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Spemann-Mangold Organizer

The Spemann-Mangold organizer, also known as the Spemann organizer, is a cluster of cells in the developing embryo of an amphibian that induces development of the central nervous system. Hilde Mangold was a PhD candidate who conducted the organizer experiment in 1921 under the direction of her graduate advisor, Hans Spemann, at the University of Freiburg in Freiburg, German. The discovery of the Spemann-Mangold organizer introduced the concept of induction in embryonic development.

Format: Articles

Subject: Processes

Endoderm

Endoderm is one of the germ layers-- aggregates of cells that organize early during embryonic life and from which all organs and tissues develop. All animals, with the exception of sponges, form either two or three germ layers through a process known as gastrulation. During gastrulation, a ball of cells transforms into a two-layered embryo made of an inner layer of endoderm and an outer layer of ectoderm. In more complex organisms, like vertebrates, these two primary germ layers interact to give rise to a third germ layer, called mesoderm.

Format: Articles

Subject: Processes

A Toolkit for Integrating Menstrual Hygiene Management (MHM) into Humanitarian Response (2017), by Marni Sommer, Margaret Schmitt, and David Clatworthy

In October 2017, Columbia University Mailman School of Public Health in New York City, New York, and the International Rescue Committee published A Toolkit for Integrating Menstrual Hygiene Management (MHM) into Humanitarian Response. Researchers Marni Sommer, Margaret Schmitt, and David Clatworthy collaborated on the Toolkit to benefit women and girls in Lebanon, Myanmar, and Tanzania. The Toolkit serves as a guideline for humanitarian organizations to ensure better menstrual hygiene management, or MHM, in low and middle-income countries.

Format: Articles

Subject: Publications

Rock-Menkin Experiments

Dr. John Rock, a doctor of obstetrics and gynecology in Boston, and Miriam Menkin, Rock s hired lab technician, were the first researchers to fertilize a human egg outside of a human body in February of 1944. Their work was published on 4 August 1944 in an issue of Science in an article entitled "In Vitro Fertilization and Cleavage of Human Ovarian Eggs." This experiment marked the first time in history that a human embryo was produced outside of the human body, proving that in vitro fertilization was possible in humans.

Format: Articles

Subject: Experiments, Reproduction

Facial Abnormalities of Fetal Alcohol Syndrome (FAS)

Prenatal exposure to alcohol (ethanol) results in a continuum of physical, neurological, behavioral, and learning defects collectively grouped under the heading Fetal Alcohol Spectrum Disorder (FASD). Fetal Alcohol Syndrome (FAS) was first defined in 1973 as a condition characterized by pre- and postnatal growth deficiencies, facial abnormalities, and defects of the central nervous system. The pattern of facial defects that occur as a result of ethanol exposure during development primarily affects the midline of the face, altering morphology of the eyes, nose, and lips.

Format: Articles

Subject: Disorders, Reproduction

Spermism

Spermism was one of two models of preformationism, a theory of embryo generation prevalent in the late seventeenth through the end of the eighteenth century. Spermist preformationism was the belief that offspring develop from a tiny fully-formed fetus contained within the head of a sperm cell. This model developed slightly later than the opposing ovist model because sperm cells were not seen under the microscope until about 1677.

Format: Articles

Subject: Theories

Hermann Joseph Muller (1890-1967)

Hermann Joseph Muller studied the effects of x-ray radiation on genetic material in the US during the twentieth century. At that time, scientists had yet to determine the dangers that x-rays presented. In 1927, Muller demonstrated that x-rays, a form of high-energy radiation, can mutate the structure of genetic material. Muller warned others of the dangers of radiation, advising radiologists to protect themselves and their patients from radiation. He also opposed the indiscriminate use of radiation in medical and industrial fields.

Format: Articles

Subject: People

Fetus in Fetu

Fetus in fetu is a rare variety of parasitic twins , where the developmentally abnormal parasitic twin is completely encapsulated within the torso of the otherwise normally developed host twin. In the late eighteenth century, German anatomist Johann Friedrich Meckel was the first to described fetus in fetu, which translates to “fetus within fetus.” Fetus in fetu is thought to result from the unequal division of the totipotent inner cell mass , the mass of cells that is the ancestral precursor to all cells in the body.

