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Displaying 251 - 275 of 966 items.

Exchange Transfusion for Jaundiced Newborns in the United States

Exchange transfusion is the replacement of blood from newborn infants with elevated bilirubin level in their blood stream with donor blood containing normal bilirubin levels. Newborn infants that experience jaundice, the yellowing of the skin and eyes, have a buildup of bilirubin, a chemical that occurs during red blood cell breakdown, or hemolysis. Exchange transfusion is a therapy developed throughout the 1940s by Louis Diamond and a group of surgeons at the Children’s Medical Center in Boston, Massachusetts.

Format: Articles

Subject: Technologies

Elinor Catherine Hamlin (1924- )

Elinor Catherine Hamlin founded and helped fund centers in Ethiopia to treat women affected by fistulas from obstetric complications. Obstetric fistulas develop in women who experience prolonged labor, as the pressure placed on the pelvis by the fetus during labor causes a hole, or fistula, to form between the vagina and the bladder (vesicovaginal fistula) or between the vagina and the rectum (rectovaginal fistula). Both of those conditions result in urinary or fecal incontinence, which often impacts womenÍs social status within their communities.

Format: Articles

Subject: People, Reproduction

Hamlin Fistula Ethiopia (1974- )

Hamlin Fistula Ethiopia is a nonprofit organization that began in 1974 as a joint endeavor by Reginald and Catherine Hamlin and the Addis Ababa Fistula Hospital in Addis Ababa, Ethiopia. Hamlin Fistula Ethiopia promotes reproductive health in Ethiopia by raising awareness and implementing treatment and preventive services for women affected by obstetric fistulas. It also aims to restore the lives of women afflicted with obstetric fistulas in Ethiopia and eventually to eradicate the condition.

Format: Articles

Subject: Organizations, Reproduction, Outreach

"Gene Regulation for Higher Cells: A Theory" (1969), by Roy J. Britten and Eric H. Davidson

In 1969, Roy J. Britten and Eric H. Davidson published Gene Regulation for Higher Cells: A Theory, in Science. A Theory proposes a minimal model of gene regulation, in which various types of genes interact to control the differentiation of cells through differential gene expression. Britten worked at the Carnegie Institute of Washington in Washington, D.C., while Davidson worked at the California Institute of Technology in Pasadena, California. Their paper was an early theoretical and mechanistic description of gene regulation in higher organisms.

Format: Articles

Subject: Publications

David Starr Jordan (1851-1931)

David Starr Jordan studied fish and promoted eugenics in the US during the late nineteenth and early twentieth centuries. In his work, he embraced Charles Darwin s theory of evolution and described the importance of embryology in tracing phylogenic relationships. In 1891, he became the president of Stanford University in Stanford, California. Jordan condemned war and promoted conservationist causes for the California wilderness, and he advocated for the eugenic sterilization of thousands of Americans.

Format: Articles

Subject: People, Reproduction

"Conservatism in Obstetrics" (1916), by Edwin B. Cragin

In 1916 Edwin B. Cragin in the United States published Conservatism in Obstetrics in which he discussed medical practices and techniques to preserve the vitality of pregnant women and their fetuses. Cragin argued that women who give birth via cesarean section, the surgical act of making an incision through both the abdomen and uterus to remove the fetus from a pregnant woman's womb, must rely on that method for future births. That claim was later coined the Dictum of Cragin.

Format: Articles

Subject: Publications

Edmund Beecher Wilson (1856-1939)

Edmund Beecher Wilson contributed to cell biology, the study of cells, in the US during the end of the nineteenth and the beginning of the twentieth centuries. His three editions of The Cell in Development and Inheritance (or Heredity) in 1896, 1900, and 1925 introduced generations of students to cell biology. In The Cell, Wilson described the evidence and theories of his time about cells and identified topics for future study. He helped show how each part of the cell works during cell division and in every step of early development of an organism.

Format: Articles

Subject: People

Gustav Jacob Born (1851-1900)

Gustav Jacob Born was an experimental embryologist whose original work with amphibians served as the platform for his wax-plate method of embryo modeling, heteroblastic (different tissues) and xenoplastic (similar species) transplantation methods, environmental influences on sex ratio studies, and proposed function of the corpus luteum. He was born 22 April 1851 in Kempen, Prussia, but his family moved to the larger city of Görlitz within a year after Born's birth. His father was Marcus Born, a physician and public health officer who practiced in the town of Görlitz.

