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Roy John Britten (1919-2012)

Roy John Britten studied DNA sequences in the US in the second
half of the twentieth century, and he helped discover repetitive
elements in DNA sequences. Additionally, Britten helped propose
models and concepts of gene regulatory networks. Britten studied the
organization of repetitive elements and, analyzing data from the
Human Genome Project, he found that the repetitive elements in DNA
segments do not code for proteins, enzymes, or cellular parts.
Britten hypothesized that repetitive elements helped cause cells to

Format: Articles

Subject: People

Hamlin Fistula Ethiopia (1974- )

Hamlin Fistula Ethiopia is a nonprofit organization that began in 1974 as a joint endeavor by Reginald and Catherine Hamlin and the Addis Ababa Fistula Hospital in Addis Ababa, Ethiopia. Hamlin Fistula Ethiopia promotes reproductive health in Ethiopia by raising awareness and implementing treatment and preventive services for women affected by obstetric fistulas. It also aims to restore the lives of women afflicted with obstetric fistulas in Ethiopia and eventually to eradicate the condition.

Format: Articles

Subject: Organizations, Reproduction, Outreach

Studies of Thalidomide's Effects on Rodent Embryos from 1962-2008

Thalidomide is a sedative drug introduced to European markets on 1 October 1957 after extensive testing on rodent embryos to ensure its safety. Early laboratory tests in rodent populations showed that pregnant rodents could safely use it, so doctors prescribed Thalidomide to treat morning sickness in pregnant women. However, in humans Thalidomide interfered with embryonic and fetal development in ways not observed in rodent tests.

Format: Articles

Subject: Organisms, Reproduction, Disorders

Ian Hector Frazer (1953– )

Ian Hector Frazer studied the human immune system and vaccines in Brisbane, Australia, and helped invent and patent the scientific process and technology behind what later became the human papillomavirus, or HPV, vaccinations. According to the Centers for Disease Control and Prevention of the US, or CDC, HPV is the most common sexually transmitted infection, and can lead to genital warts, as well as cervical, head, mouth, and neck cancers.

Format: Articles

Subject: People

Roger Sperry’s Split Brain Experiments (1959–1968)

In the 1950s and 1960s, Roger Sperry performed experiments on cats, monkeys, and humans to study functional differences between the two hemispheres of the brain in the United States. To do so he studied the corpus callosum, which is a large bundle of neurons that connects the two hemispheres of the brain. Sperry severed the corpus callosum in cats and monkeys to study the function of each side of the brain. He found that if hemispheres were not connected, they functioned independently of one another, which he called a split-brain.

Format: Articles

Subject: Experiments

Agent Orange as a Cause of Spina Bifida

Spina bifida is a birth defect that affects the spines of developing fetuses and infants, and research in the 20th century indicated that chemicals in the herbicide Agent Orange likely lead to the birth defect. People with spina bifida can have nerve damage, paralysis, and mental disabilities. During the Vietnam War in the 1960s, the US military employed Agent Orange and other herbicides to destroy enemy crops and forest cover until 1970.

Format: Articles

Subject: Disorders

Alec John Jeffreys (1950–)

Alec John Jeffreys created a process called DNA fingerprinting in the UK during the twentieth century. For DNA fingerprinting, technicians identify a person as the source of a biological sample by comparing the genetic information contained in the person's DNA to the DNA contained in the sample. Jeffreys developed the technique in the 1980s while at the University of Leicester in Leicester, UK. Jeffreys's technique had immediate applications. In forensic science, DNA fingerprinting enabled police to identify suspects of crimes based on their genetic identities.

Format: Articles

Subject: People

Max Ludwig Henning Delbruck (1906–1981)

Max Ludwig Henning Delbrick applied his knowledge of theoretical physics to biological systems such as bacterial viruses called bacteriophages, or phages, and gene replication during the twentieth century in Germany and the US. Delbrück demonstrated that bacteria undergo random genetic mutations to resist phage infections. Those findings linked bacterial genetics to the genetics of higher organisms. In the mid-twentieth century, Delbrück helped start the Phage Group and Phage Course in the US, which further organized phage research.