Subject: Theories, Disorders, Reproduction

Franklin William Stahl (1929– )

Franklin William Stahl studied DNA replication, bacteriophages, and genetic recombination in the US during the mid-twentieth and early twenty-first centuries. With his colleague Matthew Meselson, Stahl performed an experiment called the Meselson-Stahl experiment, which provided evidence for a process called semi-conservative DNA replication. Semi-conservative replication is a process in which each strand of a parental DNA double helix serves as a template for newly replicated daughter strands, so that one parental strand is conserved in every daughter double helix.

Format: Articles

Subject: People

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

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

Chemical Induction

Research in chemical induction seeks to identify the compound or compounds responsible for differentiation in a developing embryo. Soren Lovtrup compared the search for these compounds to the search for the philosopher's stone. It was based on the assumption that the differentiating agents have to be chemical substances either within cells or in the extracellular matrix.

Format: Articles

Subject: Processes

Dizhou Tong (1902-1979)

Dizhou Tong, also called Ti Chou Tung, studied marine animals and helped introduce and organize experimental embryology in China during the twentieth century. He introduced cellular nuclear transfer technology to the Chinese biological community, developed methods to clone organisms from many marine species, and investigated the role of cytoplasm in early development. Tong's administrative and scientific leadership in the fields of marine, cellular, and developmental biology contributed to China's experimental embryology research programs.

Format: Articles

Subject: People

Benjamin Harrison Willier (1890-1972)

Benjamin Harrison Willier is considered one of the most versatile embryologists to have ever practiced in the US. His research spanned most of the twentieth century, a time when the field of embryology evolved from being a purely descriptive pursuit to one of experimental research, to that of incorporating molecular biology into the research lab. Willier was born on 2 November 1890 near Weston, Ohio to Mary Alice Ricard. He spent his childhood doing farming chores and running the farm while his father, David Willier worked as a banker.

Format: Articles

Subject: People

"Reproductive Options for HIV-Serodiscordant Couples” (2006) by Pablo Barreiro, Ann Duerr, Karen Beckerman, and Vincent Soriano

In July 2006, scientist Pablo Barreiro and colleagues published “Reproduction Options for HIV-Serodiscordant Couples,” in which they recommended methods for human immunodeficiency virus, or HIV, serodiscordant couples to procreate. An HIV-serodiscordant couple is one in which one partner is HIV-positive, meaning they carry HIV, and the other is HIV-negative, meaning they do not carry the virus. HIV is a virus that can spread by sexual contact and it attacks the immune system, causing a person with the virus to have weakened responses to illnesses.

Format: Articles

Subject: Publications

Theophilus Shickel Painter (1889-1969)

Theophilus Shickel Painter studied the structure and
function of chromosomes in the US during in the early to mid-twentieth century. Painter worked at
the University of Texas at Austin in Austin, Texas. In the 1920s
and 1930s, Painter studied the chromosomes of the salivary gland
giant chromosomes of the fruit fly (Drosophila
melanogaster), with Hermann J. Muller. Muller and Painter
studied the ability of X-rays to cause changes in the chromosomes
of fruit flies. Painter also studied chromosomes in mammals.

Format: Articles

Subject: People

Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Gene

The Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene was identified in 1989 by geneticist Lap-Chee Tsui and his research team as the gene associated with cystic fibrosis (CF). Tsui's research pinpointed the gene, some mutations to which cause CF, and it revealed the underlying disease mechanism. The CFTR gene encodes a protein in the cell membrane in epithelial tissues and affects multiple organ systems in the human body. Mutations in the CFTR gene cause dysfunctional regulation of cell electrolytes and water content.

