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James G. Wilson's Six Principles of Teratology

James Graves Wilson's six principles of teratology, published in 1959, guide research on teratogenic agents and their effects on developing organisms. Wilson's six principles were inspired by Gabriel Madeleine Camille Dareste's five principles of experimental teratology published in 1877. Teratology is the study of birth defects, and a teratogen is something that either induces or amplifies abnormal embryonic or fetal development and causes birth defects.

Format: Articles

Subject: Processes, Reproduction

James Young Simpson (1811–1870)

James Young Simpson was one of the first obstetricians to administer anesthesia during childbirth in nineteenth century Scotland. Before his work in the 1800s, physicians had few ways to reduce the pain of childbirth. Simpson experimented with the use of ether and chloroform, both gaseous chemicals, to temporarily relieve pain. He found that those chemicals both successfully inhibited the pain women felt during childbirth and pain during other surgeries. Patients under the influence of chloroform fell asleep and were unaware of the intense pain of childbirth.

Format: Articles

Subject: People

"Embryonic Stem Cell Lines Derived from Human Blastocytes" (1998), by James Thomson

After becoming chief pathologist at the University of Wisconsin-Madison Wisconsin Regional Primate Center in 1995, James A. Thomson began his pioneering work in deriving embryonic stem cells from isolated embryos. That same year, Thomson published his first paper, "Isolation of a Primate Embryonic Stem Cell Line," in Proceedings of the National Academy of Sciences of the United States of America, detailing the first derivation of primate embryonic stem cells. In the following years, Thomson and his team of scientists - Joseph Itskovitz-Eldor, Sander S. Shapiro, Michelle A.

Format: Articles

Subject: Experiments, Publications

"Experimental Studies on Congenital Malformations" (1959), by James G. Wilson

The article Experimental Studies on Congenital Malformations was published in the Journal of Chronic Diseases in 1959. The author, James G. Wilson, studied embryos and birth defects at the University of Florida Medical School in Gainesville, Florida. In his article, Wilson reviewed experiments on birds and mammals from the previous forty years to provide general principles and guidelines in the study of birth defects and teratogens, which are things that cause birth defects.

Format: Articles

Subject: Publications

Margaret Ann Bulkley (James Barry) (1789−1865)

Margaret Ann Bulkley, under the male pseudonym James Barry, was one of the first female obstetricians in early nineteenth century British Empire. She was the first person to perform a cesarean section in South Africa. Cesarean section is a procedure in which a doctor cuts into the uterus of a pregnant woman to retrieve the fetus during complicated births. Bulkley hid her gender and lived life as the male Barry to practice medicine, an opportunity not allowed to women at the time.

Format: Articles

Subject: People

James Marion Sims's Treatment of Vesico-Vaginal Fistula

James Marion Sims developed a treatment for vesico-vaginal fistulas in Montgomery, Alabama in the 1840s. Vesico-vaginal fistulas were a relatively common condition in which a woman's urine leaked into her vaginal cavity from her bladder, and many regarded the fistulas as untreatable during the early 1800s. After years of efforts to repair the fistulas with myriad tools, techniques, and procedures, Sims developed the speculum and a vaginal examination position later named for him.

Format: Articles

Subject: Technologies, Reproduction

McKeen Cattell

Format: Photographs

Subject: People

"The Role of Maternal Mitochondria during Oogenesis, Fertilization and Embryogenesis" (2002), by James M. Cummins

James M Cummins published 'The Role of Maternal Mitochondria during Oogenesis, Fertilization and Embryogenesis' 30 January 2002 in Reproductive BioMedicine Online. In the article, Cummins examines the role of the energy producing cytoplasmic particles, or organelles called mitochondria. Humans inherit mitochondria from their mothers, and mechanisms have evolved to eliminate sperm mitochondria in early embryonic development. Mitochondria contain their own DNA (mtDNA) separate from nuclear DNA (nDNA).

Format: Articles

Subject: Publications

William Harvey (1578-1657)

Renowned physician and scientist William Harvey is best known for his accurate description of how blood circulates through the body. While his published work on the circulation of blood is considered the most important of his academic life, Harvey also made significant contributions to embryology with the publication of his book Exercitationes de Generatione Animalium in 1651. In this book he established several theories that would set the stage for modern embryology and addressed many embryological issues including conception, embryogenesis, and spontaneous generation.

Format: Articles

Subject: People

Francis Harry Compton Crick (1916-2004)

Francis Harry Compton Crick, who co-discovered the structure of deoxyribonucleic acid (DNA) in 1953 in Cambridge, England, also developed The Central Dogma of Molecular Biology, and further clarified the relationship between nucleotides and protein synthesis. Crick received the Nobel Prize in Physiology or Medicine that he shared with James Watson and Maurice Wilkins in 1962 for their discovery of the molecular structure of DNA.

Format: Articles

Subject: People

"Maternal Thyroid Deficiency During Pregnancy and Subsequent Neuropsychological Development of the Child" (1999), by James E. Haddow et al.

