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"Vietnam Veterans' Risks for Fathering Babies with Birth Defects" (1984), by J. David Erickson et al.

In 1984, J. David Erickson and his research team published the results of a study titled 'Vietnam Veterans' Risks for Fathering Babies with Birth Defects' that indicated that Vietnam veterans were at increased risk of fathering infants with serious congenital malformations, or birth defects.

Format: Articles

Subject: Publications

Warren Tay (1843–1927)

The arterial switch operation, also called the Jatene procedure, is an operation in which surgeons redirect the flow of blood through abnormal hearts. In 1975, Adib Jatene conducted the first successful arterial switch operation on a human infant. The arterial switch operation corrects a condition called transposition of the great arteries, abbreviated TGA, also called transposition of the great vessels, abbreviated TGV. TGA occurs when the pulmonary artery, which supplies deoxygenated blood to the lungs, and the aorta, which takes oxygenated blood to the body, are switched, or transposed.

Format: Articles

Subject: Technologies

St. Thomas Aquinas (c. 1225-1274)

Widely known as a key contributor to the Roman Catholic Church's body of doctrine, St. Thomas Aquinas also published an opinion on the moral status of embryos and fetuses that seems contradictory to the Catholic Church's current standpoint on the matter. Born in Naples, Italy, around 1225 (scholars debate the exact year of many of his life events) to wealthy nobility, Thomas Aquinas quickly proved himself a pious and astute scholar with an insatiable desire for logic and understanding.

Format: Articles

Subject: People, Religion

Pregnancy Tests

Throughout history methods involving urine have been a popular way to test for pregnancy. Early ideas ranged from simply observing the color of a woman's urine to the notion that the urine of pregnant women contains special crystals or secretions. Indeed, pregnancy testing can be traced back to 1350 BCE in Ancient Egypt. A written document from the time describes a process in which a woman would urinate on wheat and barley seeds over several days and, depending on which plant grew, both the woman's pregnancy status and the sex of the fetus could be determined.

Format: Articles

Subject: Technologies, Reproduction

Inducing Fertilization and Development in Sand Dollars

Sand dollars are common marine invertebrates in the phylum Echinodermata and share the same class (Echinoidea) as sea urchins. They have served as model laboratory organisms for such embryologists as Frank Rattray Lillie and Ernest Everett Just. Both Lillie and Just used Echinarachnius parma for their studies of egg cell membranes and embryo development at the Marine Biological Laboratory (MBL) at Woods Hole, Massachusetts, in the early 1900s.

Format: Articles

Subject: Processes

Advanced Cell Technology, Inc.

Advanced Cell Technology, Inc. (ACT) is a biotechnology company that uses stem cell technology to develop novel therapies in the field of regenerative medicine. Formed in 1994, ACT grew from a small agricultural cloning research facility located in Worcester, Massachusetts, into a multi-locational corporation involved in using both human embryonic stem cells (hESC) and human adult stem cells as well as animal cells for therapeutic innovations.

Format: Articles

Subject: Organizations, Reproduction

The Aschheim-Zondek Test for Pregnancy

Throughout history many different methods have been devised for the early detection of pregnancy. From the time of the Ancient Egyptians, inspection of the urine has been a popular place to start. However, it was not until the discovery of hormones in the early twentieth century that the development of truly reliable pregnancy tests occurred. Prior to 1978, when the first home pregnancy tests became available in the United States, pregnancy testing was done in hospital laboratories using various methods, one of them being the Aschheim-Zondek, or A-Z test.

Format: Articles

Subject: Technologies, 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

Tissue Engineering

Tissue engineering is a field of regenerative medicine that integrates the knowledge of scientists, physicians, and engineers into the construction or reconstruction of human tissue. Practitioners of tissue engineering seek to repair, replace, maintain, and enhance the abilities of a specific tissue or organ by means of living cells. More often than not stem cells are the form of living cells used in this technology. Tissue engineering is one of the disciplines involved in translating knowledge of developmental biology into the clinical setting.

