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Isotretinoin (Accutane) as a Teratogen

Isotretinoin is a molecule and a byproduct (metabolite) of vitamin A, and in greater than normal amounts in pregnant women, it can cause fetal abnormalities including cleft lips, ear and eye defects, and mental retardation. Isotretinoin is commonly called by its trade name Accutane, and it's a chemical compound derived from vitamin A, or retinoic acid. Doctors prescribe isotretinoin to treat severe acne. For pregnant women, too much vitamin A or isotretinoin can also cause greater than normal rates of stillbirths and fetal disintegrations after the ninth week of gestation.

Format: Articles

Subject: Reproduction, Disorders

The Role of the Notch Signaling Pathway in Myogenesis

Among other functions, the Notch signaling pathway forestalls the process of myogenesis in animals. The Notch signaling pathway is a pathway in animals by which two adjacent cells within an organism use a protein named Notch to mechanically interact with each other. Myogenesis is the formation of muscle that occurs throughout an animal's development, from embryo to the end of life. The cellular precursors of skeletal muscle originate in somites that form along the dorsal side of the organism.

Format: Articles

Subject: Theories, Processes

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

The e-Mouse Atlas Project (1992- )

The Edinburgh Mouse Atlas, also called the e-Mouse Atlas Project (EMAP), is an online resource comprised of the e-Mouse Atlas (EMA), a detailed digital model of mouse development, and the e-Mouse Atlas of Gene Expression (EMAGE), a database that identifies sites of gene expression in mouse embryos. Duncan Davidson and Richard Baldock founded the project in 1992, and the Medical Research Council (MRC) in Edinburgh, United Kingdom, funds the project.

Format: Articles

Subject: Technologies

Theophilus Shickel Painter (1889-1969)

Theophilus Shickel Painter studied the structure and
function of chromosomes in the US during in the early to mid-twentieth century. Painter worked at
the University of Texas at Austin in Austin, Texas. In the 1920s
and 1930s, Painter studied the chromosomes of the salivary gland
giant chromosomes of the fruit fly (Drosophila
melanogaster), with Hermann J. Muller. Muller and Painter
studied the ability of X-rays to cause changes in the chromosomes
of fruit flies. Painter also studied chromosomes in mammals.

Format: Articles

Subject: People

Hormone Releasing Intrauterine Devices

Hormone releasing intrauterine devices or hormonal IUDs are contraceptive devices placed in a woman’s uterus to prevent pregnancy by continuously releasing a low dose of certain hormones. Jouri Valter Tapani Luukkainen, a medical researcher at the University of Helsinki, introduced the first hormonal IUD in 1976. Luukkainen’s IUD was a plastic device shaped like a capital T.

Format: Articles

Subject: Technologies

Ericsson Method of Sperm Separation

In 1973, Ronald Ericsson developed the Ericsson method, which is a technique used to separate human male sperm cells by their genetic material. Ericsson, a physician and reproduction researcher, developed the method while conducting research on sperm isolation in Berlin, Germany, in the early 1970s. He found that the sperm cells that carry male-producing Y chromosomes move through liquid faster than the cells that carry female-producing X chromosomes.

Format: Articles

Subject: Technologies

“Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid” (1953), by James Watson and Francis Crick

In April 1953, James Watson and Francis Crick published “Molecular Structure of Nucleic Acids: A Structure of Deoxyribose Nucleic Acid” or “A Structure for Deoxyribose Nucleic Acid,” in the journal Nature. In the article, Watson and Crick propose a novel structure for deoxyribonucleic acid or DNA. In 1944, Oswald T. Avery and his group at Rockefeller University in New York City, New York published experimental evidence that DNA contained genes, the biological factors called genes that dictate how organisms grow and develop.

Format: Articles

Subject: Publications

Ian Hector Frazer (1953– )

Ian Hector Frazer studied the human immune system and vaccines in Brisbane, Australia, and helped invent and patent the scientific process and technology behind what later became the human papillomavirus, or HPV, vaccinations. According to the Centers for Disease Control and Prevention of the US, or CDC, HPV is the most common sexually transmitted infection, and can lead to genital warts, as well as cervical, head, mouth, and neck cancers.

