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Etienne Geoffroy Saint-Hilaire (1772-1844)

Etienne Geoffroy Saint-Hilaire, commonly known as Geoffroy, studied animals, their anatomy and their embryos, and teratogens at the National Museum of Natural History in Paris, France in the eighteenth and nineteenth centuries. Geoffroy also helped develop several specialized fields in the life sciences, including experimental embryology. In his efforts to experimentally demonstrate the theory of recapitulation, Geoffroy developed techniques to intervene in the growth of embryos to see whether they would develop into different kinds of organisms.

Format: Articles

Subject: People

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

Early Infantile Autism and the Refrigerator Mother Theory (1943-1970)

In 1943, child psychiatrist Leo Kanner in the US gave the first account of Early Infantile Autism that encouraged psychiatrists to investigate what they called emotionally cold mothers, or refrigerator mothers. In 1949, Kanner published Problems of Nosology and Psychodynamics of Early Infantile Autism. In that article, Kanner described autistic children as reared in emotional refrigerators. US child psychiatrists claimed that some psychological or behavioral conditions might have origins in emotional or mental stress, meaning that they might be psychogenic.

Format: Articles

Subject: Disorders, Theories

American Eugenics Society (1926-1972)

The American Eugenics Society (AES) was established in the US by
Madison Grant, Harry H. Laughlin, Henry Crampton, Irving Fisher, and
Henry F. Osborn in 1926 to promote eugenics education programs for
the US public. The AES described eugenics as the study of improving
the genetic composition of humans through controlled reproduction of
different races and classes of people. The AES aided smaller eugenic
efforts such as the Galton Society in New York, New York, and the

Format: Articles

Subject: Organizations

Roy John Britten (1919-2012)

Roy John Britten studied DNA sequences in the US in the second
half of the twentieth century, and he helped discover repetitive
elements in DNA sequences. Additionally, Britten helped propose
models and concepts of gene regulatory networks. Britten studied the
organization of repetitive elements and, analyzing data from the
Human Genome Project, he found that the repetitive elements in DNA
segments do not code for proteins, enzymes, or cellular parts.
Britten hypothesized that repetitive elements helped cause cells to

Format: Articles

Subject: People

Experimental Studies on Germinal Localization (1904), by Edmund B. Wilson

At the turn of the twentieth century, Edmund B. Wilson
performed experiments to show where germinal
matter was located in molluscs. At Columbia University in New York City,
New York, Wilson studied what causes cells to differentiate during
development. In 1904 he conducted his experiments on molluscs, and he modified the
theory about the location of germinal matter in the succeeding years. Wilson and others modified the
theory of germinal localization to accommodate results that showed

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

“A Proposed Structure for the Nucleic Acids” (1953) by Linus Pauling and Robert Brainard Corey

In February 1953, Linus Pauling and Robert Brainard Corey, two scientists working at the California Institute of Technology in Pasadena, California, proposed a structure for deoxyribonucleic acid, or DNA, in their article “A Proposed Structure for the Nucleic Acids,” henceforth “Nucleic Acids.” In the article, Pauling and Corey suggest a model for nucleic acids, including DNA, that consisted of three nucleic acid strands wound together in a triple helix.

Format: Articles

Subject: Publications

Hox Genes and the Evolution of Vertebrate Axial Morphology Experiment (1995)

In 1995, researchers Ann Burke, Craig Nelson, Bruce Morgan, and Cliff Tabin in the US studied the genes that regulate the construction of vertebra in developing chick and mouse embryos, they showed similar patterns of gene regulation across both species, and they concluded that those patterns were inherited from an ancestor common to all vertebrate animals. The group analyzed the head-to-tail (anterior-posterior) axial development of vertebrates, as the anterior-posterior axis showed variation between species over the course of evolutionary time.

Format: Articles

Subject: Experiments

"The Limited In Vitro Lifetime of Human Diploid Cell Strains" (1964), by Leonard Hayflick

Leonard Hayflick in the US during the early 1960s showed that normal populations of embryonic cells divide a finite number of times. He published his results as 'The Limited In Vitro Lifetime of Human Diploid Cell Strains' in 1964. Hayflick performed the experiment with WI-38 fetal lung cells, named after the Wistar Institute, in Philadelphia, Pennsylvania, where Hayflick worked. Frank MacFarlane Burnet, later called the limit in capacity for cellular division the Hayflick Limit in 1974.

Format: Articles

Subject: Experiments

Agent Orange Birth Defects

Sprayed extensively by the US military in Vietnam, Agent Orange contained a dioxin contaminant later found to be toxic to humans. Despite reports by Vietnamese citizens and Vietnam War veterans of increased rates of stillbirths and birth defects in their children, studies in the 1980s showed conflicting evidence for an association between the two. In 1996, the US National Academy of Sciences reported that there was evidence that suggested dioxin and Agent Orange exposure caused spina bifida, a birth defect in which the spinal cord develops improperly.

Format: Articles

Subject: Disorders

Sheldon Clark Reed (1910-2003)

Sheldon Clark Reed helped establish the profession of genetic counseling in the US during the twentieth century. In 1947 Reed coined the term genetic counseling to describe the interaction of a doctor explaining to a patient the likelihood of passing a certain trait to their offspring. With physicians being able to test for genetic abnormalities like cystic fibrosis, Reed helped trained individuals give patients the tools to make informed decisions. In 1955 Reed published the book Counseling in Medical Genetics.

Format: Articles

Subject: People

Conrad Hal Waddington (1905-1975)

Conrad Hal Waddington was an embryologist and theoretical biologist. His early experimental work investigated aspects of embryonic induction and the properties of the organizer first identified by Hans Spemann and Hilde Mangold, while his later studies focused on genetic assimilation. Waddington is probably best known for developing the concept of the epigenetic landscape, and he also held significant interest in many different areas ranging from the visual arts and poetry to philosophy.