Format: Articles

Subject: People

Alan Mathison Turing (1912-1954)

Alan Mathison Turing was a British mathematician and computer scientist who lived in the early twentieth century. Among important contributions in the field of mathematics, computer science, and philosophy, he developed a mathematical model of morphogenesis. This model describing biological growth became fundamental for research on the process of embryo development.

Format: Articles

Subject: People

General Embryological Information Service, published annually by the Hubrecht Laboratory, 1949-1981

The General Embryological Information Service (GEIS) was an annual report published by the Hubrecht Laboratory in Utrecht, The Netherlands from 1949 to 1981 that disseminated contemporary research information to developmental biologists. The purpose of the annual report was to catalog the names, addresses, and associated research of every developmental biologist in the world. Pieter Nieuwkoop edited each issue from 1949 until 1964, when Job Faber began assisting Nieuwkoop. Bert Z. Salome joined the editing team in 1968 before Nieuwkoop ceased editing duties in 1971.

Format: Articles

Subject: Organizations

Beatrice Mintz (1921- )

Beatrice Mintz is a brilliant researcher who has developed techniques essential for many aspects of research on mouse development. She produced the first successful mouse chimeras and meticulously characterized their traits. She has worked with various cancers and produced viable mice from the cells of a teratoma. Mintz participated in the development of transgenic mice by the incorporation of foreign DNA into a mouse genome.

Format: Articles

Subject: People

Ian Donald (1910–1987)

Ian Donald was an obstetrician who developed the technology and therapy of ultrasound diagnostics during the twentieth century in Europe. Ultrasound is a medical diagnostic technique that uses sound waves to produce images of the inside of the body. During the early 1900s, physicians had no way to see inside a woman’s uterus during pregnancy. Donald developed the first method of scanning human internal anatomy in real time, which enabled doctors to diagnose potentially fatal tumors and cysts.

Format: Articles

Subject: People

Boris Ephrussi (1901-1979)

Boris Ephrussi studied fruit flies, yeast, and mouse genetics and development while working in France and the US during the twentieth century. In yeast, Ephrussi studied how mutations in the cytoplasm persisted across generations. In mice he studied the genetics of hybrids and the development of cancer. Working with George Wells Beadle on the causes of different eye colors in fruit flies, Ephrussi's research helped establish the one-gene-one-enzyme hypothesis. Ephrussi helped create new embryological techniques and contributed the theories of genetics and development.

Format: Articles

Subject: People

Edward B. Lewis (1918-2004)

Edward B. Lewis studied embryonic development in Drosophila, including the discovery of the cis-trans test for recessive genes, and the identification of the bithorax complex and its role in development in Drosophila. He shared the 1995 Nobel Prize in Physiology or Medicine with Christiane Nüsslein-Volhard and Eric F. Wieschaus for work on genetic control of early embryonic development.

Format: Articles

Subject: People

Sex-determining Region Y in Mammals

The Sex-determining Region Y (Sry in mammals but SRY in humans) is a gene found on Y chromosomes that leads to the development of male phenotypes, such as testes. The Sry gene, located on the short branch of the Y chromosome, initiates male embryonic development in the XY sex determination system. The Sry gene follows the central dogma of molecular biology; the DNA encoding the gene is transcribed into messenger RNA, which then produces a single Sry protein.

Format: Articles

Subject: Processes

The Y-Chromosome in Animals

The Y-chromosome is one of a pair of chromosomes that determine the genetic sex of individuals in mammals, some insects, and some plants. In the nineteenth and twentieth centuries, the development of new microscopic and molecular techniques, including DNA sequencing, enabled scientists to confirm the hypothesis that chromosomes determine the sex of developing organisms. In an adult organism, the genes on the Y-chromosome help produce the male gamete, the sperm cell. Beginning in the 1980s, many studies of human populations used the Y-chromosome gene sequences to trace paternal lineages.