Format: Articles

Subject: People

HIP Randomized Breast Cancer Screening Trial (1963–1982)

From 1963 to 1982, researchers in New York City, New York, carried out a randomized trial of mammography screening. Mammography is the use of X-ray technology to find breast cancer at early stages. The private insurance company Health Insurance Plan of Greater New York, or HIP, collaborated with researchers Sam Shapiro, Philip Strax, and Louis Venet on the trial. The researchers’ goal was to determine whether mammography screening reduced breast cancer mortality in women. The study included sixty thousand women aged forty to sixty-four.

Format: Articles

Subject: Experiments

Amanda Sims Memorial Fund (1930–1935)

In 1930, physician Joseph Colt Bloodgood founded the Amanda Sims Memorial Fund, or the ASMF, a United States cancer awareness organization that focused on spreading information about ways to detect and prevent cervical cancer in women, in Baltimore, Maryland. In partnership with nurse Florence Serpell Deakins Becker, Bloodgood promoted awareness of the early symptoms of cervical cancer among women and advocated for regular pelvic exams. The ASMF partnered with numerous women’s organizations throughout the United States, providing educational information to women of varying backgrounds.

Format: Articles

Subject: Organizations

“Effects of Maternal Age, Parity, and Smoking on the Risk of Stillbirth” (1994), by Elizabeth Raymond, Sven Cnattingius, and John Kiely

In April 1994, Elizabeth Raymond, Sven Cnattingius, and John Kiely published “Effects of Maternal Age, Parity, and Smoking on the Risk of Stillbirth” in the British Journal of Obstetrics and Gynecology, now known as BJOG: An International Journal of Obstetrics and Gynecology. The article examines how advanced maternal age, defined as delivery at thirty-five years old or older, cigarette smoking, and nulliparity, or the state of never having given birth, can negatively impact pregnancy.

Format: Articles

Subject: Reproduction, Publications

Emil Kraepelin (1856–1926)

Emil Kraepelin was a physician who studied people with mental illness in the late nineteenth and early twentieth centuries in modern-day Germany. Kraepelin's examination and description of the symptoms and outcomes of mental illness formed the basis for his classification of psychiatric disorders into two main groups, dementia praecox, now called schizophrenia, and manic-depressive psychosis, now called bipolar disorder. He was one of the first physicians to suggest that those researching mental illness should gain scientific knowledge only through close observation and description.

Format: Articles

Subject: People, Disorders

“A Two-Factor Hypothesis of Freezing Injury: Evidence from Chinese Hamster Tissue-Culture Cells” (1972), by Peter Mazur, Stanley Leibo, and Ernest Chu

In 1972, Peter Mazur, Stanley Leibo, and Ernest Chu published, “A Two-Factor Hypothesis of Freezing Injury: Evidence from Chinese Hamster Tissue-culture Cells,” hereafter, “A Two-Factor Hypothesis of Freezing Injury,” in the journal, Experimental Cell Research. In the article, the authors uncover that exposure to high salt concentrations and the formation of ice crystals within cells are two factors that can harm cells during cryopreservation. Cryopreservation is the freezing of cells to preserve them for storage, study, or later use.

Format: Articles

Subject: Publications, Theories

Somatic Cell Nuclear Transfer in Mammals (1938-2013)

In the second half of the
twentieth century, scientists learned how to clone organisms in some
species of mammals. Scientists have applied somatic cell nuclear transfer to clone human and
mammalian embryos as a means to produce stem cells for laboratory
and medical use. Somatic cell nuclear transfer (SCNT) is a technology applied in cloning, stem cell
research and regenerative medicine. Somatic cells are cells that
have gone through the differentiation process and are not germ
cells. Somatic cells donate their nuclei, which scientists

Format: Articles

Subject: Theories, Technologies, Processes

No-scalpel Vasectomy

No-scalpel vasectomy, or NSV or keyhole vasectomy, is a surgical method of sterilization that involves puncturing the skin of the scrotum to access the vas deferens, a tube that carries spermatozoa, or sperm, from the testes to the penis. The surgeon performing the procedure blocks the flow of sperm through the vas deferens, sterilizing the patient. NSV is a less invasive procedure, as it does not use a scalpel to make a deep cut on sensitive scrotal tissue.