From 1987 to the late 1990s, James Haddow and his team of researchers at the Foundation for Blood Research in Scarborough, Maine, studied children born to women who had thyroid deficiencies while pregnant with those children. Haddow's team focused the study on newborns who had normal thyroid function at the time of neonatal screening. They tested the intelligence quotient, or IQ, of the children, ages eight to eleven years, and found that all of the children born to thyroid-hormone deficient mothers performed less well than the control group.

Format: Articles

Subject: Experiments

Josef Warkany (1902–1992)

Josef Warkany studied the environmental causes of birth defects in the United States in the twentieth century. Warkany was one of the first researchers to show that factors in the environment could cause birth defects, and he helped to develop guidelines for the field of teratology, the study of birth defects. Prior to Warkany’s work, scientists struggled to explain if or how environmental agents could cause birth defects. Warkany demonstrated that a deficiency or excess of vitamin A in maternal nutrition could cause birth defects.

Format: Articles

Subject: People

Ephraim McDowell (1771-1830)

Ephraim McDowell was an US abdominal surgeon who in 1809 performed one of the first successful ovarian surgeries. McDowell conducted his medical practice in Danville, Kentucky, where he used novel methods of ovariotomy to remove a twenty-two and a half pound ovarian tumor from his patient, Jane Crawford. At the time, surgeons performed ovariotomies by making an incision into each patient’s ovary to remove a mass. However, their patients often died from infection or blood loss.

Format: Articles

Subject: People

Sidney Q. Cohlan (1915-1999)

Sidney Q. Cohlan studied birth defects in the US during the twentieth century. Cohlan helped to discover that if a pregnant woman ate too much vitamin A her fetus faced a higher than normal risk of teratogenic effects, such as cleft palate. A teratogen is a substance that causes malformation of a developing organism. Cohlan also identified the teratogenic effects of several other substances including a lack of normal magnesium and prenatal exposure to the antibiotic tetracycline.

Format: Articles

Subject: People

Induced Pluripotent Stem Cells

Induced Pluripotent Stem Cells (iPSCs) are cells derived from non-pluripotent cells, such as adult somatic cells, that are genetically manipulated so as to return to an undifferentiated, pluripotent state. Research on iPSCs, initiated by Shinya Yamanaka in 2006 and extended by James Thompson in 2007, has so far revealed the same properties as embryonic stem cells (ESCs), making their discovery potentially very beneficial for scientists and ethicists alike.

Format: Articles

Subject: Technologies

Ethics and Induced Pluripotent Stem Cells

The recent development of induced pluripotent stem cells (iPSCs) and related technologies has caught the attention of scientists, activists, politicians, and ethicists alike. IPSCs gained immediate international attention for their apparent similarity to embryonic stem cells after their successful creation in 2006 by Shinya Yamanaka and in 2007 by James Thompson and others.

Format: Articles

Subject: Technologies, Ethics

John Tyler Bonner (1920- )

The establishment and growth of developmental-evolutionary biology owes a great debt to the work of John Tyler Bonner. Bonner's studies of cellular slime molds have shed light on some of the big questions of biology including the origins of multicellularity and the nature of morphogenesis. The second child of Lilly Marguerite Stehli and Paul Bonner, John Tyler was born 12 May 1920 in New York City and spent his early years in Locust Valley, Long Island (late 1920s), France (1930), and London (1932).

Format: Articles

Subject: People

"On the Replication of Desoxyribonucleic Acid (DNA)" (1954), by Max Delbruck

In 1954 Max Delbruck published On the Replication of Desoxyribonucleic Acid (DNA) to question the semi-conservative DNA replication mechanism proposed that James Watson and Francis Crick had proposed in 1953. In his article published in the Proceedings of the National Academy of Sciences, Delbrück offers an alternative DNA replication mechanism, later called dispersive replication. Unlike other articles before it, On the Replication presents ways to experimentally test different DNA replication theories.

Format: Articles

Subject: Publications

Cold Spring Harbor Laboratory (1890- )

Cold Spring Harbor Laboratory (CSHL) is a non-profit research institution that specializes in cancer, neuroscience, plant biology, quantitative biology, and genomics. The organization is located on the shores of Cold Spring Harbor in Laurel Hollow, New York. The Brooklyn Institute of Arts and Sciences established the CSHL in 1890, to provide scientists with facilities to research Charles Darwin's evolutionary theory. The first mission of CSHL was biological science education.

Format: Articles

Subject: Organizations

"The Adaptive Significance of Temperature-Dependent Sex Determination in a Reptile" (2008), by Daniel Warner and Richard Shine

In 2008 researchers Daniel Warner and Richard Shine tested the Charnov-Bull model by conducting experiments on the Jacky dragon (Amphibolurus muricatus), in Australia. Their results showed that temperature-dependent sex determination(TSD) evolved in this species as an adaptation to fluctuating environmental temperatures. The Charnov-Bull model, proposed by Eric Charnov and James Bull in 1977, described the evolution of TSD, although the model was, for many years, untested.

Format: Articles

Subject: Experiments