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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

"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

“Diethylstilbestrol in the Prevention and Treatment of Complications of Pregnancy” (1948), by Olive Watkins Smith

In 1948, Olive Watkins Smith published 'Diethylstilbestrol in the Prevention and Treatment of Complications of Pregnancy' in the American Journal of Obstetrics and Gynecology. In 632 women treated with diethylstilbestrol, Smith demonstrated that the drug stimulated the production of progesterone, a hormone that regulates the uterine condition during pregnancy.

Format: Articles

Subject: Publications

Impact of Air Pollution on Reproductive Health” (1999), by Radim Srám

In 1999, researcher Radim Srám, sometimes spelled Radim Šrám, published his article “Impact of Air Pollution on Reproductive Health” in the journal Environmental Health Perspectives. In the article, Srám analyzes the effects of exposure to air pollution, which can include harmful chemicals, on fetal growth and development. Srám discusses how industrialized countries such as the US and China have led to an increase in the global amount of respirable air pollutants.

Format: Articles

Subject: Publications

Petr Alekseevich Kropotkin (1842-1921)

Petr Kropotkin proposed the theory of Pleistocene ice age, alternative theories of evolution based on embryology, and he advocated anarchist and communist social doctrines in Europe during the nineteenth and twentieth centuries. He traveled in eastern Siberia and Manchuria from 1863 until 1867, and his subsequent publications about that area's geography became authoritative until the middle of the twentieth century.

Format: Articles

Subject: People

Leuprorelin as a Treatment for Endometriosis

Leuprolide acetate, or leuprorelin, is a manufactured drug that has been prescribed as a treatment for endometriosis, a medical condition in which body tissue that typically lines the uterus grows outside of the uterus, since 1989. Leuprorelin is a modified version of a gonadotropin-releasing hormone, a type of hormone that helps regulate the female menstrual cycle. The drug inhibits the production of estrogen, a female sex hormone that enables endometrial gland growth.

Format: Articles

Subject: Processes

Beal v. Doe (1977)

In the case of Beal v. Doe, tried in 1977, the US Supreme Court ruled that states could constitutionally restrict money from Medicaid from funding elective abortions. After the 1973 case Roe v. Wade, in which the US Supreme Court had ruled women have the rights to terminate pregnancies within the first trimester, the state of Pennsylvania passed legislation that restricted the use of Medicaid funds for abortion procedures. In 1977, several Medicaid eligible women who were unable to receive coverage for a non-therapeutic abortion brought a case against Frank S.

Format: Articles

Subject: Legal

American Eugenics Society (1926-1972)

The American Eugenics Society (AES) was established in the US by
Madison Grant, Harry H. Laughlin, Henry Crampton, Irving Fisher, and
Henry F. Osborn in 1926 to promote eugenics education programs for
the US public. The AES described eugenics as the study of improving
the genetic composition of humans through controlled reproduction of
different races and classes of people. The AES aided smaller eugenic
efforts such as the Galton Society in New York, New York, and the

Format: Articles

Subject: Organizations

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

"On the Origin of Mitosing Cells" (1967), by Lynn Sagan

On the Origin of Mitosing Cells by Lynn Sagan appeared in the March 1967 edition of the Journal of Theoretical Biology. At the time the article was published, Lynn Sagan had divorced astronomer Carl Sagan, but kept his last name. Later, she remarried and changed her name to Lynn Margulis, and will be referred to as such throughout this article. In her 1967 article, Margulis develops a theory for the origin of complex cells that have enclosed nuclei, called eukaryotic cells.

Format: Articles

Subject: Publications, Theories

"Viable Offspring Derived from Fetal and Adult Mammalian Cells" (1997), by Ian Wilmut et al.

In the 1990s, Ian Wilmut, Jim McWhir, and Keith Campbell performed experiments while working at the Roslin Institute in Roslin, Scotland. Wilmut, McWhir, and Campbell collaborated with Angelica Schnieke and Alex J. Kind at PPL Therapeutics in Roslin, a company researching cloning and genetic manipulation for livestock. Their experiments resulted in several sheep being born in July 1996, one of which was a sheep named Dolly born 5 July 1996.

Format: Articles

Subject: Experiments

Roy Chapman Andrews (1884-1960)

Roy Chapman Andrews traveled the world studying fossils, from mammals to dinosaurs, during the first half of the twentieth century. Andrews worked and collected fossil specimens for the American Museum of Natural History (AMNH) in New York City, New York. Throughout his career, Andrews collected bones of many animal species, including a previously unknown species of a horned, herbivorous dinosaur, later named Proceratops andrewsi in his honor. Andrews published widely read narratives about his travels and field experiences, such as On the Trail of Ancient Man and Across Mongolian Plains.

Format: Articles

Subject: People

United States v. Dennett (1930)

In the 1930 US federal court case United States v. Dennett, Mary Coffin Ware Dennett was cleared of all charges of violating the anti-obscenity Comstock Act, a charge she had incurred by distributing her sex education pamphlet called The Sex Side of Life: An Explanation for Young People. The United States Postal Service charged Dennett under the Comstock Act, which prohibited the distribution of sex-related materials through the mail.