Format: Articles

Subject: Processes

Ernst Heinrich Philipp August Haeckel (1834-1919)

Ernst Heinrich Philipp August Haeckel was a prominent comparative anatomist and active lecturer in the late nineteenth and early twentieth centuries. He is most well known for his descriptions of phylogenetic trees, studies of radiolarians, and illustrations of vertebrate embryos to support his biogenetic law and Darwin's work with evolution. Haeckel aggressively argued that the development of an embryo repeats or recapitulates the progressive stages of lower life forms and that by studying embryonic development one could thus study the evolutionary history of life on earth.

Format: Articles

Subject: People

45 CFR 46: Protection of Human Subjects under United States Law (1974)

In the United States, the Code of Federal Regulations Title 45: Public Welfare, part 46 (45 CFR 46) provides protection for human subjects in research carried out or supported by most federal departments and agencies. 45 CFR 46 created a common federal policy for the protection of such human subjects that was accepted by the Office of Science and Technology Policy and issued by each of the departments and agencies listed in the document.

Format: Articles

Subject: Legal

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

Hematopoietic Stem Cell Transplantation

The purpose of regenerative medicine, especially tissue engineering, is to replace damaged tissue with new tissue that will allow the body to resume normal function. The uniqueness of tissue engineering is that it can restore normal structure in addition to repairing tissue function, and is often accomplished using stem cells. The first type of tissue engineering using stem cells was hematopoietic stem cell transplantation (HSCT), a surgical procedure in which hematopoietic stem cells (HSCs) are infused into a host to treat a variety of blood diseases, cancers, and immunodeficiencies.

Format: Articles

Subject: Technologies

The Source-Sink Model

The source-sink model, first proposed by biologist Francis Crick in 1970, is a theoretical system for how morphogens distribute themselves across small fields of early embryonic cells. A morphogen is a substance that determines the fate and phenotype of a group of cells through a concentration gradient of itself across that group. Crick’s theory has been experimentally confirmed with several morphogens, most notably with the protein bicoid , the first discovered morphogen. The model provides a theoretical structure for the understanding of some features of early embryonic development.

Format: Articles

Subject: Theories

The Marine Biological Laboratory

The Marine Biological Laboratory (MBL) was founded in 1888 in Woods Hole, Massachusetts. Woods Hole was already the site for the government 's US Fish Commission Laboratory directed by Spencer Fullerton Baird, and it seemed like the obvious place to add an independent research laboratory that would draw individual scientific investigators along with students and instructors for courses.

Format: Articles

Subject: Organizations

Dickey-Wicker Amendment, 1996

The Dickey-Wicker Amendment is an amendment attached to the appropriations bills for the Departments of Health and Human Services, Labor, and Education each year since 1996 restricting the use of federal funds for creating, destroying, or knowingly injuring human embryos. The Dickey-Wicker Amendment began as a rider (another name for an amendment) attached to House Resolution (H.R.) 2880. H.R.

Format: Articles

Subject: Legal

"Visualizing Human Embryos" (1999), by Bradley Richard Smith

In March 1999 Bradley Richard Smith, a professor at the University of Michigan, unveiled the first digital magnetic resonance images of human embryos. In his article "Visualizing Human Embryos for Scientific American," Smith displayed three-dimensional images of embryos using combinations of Magnetic Resonance Microscopy (MRM), light microscopy, and various computer editing. He created virtual embryo models that it is possible to view as dissections, animations, or in their whole 3D form. Smith's images constitute a new way of visualizing embryos.

Format: Articles

Subject: Outreach, Publications

"Behavioral Thermoregulation by Turtle Embryos" (2011), by Wei-Guo Du, Bo Zhao, Ye Chen, and Richard Shine

In "Behavioral Thermoregulation by Turtle Embryos," published in Proceedings of the National Academy of Sciences in April, 2011, Wei-Guo Du, Bo Zhao, Ye Chen, and Richard Shine report that turtle embryos can move towards warmer temperatures within the egg when presented with a small, 0.8 degrees Celsius gradient. This behavioral thermoregulation may benefit the embryo's fitness by accelerating the rate of development enough to decrease the incubation period by up to four and a half days. Embryos are generally thought to have little control over their surroundings.