Format: Articles

Subject: People

The Guthrie Test for Early Diagnosis of Phenylketonuria

The Guthrie test, also called the PKU test, is a diagnostic tool to test infants for phenylketonuria a few days after birth. To administer the Guthrie test, doctors use Guthrie cards to collect capillary blood from an infant’s heel, and the cards are saved for later testing. Robert Guthrie invented the test in 1962 in Buffalo, New York. Phenylketonuria (PKU) is a congenital birth abnormality in which toxic levels of the amino acid phenylalanine build up in the blood, a process that affects the brains in untreated infants.

Format: Articles

Subject: Technologies

In the Womb (2005), by Toby Mcdonald and National Geographic Channel

Written, produced, and directed by Toby Mcdonald, the 2005 National Geographic Channel film In the Womb uses the most recent technology to provide an intricate glimpse into the prenatal world. The technologies used, which include advanced photography, computer graphics, and 4-D ultrasound imaging, help to realistically illustrate the process of development and to answer questions about the rarely seen development of a human being.

Format: Articles

Subject: Outreach, Reproduction

"A Genomic Regulatory Network for Development" (2002), by Eric H. Davidson, et al.

In 2002 Eric Davidson and his research team published 'A Genomic Regulatory Network for Development' in Science. The authors present the first experimental verification and systemic description of a gene regulatory network. This publication represents the culmination of greater than thirty years of work on gene regulation that began in 1969 with 'A Gene Regulatory Network for Development: A Theory' by Roy Britten and Davidson. The modeling of a large number of interactions in a gene network had not been achieved before.

Format: Articles

Subject: Publications

Essay: Review of Icons of Life: A Cultural History of Human Embryos

To Lynn M. Morgan, the Mary E. Woolley Professor of Anthropology at Mt. Holyoke College, nothing says life more than a dead embryo. In her easily readable book, Icons of Life: A Cultural History of Human Embryos, Morgan brings together cultural phenomena, ethics, and embryology to show that even dead embryos and fetuses have their own stories to tell. As an anthropologist, Morgan is interested in many things, including the science of embryology and its history. But she also wants to know how culture influences our views on embryos and the material practices that accompany their study.

Format: Essays and Theses

Subject: Publications

"Hybrids and Chimeras: A Consultation on the Ethical and Social Implications of Creating Human/Animal Embryos in Research" (2007), by the HFEA

To educate its citizens about research into chimeras made from human and non-human animal cells, the United Kingdom's Human Fertilisation Embryology Authority published the consultation piece Hybrids and Chimeras: A Consultation on the Ethical and Social Implications of Creating Human/Animal Embryos in Research, in 2007.

Format: Articles

Subject: Publications

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

Meselson, Stahl, and the Replication of DNA: A History of "The Most Beautiful Experiment in Biology" (2001), by Frederic Lawrence Holmes

In 2001, Yale University Press published Frederic Lawrence Holmes' book, Meselson, Stahl, and the Replication of DNA: A History of "The Most Beautiful Experiment in Biology" (Replication of DNA), which chronicles the 1950s debate about how DNA replicates. That experiment verified that DNA replicates semi-conservatively as originally proposed by Watson and Crick. Rather than focusing solely on experiments and findings, Holmes's book presents the investigative processes of scientists studying DNA replication.

Format: Articles

Subject: Publications

“Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Desoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III” (1944) by Oswald Avery, Colin MacLeod and Maclyn McCarty

In 1944, Oswald Avery, Colin MacLeod, and Maclyn McCarty published an article in which they concluded that genes, or molecules that dictate how organisms develop, are made of deoxyribonucleic acid, or DNA. The article is titled “Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Desoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III,” hereafter “Transformation.” The authors isolated, purified, and characterized genes within bacteria and found evidence that those genes were made of DNA and not protein.

