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Amphioxus, and the Mosaic Theory of Development (1893), by Edmund Beecher Wilson

Edmund Beecher Wilson experimented with Amphioxus (Branchiostoma) embryos in 1892 to identify what caused their cells to differentiate into new types of cells during the process of development. Wilson shook apart the cells at early stages of embryonic development, and he observed the development of the isolated cells. He observed that in the normal development of Amphioxus, all three main types of symmetry, or cleavage patterns observed in embryos, could be found. Wilson proposed a hypothesis that reformed the Mosaic Theory associated with Wilhelm Roux in Germany.

Format: Articles

Subject: Experiments

The Inheritance of Acquired Characteristics (1924), by Paul Kammerer

The Inheritance of Acquired Characteristics is a book published in 1924, written by Paul Kammerer, who studied developmental biology in Vienna, Austria, in the early twentieth century. The Inheritance of Acquired Characteristics summarizes Kammerer's experiments, and explains their significance. In his book, Kammerer aims to explain how offspring inherit traits from their parents. Some scholars criticized Kammerer's reports and interpretations, arguing that they were inaccurate and misleading, while others supported Kammerer's work.

Format: Articles

Subject: Publications, Theories

Stem Cell Tourism

When James Thomson of the University of Wisconsin announced in 1998 that he had derived and cultured human embryonic stem cells(hESCs), Americans widely believed-and accepted-that stem cells would one day be the basis of a multitude of regenerative medical techniques. Researchers promised that they would soon be able to cure a variety of diseases and injuries such as cancer, diabetes, Parkinson's, spinal cord injuries, severe burns, and many others. But it wasn't until January 2009 that the Food and Drug Administration approved the first human clinical trials using hESCs.

Format: Articles

Subject: Theories, Ethics

Embryo Blotting Paper Models

Anatomical models have always been a mainstay of descriptive embryology. As the training of embryologists grew in the late 1800s, so too did the need for large-scale teaching models. Embryo wax models, such as those made by Adolf Ziegler and Gustav Born, were popular in the latter part of the nineteenth century and the early twentieth century as a way to visualize, in three dimensions, the fine detail of embryos without the aid of a microscope.

Format: Articles

Subject: Technologies

Francis Galton (1822-1911)

Sir Francis Galton was a British science writer and amateur researcher of the late nineteenth century. He contributed greatly to the fields of statistics, experimental psychology and biometry. In the history of biology, Galton is widely regarded as the originator of the early twentieth century eugenics movement. Galton published influential writings on nature versus nurture in human personality traits, developed a family study method to identify possible inherited traits, and devised laws of genetic inheritance prior to the rediscovery of Gregor Mendel's work.

Format: Articles

Subject: People, Reproduction

Charles Benedict Davenport (1866-1944)

Charles Benedict Davenport was an early twentieth-century experimental zoologist. Davenport founded both the Station for Experimental Evolution and the Eugenics Record Office at Cold Spring Harbor in New York. Though he was a talented statistician and skilled scientist, Davenport's scientific achievements are eclipsed by his lasting legacy as the scientific leader of the eugenics movement in the US.

Format: Articles

Subject: People, Reproduction

Adolf Ziegler

The scientific field of embryology experienced great growth in scope and direction in Germany from approximately 1850 to 1920. During this time, Adolf Ziegler and his son Friedrich crafted hundreds of wax embryo models, representing a shift in how embryos were viewed and used. Their final products, whether human or trout embryos, showcased the now lost collaboration between wax modeling artists and embryologists.

Format: Articles

Subject: People

Stazione Zoologica Anton Dohrn, Naples, Italy

The Stazione Zoologica Anton Dohrn (Anton Dohrn Zoological Station) is a public research institute focusing on biology and biodiversity. Hereafter called the Station, it was founded in Naples, Italy, in 1872 by Anton Dohrn. The type of research conducted at the Station has varied since it was created, though initial research focused on embryology. At the turn of the twentieth century, researchers at the Station established the sea urchin (Echinoidea) as a model organism for embryological research.

Format: Articles

Subject: Organizations, People, Places

Meiosis in Humans

Meiosis, the process by which sexually-reproducing organisms generate gametes (sex cells), is an essential precondition for the normal formation of the embryo. As sexually reproducing, diploid, multicellular eukaryotes, humans rely on meiosis to serve a number of important functions, including the promotion of genetic diversity and the creation of proper conditions for reproductive success.

Format: Articles

Subject: Processes, Reproduction

Richard Woltereck's Concept of Reaktionsnorm

Richard Woltereck first described the concept of Reaktionsnorm (norm of reaction) in his 1909 paper 'Weitere experimentelle Untersuchungen uber Art-veranderung, speziell uber das Wesen quantitativer Artunterschiede bei Daphniden' ('Further investigations of type variation, specifically concerning the nature of quantitative differences between varieties of Daphnia'). This concept refers to the ways in which the environment can alter the development of an organism, and its adult characteristics.

Format: Articles

Subject: Theories

Leo Loeb (1869-1959)

Leo Loeb developed an experimental approach to studying cancer and pioneered techniques for tissue culture and in vitro tissue transplantation which impacted early-to-mid twentieth century experimental embryology. Loeb received his medical degree from the University of Zurich in 1897. As part of his doctorate, he completed a thesis on the outcomes of tissue transplantation in guinea pigs. Loeb's thesis inspired a life-long interest in tissue transplantation.

