Embryo Project Encyclopedia

During 1964, David Hubel and Torsten Wiesel studied the short and long term effects of depriving kittens of vision in one eye. In their experiments, Wiesel and Hubel used kittens as models for human children. Hubel and Wiesel researched whether the impairment of vision in one eye could be repaired or not and whether such impairments would impact vision later on in life. The researchers sewed one eye of a kitten shut for varying periods of time. They found that when vision impairments occurred to the kittens right after birth, their vision was significantly affected later on in life, as the cells that were responsible for processing visual information redistributed to favor the unimpaired eye. Hubel and Wiesel worked together for over twenty years and received the 1981 Nobel Prize for Physiology or Medicine for their research on the critical period for mammalian visual system development. Hubel and Wiesel’s experiments with kittens showed that there is a critical period during which the visual system develops in mammals, and it also showed that any impairment of that system during that time will affect the lifelong vision of a mammal.

In the 1950s and 1960s, Roger Sperry performed experiments on cats, monkeys, and humans to study functional differences between the two hemispheres of the brain in the United States. To do so he studied the corpus callosum, which is a large bundle of neurons that connects the two hemispheres of the brain. Sperry severed the corpus callosum in cats and monkeys to study the function of each side of the brain. He found that if hemispheres were not connected, they functioned independently of one another, which he called a split-brain. The split-brain enabled animals to memorize double the information. Later, Sperry tested the same idea in humans with their corpus callosum severed as treatment for epilepsy, a seizure disorder. He found that the hemispheres in human brains had different functions. The left hemisphere interpreted language but not the right. Sperry shared the Nobel Prize in Physiology or Medicine in 1981for his split-brain research.

David Hunter Hubel studied the development of the visual system and how the brain processes visual information in the US during the twentieth century. He performed multiple experiments with kittens in which he sewed kitten’s eyes shut for varying periods of time and monitored their vision after reopening them. Hubel, along with colleague Torsten Wiesel, received the 1981 Nobel Prize in Physiology or Medicine for that research. By using kittens as models for human children and sewn eyes as models for congenital vision disorders, Hubel’s research demonstrated how vision impairments can affect the development of the visual system in humans. Furthermore, Hubel’s research has informed surgeons about the importance of operating on infants with vision impairments during the first months of life to prevent deterioration of the visual cortex of the brain and permanent vision loss.

Nancy Goodman Brinker founded the largest breast cancer organization in the US, Susan G. Komen for the Cure, during the twentieth century. In 1982, Brinker created the organization, Susan G. Komen for the Cure, in memory of her sister, who had died of breast cancer two years earlier. During the early twentieth century, breast cancer was socially stigmatized, very few people discussed the disease, and there were limited treatment options available for those diagnosed with the disease. Breast cancer is one of the most prevalent forms of cancer and it affects almost 12 percent of women worldwide. In 1983, Brinker created the Susan G. Komen Race for Cure, a fundraising and awareness event for breast cancer. The organization provides funding for research, advocacy, and programs related to breast cancer. In the early 2000s, Brinker served as the US Ambassador to Hungary and, later, as the US Chief of Protocol. In 2009, US president Barack Obama awarded her the Presidential Medal of Freedom, the nation’s highest civilian honor. In 2017, Brinker serves as the Chair of Global Strategy at Susan G. Komen for the Cure and as the World Health Organization’s Goodwill Ambassador for Cancer Control. Brinker’s activism in the field of breast cancer raised awareness, public attention, funding, and support for women affected by breast cancer.

Mammography or mastography is an imaging technology used in the twentieth century for the detection of breast cancer and other breast abnormalities. Breast cancer is an abnormal growth in breast tissue that can spread to other parts of the body and cause death. Breast cancer affects about twelve percent of women worldwide. In the twenty-first century, mammography is one of the most accurate tools for screening and diagnosing breast cancer. A mammogram is the image created by sending low-level X-rays through breast tissue then filmed or a digital recorder captures the image, which a radiologist analyzes. A Senographe is the instrument used to create the mammogram to screen for breast cancer and other breast diseases. Mammography significantly decreased the number of deaths from breast cancer, but it can also give false positive results and cause physicians to over diagnose that may result in treatment for diseases women do not have.

