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Intraspecies Chimeras Produced in Laboratory Settings (1960-1975)

When cells-but not DNA-from two or more genetically distinct individuals combine to form a new individual, the result is called a chimera. Though chimeras occasionally occur in nature, scientists have produced chimeras in a laboratory setting since the 1960s. During the creation of a chimera, the DNA molecules do not exchange genetic material (recombine), unlike in sexual reproduction or in hybrid organisms, which result from genetic material exchanged between two different species. A chimera instead contains discrete cell populations with two unique sets of parental genes.

Format: Articles

Subject: Organisms, Processes

Seed Banking 1979-1994

In the early twentieth century, scientists and agriculturalists collected plants in greenhouses, botanical gardens, and fields. Seed collection efforts in the twentieth century coincided with the professionalization of plant breeding. When scientists became concerned over the loss of plant genetic diversity due to the expansion of a few agricultural crops around mid-century, countries and organizations created seed banks for long-term seed storage.

Format: Articles

Subject: Organizations

Biological Clocks and the Formation of Human Tooth Enamel

Tooth enamel contains relics of its formation process, in the form of microstructures, which indicate the incremental way in which it forms. These microstructures, called cross-striations and striae of Retzius, develop as enamel-forming cells called ameloblasts, whcih cyclically deposit enamel on developing teeth in accordance with two different biological clocks. Cross-striations result from a twenty-four hour cycle, called a Circadian rhythm, in the enamel deposition process, while striae of Retzius have a longer periodicity.

Format: Articles

Subject: Processes

Induced Pluripotent Stem Cells

Induced Pluripotent Stem Cells (iPSCs) are cells derived from non-pluripotent cells, such as adult somatic cells, that are genetically manipulated so as to return to an undifferentiated, pluripotent state. Research on iPSCs, initiated by Shinya Yamanaka in 2006 and extended by James Thompson in 2007, has so far revealed the same properties as embryonic stem cells (ESCs), making their discovery potentially very beneficial for scientists and ethicists alike.

Format: Articles

Subject: Technologies

"Mechanistic Science and Metaphysical Romance" (1915), by Jacques Loeb

Jacques Loeb published "Mechanistic Science and Metaphysical Romance" in 1915. His goal for the article was to outline his conception of mechanistic science and its relation to other methods of inquiry. Loeb argued that mechanistic science was the foundation of knowledge and humanity's progress depended on it. Loeb's argument altered the account of science he offered in The Mechanistic Conception of Life insofar as scientists no longer aimed merely to control nature, but also to understand nature s underlying elements and their mechanical relations.

Format: Articles

Subject: Publications

Stanley Alan Plotkin's Development of a Rubella Vaccine (1969)

In the US during the late 1960s, Stanley Alan Plotkin, John D. Farquhar, Michael Katz, and Fritz Buser isolated a strain of the infectious disease rubella and developed a rubella vaccine with a weakened, or attenuated, version of the virus strain. Rubella, also called German measles, is a highly contagious disease caused by the rubella virus that generally causes mild rashes and fever. However, in pregnant women, rubella infections can lead to developmental defects in their fetuses.

Format: Articles

Subject: Experiments

Simon Edward Fisher (1970-)

Simon Edward Fisher studied the genes that control speech and language in England and the Netherlands in the late twentieth and early twenty-first centuries. In 2001, Fisher co-discovered the FOXP2 gene with Cecilia Lai, a gene related to language acquisition in humans and vocalization in other mammals. When damaged, the human version of the gene leads to language disorders that disrupt language and speech skills. Fisher's discovery validated the hypothesis that genes influence language, resulting in further investigations of language disorders and their heritability.

Format: Articles

Subject: People

The Inheritance of Acquired Characteristics (1924), by Paul Kammerer

The Inheritance of Acquired Characteristics is a book published in 1924, written by Paul Kammerer, who studied developmental biology in Vienna, Austria, in the early twentieth century. The Inheritance of Acquired Characteristics summarizes Kammerer's experiments, and explains their significance. In his book, Kammerer aims to explain how offspring inherit traits from their parents. Some scholars criticized Kammerer's reports and interpretations, arguing that they were inaccurate and misleading, while others supported Kammerer's work.

Format: Articles

Subject: Publications, Theories

"CRISPR /Cas9-mediated Gene Editing in Human Tripronuclear Zygotes" (2015), by Junjiu Huang et al.

