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As a component of a recent academic review, the Department of Anatomy and Neurosciences faculty at the University of Texas Medical Branch in Galveston, Texas, developed a questionnaire designed to compare the curricula, direction, and challenges of their department with the approximately 140 anatomy departments in the U.S. and Canada. The response was overwhelming in that over 80% of the schools returned a completed questionnaire. One of the areas of interest revealed by this survey was a growing concern over significant changes in both medical school curricula and the future of anatomy departments. Most departments still used traditional lectures to present course material and the majority of the scheduled contact hours were in the dissection laboratory; however, other teaching formats, such as case studies and small group discussions, accounted for significantly more of the teaching effort. Nearly 20% of the schools were making major modifications in their teaching methods. The general trend was to include more integrated, problem-based learning and computer-assisted teaching while reducing overall content, didactic lectures, and rote memorization. The role and need for traditionally trained gross anatomists in medical education appeared to be diminishing as curricular reform moved toward more student-directed, facultyfacilitated programs. Concurrently, the recruitment and career development of gross anatomy faculty appeared to be influenced more by funding status than by academic training or teaching experience, as most departmental chairman were willing to hire non-anatomists and "train" them to assume an often reduced teaching load in gross anatomy courses. In addition, fewer graduate students were being trained in classical gross anatomy, a trend that better suited the emerging student-directed medical school curricula. The reduction in classically trained anatomists also appeared to reflect the widespread practice whereby anatomy faculty were rewarded far more for research than for teaching. Although the continued inclusion of gross anatomy in medical education appeared to be assured, its traditional mode of presentation and academic prominence will likely change by the turn of the century.Key words: academic review, curriculum, student-directed curricula o 1994 wiley-Liss, Inc. INTRODUCTIONGross anatomy has always held a central position in medical education. With the perceived need for educational reform that would provide more clinical exposure and promote more active learning experiences during the basic science years, the role of gross anatomy has become less clear. As a consequence of an academic review of the Anatomy and Neurosciences Department at the University of Texas Medical Branch in Galveston (UTMB), our faculty designed a comprehensive questionnaire which was distributed in 1991 to medical schools throughout the U.S. and Canada. The objectives of the questionnaire were to collect information on how gross anatomy in North America is currently taught; to learn in what ways, if any, anatomy dep...

The initial differentiation of endoderm at the time of onset of implantation, and the subsequent rapid differentiation of visceral and parietal endoderm were studied in the rat and mouse. Transmission electron microscopy illustrates the reorientation and loosening of embryonic cell mass cells during implantation, as well as cytological evidence that endoderm cells have differentiated. Using scanning electron microscopy, parietal endoderm consists of individual stellate cells with numerous peripheral branching filopodia. As these cells migrate abembryonically, the rest of the embryonic cell mass becomes recompacted. The visceral endoderm proliferates and forms a columnar epithelium which has the cytological characteristic of an absorptive epithelium and is able to ingest exogenous proteins. Thus, by 24 hours after implantation, the two endodermal derivatives have assumed widely diverse shapes and different types of associations and rates of replication, and are probably performing different functions.

Recent studies show that nonamidated gastrins (Gly-gastrin and progastrin) stimulate colonic proliferation. However, the role of nonamidated vs. amidated gastrins in colon carcinogenesis has not been defined. We measured intermediate markers of carcinogenesis in transgenic mice overexpressing either progastrin (hGAS) or amidated gastrin (INS-GAS) in response to azoxymethane (AOM). The hGAS mice showed significantly higher numbers of aberrant crypt foci (140-200% increase) compared with that in wild-type (WT) and INS-GAS mice (P < 0.05) after AOM treatment. The bromodeoxyuridine-labeling index of colonic crypts also was significantly elevated in hGAS mice vs. that in WT and INS-GAS mice. The results therefore provide evidence for a mitogenic and cocarcinogenic role of nonamidated gastrins (progastrin), which is apparently not shared by the amidated gastrins. Although nonamidated gastrins are now believed to mediate mitogenic effects via novel receptors, amidated gastrins mediate biological effects via different receptor subtypes, which may explain the difference in the cocarcinogenic potential of nonamidated vs. amidated gastrins. In conclusion, our results provide strong support for a cocarcinogenic role for nonamidated gastrins in colon carcinogenesis.

The peri-implantation period is a critical time during murine development. Although the importance of nitric oxide has been demonstrated during gestation, its role in implantation has not been fully defined. The aim of this study was to quantify (by Western blotting) two prominent nitric oxide synthase (NOS) isoforms, inducible (iNOS) and endothelial (eNOS) and localize all three forms [iNOS, eNOS, and neuronal (nNOS)] by immunohistochemistry in uterine tissue from days 4 through 8 of pregnancy. By day 6, iNOS values were significantly elevated in implantation sites compared with interimplantation regions and continued to rise through day 8. Analysis of eNOS was similar, but implantation site values peaked by days 6 and 7. Labelled iNOS cells were within the decidua, around myometrial vessels, and within the ectoplacental cone. At implantation, eNOS was conspicuous, displaying label adjacent to the embryo in vessels of the primary decidual zone. nNOS was localized mainly in the mesometrium and myometrium and did not appear to change throughout the peri-implantation period. The increased iNOS and eNOS values following implantation in the embryonic site may imply roles in tissue remodelling, immunosuppression and vasoregulation. Nitric oxide may play an important role in the mechanisms of implantation where these factors are keys to successful pregnancy.