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No-scalpel Vasectomy

No-scalpel vasectomy, or NSV or keyhole vasectomy, is a surgical method of sterilization that involves puncturing the skin of the scrotum to access the vas deferens, a tube that carries spermatozoa, or sperm, from the testes to the penis. The surgeon performing the procedure blocks the flow of sperm through the vas deferens, sterilizing the patient. NSV is a less invasive procedure, as it does not use a scalpel to make a deep cut on sensitive scrotal tissue.

Format: Articles

Subject: Technologies, People, Organizations, Places, Reproduction

HeLa Cell Line

The HeLa cell line was the first immortal human cell line that George Otto Gey, Margaret Gey, and Mary Kucibek first isolated from Henrietta Lacks and developed at The Johns Hopkins Hospital in Baltimore, Maryland, in 1951. An immortal human cell line is a cluster of cells that continuously multiply on their own outside of the human from which they originated. Scientists use immortal human cell lines in their research to investigate how cells function in humans.

Format: Articles

Subject: Technologies, Experiments, People, Ethics

Ross Granville Harrison (1870-1959)

A pioneer in experimental embryology, Ross Granville Harrison made numerous discoveries that advanced biology. One of the most significant was his adaptation of the hanging drop method from bacteriology to carry out the first tissue culture. This method allowed for further studies in embryology as well as experimental improvements in oncology, virology, genetics, and a number of other fields.

Format: Articles

Subject: People

August Antonius Rauber (1841-1917)

August Antonius Rauber was an embryologist and anatomist who examined gastrulation in avian embryos. He examined the formation of the blastopore, epiblast, and primitive streak during chick development. Subsequent researchers have further studied Rauber's findings, which has led to new discoveries in embryology and developmental biology.

Format: Articles

Subject: People

Wilhelm Roux (1850-1924)

Wilhelm Roux was a nineteenth-century experimental embryologist who was best known for pioneering Entwicklungsmechanik, or developmental mechanics. Roux was born in Jena, Germany, on 9 June 1850, the only son of Clotilde Baumbach and a university fencing master, F. A. Wilhelm Ludwig Roux. Roux described himself as an aloof child, but when he was fourteen he cultivated a passion for science that was encouraged by the director at Oberrealschule in Meiningen.

Format: Articles

Subject: People

Emil von Behring (1854–1917)

Emil von Behring researched treatments for the common childhood disease diphtheria in Germany in the 1890s and early 1900s. Diphtheria is a lethal disease that infected approximately 40,000 people in Germany between 1886 and 1888 with a general mortality rate of twenty-five percent. Behring investigated treatment of diphtheria using serum therapy, which is an alternative to vaccination that uses protective agents from other people’s blood to defend a patient against disease. Behring termed those protective agents antitoxins.

Format: Articles

Subject: People, Theories

Beatrice Mintz (1922–2022)

Beatrice Mintz is a brilliant researcher who has developed techniques essential for many aspects of research on mouse development. She produced the first successful mouse chimeras and meticulously characterized their traits. She has worked with various cancers and produced viable mice from the cells of a teratoma. Mintz participated in the development of transgenic mice by the incorporation of foreign DNA into a mouse genome.

Format: Articles

Subject: People

Dennis Lo (1963- )

Dennis Lo, also called Yuk Ming Dennis Lo, is a
professor at the Chinese University of Hong Kong in Hong Kong,
China. In 1997, Lo discovered fetal DNA in maternal
plasma, which is the liquid component of a pregnant woman's
blood. By 2002, Lo distinguished the DNA differences between pregnant women
and their fetuses, enabling scientists to identify fetal DNA in pregnant
women's blood. Lo used his discoveries to develop several
non-invasive and prenatal genetic tests, including tests for blood

Format: Articles

Subject: People, Reproduction

Jacques Loeb (1859-1924)

Jacques Loeb experimented on embryos in Europe and the United States at the end of the nineteenth and beginning of the twentieth centuries. Among the first to study embryos through experimentation, Loeb helped found the new field of experimental embryology. Notably, Loeb showed scientists how to create artificial parthenogenesis, thus refuting the idea that spermatozoa alone were necessary to develop eggs into embryos and confirming the idea that the chemical constitution of embryos environment affected their development.

Format: Articles

Subject: People

Carl Gottfried Hartman (1879-1968)

Carl Gottfried Hartman researched the reproductive physiology of opossums and rhesus monkeys. He was the first to extensively study the embryology and physiology of reproduction in opossums when little was known about this mammal. Hartman worked in Texas where opossums, the only marsupial that lives in North America, were abundant. The female opossum delivers her fetal opossums in her pouch, where one can easily observe their development. After studying opossums for thirteen years, Hartman investigated the reproductive physiology of rhesus monkeys, also known as macaques.

Format: Articles

Subject: People

John von Neumann (1903-1957)

John von Neumann was a Hungarian mathematician who made important contributions to mathematics, physics, computer science, and the area of artificial life. He was born in Budapest, Hungary, on 28 December 1903. His mother was Margit von Neumann and his father was Max von Neumann. His work on artificial life focused on the problem of the self-reproduction of machines. Von Neumann initially discussed self-reproducing machines in his Hixon Symposium paper "The General and Logical Theory of Automata" published in 1948.

Format: Articles

Subject: People

Franz Julius Keibel (1861-1929)

Franz Keibel studied the embryos of humans and other animals in Europe at the turn of the twentieth century. He lived and worked in several different parts of Germany and France. Keibel drew illustrations of embryos in many stages of development. Keibel used these illustrations, which he and others in the scientific community called normal plates, to describe the development of organisms in several species of vertebrates.