In 2015, Junjiu Huang and his colleagues reported their attempt to enable CRISPR/cas 9-mediated gene editing in nonviable human zygotes for the first time at Sun Yat-Sen University in Guangzhou, China. Their article, CRISPR /Cas9-mediated Gene Editing in Human Tripronuclear Zygotes, was published in Protein and Cell. Nonviable zygotes are sperm-fertilized eggs that cannot develop into a fetus. Researchers previously developed the CRISPR/cas 9 gene editing tool, which is a system that originated from bacteria as a defense mechanism against viruses.

Format: Articles

Subject: Publications, Experiments

Margaret Ann Bulkley (James Barry) (1789−1865)

Margaret Ann Bulkley, under the male pseudonym James Barry, was one of the first female obstetricians in early nineteenth century British Empire. She was the first person to perform a cesarean section in South Africa. Cesarean section is a procedure in which a doctor cuts into the uterus of a pregnant woman to retrieve the fetus during complicated births. Bulkley hid her gender and lived life as the male Barry to practice medicine, an opportunity not allowed to women at the time.

Format: Articles

Subject: People

Ricardo Hector Asch (1947- )

Ricardo Hector Asch was born 26 October 1947 in Buenos Aires, Argentina, to a lawyer and French professor, Bertha, and a doctor and professor of surgery, Miguel. Asch's middle-class family lived among the largest Jewish community in Latin America, where a majority of males were professionals. After his graduation from National College No. 3 Mariano Moreno in Buenos Aires, Asch worked as a teaching assistant in human reproduction and embryology at the University of Buenos Aires School of Medicine where he received his medical degree in 1971.

Format: Articles

Subject: Ethics, People

William Smellie (1697–1763)

William Smellie helped to incorporate scientific medicine into the process of childbirth in eighteenth century Britain. As a male physician practicing in childbirth and female reproductive health (man-midwife), Smellie developed and taught procedures to treat breech fetuses, which occur when a fetus fails to rotate its head towards the birth canal during delivery. Throughout his career, Smellie compiled a wealth of information about female anatomy in his writings. He modified medical technology such as the obstetrical forceps, an instrument used to maneuver the fetus during childbirth.

Format: Articles

Subject: People, Reproduction

Park v. Chessin (1977)

The New York Appellate Court ruled on 11 December 1977 in favor of Steven and Hetty Park and against Herbert Chessin for the wrongful life of the Parks' child. In a wrongful life case, a disabled or sometimes deceased child brings suit against a physician for failing to inform its parents of possible genetic defects, thereby causing harm to the child when born. Park v. Chessin was the first case to rule that medical personnel could be legally responsible for wrongful life. Further cases such as the 1979 case Berman v. Allan and the 1982 case Turpin v.

Format: Articles

Subject: Legal, Reproduction

Turpin v. Sortini (1982)

The Supreme Court of California reversed the Superior Court of Fresno County's decision to dismiss the Turpins' claims in the case Turpin v. Sortini on 3 May 1982. The case was based upon a wrongful life claim, in which a disabled child sues physicians for neglecting to inform its parents of potential genetic defects, resulting in harm to the child when it is born. The Turpin case determined tha a physician could be liable for failing to inform parents of potential birth defects in the fetus.

Format: Articles

Subject: Legal, Reproduction

Victor Ambros (1953-)

Victor Ambros is a professor of molecular medicine at the University of Massachusetts Medical School, and he discovered the first microRNA (miRNA) in 1993. Ambros researched the genetic control of developmental timing in the nematode worm Caenorhabditis elegans and he helped describe gene function and regulation during the worm’s development and embryogenesis. His discovery of miRNA marked the beginning of research into a form of genetic regulation found throughout diverse life forms from plants to humans. Ambros is a central figure in the miRNA and C.

Format: Articles

Subject: People

The Infant Incubator in Europe (1860-1890)

In the nineteenth century, obstetricians in Europe began to construct devices to incubate infants in increasingly controlled environments. The infant incubator is a medical device that maintains stable conditions and a germ free environment for premature infants born before the thirty-seventh week of pregnancy. Records show that physicians had used infant incubators since 1835. However, Jean-Louis-Paul Denuce, a physician who worked in Bordeaux, France, first published about incubator technology in 1857.