Format: Articles

Subject: People

The Formation of Reticular Theory

In the nineteenth century, reticular theory aimed to describe the properties of neurons, the specialized cells which make up the nervous system, but was later disconfirmed by evidence. Reticular theory stated that the nervous system was composed of a continuous network of specialized cells without gaps (synapses), and was first proposed by researcher Joseph von Gerlach in Germany in 1871.

Format: Articles

Subject: Theories

"Control of Corneal Differentiation by Extracellular Materials" (1974), by Stephen Meier and Elizabeth D. Hay

In 1974, Elizabeth Dexter Hay and Stephen Meier in the US conducted an experiment that demonstrated that the extracellular matrix, the mesh-like network of proteins and carbohydrates found outside of cells in the body, interacted with cells and affected their behaviors. In the experiment, Hay and Meier removed the outermost layer of cells that line the front of the eye, called corneal epithelium, from developing chick embryos.

Format: Articles

Subject: Experiments

Treatment of Anemia during Pregnancy (1931), by Lucy Wills

In 1931, physician Lucy Wills conducted a study of nutritional deficiencies that caused anemia in pregnant women in Bombay, India, later renamed Mumbai. Anemia is a lack of healthy red blood cells in the blood. Wills published the results of her study in the medical article 'Treatment of ‘Pernicious Anaemia of Pregnancy' and 'Tropical Anaemia'' in the British Medical Journal in 1931. Wills's research contributed to knowledge of anemia and the possible causes associated with the disease, such as the symptoms of fatigue and irritability.

Format: Articles

Subject: Experiments

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

Umbilical Cord Blood Stem Cells (UCBSC)

Umbilical cord blood (UCB) stem cells are hematopoietic stem cells (HSC) that are recovered from the blood of the umbilical cord and placenta after birth. Umbilical cord blood is rich in cells that express the CD34 molecule, a surface protein that identifies cells as stem cells. Prior to the discovery of UCB stem cells, it was standard procedure to discard the umbilical cord and placenta; now much effort is devoted to raising public awareness and to encouraging people to store or donate cord blood.

Format: Articles

Subject: Processes, Reproduction

In Vitro Fertilization

In vitro fertilization (IVF) is an assisted reproductive technology (ART) initially introduced by Patrick Steptoe and Robert Edwards in the 1970s to treat female infertility caused by damaged or blocked fallopian tubes. This major breakthrough in embryo research has provided large numbers of women the possibility of becoming pregnant, and subsequent advances have dramatically increased their chances. IVF is a laboratory procedure in which sperm and egg are fertilized outside the body; the term "in vitro" is Latin for "in glass."

Format: Articles

Subject: Technologies, Reproduction

Lap-Chee Tsui (1950-)

Lap-Chee Tsui is a geneticist who discovered the cystic fibrosis (CF) gene, and his research team sequenced human chromosome 7. As the location of the cystic fibrosis gene is now known, it is possible for doctors and specialists to identify in human fetuses the mutation that causes the fatal disease. Tsui's research also outlined the mechanisms for the development of cystic fibrosis, which were previously unknown.

Format: Articles

Subject: People, Reproduction

Davis v. Davis [Brief] (1992)

This case was the first of its kind to address questions of personhood in the context of in vitro fertilization of a human embryo. It laid a foundation for future cases to work from: specifically, this case established the importance of prior written agreements for disposition of frozen embryos. This was also the first court decision to borrow the word "pre-embryo" from bioethics to describe the in vitro embryo. This terminology has been copied by many states.

Format: Articles

Subject: Legal, Reproduction

Congenital Vertebral Defects

The spinal column is the central structure in the vertebrate body from which stability, movement, and posture all derive. The vertebrae of the spine are organized into four regions (listed in order from cranial to caudal): cervical, thoracic, lumbar, and pelvic. These regions are classified by their differences in curvature. The human spine usually consists of thirty-three vertebrae, seven of which are cervical (C1-C7), twelve are thoracic (T1-T12), five are lumbar (L1-L5), and nine are pelvic (five fused as the sacrum and four fused as the coccyx).

Format: Articles

Subject: Disorders, Reproduction

Robert Alan Good (1922-2003)

Robert Alan Good was an American physician and scientific researcher who explored the cellular mechanisms of immunity. His research and discoveries earned him the label of "father of modern immunology." Though his work in immunology is considered his greatest scientific achievement, Good is also well known for his work with tissue engineering. From his research on immunology, Good was able to perform the first successful allogeneic (donor and recipient are unrelated) bone marrow transplant.

Format: Articles

Subject: People

Charles Bonnet (1720-1793)

Charles Bonnet was a naturalist and philosopher in the mid eighteenth century. His most important contribution to embryology was the discovery of parthenogenesis in aphids, proving that asexual reproduction of offspring was possible. In his later life, he was an outspoken defender of the theory of generation now known as preformationism, which stated that offspring exist prior to conception preformed in the germ cell of one of their parents.

Format: Articles

Subject: People

Litowitz v. Litowitz [Brief] (2002)

Pursuant to an express provision of the embryo disposition contract they both signed, a husband and wife had to petition the court for instructions because they could not reach an agreement about what to do with frozen embryos when they divorced. The trial court awarded the pre-embryos to the husband and the Court of Appeals affirmed this decision. However, the Washington Supreme Court ruled that the pre-embryos should be thawed out and allowed to expire because the dispute had not been resolved within a five year time frame prescribed by the Cryopreservation Agreement.

Format: Articles

Subject: Legal, Reproduction