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Bernadine Healy (1944–2011)

During the twentieth century in the United States, Bernadine Patricia Healy was a cardiologist who served as the first female director of the National Institutes of Health or NIH and the president of both the American Heart Association and the American Red Cross. Healy conducted research on the different manifestations of heart attacks in women compared to men. At the time, many physicians underdiagnosed and mistreated coronary heart disease in women. Healy's research illustrated how coronary heart disease affected women.

Format: Articles

Subject: People

Julia Barlow Platt (1857-1935)

Julia Barlow Platt studied neural crests in animal embryos and became involved in politics in the US during the nineteenth and twentieth centuries. She researched how body and head segments formed in chicks (Gallus gallus) and spiny dogfish (Squalus acanthias). Platt observed that in the mudpuppy (Necturus maculosus), the coordinated migration of neural crest cells in the embryo produced parts of the nervous system, bones, and connective tissues in the head.

Format: Articles

Subject: People

Robert Guthrie (1916–1995)

Robert Guthrie developed a method to test infants for phenylketonuria (PKU) in the United States during the twentieth century. PKU is an inherited condition that causes an amino acid called phenylalanine to build to toxic levels in the blood. Untreated, PKU causes mental disabilities. Before Guthrie’s test, physicians rarely tested infants for PKU and struggled to diagnosis it. Guthrie’s test enabled newborns to be quickly and cheaply screened at birth and then treated for PKU if necessary, preventing irreversible neurological damage.

Format: Articles

Subject: People

"Human Toxoplasmosis: Occurrence in Infants as an Encephalomyelitis Verification of Transmission to Animals" (1939), by Abner Wolf et al.

In a series of experiments during mid 1930s, a team of researchers in New York helped establish that bacteria of the species Toxoplasma gondii can infect humans, and in infants can cause toxoplasmosis, a disease that inflames brains, lungs, and hearts, and that can organisms that have it. The team included Abner Wolf, David Cowen, and Beryl Paige. They published the results of their experiment in Human Toxoplasmosis: Occurrence in Infants as an Encephalomyelitis Verification of Transmission to Animals.

Format: Articles

Subject: Experiments, Reproduction, Disorders

Noninvasive Fetal Aneuploidy Detection for Trisomy 21, 13, and 18

Noninvasive fetal aneuploidy detection technology allows for the detection of fetal genetic conditions, specifically having three chromosomes, a condition called aneuploidy, by analyzing a simple blood sample from the pregnant woman. Dennis Lo and Rossa Chiu researched methods of detection of aneuploidies in the early twenty-first century. Their research has been specifically applied to three trisomies, trisomy twenty-one known as Down syndrome, trisomy eighteen known as Edwards Syndrome, and trisomy thirteen known as Patau Syndrome.

Format: Articles

Subject: Technologies

Wilhelm His, Sr. (1831-1904)

Wilhelm His, Sr. was born on 9 July 1831 in Basel, Switzerland, to Katharina La Roche and Eduard His. He began his medical studies at Basel in 1849 and later transferred to the University of Bern during the winter semester of 1849-1850. A year later, His arrived at the University of Berlin, where he studied under Johannes Müller and Robert Remak. For his clinical training, His attended the University of Würzburg from 1852-1853.

Format: Articles

Subject: People

Wilhelm Roux (1850-1924)

Wilhelm Roux was a nineteenth-century experimental embryologist who was best known for pioneering Entwicklungsmechanik, or developmental mechanics. Roux was born in Jena, Germany, on 9 June 1850, the only son of Clotilde Baumbach and a university fencing master, F. A. Wilhelm Ludwig Roux. Roux described himself as an aloof child, but when he was fourteen he cultivated a passion for science that was encouraged by the director at Oberrealschule in Meiningen.

Format: Articles

Subject: People

Felix Anton Dohrn

Felix Anton Dohrn is best remembered as the founder of the Stazione Zoologica di Napoli, the world' s first permanent laboratory devoted to the study of marine organisms. Dohrn was born on 29 December 1840 in Stettin, Pomerania (now Poland), to a wealthy merchant family. Dohrn's paternal grandfather, Heinrich, trained as a surgeon and then established a sugar refinery, while Dohrn's father, Carl August Dohrn, who inherited the family business, became interested in natural history through Alexander von Humboldt, a family friend.

