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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

Embryo Blotting Paper Models

Anatomical models have always been a mainstay of descriptive embryology. As the training of embryologists grew in the late 1800s, so too did the need for large-scale teaching models. Embryo wax models, such as those made by Adolf Ziegler and Gustav Born, were popular in the latter part of the nineteenth century and the early twentieth century as a way to visualize, in three dimensions, the fine detail of embryos without the aid of a microscope.

Format: Articles

Subject: Technologies

"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

Carl Richard Moore (1892-1955)

Carl Richard Moore was a professor and researcher at the University of Chicago in Chicago, Illinois who studied sex hormones in animals from 1916 until his death in 1955. Moore focused on the role of hormones on sex differentiation in offspring, the optimal conditions for sperm production, and the effects of vasectomy or testicular implants on male sex hormone production. Moore's experiments to create hermaphrodites in the laboratory contributed to the theory of a feedback loop between the pituitary and fetal gonadal hormones to control sex differentiation.

Format: Articles

Subject: People

José Pedro Balmaceda (1948- )

José Pedro Balmaceda was born 22 August 1948 in Santiago, Chile. His mother Juanita owned a women's boutique in the city and his father José was a successful owner of several timber mills. He grew up with five sisters who remained in Santiago all their lives. Balmaceda attended the college preparatory school San Ignatius where he met Sergio Stone, his future partner at the Center for Reproductive Health fertility clinic in the University of California Irvine Medical Center.

Format: Articles

Subject: People, Reproduction

Hermann Joseph Muller's Study of X-rays as a Mutagen, (1926-1927)

Hermann Joseph Muller conducted three experiments in 1926 and 1927 that demonstrated that exposure to x-rays, a form of high-energy radiation, can cause genetic mutations, changes to an organism's genome, particularly in egg and sperm cells. In his experiments, Muller exposed fruit flies (Drosophila) to x-rays, mated the flies, and observed the number of mutations in the offspring. In 1927, Muller described the results of his experiments in "Artificial Transmutation of the Gene" and "The Problem of Genic Modification".

Format: Articles

Subject: Experiments

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

The Meckel-Serres Conception of Recapitulation

Johann Friedrich Meckel and Antoine Etienne Reynaud Augustin Serres developed in the early 1800s the basic principles of what later became called the Meckel-Serres Law. Meckel and Serres both argued that fetal deformities result when development prematurely stops, and they argued that these arrests characterized lower life forms, through which higher order organisms progress during normal development. The concept that the embryos of higher order organisms progress through successive stages in which they resemble lower level forms is called recapitulation.

Format: Articles

Subject: Theories

“Sources of Human Psychological Differences: The Minnesota Study of Twins Reared Apart” (1990), by Thomas J. Bouchard Jr, David T. Lykken, Matthew McGue, Nancy L. Segal and Auke Tellegen

In 1990, Thomas J. Bouchard and his colleagues published the paper “Sources of Human Psychological Differences: The Minnesota Study of Twins Reared Apart” in Science Magazine. The paper described the results of a study initiated in 1979 on the development of twins raised in different environments. The scientists conducted their experiment at the University of Minnesota, in Minneapolis, Minnesota. The researchers physiologically and psychologically assessed monozygotic twins or triplets who were reared apart, comparing the similarity of those twins to twins who were reared together.

Format: Articles

Subject: Publications

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

Golden Rice

Golden Rice was engineered from normal rice by Ingo Potrykus and Peter Beyer in the 1990s to help improve human health. Golden Rice has an engineered multi-gene biochemical pathway in its genome. This pathway produces beta-carotene, a molecule that becomes vitamin A when metabolized by humans. Ingo Potrykus worked at the Swiss Federal Institute of Technology in Zurich, Switzerland, and Peter Beyer worked at University of Freiburg, in Freiburg, Germany. The US Rockefeller Foundation supported their collaboration.

Format: Articles

Subject: Organisms, Legal

Keith Henry Stockman Campbell (1954-2012)

Keith Henry Stockman Campbell studied embryo growth and cell differentiation during the twentieth and twenty-first centuries in the UK. In 1995, Campbell and his scientific team used cells grown and differentiated in a laboratory to clone sheep for the first time. They named these two sheep Megan and Morag. Campbell and his team also cloned a sheep from adult cells in 1996, which they named Dolly. Dolly was the first mammal cloned from specialized adult (somatic) cells with the technique of somatic cell nuclear transfer (SCNT).