Format: Articles

Subject: Legal

A Series of YouTube Videos Detailing the “CRISPR Babies” Experiment (2018), by He Jiankui

In 2018, He Jiankui uploaded a series of videos to a YouTube channel titled “The He Lab” that detailed one of the first instances of a successful human birth after genome editing had been performed on an embryo using CRISPR-cas9. CRISPR-cas9 is a genome editing tool derived from bacteria that can be used to cut out and replace specific sequences of DNA. He genetically modified embryos at his lab in Shenzhen, China, to make them immune to contracting HIV through indirect perinatal transmission from their father, who was infected with the virus.

Format: Articles

Subject: Publications, Experiments, Ethics

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

Circulatory Changes at Birth

When placental mammals are born their circulatory systems undergo radical changes as the newborns are prepared for independent life. The lungs are engaged, becoming the primary source of fresh oxygen, replacing the placental barrier as a means for blood-gas exchange.

Format: Articles

Subject: Processes

Leonardo da Vinci's Embryological Annotations

Among his myriad scientific and artistic contributions, Leonardo da Vinci's work in embryology was groundbreaking. He observed and diagramed the previously undemonstrated position of the fetus in the womb with detailed accompanying annotations of his observations. Leonardo was highly paranoid of plagiarism and wrote all of his notes in mirror-like handwriting laden with his own codes, making his writing difficult to discern and delaying its impact.

Format: Articles

Subject: Publications

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

"Programmed Cell Death-II. Endocrine Potentiation of the Breakdown of the Intersegmental Muscles of Silkmoths" (1964), by Richard A. Lockshin and Carroll M. Williams

Richard A. Lockshin's 1963 PhD dissertation on cell death in insect metamorphosis was conducted under the supervision of Harvard insect physiologist Carroll M. Williams. Lockshin and Williams used this doctoral research as the basis for five articles, with the main title "Programmed Cell Death," that were published between 1964 and 1965 in the Journal of Insect Physiology. These articles examine the cytological processes, neuronal and endocrinal controls, and the influence of drugs on the mechanism of cell death observed in pupal muscle structures of the American silkmoth.

Format: Articles

Subject: Experiments, Publications

Gastrulation in Xenopus

The process of gastrulation allows for the formation of the germ layers in metazoan embryos, and is generally achieved through a series of complex and coordinated cellular movements. The process of gastrulation can be either diploblastic or triploblastic. In diploblastic organisms like cnidaria or ctenophora, only the endoderm and the ectoderm form; in triploblastic organisms (most other complex metazoans), triploblastic gastrulation produces all three germ layers.

Format: Articles

Subject: Processes

Paul Kammerer's Experiments on Salamanders (1903-1912)

In the early twentieth century, Paul Kammerer conducted a series of experiments to demonstrate that organisms could transmit characteristics acquired in their lifetimes to their offspring. In his 1809 publication, zoologist Jean-Baptiste Lamarck had hypothesized that living beings can inherit features their parents or ancestors acquired throughout life. By breeding salamanders, as well as frogs and other organisms, Kammerer tested Lamarck's hypothesis in an attempt to provide evidence for Lamarck's theory of the inheritance of acquired characteristics.

Format: Articles

Subject: Experiments

“Misericordia et Misera” Section 12 (2016) by Pope Francis of the Catholic Church

Misericordia et Misera (Mercy with Misery) was a letter written by Pope Francis and published in Rome, Italy, on 20 November 2016. Through the letter, Pope Francis gives priests the ability to grant forgiveness for abortion. Before Pope Francis’s letter, priests had some ability to grant forgiveness for the Catholic sin of abortion, but bishops had to grant that ability to the priests individually. Prior to the letter, the official rules of the Catholic Church did not state that priests could forgive abortion-related sins.

Format: Articles

Subject: Publications, Religion

Wilhelm Friedrich Phillip Pfeffer (1845-1920)

Wilhelm Friedrich Phillip Pfeffer studied plants in Germany during the late nineteenth and early twentieth centuries. He started his career as an apothecary, but Pfeffer also studied plant physiology, including how plants move and react to changes in light, temperature, and osmotic pressure. He created the Pfeffer Zelle apparatus, also known as the Pfeffer Cell, to study osmosis in plants. PfefferÕs experiments led to new theories about the structure and development of plants.

Format: Articles

Subject: People

“Women’s Right to Know” Informed Consent Informational Materials

As of 2021, twenty-eight US states have informed consent laws for abortion, which is a medical procedure to terminate pregnancy, often called Women’s Right to Know laws. Those laws often require the state government to develop informational materials that healthcare providers must give to women before an abortion. Informational materials generally include information about the process of fetal development, accompanied by illustrations or pictures, risks and effects of abortion, and alternatives to abortion.

Format: Articles

Subject: Legal