Format: Articles

Subject: People

Walter Jakob Gehring (1939-2014)

Walter Jakob Gehring discovered the homeobox, a DNA segment found in a specific cluster of genes that determine the body plan of animals, plants, and fungi. Gehring identified the homeobox in 1983, with the help of colleagues while isolating the Antennapedia (Antp) gene in fruit flies (Drosophila) at the University of Basel in Basel, Switzerland. Hox genes, a family of genes that have the homeobox, determine the head-to-tail (anterior-posterior) body axis of both vertebrates and invertebrates.

Format: Articles

Subject: People

Making Visible Embryos (2008- ), by Tatjana Buklijaz and Nick Hopwood

Making Visible Embryos is a 2008 online exhibition of embryos authored and designed by Tatjana Buklijaz and Nick Hopwood who work in the Department of History and Philosophy of Science at the University of Cambridge. Hopwood's research on the history of Ziegler wax models and the use of visual aids to promote the teaching and learning of science is well known.

Format: Articles

Subject: Organizations, Outreach

Digit Regeneration Is Regulated by Msx1 and BMP4 in Fetal Mice (2003), by Manjong Han et al.

In the early 2000s, Manjong Han, Xiaodang Yang, Jennifer Farrington, and Ken Muneoka investigated how genes and proteins in fetal mice (Mus musculus) influenced those fetal mice to regenerate severed toes at Tulane University in New Orleans, Louisiana. The group used hind limbs from mice to show how the gene Msx1 (Homeobox 7) functions in regenerating amputated digits.

Format: Articles

Subject: Experiments

Light Therapy for Neonatal Jaundice

Light therapy, also called phototherapy, exposes infants with jaundice, a yellowing of the skin and eyes, to artificial or natural light to break down the buildup of bilirubin pigment in the blood. Bilirubin is an orange to red pigment produced when red blood cells break down, which causes infants to turn into a yellowish color. Small amounts of bilirubin in the blood are normal, but when there is an accumulation of excess bilirubin pigment, the body deposits the excess bilirubin in the layer of fat beneath the skin.

Format: Articles

Subject: Technologies

Edward Drinker Cope's Law of Acceleration of Growth

The Law of Acceleration of Growth is a theory proposed by Edward Drinker Cope in the US during the nineteenth century. Cope developed it in an attempt to explain the evolution of genera by appealing to changes in the developmental timelines of organisms. Cope proposed this law as an additional theory to natural selection.

Format: Articles

Subject: Theories

Gordon Watkins Douglas (1921-2000)

Gordon Watkins Douglas researched cervical cancer, breach delivery, and treatment of high blood pressure during pregnancy in the US during the twentieth century. He worked primarily at Bellevue Hospital Center in New York, New York. While at Bellevue, he worked with William E. Studdiford to develop treatments for women who contracted infections as a result of illegal abortions performed throughout the US in unsterile environments.

Format: Articles

Subject: People

Ponseti's Treatment for Congenital Clubfoot (1963)

In 1963, Ignacio Ponseti and Eugene Smoley experimentally determined an effective and minimally invasive method of treating congenital clubfoot. Congenital clubfoot is a disorder in which a newborn’s foot is rigidly turned inwards and upwards. During the early 1960s, orthopedists often relied on invasive surgical procedures to treat clubfoot.

Format: Articles

Subject: Experiments

"Mitochondrial DNA and Human Evolution" (1987), by Rebecca Louise Cann, Mark Stoneking, and Allan Charles Wilson

In 1987 Rebecca Louise Cann, Mark Stoneking, and Allan Charles Wilson published Mitochondrial DNA and Human Evolution in the journal Nature. The authors compared mitochondrial DNA from different human populations worldwide, and from those comparisons they argued that all human populations had a common ancestor in Africa around 200,000 years ago. Mitochondria DNA (mtDNA) is a small circular genome found in the subcellular organelles, called mitochondria.