Format: Articles

Subject: Technologies, People, Organizations, Places, Reproduction

Women’s Right to Know Act (2019) by Americans United for Life

In 2019, Americans United for Life, hereafter AUL, published a model legislation, called the Women’s Right to Know Act, in their annual publication Defending Life. The goal of the model legislation, which AUL annually updates, is to help state governments enact enhanced informed consent laws for abortion. The Women’s Right to Know Act requires physicians to provide specific information to women before they may consent to having an abortion.

Format: Articles

Subject: Legal, Publications, Reproduction

Stanley Alan Plotkin's Development of a Rubella Vaccine (1969)

In the US during the late 1960s, Stanley Alan Plotkin, John D. Farquhar, Michael Katz, and Fritz Buser isolated a strain of the infectious disease rubella and developed a rubella vaccine with a weakened, or attenuated, version of the virus strain. Rubella, also called German measles, is a highly contagious disease caused by the rubella virus that generally causes mild rashes and fever. However, in pregnant women, rubella infections can lead to developmental defects in their fetuses.

Format: Articles

Subject: Experiments

Karl Oskar Illmensee (1939–)

Karl Oskar Illmensee studied the cloning and reproduction of fruit flies, mice, and humans in the US and Europe during the twentieth and twenty-first centuries. Illmensee used nuclear transfer techniques (cloning) to create early mouse embryos from adult mouse cells, a technique biologists used in later decades to help explain how embryonic cells function during development. In the early 1980s, Illmensee faced accusations of fraud when others were unable to replicate the results of his experiments with cloned mouse embryos.

Format: Articles

Subject: People, People

Agent Orange as a Cause of Spina Bifida

Spina bifida is a birth defect that affects the spines of developing fetuses and infants, and research in the 20th century indicated that chemicals in the herbicide Agent Orange likely lead to the birth defect. People with spina bifida can have nerve damage, paralysis, and mental disabilities. During the Vietnam War in the 1960s, the US military employed Agent Orange and other herbicides to destroy enemy crops and forest cover until 1970.

Format: Articles

Subject: Disorders

Infant Mortality: Results of a Field Study in Johnstown, PA., Based on Births in One Calendar Year (1915), by Emma Duke

The book Infant Mortality: Results of a Field Study in Johnstown, PA., Based on Births in One Calendar Year (1915), written by Emma Duke, detailed one of the first infant mortality field studies conducted by the US Children's Bureau. In the study, Duke and her colleagues collected information about over one thousand infants in the city of Johnstown, Pennsylvania. They used that information, along with interviews conducted with the families of the infants, to identify factors that affected infant mortality rates in the community.

Format: Articles

Subject: Experiments, Publications

Ernest John Christopher Polge (1926-2006)

Twentieth-century researcher Ernest John Christopher Polge studied the reproductive processes of livestock and determined a method to successfully freeze, thaw, and utilize viable sperm cells to produce offspring in animals. In 1949, Polge identified glycerol as a cryoprotectant, or a medium that enables cells to freeze without damaging their cellular components or functions. Several years later, Polge used glycerol in a freezing process called vitrification, which enabled him to freeze poultry sperm, thaw that sperm, and use it to fertilize vertebrate embryos.

Format: Articles

Subject: People

In the Womb (2005), by Toby Mcdonald and National Geographic Channel

Written, produced, and directed by Toby Mcdonald, the 2005 National Geographic Channel film In the Womb uses the most recent technology to provide an intricate glimpse into the prenatal world. The technologies used, which include advanced photography, computer graphics, and 4-D ultrasound imaging, help to realistically illustrate the process of development and to answer questions about the rarely seen development of a human being.

Format: Articles

Subject: Outreach, 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