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Methylmercury and Human Embryonic Development

Methylmercury (MeHg) is an organic form of mercury that can damage the developing brains of human fetuses. Women who consume methylmercury during pregnancy can bear children who have neurological issues because methylmercury has toxic effects on the nervous system during embryonic development. During the third week of gestation, the human nervous system begins to form in the embryo. During this gestational period, the embryo's nervous system is particularly susceptible to the influence of neurotoxins like methylmercury that can result in abnormalities.

Format: Articles

Subject: Reproduction, Disorders

Rosalyn Sussman Yalow (1921-2011)

Rosalyn Sussman Yalow co-developed the radioimmunoassay (RIA), a method used to measure minute biological compounds that cause immune systems to produce antibodies. Yalow and research partner Solomon A. Berson developed the RIA in the early 1950s at the Bronx Veterans Administration (VA) Hospital, in New York City, New York. Yalow and Berson's methods expanded scientific research, particularly in the medical field, and contributed to medical diagnostics. For this achievement, Yalow received the Nobel Prize in Physiology or Medicine in 1977.

Format: Articles

Subject: People

Stem Cells

According to the US National Institutes of Health (NIH), the standard American source on stem cell research, three characteristics of stem cells differentiate them from other cell types: (1) they are unspecialized cells that (2) divide for long periods, renewing themselves and (3) can give rise to specialized cells, such as muscle and skin cells, under particular physiological and experimental conditions. When allowed to grow in particular environments, stem cells divide many times. This ability to proliferate can yield millions of stem cells over several months.

Format: Articles

Subject: Processes

Kass v. Kass (1998)

In Maureen Kass v. Steven Kass (1998), the Court of Appeals of New York in Albany, New York, ruled that the state should generally consider IVF consent forms signed by participants in an in vitro fertilization (IVF) program valid, binding, and enforceable in the event of a dispute. The court indicated that decisions regarding the handling of cryopreserved pre-zygotes, often called preembryos, contained within these consent forms should be upheld.

Format: Articles

Subject: Legal

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

Regeneration

Regeneration is a fascinating phenomenon. The fact that many organisms have the capacity to regenerate lost parts and even remake complete copies of themselves is difficult to fathom; so difficult, in fact, that for a very long time people were reluctant to believe regeneration actually took place. It seemed unbelievable that some organisms could re-grow lost limbs, organs, and other body parts. If only we could do the same!

Format: Articles

Subject: Processes

In the Womb: Identical Twins (2009), by National Geographic

National Geographic's documentary In the Womb: Identical Twins focuses on the prenatal development of human identical twins. Director Lorne Townend uses three-dimensional (3D) and four-dimensional (4D) ultrasound imaging and microscopy to depict twin development , genetic and epigenetic variations in the fetuses, and methods of fetal survival in the confines of the womb. Artist renditions of scientific data fill in areas of development inaccessible to the imaging tools.

Format: Articles

Subject: Outreach, Reproduction

Teratomas

Teratomas are embryonal tumors that normally arise from germ cells and are typically benign. They are defined as being composed either of tissues that are foreign to the area in which they form, or of tissues that derive from all three of the germ layers. Malignant teratomas are known as teratocarcinomas; these cancerous growths have played a pivotal role in the discovery of stem cells. "Teratoma" is Greek for "monstrous tumor"; these tumors were so named because they sometimes contain hair, teeth, bone, neurons, and even eyes.

Format: Articles

Subject: Processes, Disorders

Carnegie Institution of Washington Department of Embryology

The Carnegie Institution of Washington's (CIW) Embryology Department was opened in 1914 and remains one of six departments in the CIW. The department quickly became, and remains, world renowned for its many embryonic development discoveries. In 1913 Franklin P. Mall, Professor of Anatomy at Johns Hopkins Medical School, applied for a Carnegie grant to support his research with human embryos. Mall had a collection of over 800 human embryo specimens and was at the point of wanting to do more than just collect.

Format: Articles

Subject: Organizations

Nerve Growth Factor

Nerve growth factor (NGF) is a signaling protein and growth factor implicated in a wide range of development and maintenance functions. NGF was discovered through a series of experiments in the 1950s on the development of the chick nervous system. Since its discovery, NGF has been found to act in a variety of tissues throughout development and adulthood. It has been implicated in immune function, stress response, nerve maintenance, and in neurodegenerative diseases.

Format: Articles

Subject: Processes

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

Images of Embryos in Life Magazine in the 1950s

Embryonic images displayed in Life magazine during the mid-twentieth century serve as a representation of technological advances and the growing public interest in the stages of embryological development. These black-and-white photographs portray skeletal structures and intact bodies of chicken embryos and human embryos and fetuses obtained from collections belonging to universities and medical institutions.

Format: Articles

Subject: Outreach, Publications, Reproduction

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

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

Intracytoplasmic Sperm Injection

Intracytoplasmic Sperm Injection (ICSI) is an assisted reproductive technique (ART) initially developed by Dr. Gianpiero D. Palermo in 1993 to treat male infertility. It is most commonly used in conjunction with in vitro fertilization (IVF) or a less commonly used technique called zygote intrafallopian transfer (ZIFT). In natural fertilization, the sperm must penetrate the surface of the female egg, or oocyte.

