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"Versuche zur Analyse der Induktionsmittel in der Embryonalentwicklung" (1932), by Hermann Bautzmann, Johannes Holtfreter, Otto Mangold, and Hans Spemann

In "Versuche zur Analyse der Induktionsmittel in der Embryonalentwicklung," published in Naturwissenschaften in 1932, Hermann Bautzmann, Johannes Holtfreter, Otto Mangold, and Hans Spemann jointly reported on experiments each had conducted testing the activity of organizers killed by boiling, freezing, alcohol, and drying. Each of the authors had been independently conducting similar experiments, when Holtfreter made a breakthrough allowing him to produce many more successful transplantations.

Format: Articles

Subject: Experiments

"Experiments on Embryonic Induction III. A Note on Inductions by Chick Primitive Streak Transplanted to the Rabbit Embryo" (1934), by Conrad Hal Waddington

Conrad Hal Waddington's "Experiments on Embryonic Induction III," published in 1934 in the Journal of Experimental Biology, describes the discovery that the primitive streak induces the mammalian embryo. Waddington's hypothesis was that a transplanted primitive streak could induce neural tissue in the ectoderm of the rabbit embryo. The primitive streak defines the axis of an embryo and is capable of inducing the differentiation of various tissues in a developing embryo during gastrulation.

Format: Articles

Subject: Experiments

Hilde Mangold (1898-1924)

Hilde Mangold, previously Hilde Proescholdt, was a German embryologist and physiologist who became well known for research completed with Hans Spemann in the 1920s. As a graduate student, Mangold assisted Spemann and together they discovered and coined the term the "organizer." The organizer discovery was a crucial contribution to embryology that led to further understanding of the pattern of embryo differentiation of amphibians.

Format: Articles

Subject: People

Otto Mangold (1891-1962)

Otto Mangold was an early twentieth century embryologist who specialized in the development of amphibian embryos. A major emphasis of his research was refining the concept of the organizer, now referred to as embryonic induction. He was born on 4 November 1891 in Auenstein, Germany, and came from what Viktor Hamburger, a colleague and personal acquaintance, described as "peasant stock." Mangold attended several universities including Tübingen, Freiburg, and Rostock.

Format: Articles

Subject: People

Johannes Holtfreter (1901-1992)

Johannes Holtfreter made important discoveries about the properties of the organizer discovered by Hans Spemann. Although he spent much time away from the lab over many years, he was a productive researcher. His colleagues noted that the time he spent away helped revitalize his ideas. He is credited with the development of a balanced salt medium to allow embryos to develop; the discovery that dead organizer tissue retains inductive abilities; and the development of specification, competence, and distribution of fate maps in the developing frog embryo.

Format: Articles

Subject: People

"Testing the Kin Selection Theory: Who Controls the Investments?" from The Ants (1990), by Bert Hölldobler and Edward O. Wilson

In “Testing the Kin Selection Theory: Who Controls the Investments?” Bert Hölldobler and Edward Osborne Wilson discussed the predictive power of kin selection theory, a theory about the evolution of social behaviors. As part of Hölldobler's and Wilson's 1990 book titled The Ants, Hölldobler and Wilson compared predictions about the reproductive practices of ants to data about the reproductive practices of ants. They showed that the data generally supported the expected behaviors proposed by kin selection theory.

Format: Articles

Subject: Publications, Theories

Elinor Catherine Hamlin (1924- )

Elinor Catherine Hamlin founded and helped fund centers in Ethiopia to treat women affected by fistulas from obstetric complications. Obstetric fistulas develop in women who experience prolonged labor, as the pressure placed on the pelvis by the fetus during labor causes a hole, or fistula, to form between the vagina and the bladder (vesicovaginal fistula) or between the vagina and the rectum (rectovaginal fistula). Both of those conditions result in urinary or fecal incontinence, which often impacts womenÍs social status within their communities.

Format: Articles

Subject: People, Reproduction

Clinical Tests of Estrogen Injections on Women with Abnormal Menstrual Cycles During the Early 1920s by Jean Paul Pratt and Edgar Allen

In the early twentieth century US, Jean Paul Pratt and Edgar Allen conducted clinical experiments on women who had abnormal menstrual cycles. During the clinical tests, researchers injected the hormone estrogen into their patients to alleviate their menstrual ailments, which ranged from irregular cycles to natural menopause. The hormone estrogen plays a prominent role in the menstrual cycle by signaling the tissue lining the uterus (endometrium) to thicken in preparation for possible pregnancy.

