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C S Streett

Publications and source records attributed to C S Streett.

10 recordsLinked to original sources
PubMed1988

Morphologic stomach findings in rats and mice treated with the H2 receptor antagonists, ICI 125,211 and ICI 162,846.

The gross and histopathologic findings seen in the stomachs of rats and mice treated with 2 different H2 receptor antagonists are presented. Studies with the first drug, ICI 125,211, elicited dysplasia/carcinoma lesions in 17 of 828 treated rats with 12 of the 17 lesions occurring in the pyloric region of the stomach. No tumors occurred in mice on study for 18 months. Studies conducted with another drug candidate, ICI 162,846, produced neuroendocrine carcinomas in the stomach of rats and mice. Twenty-five rats out of 312 treated male and female rats had neuroendocrine carcinomas in the gastric fundus with a higher tumor incidence in females. In a 24-month mouse study with ICI 162,846, 45 of 300 treated mice developed neuroendocrine carcinomas in the gastric fundus with a higher incidence in males.

Animals↗
PubMed1986

A wound healing study of chlorhexidine digluconate in guinea pigs.

Formulations with and without chlorhexidine digluconate, a broad-spectrum antimicrobial, were tested for their effects on the healing of incisions and abrasions surgically induced in male guinea pigs. Formulations containing chlorhexidine were a skin cleanser formulation (4% w/v), a tinted tincture (0.5% w/v), and both 0.5 and 4% w/v aqueous solutions. Control materials were saline, and both the skin cleanser and the tincture formulations without chlorhexidine. Presurgical preparation was limited to closely clipping the hair and wiping each wound area with saline to remove loose hair, dander, and dirt. Each incision and abrasion was irrigated with its assigned material at surgery and daily thereafter until necropsy. Guinea pigs were killed on Days 3, 6, 9, 14, and 21, and wound sites were removed and fixed for histologic evaluation of healing. Daily progress of the wound healing appeared comparable for all treatment groups and there was no gross evidence of treatment effects at necropsy. For the animals with incisions, there were no remarkable histological differences among the treatment groups at Day 3. At Days 6 and 9, the two formulations containing 4% chlorhexidine produced a slight delay in healing when compared with the other treatment groups. These differences decreased with time, and by Day 21, there were no remarkable histological differences among animals of the various treatment groups. For the animals with abrasions, all treatment groups with and without chlorhexidine had slightly delayed healing compared to the saline control animals on Day 3 and 6.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Pathologic findings in the stomachs of rats treated with the H2-receptor antagonist tiotidine.

The gross and histopathologic findings seen in the stomach of rats treated with an H2-antagonist, tiotidine, will be presented. The data presented is from two studies, a six month oral (gavage) and dietary study in male rats, and a 12 month oral chronic toxicity study combined with a 24 month oncogenicity feeding study in rats. Significant findings in the stomach included fundic glandular dilatation, parietal cell atrophy, metaplastic fundic cells, fundic nuclear clusters, and dysplasia/carcinoma lesions. The chronology of the borderline type dysplasia/carcinoma lesions starting from the very early to the more advanced infiltrating carcinomas will be shown. A total of 17 rats with lesions of the dysplasia/carcinoma complex out of 828 treated rats from the two studies were present. No similar type lesions were seen in any of the 432 control rats examined. The importance of the diagnostic methods used in the examination of the stomach is stressed.

Animals↗
PubMedDate not supplied

Peer review in toxicologic pathology.

Peer review of histopathology findings in safety assessment studies involving rodents and other animals is a relatively recent procedure in toxicologic pathology. It serves to ensure the integrity of the pathology evaluation in safety studies, encourages consistency of diagnostic criteria and use of common terminology, and provides a method of continuing education for participants. The use of a standardized system of pathology nomenclature and diagnostic criteria, such as the Society of Toxicologic Pathologist's Guides for Toxicologic Pathology, is of great value in the procedure. Pathology reviews may involve government-sponsored bioassay programs, in-house industrial corporations, or individual peer reviews suggested or required by government regulatory agencies. Pathology Working Groups can be an integral part of the review process. The extent of the peer review is primarily dependent on the study results; however, other variables such as confidence of the data, study size and duration, complexity, and purpose are also important considerations. Essential components of any peer review, however, include selection of tissues/lesions for review, by a reviewing pathologist, discrepancy resolution, data modification, and documentation of all aspects of the review process. Specific procedures for pathology peer review are discussed. Disagreements among pathologists discovered in peer reviews can be resolved by several methods and examples will be presented. The entire pathology peer review process should be a learning experience for all involved and can help ensure the integrity of animal toxicology studies used for important regulatory decisions involving the use of chemicals in our society.

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