Format: Articles

Subject: Technologies, Reproduction

Ziegler Wax Embryo Models

Three-dimensional anatomical models have long been essential to the learning of science and lend a sense of "control" to those practicing in the field. As the development of embryology grew in importance during the late 1800s, so did the need for models to show intricate details of embryos.

Format: Articles

Subject: Technologies, Reproduction

Enovid: The First Hormonal Birth Control Pill

Enovid was the first hormonal birth control pill. G. D. Searle and Company began marketing Enovid as a contraceptive in 1960. The technology was created by the joint efforts of many individuals and organizations, including Margaret Sanger, Katharine McCormick, Gregory Pincus, John Rock, Syntex, S.A. Laboratories, and G.D. Searle and Company Laboratories.

Format: Articles

Subject: Technologies, Reproduction

The Eugenics Record Office at Cold Spring Harbor Laboratory (1910-1939)

From its founding in 1910 until it closed its doors in 1939, the Eugenics Record Office (ERO) at Cold Spring Harbor Laboratory in New York was the center of the American Eugenics Movement. Charles Davenport, a geneticist and biologist, founded the ERO, and served as its director until 1934. Under the direction of Davenport and his associate, superintendant Harry H. Laughlin, the influence of the ERO on science and public policy waxed during the early twentieth century until after World War II.

Format: Articles

Subject: Organizations, Reproduction

Zhang Lizhu (1921- )

Zhang Lizhu is a Chinese gynecologist and researcher. For most of her career, she worked in the Peking Medical College Third Hospital, renamed in 2000, Peking University Third Hospital. There, she led a team of researchers and physicians in the study of human in vitro fertilization (IVF) and embryo transfer (ET) technology. Zhang and her colleagues contributed to the birth of the first test-tube baby in Mainland China in 1988.

Format: Articles

Subject: People, Reproduction

The Effects of Bisphenol A on Embryonic Development

Bisphenol A (BPA) is an organic compound that was first synthesized by Aleksandr Dianin, a Russian chemist from St. Petersburg, in 1891. The chemical nomenclature of BPA is 2,2-bis (4-hydroxyphenyl) propane. The significance of this synthesized compound did not receive much attention until 1936, when two biochemists interested in endocrinology, Edward Dodds and William Lawson, discovered its ability to act as an estrogen agonist in ovariectomized, estrogen-deficient rats.

Format: Articles

Subject: Disorders, Reproduction

Johns Hopkins Fertility Center

Johns Hopkins Medical Center, located in Baltimore, Maryland, opened in 1889; its associated medical school opened four years later. Today the hospital, a leading research center, contains many departments, including a fertility center that is renowned for taking on difficult cases that have been rejected by other fertility clinics. The fertility center was founded by physician Georgeanna Seegar Jones in 1939 as the Division of Reproductive Endocrinology in the gynecology department. The division expanded once formal training in reproductive endocrinology began in 1973.

Format: Articles

Subject: Organizations, Reproduction

Hysterectomy

A hysterectomy is the surgical removal of a woman's uterus. For many women, a hysterectomy comes as a solution to health problems as diverse as abnormal bleeding to reproductive cancers. First performed in the early 1800s, this procedure has evolved in terms of both technique and popularity. The first successful abdominal hysterectomy was performed by Ellis Burnham in Lowell, Massachusetts, in 1853, although earlier attempts were made in the 1840s.

Format: Articles

Subject: Technologies, Reproduction

Endoscopy

Endoscopy is a medical procedure that enables the viewing and biopsy of, and surgery on, internal tissues and organs. Endoscopic examinations are characterized by the introduction of a tube containing a series of lenses into the body through either an incision in the skin or a natural opening or cavity. During the mid-twentieth century, photographer Lennart Nilsson used endoscopes to capture the now-familiar images of embryos and fetuses.

Format: Articles

Subject: Technologies, Reproduction

Conjoined Twins

Conjoined twins are twins whose bodies are anatomically joined in utero. The degree to which the twins are attached can range from simple, involving skin and cartilage, to complex, including fusion of the skull(s), brain(s), or other vital organs. There are more than a dozen classifications of conjoined twins but what they all tend to have in common is the sharing of the chorion, placenta, and amniotic sac.

Format: Articles

Subject: Disorders, Reproduction

Diprosopus (Craniofacial Duplication)

Diprosopus is a congenital defect also known as craniofacial duplication. The exact description of diprosopus refers to a fetus with a single trunk, normal limbs, and facial features that are duplicated to a certain degree. A less severe instance is when the nose is duplicated and the eyes are spaced far apart. In the most extreme instances, the entire face is duplicated, hence the name diprosopus, which is Greek for two-faced. Fetuses with diprosopus often also lack brains (anencephaly), have neural tube defects, or heart malformations.

Format: Articles

Subject: Disorders, Reproduction