The reincarnation of a biomedical researcher: from bench science to medical education.

After 33 years as a biomedical research scientist, I embarked on a new career in medical education. The transformation was awkward, difficult and exciting. Although I had assumed that previous experience in research and scholarship would stand me in good stead, such was hardly the case. I had to learn to navigate a strange new literature, replete with terms that I did not understand, and to deal with concepts that challenged my physico-chemical mindset. As I learned, I found myself discovering a field rich in essential questions, controversial hypotheses, and important potential applications. With my newly acquired knowledge and skills, I began to reflect on my own educational endeavors. I identified a number of outstanding issues and I designed studies to address them. What made these investigations particularly significant for me was their applicability. Although medical education is an exciting and meaningful career path, because of its low profile in most medical schools, few faculty are aware of the academic opportunities that it affords.

In utero exposure to tributyltin chloride differentially alters male and female fetal gonad morphology and gene expression profiles in the Sprague-Dawley rat.

Tributyltin (TBT) is an environmental contaminant commonly used in anti-fouling agents for boats, as well as a by-product from several industrial processes. It has been shown to accumulate in organisms living in areas with heavy maritime traffic thereby entering the food chain. Here, we determined the consequences of in utero exposure to TBT on the developing fetal gonads in the Sprague-Dawley rat. Timed pregnant rats were gavaged either with vehicle or TBT (0.25, 2.5, 10 or 20 mg/kg) from days 0 to 19 or 8 to 19 of gestation. On gestational day 20, dams were sacrificed; fetal testes and ovaries were processed for light (LM) or electron microscopic (EM) evaluation and RNA was prepared for gene expression profiling. At the highest doses of TBT the number of Sertoli cells and gonocytes was reduced, there were large intracellular spaces between Sertoli cells and gonocytes and there was an increased abundance of lipid droplets in the Sertoli cells; EM studies revealed abnormally dilated endoplasmic reticulum in Sertoli cells and gonocytes. In the intertubular region between adjacent interstitial cells, immunostaining for the gap junctional protein connexin 43 was strong in controls, whereas it was reduced or completely absent in treated rats. In the ovaries, TBT (20 mg/kg, days 0-19; 10 mg/kg, days 8-19) reduced the number of germ cells by 44% and 46%, respectively. On examining gene expression profiles in the testis, 40 genes out of 1176 tested were upregulated more than two-fold over control. While no genes were upregulated in the TBT exposed fetal ovary, eight genes were downregulated. In conclusion, in utero exposure to TBT resulted in gender-specific alterations in gonadal development and gene expression profiles suggesting that there may be different adaptive changes to toxicity in developing male and female rats.

The value of a philosophical perspective in teaching the basic medical sciences.

A major challenge for medical education is the cultivation of practitioners capable of embracing both the physico-chemical and transcendent dimensions of human life. A widely accepted approach to this dilemma has been the introduction of the humanities, and more specifically philosophy, into the medical curriculum. The integration of philosophical thinking into the educational process is, however, hampered by its apparent incompatibility with the scientific/reductionist mindset preeminent in modern medicine. A method of presenting relevant philosophic themes within the context of the basic medical sciences is proposed. It involves the identification and development of philosophic content inherent within the scientific subjects that we teach.