Format: Articles

Subject: Publications, Theories

Embryos in Wax (2002), by Nick Hopwood

Embryos in Wax: Models from the Ziegler Studio is a history of embryo wax modeling written by science historian Nick Hopwood. Published by the Whipple Museum of the History of Science University of Cambridge and the Institute of the History of Medicine University of Bern, 2002, the book, like the wax models, helps exemplify the visual and material culture of science.

Format: Articles

Subject: Publications

Gamete Intra-Fallopian Transfer (GIFT)

Various techniques constitute assisted reproduction, one of which is gamete intra-fallopian transfer (GIFT). The first example of GIFT involved primates during the 1970s; however, the technology was unsuccessful until 1984 when an effective GIFT method was invented by Ricardo Asch at the University of Texas Health Sciences Center and the procedure resulted in the first human pregnancy. The GIFT technique was created in hopes of generating an artificial insemination process that mimicked the physiological sequences of normal conception.

Format: Articles

Subject: Technologies, Reproduction

Hermaphrodites and the Medical Invention of Sex (1998), by Alice Domurat Dreger

Hermaphrodites and the Medical Invention of Sex, by historian of science Alice Domurat Dreger, was published in 1998 by Harvard University Press. In the book, Dreger describes how many doctors and scientists treated human hermaphrodites from the late nineteenth century to the early twentieth century. She states that during this time period, many physicians and scientists struggled to determine the nature sex, and to support a classification of sex as male or female, many physicians and scientists resorted to viewing a person's gonads for identification of his or her sex.

Format: Articles

Subject: Publications, Theories, Disorders

Endoderm

Endoderm is one of the germ layers-- aggregates of cells that organize early during embryonic life and from which all organs and tissues develop. All animals, with the exception of sponges, form either two or three germ layers through a process known as gastrulation. During gastrulation, a ball of cells transforms into a two-layered embryo made of an inner layer of endoderm and an outer layer of ectoderm. In more complex organisms, like vertebrates, these two primary germ layers interact to give rise to a third germ layer, called mesoderm.

Format: Articles

Subject: Processes

Germ Layers

A germ layer is a group of cells in an embryo that interact with each other as the embryo develops and contribute to the formation of all organs and tissues. All animals, except perhaps sponges, form two or three germ layers. The germ layers develop early in embryonic life, through the process of gastrulation. During gastrulation, a hollow cluster of cells called a blastula reorganizes into two primary germ layers: an inner layer, called endoderm, and an outer layer, called ectoderm.

Format: Articles

Subject: Theories, Processes

"Viable Offspring Derived from Fetal and Adult Mammalian Cells" (1997), by Ian Wilmut et al.

In the 1990s, Ian Wilmut, Jim McWhir, and Keith Campbell performed experiments while working at the Roslin Institute in Roslin, Scotland. Wilmut, McWhir, and Campbell collaborated with Angelica Schnieke and Alex J. Kind at PPL Therapeutics in Roslin, a company researching cloning and genetic manipulation for livestock. Their experiments resulted in several sheep being born in July 1996, one of which was a sheep named Dolly born 5 July 1996.

Format: Articles

Subject: Experiments

Mesoderm

Mesoderm is one of the three germ layers, groups of cells that interact early during the embryonic life of animals and from which organs and tissues form. As organs form, a process called organogenesis, mesoderm interacts with endoderm and ectoderm to give rise to the digestive tract, the heart and skeletal muscles, red blood cells, and the tubules of the kidneys, as well as a type of connective tissue called mesenchyme. All animals that have only one plane of symmetry through the body, called bilateral symmetry, form three germ layers.

Format: Articles

Subject: Processes

"The Developmental Capacity of Nuclei Taken from Intestinal Epithelium Cells of Feeding Tadpoles" (1962), by John B. Gurdon

In 1962 researcher John Bertrand Gurdon at the University of Oxford in Oxford, England, conducted a series of experiments on the developmental capacity of nuclei taken from intestinal epithelium cells of feeding tadpoles. In the experiments, Gurdon conducted nuclear transplantation, or cloning, of differentiated cells, or cells that have already specialized to become one cell type or another, in tadpoles. Gurdon's experiment showed that differentiated adult cells could be induced to an undifferentiated state, where they could once again become multiple cell types.

Format: Articles

Subject: Experiments