The program for professional values and ethics in medical education.

BACKGROUND: Medical educators are very interested in the teaching and evaluation of professional attitudes and behaviors among medical students, residents, and faculty. At Tulane University School of Medicine, we created the Program for Professional Values and Ethics in Medical Education (PPVEME) to return the focus of our curriculum to the physician-patient-community relationship and to the nurturing of professionalism. DESCRIPTION: PPVEME brings together students, residents, and faculty into learning teams that create longitudinal curricula about five themes: integrity, communication, teamwork, leadership, and service. The emphasis is on learner-driven self- and group-reflection about shared experiences, thus modeling essential professional attributes. EVALUATION: The program is evaluated using surveys, student and faculty focus groups, and portfolios developed by student volunteers on each team. The first program event, a retreat for entering medical students, was highly successful. CONCLUSIONS: PPVEME is an attempt to construct a medical school learning environment around professionalism. Evaluation over time will tell how successfully that has been accomplished.

Selective up-regulation of human alveolar macrophage collagenase production by lipopolysaccharide and comparison to collagenase production by fibroblasts.

Collagenase catalyzes the initial and rate-limiting step in interstitial collagen degradation. Human alveolar macrophages produce both a fibroblast-like procollagenase and tissue inhibitor of metalloproteinases (TIMP). To define the potential of macrophages to express collagenase and TIMP, we have studied the effects of certain cell culture variables and LPS on in vitro production of these proteins. Our data indicate: 1) human macrophages cultured in a 1/1 (v/v) mixture of HAM F-12:DME produce two- to three-fold greater quantities of procollagenase (but not TIMP) as compared to HAM F-12, DME, or alpha-MEM alone; 2) maximal collagenase expression requires the further addition of LPS, whereas TIMP production is optimized by 5% fetal bovine serum alone; 3) the up-regulation of macrophage procollagenase by LPS represents a highly selective biologic response when compared to changes induced in other secreted and intracellular proteins; 4) measurements of steady state procollagenase mRNA by Northern blot analysis suggest that the LPS effect is mediated at a pre-translational level; and finally 5) on a per cell basis, human alveolar macrophages cultured under optional conditions secrete approximately 20% of the collagenase and approximately 10% of the TIMP elaborated by stimulated human fibroblasts. We conclude that procollagenase and TIMP secretion by human alveolar macrophages in vitro is strikingly responsive to variations in cell culture conditions and that an especially noteworthy selective upregulation of procollagenase secretion by LPS is probably modulated by a transcriptional mechanism. The macrophage synthetic potential for procollagenase suggests a potentially important role for these cells in directly mediating collagen turnover.

Monocyte procollagenase and tissue inhibitor of metalloproteinases. Identification, characterization, and regulation of secretion.

Alveolar macrophages have been shown to secrete a procollagenase and the tissue inhibitor of metalloproteinases (TIMP), which are similar or identical to the corresponding proteins of human skin fibroblasts. Little is known, however, about the collagenolytic activity of normal human monocytes. We have applied immunologic, biochemical, and molecular biologic tools to examine the collagenolytic profile of freshly isolated peripheral blood monocytes. Our studies indicate that: 1) monocytes are capable of producing both procollagenase and TIMP that are identical to the corresponding products of skin fibroblasts, alveolar macrophages, and U-937 cells; 2) unstimulated monocytes in vitro secrete high levels of TIMP, but little or no procollagenase; 3) an as yet unidentified component(s) of serum are required for in vitro production of TIMP (but not procollagenase) by monocytes; 4) even when stimulated, monocytes secrete much smaller quantities of procollagenase in comparison with macrophages; and 5) regulation of the secretion of procollagenase and TIMP by monocytes exhibits a high degree of individual variability, but is nevertheless subject to clearly different control mechanisms than our previous findings would indicate for alveolar macrophages. Monocytes thus express a macrophage-like, rather than a neutrophil-like, profile of proteins capable of mediating collagen turnover, the regulation of which is distinct from that of more differentiated alveolar macrophages. Further study of monocyte and macrophage collagenolytic activities may provide insights into both the cell biology of mononuclear phagocyte maturation and the mechanisms by which such cells mediate the turnover of interstitial collagens.