Format: Articles

Subject: Experiments

Emma Goldman (1869–1940)

Emma Goldman was a traveling public speaker and writer known for her anarchist political views as well as her opinions on contraception and birth limiting in the late nineteenth century in the United States. Goldman identified as an anarchist, which she explained as being part of an ideology in which people use violence to provoke or demand social and political change. Goldman was involved in many anarchist social groups and published the anarchist magazine Mother Earth.

Format: Articles

Subject: People

Karl Oskar Illmensee (1939–)

Karl Oskar Illmensee studied the cloning and reproduction of fruit flies, mice, and humans in the US and Europe during the twentieth and twenty-first centuries. Illmensee used nuclear transfer techniques (cloning) to create early mouse embryos from adult mouse cells, a technique biologists used in later decades to help explain how embryonic cells function during development. In the early 1980s, Illmensee faced accusations of fraud when others were unable to replicate the results of his experiments with cloned mouse embryos.

Format: Articles

Subject: People, People

Tucson Woman's Clinic v. Eden (2004)

The case Tucson Woman's Clinic v. Eden (2004) established that some of Arizona's abortion clinic laws violated physicians' and patients' rights to privacy, and it required those laws to be rewritten. The laws required most abortion providers to be licensed with the Arizona Department of Health Services and to submit to all the regulations the Department established for abortion clinics. The regulations allowed the state to search abortion clinics without warrants and to access patient records and ultrasound prints, among other provisions.

Format: Articles

Subject: Legal, Reproductive Health Arizona

Roe v. Wade (1973)

In the 1973 case of Roe v. Wade, the US Supreme Court ruled that laws banning abortion violated the US Constitution. The Texas abortion laws, articles 1191–1194, and 1196 of the Texas penal code, made abortion illegal and criminalized those who performed or facilitated the procedure. Prior to Roe v. Wade, most states heavily regulated or banned abortions. The US Supreme Court decision in Roe v. Wade secured women's rights to terminate pregnancies for any reasons within the first trimester of pregnancy.

Format: Articles

Subject: Legal, Reproduction

Lydia Pinkham’s Vegetable Compound (1873-1906)

First marketed in the US 1875, Lydia Pinkham’s Vegetable Compound was an herbal medicine used by women to relieve menstrual discomfort and menopausal symptoms in women. The herbal compound was invented by Lydia Estes Pinkham in 1873 in her home kitchen in Lynn, Massachusetts. Pinkham created the compound by mixing alcohol with roots and herbs. The compound was patented, packaged, and distributed by the Mrs. Lydia Pinkham Medicine Company in 1876. The Mrs.

Format: Articles

Subject: Technologies, Reproduction

Min Chueh Chang (1908-1991)

As one of the researchers involved in the development of the oral contraceptive pill, Min Chueh Chang helped to revolutionize the birth control movement. Although best known for his involvement with "the pill," Chang also made a number of discoveries throughout his scientific career involving a range of topics within the field of reproductive biology. He published nearly 350 articles in scientific journals.

Format: Articles

Subject: People, Reproduction

US Endocrine Disruptor Screening Program

In 1996, the US Congress mandated that the US Environmental Protection Agency (EPA) create and regulate the Endocrine Disruptor Screening Program. The program tests industrial and agricultural chemicals for hormonal impacts in humans and in wildlife that may disrupt organisms' endocrine systems. The endocrine system regulates the release of small amounts of chemical substances called hormones to keep the body functioning normally.

Format: Articles

Subject: Disorders, Legal, Ethics

Robert Geoffrey Edwards's Study of Fertilization of Human Oocytes Matured in vitro, 1965 to 1969

Robert Geoffrey Edwards, a British developmental biologist at University of Cambridge, began exploring human in vitro fertilization (IVF) as a way to treat infertility in 1960. After successfully overcoming the problem of making mammalian oocytes mature in vitro in 1965, Edwards began to experiment with fertilizing matured eggs in vitro. Collaborating with other researchers, Edwards eventually fertilized a human egg in vitro in 1969. This was a huge step towards establishing human IVF as a viable fertility treatment.