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

Johannes Holtfreter (1901-1992)

Johannes Holtfreter made important discoveries about the properties of the organizer discovered by Hans Spemann. Although he spent much time away from the lab over many years, he was a productive researcher. His colleagues noted that the time he spent away helped revitalize his ideas. He is credited with the development of a balanced salt medium to allow embryos to develop; the discovery that dead organizer tissue retains inductive abilities; and the development of specification, competence, and distribution of fate maps in the developing frog embryo.

Format: Articles

Subject: People

Julia Bell (1879-1979)

Julia Bell worked in twentieth-century Britain, discovered Fragile X Syndrome, and helped find heritable elements of other developmental and genetic disorders. Bell also wrote much of the five volume Treasury of Human Inheritance, a collection about genetics and genetic disorders. Bell researched until late in life, authoring an original research article on the effects of the rubella virus of fetal development (Congenital Rubella Syndrome) at the age of 80.

Format: Articles

Subject: People

Min Chueh Chang (1908-1991)

As one of the researchers involved in the development of the oral contraceptive pill, Min Chueh Chang helped to revolutionize the birth control movement. Although best known for his involvement with "the pill," Chang also made a number of discoveries throughout his scientific career involving a range of topics within the field of reproductive biology. He published nearly 350 articles in scientific journals.

Format: Articles

Subject: People, Reproduction

Leo Loeb (1869-1959)

Leo Loeb developed an experimental approach to studying cancer and pioneered techniques for tissue culture and in vitro tissue transplantation which impacted early-to-mid twentieth century experimental embryology. Loeb received his medical degree from the University of Zurich in 1897. As part of his doctorate, he completed a thesis on the outcomes of tissue transplantation in guinea pigs. Loeb's thesis inspired a life-long interest in tissue transplantation.

Format: Articles

Subject: People

Lynn Petra Alexander Sagan Margulis (1938-2011)

Lynn Petra Alexander Sagan Margulis was an American biologist, whose work in the mid-twentieth century focused on cells living together in a mutually advantageous relationship, studied cells and mitochondria in the US during the second half of the twentieth century. She developed a theory for the origin of eukaryotic cells, that proposed two kinds of structures found in eukaryotic cells mitochondria in animals, and plastids in plantsÑwere once free-living bacteria that lived harmoniously and in close proximity to larger cells, a scenario called symbiosis.

Format: Articles

Subject: People, Theories

Gail Roberta Martin (1944– )

In the twentieth and early twenty-first centuries, Gail Roberta Martin specialized in biochemistry and embryology, more specifically cellular communication and the development of organs. In 1981, she named any cell taken from inside a human embryo at the blastocyst stage an “embryonic stem cell”. During development, an embryo goes through the blastocyst stage just before it implants in the uterus. Embryonic stem cells are useful for experiments because they are self-renewing and able to develop into almost any cell type in the body.

Format: Articles

Subject: People

Solomon A. Berson (1918-1972)

Solomon A. Berson helped develop the radioimmunoassay (RIA) technique in the US during the twentieth century. Berson made many scientific contributions while working with research partner Rosalyn Yalow at the Bronx Veterans Administration (VA) hospital, in New York City, New York. In the more than twenty years that Berson and Yalow collaborated, they refined the procedures for tracing diagnostic biological compounds using isotope labels.

Format: Articles

Subject: People

Joseph Bolivar DeLee (1869–1942)

Joseph Bolivar DeLee was an obstetrician in the US between the nineteenth and twentieth centuries who advocated for the specialized teaching of medical students in the field of obstetrics to address problems occurring during pregnancy. He claimed obstetricians maintained a wider skillset than midwives, and founded the Chicago Lying-In Hospital to provide affordable obstetric care to women in Chicago, Illinois.

Format: Articles

Subject: People

William Bateson (1861-1926)

At the turn of the twentieth century, William Bateson studied organismal variation and heredity of traits within the framework of evolutionary theory in England. Bateson applied Gregor Mendel's work to Charles Darwin's theory of evolution and coined the term genetics for a new biological discipline. By studying variation and advocating Mendelian genetics, Bateson furthered the field of genetics, encouraged the use of experimental methodology to study heredity, and contributed to later theories of genetic inheritance.

Format: Articles

Subject: People

Rosalyn Sussman Yalow (1921-2011)

Rosalyn Sussman Yalow co-developed the radioimmunoassay (RIA), a method used to measure minute biological compounds that cause immune systems to produce antibodies. Yalow and research partner Solomon A. Berson developed the RIA in the early 1950s at the Bronx Veterans Administration (VA) Hospital, in New York City, New York. Yalow and Berson's methods expanded scientific research, particularly in the medical field, and contributed to medical diagnostics. For this achievement, Yalow received the Nobel Prize in Physiology or Medicine in 1977.

Format: Articles

Subject: People

John George Children (1777–1852)

John George Children described several species of insects and animals while working at the British Museum in London, England, in the eighteenth and nineteenth centuries. Children also conducted research on chemical batteries called voltaic cells and briefly studied and manufactured gunpowder. One of the species he described, the Children’s python, or Antaresia children, was used in the twenty-first century as the subject of experiments that involved the biological cost of reproduction in snakes.

Format: Articles

Subject: People

Samuel Randall Detwiler (1890-1957)

Samuel Randall Detwiler was an embryologist who studied neural development in embryos and vertebrate retinas. He discovered evidence for the relationship between somites and spinal ganglia, that transplanted limbs can be controlled by foreign ganglia, and the plasticity of ganglia in response to limb transplantations. He also extensively studied vertebrate retinas during and after embryonic development.

Format: Articles

Subject: People