Format: Articles

Subject: Publications

The Development of Silicone Breast Implants for Use in Breast Augmentation Surgeries in the United States

In the 1960s, two plastic surgeons from the United States, Thomas Dillon Cronin and Frank Judson Gerow, collaborated with the Dow Corning Corporation, which specialized in silicone products, to create the first silicone breast implant. Surgeons used the implant, named the Cronin-Gerow implant, to improve the look of a woman’s breasts, by correcting for asymmetry, augmenting the size, or creating a more uplifted profile.

Format: Articles

Subject: Technologies, Processes

Breast Augmentation Techniques

Breast augmentation involves the use of implants or fat tissue to increase patient breast size. As of 2019, breast augmentation is the most popular surgical cosmetic procedure in the United States, with annual patient numbers increasing by 41 percent since the year 2000. Since the first documented breast augmentation by surgeon Vincenz Czerny in 1895, and later the invention of the silicone breast implant in 1963, surgeons have developed the procedure into its own specialized field of surgery, creating various operating techniques for different results.

Format: Articles

Subject: Technologies, Processes, Reproduction, Ethics

Menstrual Tampon

Menstrual tampons are feminine hygiene devices, usually made of absorbent cotton, that are temporarily inserted into the vagina for absorbing a woman’s blood during menstruation. In 1931, Earl Haas invented the menstrual tampon most commonly used in the twenty-first century. Later, Gertrude Tendrich produced the first commercial tampon brand, Tampax, using Haas’s patented design. Tendrich and Haas’s tampon was made of tightly compacted absorbent cotton, shaped like a bullet, and had a string attached at the base that allowed for easy removal from the woman’s body.

Format: Articles

Subject: Technologies

Horatio Robinson Storer (1830–1922)

Horatio Robinson Storer was a surgeon and anti-abortion activist in the 1800s who worked in the field of women’s reproductive health and led the Physicians’ Crusade Against Abortion in the US. Historians credit Storer as being one of the first physicians to distinguish gynecology, the study of diseases affecting women and their reproductive health, as a separate subject from obstetrics, the study of pregnancy and childbirth.

Format: Articles

Subject: People, Reproduction, Religion

“Prenatal Stress, Glucocorticoids and the Programming of the Brain” (2001), by Leonie Welberg and Jonathan Seckl

In 2001, researchers Leonie Welberg and Jonathan Seckl published the literature review “Prenatal Stress, Glucocorticoids, and the Programming of the Brain,” in which they report on the effects of prenatal stress on the development of the fetal brain. The fetus experiences prenatal stress while in the womb, or in utero. In discussing the effects of prenatal stress, the authors describe prenatal programming, which is when early environmental experiences permanently alter biological structure and function throughout life.

Format: Articles

Subject: Publications, Theories

Peter Mazur (1928–2015)

Peter Mazur was a researcher in the US who developed new ways of preserving biological material by freezing it, a process called cryopreservation. If done correctly, cryopreservation enables scientists to store or study biological material for an extended period of time. If done incorrectly, cryopreservation can easily harm or destroy biological material. Mazur worked to find the best ways to cryopreserve different cells, embryos, and organs in order to minimize the damage caused by freezing.

Format: Articles

Subject: People

Essay: The Cuvier-Geoffroy Debate

In 1830, a dispute erupted in the halls of lÕAcad mie des Sciences in Paris between the two most prominent anatomists of the nineteenth century. Georges Cuvier and tienne Geoffroy Saint-Hilaire, once friends and colleagues at the Paris Museum, became arch rivals after this historical episode. Like many important disputes in the history of science, this debate echoes several points of contrasts between the two thinkers.

Format: Essays and Theses

Subject: Theories

My Father, My Son (1986), by Elmo Zumwalt, Jr., Elmo Zumwalt III, and John Pekkanen

My Father, My Son is a dual autobiography by father and son Elmo Russell Zumwalt Jr. and Elmo Russell Zumwalt III published by Macmillan Publishing Company in 1986, detailing their experiences during the Vietnam War and particularly with Agent Orange, an herbicide used for defoliation and crop destruction during the war. As a commander in the Navy, Zumwalt Jr. ordered the use of Agent Orange in South Vietnam, where Zumwalt III was stationed.

Format: Articles

Subject: Publications

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