Format: Articles

Subject: Experiments, Reproduction

A. Z. v. B. Z. (2000)

In A.Z. v. B.Z. (2000), the Supreme Judicial Court of Massachusetts in Boston, Massachusetts, affirmed a lower courtÕs decision, ruling that contracts that require a party to become a parent against his or her will are unenforceable and contrary to public policy. The case centered around A.Z. and B.Z., a divorced couple who had previously used in vitro fertilization (IVF) to start a family together during their marriage and had several preembryos cryopreserved as part of the process.

Format: Articles

Subject: Legal

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

Aristotle (384-322 BCE)

Aristotle studied developing organisms, among other things, in ancient Greece, and his writings shaped Western philosophy and natural science for greater than two thousand years. He spent much of his life in Greece and studied with Plato at Plato's Academy in Athens, where he later established his own school called the Lyceum. Aristotle wrote greater than 150 treatises on subjects ranging from aesthetics, politics, ethics, and natural philosophy, which include physics and biology. Less than fifty of Aristotle's treatises persisted into the twenty-first century.

Format: Articles

Subject: People

David Michael Rorvik (1944–)

David Michael Rorvik is a science journalist who publicized advancements in the field of reproductive medicine during the late twentieth century. Rorvik wrote magazine articles and books in which he discussed emerging methods and technologies that contributed to the progression of reproductive health, including sex determination, in vitro fertilization, and human cloning. During that time, those topics were controversial and researchers often questioned Rorvik’s work for accuracy.

Format: Articles

Subject: People

"Altruism and the Origin of the Worker Caste" from The Ants (1990), by Bert Hölldobler and Edward Osborne Wilson

In 'Altruism and the Origin of the Worker Caste,' Bert Hölldobler and Edward Osborne Wilson explore the evolutionary origins of worker ants. 'Altruism and the Origin of the Worker Caste' is the fourth chapter of Hölldobler and Wilson's book, The Ants, which was published by The Belknap Press of Harvard University in Cambridge, Massachusetts, in 1990. In 'Altruism and the Origin of the Worker Caste,' Hölldobler and Wilson evaluate various explanations for how a non-reproductive caste of ant evolved.

Format: Articles

Subject: Publication

Life's Greatest Miracle (2001), by Julia Cort and NOVA

The Public Broadcasting Station (PBS) documentary Life's Greatest Miracle (abbreviated Miracle, available at http://www.pbs.org/wgbh/nova/miracle/program.html), is arguably one of the most vivid illustrations of the making of new human life. Presented as part of the PBS television series NOVA, Miracle is a little less than an hour long and was first aired 20 November 2001. The program was written and produced by Julia Cort and features images by renowned Swedish photographer Lennart Nilsson.

Format: Articles

Subject: Outreach, Reproduction

Clomiphene Citrate

Clomiphene citrate, more commonly known by its brand names Clomid and Serophene, is a medication prescribed to women to stimulate ovulation in order to treat infertility. It stimulates ovulation in women who do not ovulate or ovulate irregularly. This drug was created by Dr. Frank Palopoli in 1956 while he worked for Merrell Company. It first successfully induced ovulation in women in 1961 and was approved by the Federal and Drug Administration (FDA) in 1967.

Format: Articles

Subject: Technologies

Robert Geoffrey Edwards's Study of in vitro Mammalian Oocyte Maturation, 1960 to 1965

In a series of experiments between 1960 and 1965, Robert Geoffrey Edwards discovered how to make mammalian egg cells, or oocytes, mature outside of a female's body. Edwards, working at several research institutions in the UK during this period, studied in vitro fertilization (IVF) methods. He measured the conditions and timings for in vitro (out of the body) maturation of oocytes from diverse mammals including mice, rats, hamsters, pigs, cows, sheep, and rhesus monkeys, as well as humans.

Format: Articles

Subject: Experiments, Reproduction

Retinoids As Teratogens

Vitamin A (retinol) is an essential vitamin in the daily functioning of human beings that helps regulate cellular differentiation of epithelial tissue. Studies have shown that an excess of vitamin A can affect embryonic development and result in teratogenesis, or the production of birth defects in a developing embryo. Excess intake of vitamin A and retinoids by pregnant women often results malformations to fetuses' skulls, faces, limbs, eyes, central nervous system.

Format: Articles

Subject: Disorders, Reproduction