Format: Articles

Subject: People

Hans Spemann (1869-1941)

Hans Spemann was an experimental embryologist best known for his transplantation studies and as the originator of the "organizer" concept. One of his earliest experiments involved constricting the blastomeres of a fertilized salamander egg with a noose of fine baby hair, resulting in a partially double embryo with two heads and one tail.

Format: Articles

Subject: People

Nicole Marthe Le Douarin (1930- )

Nicole Marthe Le Douarin was one of the first progressive female pioneers of developmental and embryological research. Some of her most notable and ground-breaking work involves grafting quail and chicken embryos together in order to study the developmental fate of each contributing embryo. Le Douarin was born in Brittany, France, on 20 August 1930. As an only child she was inspired by her mother, a school teacher at the time, to develop a passion for learning.

Format: Articles

Subject: People

George McDonald Church (1954- )

George McDonald Church studied DNA from living and from extinct species in the US during the twentieth and twenty-first centuries. Church helped to develop and refine techniques with which to describe the complete sequence of all the DNA nucleotides in an organism's genome, techniques such as multiplex sequencing, polony sequencing, and nanopore sequencing. Church also contributed to the Human Genome Project, and in 2005 he helped start a company, the Personal Genome Project. Church proposed to use DNA from extinct species to clone and breed new organisms from those species.

Format: Articles

Subject: People

Eugenical Sterilization in the United States (1922), by Harry H. Laughlin

Eugenical Sterilization in the United States is a 1922 book in which author Harry H. Laughlin argues for the necessity of compulsory sterilization in the United States based on the principles of eugenics. The eugenics movement of the early twentieth century in the US focused on altering the genetic makeup of the US population by regulating immigration and sterilization, and by discouraging interracial procreation, then called miscegenation.

Format: Articles

Subject: Outreach, Legal, Ethics, Publications

The Impact of the Safe Motherhood Initiative from 1987 to 2000

In 1987, the World Health Organization, or WHO, took action to improve the quality of maternal health around the world through the declaration of the Safe Motherhood Initiative, or the SMI, at an international conference concerning maternal mortality in Nairobi, Kenya. Initially, the SMI aimed to reduce the prevalence of maternal mortality around the world, as over 500,000 women died during pregnancy and childbirth annually at the time of its inception, while about 98 percent of those deaths occurred in low-income countries.

Format: Articles

Subject: Organizations, Reproduction

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

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

Leuprorelin as a Treatment for Endometriosis

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.

Format: Articles

Subject: Processes

Victor Jollos (1887-1941)

Victor Jollos studied fruit flies and
microorganisms in Europe and the US, and he introduced the concept of
Dauermodifikationen in the early 1900s. The concept of
Dauermodifikationen refers to environmentally-induced traits that are
heritable for only a limited number of generations. Some scientists
interpreted the results of Jollos's work on Paramecium and Drosophila as
evidence for cytoplasmic inheritance. Jollos was forced to emigrate from
Germany to the United States due to anti-semitic government policies in

Format: Articles

Subject: People

Neonatal Respiratory Distress Syndrome and Its Treatment with Artificial Surfactant

Neonatal respiratory distress syndrome, previously called hyaline membrane disease, is a respiratory disease affecting premature newborns. Neonatal respiratory distress syndrome involves shallow breathing, pauses between breaths that last a few seconds, or apnea, and a bluish tinge to the infant’s skin. The syndrome occurs when microscopic sacs called alveoli in infant lungs do not produce surfactant, a liquid that coats the inside of the lungs and helps them inflate during breathing.

Format: Articles

Subject: Disorders

The Ponseti Method to Treat Club Foot

Ignacio Vives Ponseti developed a noninvasive method for treating congenital club foot in the US during the late 1940s. Congenital club foot is a birth deformity in which one or both of an infant's feet are rotated inward beneath the ankle, making normal movement rigid and painful. Ponseti developed a treatment method, later called the Ponseti method, that consisted of a series of manipulations and castings of the club foot performed in the first few months of life.

Format: Articles

Subject: Technologies

Thomson, et al. v. Thompson, et al. (2001)

Thomson, et al. v. Thompson, et al. was a lawsuit filed in the United States District Court for the District of Columbia on 8 May 2001 as Civil Action Number 01-CV-0973. This lawsuit was filed in hopes of gaining injunctive relief against a moratorium on the federal funding of stem cell research. The plaintiffs in the case were seven prominent scientists who performed embryonic stem cell research and three patients: James Thomson, Roger Pedersen, John Gearhart, Douglas Melton, Dan Kaufman, Alan Trounson, Martin Pera, Christopher Reeve, James Cordy, and James Tyree.

Format: Articles

Subject: Legal

Andreas Vesalius (1514–1564)

Andreas Vesalius, also called Andries van Wesel, studied anatomy during the sixteenth century in Europe. Throughout his career, Vesalius thoroughly dissected numerous human cadavers, and took detailed notes and drawings of his research. Compiling his research, Vesalius published an anatomy work titled De humani corporis fabrica libri septem (On the fabric of the human body in seven books). The Fabrica included illustrations of dissected men, women, and uteruses with intact fetuses.

Format: Articles

Subject: People

The Dalkon Shield

The Dalkon Shield was an intrauterine contraceptive device (IUD) that women used in the early 1970s and 1980s. Produced by the A.H. Robins Company in the US, the Dalkon Shield was a contraceptive device placed directly into a woman’s uterus that was supposed to prevent the development of a fetus in the uterus. In the 1980s, researchers uncovered an array of severe birth defects and injuries caused by the Dalkon shield, including pelvic infection, infertility, and death of the user. Eventually the A.H.

Format: Articles

Subject: Technologies