Format: Articles

Subject: Technologies, Reproduction

"Induction and Patterning of the Primitive Streak, an Organizing Center of Gastrulation in the Amniote" (2004), by Takashi Mikawa, Alisa M. Poh, Kristine A. Kelly, Yasuo Ishii, and David E. Reese

"Induction and Patterning of the Primitive Streak, an Organizing Center of Gastrulation in the Amniote," (hereafter referred to as "Induction") examines the mechanisms underlying early amniote gastrulation and the formation of the primitive streak and midline axis. The review, authored by Takashi Mikawa and colleagues at Cornell University Medical College, was published in Developmental Dynamics in 2004.

Format: Articles

Subject: Publications

Richard Doll (1912–2005)

Richard Doll was an epidemiologist and public figure in the twentieth and early twenty-first centuries. Working primarily at the University of Oxford, in Oxford, England, Doll established a definitive correlation between cigarette smoking and lung cancer. Furthermore, Doll’s work helped legitimize epidemiology as a scientific discipline. Doll’s research also helped establish modern guidelines for oncological studies, as well as for contemporary and future research on the effect of smoking on pregnancy and fetal development.

Format: Articles

Subject: People

William Thornton Mustard (1914-1987)

William Thornton Mustard was a surgeon in Canada during the twentieth century who developed surgical techniques to treat children who had congenital heart defects. Mustard has two surgeries named after him, both of which he helped to develop. The first of these surgeries replaces damaged or paralyzed muscles in individuals who have polio, a virus that can cause paralysis. The other technique corrects a condition called the transposition of the great arteries (TGA) that is noticed at birth.

Format: Articles

Subject: People, Disorders, Disorders

Etienne Geoffroy Saint-Hilaire (1772-1844)

Etienne Geoffroy Saint-Hilaire, commonly known as Geoffroy, studied animals, their anatomy and their embryos, and teratogens at the National Museum of Natural History in Paris, France in the eighteenth and nineteenth centuries. Geoffroy also helped develop several specialized fields in the life sciences, including experimental embryology. In his efforts to experimentally demonstrate the theory of recapitulation, Geoffroy developed techniques to intervene in the growth of embryos to see whether they would develop into different kinds of organisms.

Format: Articles

Subject: People

Dandy-Walker Syndrome

Dandy-Walker Syndrome is a congenital brain defect in humans characterized by malformations to the cerebellum, the part of the brain that controls movement, and to the ventricles, the fluid-filled cavities that surround the cerebellum. The syndrome is named for physicians Walter Dandy and Arthur Walker who described associated signs and symptoms of the syndrome in the 1900s. The malformations often develop during embryonic stages.

Format: Articles

Subject: Disorders

Uniform Anatomical Gift Act (1968)

The Uniform Anatomical Gift Act (UAGA or the Act) was passed in the US in 1968 and has since been revised in 1987 and in 2006. The Act sets a regulatory framework for the donation of organs, tissues, and other human body parts in the US. The UAGA helps regulate body donations to science, medicine, and education. The Act has been consulted in discussions about abortion , fetal tissue transplants , and Body Worlds , an anatomy exhibition.

Format: Articles

Subject: Legal, Outreach, Reproduction

Clinica Para Madres (1934-1950)

The Clinica Para Madres (Mother’s Clinic) opened in Tucson, Arizona, in December of 1934 as the first birth control clinic in Arizona. After moving to Tucson, birth control activist Margaret Sanger, along with a group of local philanthropic women, founded the clinic to provide Arizona women with contraception. During the early 1900s in the US, contraception was illegal under the federal Comstock Act. Additionally, many viewed contraception and sex as obscene and not to be discussed in public or outside of marriage.

Format: Articles

Subject: Organizations, Reproduction, Outreach

Bernard Nathanson (1926-2011)

Bernard Nathanson was an obstetrician and gynecologist in New York City, New York, who argued for, and later against, women's rights to abortion. Between 1970 and 1979, Nathanson oversaw at least 75,000 abortions, 5,000 of which he performed himself, earning him the nickname of abortion king. However, his views regarding abortion shifted in 1973, after he watched an abortion using ultrasound imaging technology. Afterwards, Nathanson began to oppose women's rights to abortion, and he published the anti-abortion book Aborting America and produced the film Silent Scream.

Format: Articles

Subject: People, Reproduction