Format: Articles

Subject: People

Columbia Gang

Format: Photographs

Subject: People

Columbia Gang

Format: Photographs

Subject: People

Induced Pluripotent Stem Cell Experiments by Kazutoshi Takahashi and Shinya Yamanaka in 2006 and 2007

In 2006, Kazutoshi Takahashi and Shinya Yamanaka reprogrammed mice fibroblast cells, which can produce only other fibroblast cells, to become pluripotent stem cells, which have the capacity to produce many different types of cells. Takahashi and Yamanaka also experimented with human cell cultures in 2007. Each worked at Kyoto University in Kyoto, Japan. They called the pluripotent stem cells that they produced induced pluripotent stem cells (iPSCs) because they had induced the adult cells, called differentiated cells, to become pluripotent stem cells through genetic manipulation.

Format: Articles

Subject: Experiments

Countdown to Life: The Extraordinary Making of You (2015), by the British Broadcasting Corporation and The Open University

In 2015, the British Broadcasting Corporation (BBC) partnered with The Open University to produce the three-part documentary series, Countdown to Life: The Extraordinary Making of You. Michael Mosley, a British television producer and journalist, hosts the documentary. Along with narrating animated scenes of a growing fetus in the womb, Mosley meets with individuals around the world who experienced mutations that can arise in the womb. Introduced over the course of the three episodes, several people share their personal stories of how their bodies did not develop correctly prior to birth.

Format: Articles

Subject: Publications

The National Society of Genetic Counselors (NSGC)

Audrey Heimler and colleagues founded the National Society of Genetic Counselors (NSGC) in 1979 in New Hyde Park in New York, New York. Her stated goals were to establish the field of genetic counseling within biomedicine and to coordinate counselors’ voices, so that physicians and others in the medical industry would not dictate the future of the field. Genetic counselors inform patients about the potential for inherited diseases passed on through family lineages and help to navigate the options available.

Format: Articles

Subject: Organizations

Charles Robert Cantor (1942- )

Charles Robert Cantor helped sequence the human genome, and he developed methods to non-invasively determine the genes in human fetuses. Cantor worked in the US during the twentieth and twenty-first centuries. His early research focused on oligonucleotides, small molecules of DNA or RNA. That research enabled the development of a technique that Cantor subsequently used to describe nucleotide sequences of DNA, a process called sequencing, in humans. Cantor was the principal scientist for the Human Genome Project, for which scientists sequenced the entirety of the human genome in 2003.

Format: Articles

Subject: People, Reproduction

Wilhelm His, Sr. (1831-1904)

Wilhelm His, Sr. was born on 9 July 1831 in Basel, Switzerland, to Katharina La Roche and Eduard His. He began his medical studies at Basel in 1849 and later transferred to the University of Bern during the winter semester of 1849-1850. A year later, His arrived at the University of Berlin, where he studied under Johannes Müller and Robert Remak. For his clinical training, His attended the University of Würzburg from 1852-1853.

Format: Articles

Subject: People

The Mechanistic Conception of Life (1912), by Jacques Loeb

Jacques Loeb published The Mechanistic Conception of Life in 1912. Loeb's goal for the book was to further disseminate his explanations of organic processes, such as embryonic development and organisms orientations to their environments, which relied on physics and chemistry. Loeb also wanted to provide an alternative explanatory framework to vitalism and what he called romantic evolutionism, then both widespread.

Format: Articles

Subject: Publications

Gamete Intra-Fallopian Transfer (GIFT)

Various techniques constitute assisted reproduction, one of which is gamete intra-fallopian transfer (GIFT). The first example of GIFT involved primates during the 1970s; however, the technology was unsuccessful until 1984 when an effective GIFT method was invented by Ricardo Asch at the University of Texas Health Sciences Center and the procedure resulted in the first human pregnancy. The GIFT technique was created in hopes of generating an artificial insemination process that mimicked the physiological sequences of normal conception.

Format: Articles

Subject: Technologies, Reproduction

Frank Rattray Lillie's Study of Freemartins (1914-1920)

Frank Rattray Lillie's research on freemartins from 1914 to 1920 in the US led to the theory that hormones partly caused for sex differentiation in mammals. Although sometimes applied to sheep, goats, and pigs, the term freemartin most often refers to a sterile cow that has external female genitalia and internal male gonads and was born with a normal male twin.

Format: Articles

Subject: Experiments

Walter Jakob Gehring (1939-2014)

Walter Jakob Gehring discovered the homeobox, a DNA segment found in a specific cluster of genes that determine the body plan of animals, plants, and fungi. Gehring identified the homeobox in 1983, with the help of colleagues while isolating the Antennapedia (Antp) gene in fruit flies (Drosophila) at the University of Basel in Basel, Switzerland. Hox genes, a family of genes that have the homeobox, determine the head-to-tail (anterior-posterior) body axis of both vertebrates and invertebrates.

Format: Articles

Subject: People