Format: Articles

Subject: Disorders, Reproduction

Ovum Humanum: Growth, Maturation, Nourishment, Fertilization and Early Development (1960), by Landrum Brewer Shettles

Ovum Humanum was written and compiled by Dr. Landrum Brewer Shettles while he worked as a doctor in New York. The publication contains an atlas of photographs of the human egg cell that Shettles took while working at Columbia Presbyterian Hospital in New York City. Stechert-Hafner, Inc, a publishing company based in New York City, published the book in 1960. The book presents a collection of color photographs that shows detail of the human egg that had never been seen before, providing a reference for scientists and doctors that documented the anatomy of these cells.

Format: Articles

Subject: Publications, Reproduction

Elizabeth Blackburn, Carol Greider and Jack Szostak's Telomere and Telomerase Experiments (1982-1989)

Experiments conducted by Elizabeth Blackburn, Carol Greider, and Jack Szostak from 1982 to 1989 provided theories of how the ends of chromosomes, called telomeres, and the enzyme that repairs telomeres, called telomerase, worked. The experiments took place at the Sidney Farber Cancer Institute and at Harvard Medical School in Boston, Massachusetts, and at the University of California in Berkeley, California. For their research on telomeres and telomerase, Blackburn, Greider, and Szostak received the Nobel Prize in Physiology or Medicine in 2009.

Format: Articles

Subject: Experiments

George Wells Beadle (1903-1989)

George Wells Beadle studied corn, fruit flies, and funguses in the US during the twentieth century. These studies helped Beadle earn the 1958 Nobel Prize in Physiology or Medicine. Beadle shared the prize with Edward Tatum for their discovery that genes help regulate chemical processes in and between cells. This finding, initially termed the one gene-one enzyme hypothesis, helped scientists develop new techniques to study genes and DNA as molecules, not just as units of heredity between generations of organisms.

Format: Articles

Subject: People

Ina May Gaskin (1940– )

Ina May Gaskin is a certified professional midwife, or CPM, in the US during the late twentieth and early twenty-first centuries. She worked at the Farm Midwifery Center in Summertown, Tennessee, a center well known for its low rates of intervention, which contributed to low rates of maternal and fetal mortality. One technique Gaskin used when assisting women with delivery helped resolve a complication called shoulder dystocia, which is when a part of the infant’s body is delivered, but the rest of the body is stuck in the birth canal.

Format: Articles

Subject: People

Pope John Paul II (1920-2005)

Pope John Paul II's views on abortion and embryology have been very influential to the Roman Catholic Church. He strictly forbade abortion and other threats to what he regarded as early human life in his encyclical entitled "Evangelium Vitae," meaning the "Gospel of Life." His authority on moral and social issues was highly regarded during his lifetime.

Format: Articles

Subject: People, Religion, Reproduction

Regnier de Graaf (1641-1673)

Regnier de Graaf, a Dutch physician and anatomist, was born 30 July 1641 in Schoonhoven, the Netherlands. Though he published papers on both pancreatic and male reproductive anatomy, he is best known for his discovery of the mature ovarian follicles as well as his contributions to the general body of knowledge surrounding the female mammalian reproductive organs.

Format: Articles

Subject: People

The Role of the Notch signaling pathway in Somitogenesis

Among other functions, the Notch signaling pathway contributes to the development of somites in animals. It involves a cell signaling mechanism with a wide range of functions, including cellular differentiation, and the formation of the embryonic structures (embryogenesis). All multicellular animals use Notch signaling, which is involved in the development, maintenance, and regeneration of a range of tissues. The Notch signaling pathways spans two cells, and consists of receptor proteins, which cross one cell's membrane and interacts with proteins on adjacent cells, called ligands.

Format: Articles

Subject: Theories, Processes

The Baby Makers (2012)

In 2012, the production company Waddell Media Production released the documentary The Baby Makers. The four-part series, directed and produced by Edel O’Mahony, follows multiple couples in Northern Ireland struggling with infertility problems as they utilize different treatments such as in vitro fertilization, or IVF, egg donation, and egg freezing. IVF is a procedure in which a woman’s egg is fertilized by a sperm outside of her body. Once the sperm fertilizes the egg, a fertility doctor places the fertilized egg back into the woman’s uterus.

Format: Articles

Subject: Outreach