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The Role of the Notch signaling pathway in Somitogenesis

Among other functions, the Notch signaling pathway contributes to the development of somites in animals. It involves a cell signaling mechanism with a wide range of functions, including cellular differentiation, and the formation of the embryonic structures (embryogenesis). All multicellular animals use Notch signaling, which is involved in the development, maintenance, and regeneration of a range of tissues. The Notch signaling pathways spans two cells, and consists of receptor proteins, which cross one cell's membrane and interacts with proteins on adjacent cells, called ligands.

Format: Articles

Subject: Theories, Processes

Francis Sellers Collins (1950- )

Francis Sellers Collins helped lead the International Human Genome Sequencing Consortium, which helped describe the DNA sequence of the human genome by 2001, and he helped develop technologies used in molecular genetics while working in the US in the twentieth and twenty-first centuries. He directed the US National Center for Human Genome Research (NCHGR), which became the National Human Genome Research Institute (NHGRI), of the US National Institutes of Health (NIH), located in Bethesda, Maryland, from 1993 to 2008.

Format: Articles

Subject: People

Hedgehog Signaling Pathway

The hedgehog signaling pathway is a mechanism that directs the development of embryonic cells in animals, from invertebrates to vertebrates. The hedgehog signaling pathway is a system of genes and gene products, mostly proteins, that convert one kind of signal into another, called transduction. In 1980, Christiane Nusslein-Volhard and Eric F. Wieschaus, at the European Molecular Biology Laboratory in Heidelberg, Germany, identified several fruit fly (Drosophila melanogaster) genes.

Format: Articles

Subject: Processes

Ethics of Fetal Surgery

Surgeons sometimes operate on the developing fetuses in utero of pregnant women as a medical intervention to treat a number of congential abnormalities, operations that have ethical aspects. A. William Liley performed the first successful fetal surgery, a blood transfusion, in New Zealand in 1963 to counteract the effects of hemolytic anemia, or Rh disease.

Format: Articles

Subject: Ethics

United States v. Milan Vuitch (1971)

In the 1971 court case United States v. Milan Vuitch, hereafter US v. Vuitch, the US Supreme Court ruled that a Washington, DC law was constitutional by overturning a 1969 district court decision. Beginning in the early twentieth century, Washington, DC, prohibited abortions except for abortions performed to preserve the life or health of the pregnant woman. In 1969, Milan Vuitch, a physician in Washington, DC, was convicted of criminal abortion for providing an abortion when the woman’s life was not endangered.

Format: Articles

Subject: Legal

Medical Vibrators for Treatment of Female Hysteria

During the late 1800s through the early 1900s, physicians administered pelvic massages involving clitoral stimulation by early electronic vibrators as treatments for what was called female hysteria. Until the early 1900s, physicians used female hysteria as a diagnosis for women who reported a wide range of complaints and symptoms unexplainable by any other diagnosis at the time. According to historian Rachel Maines, physicians provided pelvic massages for thousands of years to female patients without it being considered erotic or sexually stimulating.

Format: Articles

Subject: Reproduction, Technologies, Ethics

Minnie Joycelyn Elders (1933–)

Minnie Joycelyn Elders, known as Joycelyn Elders, is a pediatrician and professor at the University of Arkansas for Medical Sciences in Little Rock, Arkansas. In 1953, Elders began to work with the US Army, where she trained as a physical therapist, being the only African American woman in her training class. Elders eventually became a medical doctor in 1956, specializing in pediatric endocrinology. In 1993, then US President Bill Clinton appointed Elders as the Surgeon General for the United States Public Health Service Commissioned Corps, which she served as until 1994.

Format: Articles

Subject: People

Mitochondria

All cells that have a nucleus, including plant, animal, fungal cells, and most single-celled protists, also have mitochondria. Mitochondria are particles called organelles found outside the nucleus in a cell's cytoplasm. The main function of mitochondria is to supply energy to the cell, and therefore to the organism. The theory for how mitochondria evolved, proposed by Lynn Margulis in the twentieth century, is that they were once free-living organisms.

Format: Articles

Subject: Organisms, Theories

Daubert v. Merrell Dow Pharmaceuticals, Inc. (1993)

In its 1993 decision Daubert v. Merrell Dow Pharmaceuticals, Inc., the US Supreme Court established the Daubert Standard for evaluating the admissibility of scientific knowledge as evidence in US federal courts. When it began in trial court, the case addressed whether or not Bendectin, an anti-nausea medication taken during pregnancy, caused birth defects. However, after the trial court dismissed the case for lack of admissible evidence, Daubert v. Merrell Dow Pharmaceuticals, Inc.

Format: Articles

Subject: Legal

Whole Woman's Health v. Hellerstedt (2016)

In the 2016 case Whole Woman's Health v. Hellerstedt, the US Supreme Court ruled unconstitutional the Texas requirements that abortion providers have admitting privileges at local hospitals and that abortion facilities meet ambulatory surgical center standards. Whole Woman’s Health represented abortion care providers in Texas and brought the case against the commissioner for the Texas Department of State Health Services, John Hellerstedt.

Format: Articles

Subject: Legal, Reproduction

Cocaine as a Teratogen

Cocaine use by pregnant women has a variety of effects on the embryo and fetus, ranging from various gastro-intestinal and cardiac defects to tissue death from insufficient blood supply. Thus, cocaine has been termed a teratogen, or an agent that causes defects in fetuses during prenatal development. Cocaine is one of the most commonly used drugs in the US and it has a history of both medical and illegal recreational use. It is a drug capable of a wide array of effects on physical and mental health.

Format: Articles

Subject: Reproduction, Disorders

Thomas Henry Huxley (1825-1895)

In nineteenth century Great Britain, Thomas Henry Huxley proposed connections between the development of organisms and their evolutionary histories, critiqued previously held concepts of homology, and promoted Charles Darwin's theory of evolution. Many called him Darwin's Bulldog. Huxley helped professionalize and redefine British science. He wrote about philosophy, religion, and social issues, and researched and theorized in many biological fields.

Format: Articles

Subject: People

The Development of Silicone Breast Implants for Use in Breast Augmentation Surgeries in the United States

In the 1960s, two plastic surgeons from the United States, Thomas Dillon Cronin and Frank Judson Gerow, collaborated with the Dow Corning Corporation, which specialized in silicone products, to create the first silicone breast implant. Surgeons used the implant, named the Cronin-Gerow implant, to improve the look of a woman’s breasts, by correcting for asymmetry, augmenting the size, or creating a more uplifted profile.

Format: Articles

Subject: Technologies, Processes

Ina May Gaskin (1940– )

Ina May Gaskin is a certified professional midwife, or CPM, in the US during the late twentieth and early twenty-first centuries. She worked at the Farm Midwifery Center in Summertown, Tennessee, a center well known for its low rates of intervention, which contributed to low rates of maternal and fetal mortality. One technique Gaskin used when assisting women with delivery helped resolve a complication called shoulder dystocia, which is when a part of the infant’s body is delivered, but the rest of the body is stuck in the birth canal.

Format: Articles

Subject: People

Zidovudine or Azidothymidine (AZT)

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.

Format: Articles

Subject: Processes

HeLa Cell Line

The HeLa cell line was the first immortal human cell line that George Otto Gey, Margaret Gey, and Mary Kucibek first isolated from Henrietta Lacks and developed at The Johns Hopkins Hospital in Baltimore, Maryland, in 1951. An immortal human cell line is a cluster of cells that continuously multiply on their own outside of the human from which they originated. Scientists use immortal human cell lines in their research to investigate how cells function in humans.

Format: Articles

Subject: Technologies, Experiments, People, Ethics