semisynthetic diet supplemented with 0 or 100 mg beta-carotene/kg diet, or 20 or 100 mg RA/kg diet. Rats were killed at 22 weeks after the DMBA treatment, and tumors were examined histologically. Tumors were generally found to be squamous cell carcinomas or poorly differentiated neoplasms resembling squamous cell carcinomas. The tumor incidence was slightly lower in rats fed the diet supplemented with beta-carotene. RA had no appreciable effect on tumor incidence. A high activity of gamma-glutamyl transpeptidase was histochemically demonstrated in the tumors. There were some mortalities in the beta-carotene and RA supplemented groups, especially in the group fed high levels of RA. This mortality appeared to be related to vitamin K becoming somewhat limited.

9,10-Dimethyl-1,2-benzanthracene↗