Canine Gastric Carcinomas: A Histopathological and Immunohistochemical Study and Similarities with the Human Counterpart.

Canine gastric carcinoma (CGC) affects both sexes in relatively equal proportions, with a mean age of nine years, and the highest frequency in Staffordshire bull terriers. The most common histological subtype in 149 CGC cases was the undifferentiated carcinoma. CGCs were associated with increased chronic inflammation parameters and a greater chronic inflammatory score when Helicobacter spp. were present. Understanding the molecular pathways of gastric carcinoma is challenging. All markers showed variable expression for each subtype. Expression of the cell cycle regulator 14-3-3σ was positive in undifferentiated, tubular and papillary carcinomas. This demonstrates that 14-3-3σ could serve as an immunohistochemical marker in routine diagnosis and that mucinous, papillary and signet-ring cell (SRC) carcinomas follow a 14-3-3σ independent pathway. p16, another cell cycle regulator, showed increased expression in mucinous and SRC carcinomas. Expression of the adhesion molecules E-cadherin and CD44 appear context-dependent, with switching within tumor emboli potentially playing an important role in tumor cell survival, during invasion and metastasis. Within neoplastic emboli, acinar structures lacked expression of all markers, suggesting an independent molecular pathway that requires further investigation. These findings demonstrate similarities and differences between dogs and humans, albeit further clinicopathological data and molecular analysis are required.

Effects of human subjects requirements on classroom research: multidisciplinary evidence.

PROFESSORS WHO INCLUDE THEIR STUDENTS as subjects in classroom-based research projects typically must submit to a review by their university's research ethics committee (REC) even in cases which present only minimal risks, and when the investigation is intended for evaluation of teaching approaches only, and not for publication. Results of a web-based survey with 378 respondents indicate that the perceived costs of the review process may outweigh the perceived benefits to subjects. A logistic regression analysis identifies the time it takes to complete the review application, the time it takes to receive a response, and the necessity of revising a project as significant factors in respondents viewing the REC process as a barrier to research. Instituting policies of expedited review for minimal-risk classroom research and exempting evaluations that are not to be published, both of which are permitted under the current regulations, would decrease burdens on both researchers and REC members, and foster improvement of teaching.