The purpose of this study was to determine whether estrogens exerted a direct inhibitory effect on progesterone synthesis in isolated human luteal cells in vitro. It was found that hCG stimulated progesterone synthesis by luteal cells, obtained from corpora lutea of the menstrual cycle, whereas cells isolated from corpora lutea of pregnancy were unresponsive to exogenous hCG. Estradiol markedly inhibited (P less than 0.001) this hCG effect in luteal cells of the menstrual cycle, and this inhibition was dose dependent. Estradiol did not block the stimulation of cAMP accumulated by hCG in the luteal cells of the cycle but did inhibit the stimulatory effect of dibutyryl cAMP on progesterone synthesis. These data suggest that estrogens may directly cause functional luteolysis in the human and that its site of action may be after the accumulation of cAMP.

Underrepresented-minority (URM) students at the University of South Florida College of Medicine increased from 4.9% to 10.5% of the total student body from 1991 to 1997. During that period it became clear that some majority and minority students had serious academic difficulties with the first-year curriculum and that a higher proportion of the minority matriculants had difficulties. In response, the college in 1997 created the Summer Pre-matriculation Program to reduce the number of first-year students who had academic difficulty. In the summer before they matriculate in the college, the students complete a six-week program of lectures, small-group discussions, compute-aided instruction, and laboratory instruction in biochemistry, human embryology, and gross anatomy. URM students, non-science majors, and students who have been away from the academic environment (e.g., pursuing medicine as a second career) are given priority for the 20 positions available each year. At the end of the first cohort's first medical school year, the academic performances of program participants and other students were compared, and it was clear that the program participants had performed as well as or slightly better than their counterparts in gross anatomy, biochemistry, and human embryology. Further, the program participants performed at or above the class average in medical school courses for which they had not had targeted instruction during the program. The College of Medicine is committed to diversifying its student body and realizes that diverse students bring varying levels of academic preparation as well as diversity in cultural and academic backgrounds. Concerted efforts such as the pre-matriculation program may be required to normalize the "playing field" at the very outset of medical school and to ensure that every matriculant has an equal opportunity to succeed.

The mechanism of skeletal muscle hypoxia has a profound effect on its subsequent transcriptional response. We identified several potential candidates as markers of skeletal muscle ischaemic damage.

No abstract