内分泌信号传导3.pdf

Environmental Signaling (ES-101) Case 3: DES--endocrine disruption begins Session Objectives Students will be able to: Describe changes in the thinking of scientists about trans-placental disease Define iatrogenic Describe ways in which pharmaceuticals might have unintended consequences In this session students will consider a story, based on historical facts, about DES. Read this passage out loud, or ask for a volunteer to do so. It was the early 1970’s, so the doctors in the elevator wore polyester shirts with long lapels and fat ties. The three men stood in the back of the elevator, discussing their related cases as they descended to the first floor. In the last month their well-renowned clinic associated with one of New England’s most prestigious hospitals had seen 8 young women (all under the age of 26) with a virulent cancer--clear-celled carcinoma of the uterus. This form of cancer was normally very rare, and previously seen only in women well past menopause. Standing in front of them, and closer to the elevator door was a nurse, partly included in their conversation, who worked with them in the clinic, and whose daughter was one of the patients they were discussing. All eight women had gone through surgery which removed their uterus, vagina, ovaries, and pelvic region lymph glands, and the doctors held that their cancer prognosis was good. However, this treatment obviously drastically changed the women’s reproductive future, and posed further health consequences--some of them had not even completed puberty. They were searching for a factor that linked all the women together, and might explain how they ended up with this disease. This cluster of cases remained enigmatic; so far their commonalities were completely banal, and shared with millions of other women. As the elevator stopped, the bell dinged, and the doors opened to the lobby. Instead of stepping out, the nurse turned to the doctors behind her and said “I