Format: Articles

Subject: Reproduction, Theories

Barbara McClintock's Transposon Experiments in Maize (1931–1951)

Barbara McClintock conducted experiments on corn (Zea mays) in the United States in the mid-twentieth century to study the structure and function of the chromosomes in the cells. McClintock researched how genes combined in corn and proposed mechanisms for how those interactions are regulated. McClintock received the Nobel Prize in Physiology or Medicine in 1983, the first woman to win the prize without sharing it. McClintock won the award for her introduction of the concept of transposons, also called jumping genes.

Format: Articles

Subject: Experiments

Essay: Homology

Homology is a central concept of comparative and evolutionary biology, referring to the presence of the same bodily parts (e.g., morphological structures) in different species. The existence of homologies is explained by common ancestry, and according to modern definitions of homology, two structures in different species are homologous if they are derived from the same structure in the common ancestor.

Format: Essays and Theses

Subject: Processes

In re Agent Orange Product Liability Litigation (1979-1984)

In the legal case In re Agent Orange Product Liability Litigation of the early 1980s, US military veterans of the Vietnam War sued the US chemical companies that had produced the herbicide Agent Orange, and those companies settled with US veterans out of court. Agent Orange contains dioxin, a chemical later shown to disrupt the hormone system of the body and to cause cancer. As veterans returned to the US from Vietnam, scientists further confirmed that exposure to Agent Orange caused a variety of cancers in veterans and developmental problems in the veterans' children.

Format: Articles

Subject: Legal, Ethics

"Cellular death in morphogenesis of the avian wing" (1962), by John W. Saunders Jr., et al.

In the early 1960s, John W. Saunders Jr., Mary T. Gasseling, and Lilyan C. Saunders in the US investigated how cells die in the developing limbs of chick embryos. They studied when and where in developing limbs many cells die, and they studied the functions of cell death in wing development. At a time when only a few developmental biologists studied cell death, or apoptosis, Saunders and his colleagues showed that researchers could use embryological experiments to uncover the causal mechanisms of apotosis.

Format: Articles

Subject: Experiments

Stanley Alan Plotkin (1932– )

Stanley Alan Plotkin developed vaccines in the United States during the mid to late twentieth century. Plotkin began his research career at the Wistar Institute in Philadelphia, Pennsylvania, where he studied the rubella virus. In pregnant women, the rubella virus caused congenital rubella syndrome in the fetus, which led to various malformations and birth defects. Using WI-38 cells, a line of cells that originated from tissues of aborted fetuses, Plotkin successfully created RA27/3, a weakened strain of the rubella virus, which he then used to develop a rubella vaccine.

Format: Articles

Subject: People

Eugen Steinach (1861–1944)

Eugen Steinach researched sex hormones and their effects on mammals in the late nineteenth and early twentieth centuries in Europe. He experimented on rats by removing their testicles and implanting them elsewhere in their bodies, and he found that the testes interstitial cells produce male sex hormones. He developed the Steinach Rejuvenation Procedure, which he claimed could rejuvenate men by increasing their production of sex hormones. Steinach’s work on female sex hormones and on ovarian extracts led to the development of the first standardized injectable estrogen.

Format: Articles

Subject: People

Robert William Briggs (1911-1983)

Robert William Briggs was a prolific developmental biologist. However, he is most identified with the first successful cloning of a frog by nuclear transplantation. His later studies focused on the problem of how genes influence development.

Format: Articles

Subject: People

Impact of Air Pollution on Reproductive Health” (1999), by Radim Srám

In 1999, researcher Radim Srám, sometimes spelled Radim Šrám, published his article “Impact of Air Pollution on Reproductive Health” in the journal Environmental Health Perspectives. In the article, Srám analyzes the effects of exposure to air pollution, which can include harmful chemicals, on fetal growth and development. Srám discusses how industrialized countries such as the US and China have led to an increase in the global amount of respirable air pollutants.

Format: Articles

Subject: Publications

Ernst Haeckel's Biogenetic Law (1866)

The biogenetic law is a theory of development and evolution proposed by Ernst Haeckel in Germany in the 1860s. It is one of several recapitulation theories, which posit that the stages of development for an animal embryo are the same as other animals' adult stages or forms. Commonly stated as ontogeny recapitulates phylogeny, the biogenetic law theorizes that the stages an animal embryo undergoes during development are a chronological replay of that species' past evolutionary forms.

Format: Articles

Subject: Theories