Format: Articles

Subject: Publications

The inductive capacity of oral mesenchyme and its role in tooth development (1969-1970), by Edward J. Kollar and Grace R. Baird

Between February 1969 and August 1970 Edward Kollar and Grace Baird, from the University of Chicago in Chicago, Illinois, published three papers that established the role of the mesenchyme in tooth induction. Drawing upon a history of using tissue interactions to understand differentiation, Kollar and Baird designed their experiments to understand how differentiated structures become specified. Their work overturned a widely accepted model that epithelium controls the identity of the structure, a phenomenon called structural specificity.

Format: Articles

Subject: Experiments

"The Cell-Theory" (1853), by Thomas Henry Huxley

The Cell-Theory was written by Thomas Henry Huxley in Britain and published in 1853 by The British and Foreign Medico-Chirurgical Review. The twenty-two page article reviews twelve works on cell theory, including those in Germany by Caspar Friedrich Wolff in the eighteenth century and by Karl Ernst von Baer in the nineteenth century. Huxley spends much of The Cell-Theory on a cell theory proposed in the late 1830s by Matthias Schleiden and Theodor Schwann in Germany.

Format: Articles

Subject: Publications

Edward Donnall Thomas (1920-2012)

Edward Donnall Thomas, an American physician and scientist, gained recognition in the scientific community for conducting the first bone marrow transplant, a pioneering form of hematopoietic stem cell transplantation (HSCT). Bone marrow transplants are considered to be the first successful example of tissue engineering, a field within regenerative medicine that uses hematopoietic stem cells (HSCs) as a vehicle for treatment. Prior to Thomas's groundbreaking work, most blood-borne diseases, including certain inherited and autoimmune diseases, were considered lethal.

Format: Articles

Subject: People

Embryonic Sex Differentiation and Sex Hormones (1947), by Carl R. Moore

In 1947, Carl Richard Moore, a researcher at the University of Chicago, in Chicago, Illinois, wrote Embryonic Sex Differentiation and Sex Hormones, which was published in the same year as a first-edition monograph. In the book, Moore argues that regulation of sex differentiation in mammals is not controlled by sex hormones secreted by embryonic sex organs (gonads), but is controlled by non-hormonal genetic factors.

Format: Articles

Subject: Publications, Experiments

Andrew Francis Dixon (1868-1936)

Andrew Francis Dixon studied human anatomy and egg cells at the turn of the twentieth century in Ireland and Great Britain. Dixon studied the sensory and motor nervous system of the face, the cancellous bone tissue of the femur, supernumerary kidneys, and the urogenital system. In 1927 Dixon described a mature human ovarian follicle. This follicle, Dixon noted, contained an immature human egg cell (oocyte) with a visible first polar body and the beginnings of the second polar body.

Format: Articles

Subject: People

Paul Kammerer's Experiments on the Midwife Toad (1905-1910)

In the first decade of the twentieth century, Paul Kammerer, a zoologist working at the Vivarium in Vienna, Austria, conducted research on developmental mechanisms, including a series of breeding experiments on toads (Alytes obstetricans). Kammerer claimed that his results demonstrated that organisms could transmit acquired characteristics to their offspring.

Format: Articles

Subject: Experiments

NovaSure Endometrial Ablation

NovaSure is a device for endometrial ablation, which is a procedure that removes the endometrium, that the US Food and Drug Administration, or FDA, approved for use on 28 September 2001. Endometrium is the tissue that lines the uterus. NovaSure destroys the endometrium by sending electric beams at the endometrium. Hologic, a medical technology company concerned with women’s health, developed NovaSure to treat menorrhagia, or heavy bleeding during menstruation. Menorrhagia is a common symptom of endometriosis. Endometriosis is the growth of the endometrium outside of the uterus.

Format: Articles

Subject: Technologies