In 1964, Jerome Horwitz synthesized the drug zidovudine, commonly abbreviated ZDV, otherwise known as azidothymidine, or AZT, at Wayne State University School of Medicine in Detroit, Michigan. Horwitz and his colleagues originally developed zidovudine to treat cancers caused by retroviruses. In 1983, Nobel Prize in Physiology or Medicine recipients Françoise Barré-Sinoussi and Luc Montagnier discovered a new retrovirus, the human immunodeficiency virus, or HIV, at the Pasteur Institute in Paris, France. HIV weakens the immune system and can be passed from a pregnant woman to her fetus in utero, or in the womb. In 1984, scientist Marty St. Clair and her team determined that zidovudine could help treat HIV. Zidovudine was the first medicine discovered to help treat HIV and prevent the transmission of HIV from affected pregnant women to fetuses in the womb by blocking the virus from passing through the placenta.

In 2010, Albert L. Hsu, Izebella Khchikyan, and Pamela Stratton published “Invasive and Non-invasive Methods for the Diagnosis of Endometriosis,” henceforth “Methods for the Diagnosis of Endometriosis,” in Clinical Obstetrics and Gynecology. In the article, the authors describe how specific types of endometriotic lesions appear in the body and evaluate five methods for diagnosing endometriosis. Endometriosis is the growth of endometrium, the tissue that normally lines the inside of the uterus, outside of the uterus. The authors state that although endometriosis impacts many women, the condition is difficult to identify. They identify laparoscopy, an invasive surgical procedure, as the most accurate diagnostic method. By analyzing the effectiveness of available diagnostic methods, the authors help physicians diagnose endometriosis and increase the quality of life for affected women.

Leuprolide acetate, or leuprorelin, is a manufactured drug that has been prescribed as a treatment for endometriosis, a medical condition in which body tissue that typically lines the uterus grows outside of the uterus, since 1989. Leuprorelin is a modified version of a gonadotropin-releasing hormone, a type of hormone that helps regulate the female menstrual cycle. The drug inhibits the production of estrogen, a female sex hormone that enables endometrial gland growth. After two weeks of injections, leuprorelin stops the production of estrogen, and without estrogen, endometrial glands become inactive. That decreases the growth of uterine tissue outside of the uterus, which helps decrease the pain associated with endometriosis. Although physicians commonly prescribe leuprorelin as of 2019, women with endometriosis have reported adverse side effects and health complications.

Menstrual tampons are feminine hygiene devices, usually made of absorbent cotton, that are temporarily inserted into the vagina for absorbing a woman’s blood during menstruation. In 1931, Earl Haas invented the menstrual tampon most commonly used in the twenty-first century. Later, Gertrude Tendrich produced the first commercial tampon brand, Tampax, using Haas’s patented design. Tendrich and Haas’s tampon was made of tightly compacted absorbent cotton, shaped like a bullet, and had a string attached at the base that allowed for easy removal from the woman’s body. Some tampons had a plastic or cardboard applicator, while other digital tampons could be inserted with a finger. The invention of the tampon expanded women’s options for efficient menstrual flow management solutions and allowed women to be more physically active while menstruating.

On 16 October 1916, Margaret Sanger opened one of the first birth control clinics in the United States in Brooklyn, New York, which some have called the Brownsville Clinic. Located at 46 Amboy Street, the clinic was a place where Sanger and her staff verbally communicated with women seeking information about birth control. During the early 1900s, both birth control and abortion were illegal in the US, and publication or circulation of information on both topics was deemed obscene and illegal by the federal Comstock Act. However, women still sought means to control unwanted pregnancies and visited the clinic to learn about birth control. The clinic was open for only ten days. It shut down after being found guilty of violation of the Comstock Act. The Brownsville Clinic represented a step toward the eventual founding of Planned Parenthood Federation of America, which Sanger led. Despite being short-lived, America’s first birth control clinic provided educational resources to women in New York and raised awareness of the birth control movement in the US through media exposure.