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"The linear arrangement of six sex-linked factors in drosophila, as shown by their mode of association” (1913), by Alfred Henry Sturtevant

In 1913, Alfred Henry Sturtevant published the results of experiments in which he showed how genes are arranged along a chromosome. Sturtevant performed those experiments as an undergraduate at Columbia University, in New York, New York, under the guidance of Nobel laureate Thomas Hunt Morgan. Sturtevant studied heredity using Drosophila, the common fruit fly. In his experiments, Sturtevant determined the relative positions of six genetic factors on a fly’s chromosome by creating a process called gene mapping.

Format: Articles

Subject: Experiments, Publications

Camillo Golgi's Black Reaction for Staining Neurons

In 1873 Italy, Camillo Golgi created the black reaction technique, which enabled scientists to stain and view the structure of neurons, the specialized cells that compose the nervous system. During the nineteenth century, scientists were studying cells and proposed cell theory, which describes the basic characteristics of cells as fundamental units of life. However, cell theory struggled to explain neurons as they are specialized cells and more complex in structure than cells of other tissues.

Format: Articles

Subject: Technologies

Endometriosis

Endometriosis is a medical condition that involves abnormal growths of tissue resembling the endometrium, which is the tissue that lines the inside of the uterus. Those growths, called endometrial lesions, typically form outside the uterus, but can spread to other reproductive organs such as ovaries and fallopian tubes. Endometrial lesions swell and bleed during menstruation, which can cause painful and heavy menstruation, as well as infertility.

Format: Articles

Subject: Disorders, Reproduction, Theories

Albrecht von Haller (1708-1777)

Victor Albrecht von Haller was an 18th century scientist who did extensive work in the life sciences, including anatomy and physiology, botany, and developmental biology. His embryological work consisted of experiments in understanding the process of generation, and led him to adopt the model of preformationism called ovism (the idea that the new individual exists within the maternal egg prior to conception). Haller was born in Bern, Switzerland, on 16 October, 1708. His mother was Anna Maria Engel, and his father was Niklaus Emanuel Haller.

Format: Articles

Subject: People

The Discovery of Fetal Alcohol Syndrome

The term Fetal Alcohol Syndrome (FAS) was first published in 1973 in an article published in the British medical journal The Lancet. In that article, a group of pediatricians and psychiatrists at the University of Washington Medical School helped to define the morphological defects and developmental delays that can affect children born to alcoholic mothers. Those observations include pre- and post-natal growth deficiencies, minor facial abnormalities, and damage to the developing brain that can result in behavioral, learning, and cognitive abnormalities.

Format: Articles

Subject: Disorders, Reproduction

The Neuron Doctrine (1860-1895)

The neuron doctrine is a concept formed during the turn of the twentieth century that describes the properties of neurons, the specialized cells that compose the nervous system. The neuron doctrine was one of two major theories on the composition of the nervous system at the time. Advocates of the neuron doctrine claimed that the nervous system was composed of discrete cellular units. Proponents of the alternative reticular theory, on the other hand, argued that the entire nervous system was a continuous network of cells, without gaps or synapses between the cells.

Format: Articles

Subject: Theories

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

The Effects of Thalidomide on Embryonic Development

Embryogenesis is an intricate process that can easily be disrupted by means of teratogenic agents. Some of these agents target the embryonic period's "window of susceptibility," three to eight weeks after a pregnant woman's last menstruation, when the highest degree of sensitivity to embryonic cell differentiation and organ formation occurs. The embryonic period or critical period is when most organ systems form, whereas the fetal period, week eight to birth, involves the growth and modeling of the organ systems.

Format: Articles

Subject: Processes, Disorders

Ovum Humanum: Growth, Maturation, Nourishment, Fertilization and Early Development (1960), by Landrum Brewer Shettles

Ovum Humanum was written and compiled by Dr. Landrum Brewer Shettles while he worked as a doctor in New York. The publication contains an atlas of photographs of the human egg cell that Shettles took while working at Columbia Presbyterian Hospital in New York City. Stechert-Hafner, Inc, a publishing company based in New York City, published the book in 1960. The book presents a collection of color photographs that shows detail of the human egg that had never been seen before, providing a reference for scientists and doctors that documented the anatomy of these cells.

Format: Articles

Subject: Publications, Reproduction

Percivall Pott (1714-1788)

Percivall Pott was a physician in England during the eighteenth century who identified soot as the cause of chimney sweeps' scrotal cancer, later called testicular cancer. In the 1770s, Pott observed that scrotal cancer commonly afflicted chimney sweeps, the young boys sent up into chimneys to clean away the soot left over from fires, and he hypothesized that the soot inside chimneys might cause that type of cancer. Pott was one of the first doctors to identify some environmental factor as causing cancer.

Format: Articles

Subject: People

Camillo Golgi (1843–1926)

Camillo Golgi studied the central nervous system during the late nineteenth and early twentieth centuries in Italy, and he developed a staining technique to visualize brain cells. Called the black reaction, Golgi’s staining technique enabled him to see the cellular structure of brain cells, called neurons, with much greater precision. Golgi also used the black reaction to identify structures within animal cells like the internal reticular apparatus that stores, packs, and modifies proteins, later named the Golgi apparatus in his honor.

Format: Articles

Subject: People

“Epidemiology of Surgically Managed Pelvic Organ Prolapse and Urinary Incontinence” (1997), by Ambre L. Olsen, Virginia J. Smith, John O. Bergstrom, Joyce C. Colling, and Amanda L. Clark

In 1997, physicians and researchers Ambre Olsen, Virginia Smith, John Bergstrom, Joyce Colling, and Amanda Clark published, “Epidemiology of Surgically Managed Pelvic Organ Prolapse and Urinary Incontinence,” in the journal Obstetrics and Gynecology. In their article, the authors retrospectively analyzed data from patients who underwent surgery for pelvic organ prolapse or urinary incontinence two years prior in 1995. Often due to a weakening of or damage to their pelvic muscles, women with pelvic organ prolapse can experience a descent of pelvic organs into the lower pelvis and vagina.

Format: Articles

Subject: Publications, Disorders

John Tyler Bonner (1920- )

The establishment and growth of developmental-evolutionary biology owes a great debt to the work of John Tyler Bonner. Bonner's studies of cellular slime molds have shed light on some of the big questions of biology including the origins of multicellularity and the nature of morphogenesis. The second child of Lilly Marguerite Stehli and Paul Bonner, John Tyler was born 12 May 1920 in New York City and spent his early years in Locust Valley, Long Island (late 1920s), France (1930), and London (1932).

Format: Articles

Subject: People

Fruit Fly Life Cycle

Fruit flies of the species Drosophila melanogaster develop from eggs to adults in eight to ten days at 25 degrees Celsius. They develop through four primary stages: egg, larva, pupa, and adult. When in the wild, female flies lay their fertilized eggs in rotting fruit or other decomposing material that can serve as food for the larvae. In the lab, fruit flies lay their fertilized eggs in a mixture of agar, molasses, cornmeal, and yeast. After roughly a day, each egg hatches into a larva.

Format: Graphics

Subject: Theories, Processes, Organisms

Molecular Epigenetics and Development: Histone Conformations, DNA Methylation and Genomic Imprinting

Introduced by Conrad Hal Waddington in 1942, the concept of epigenetics gave scientists a new paradigm of thought concerning embryonic development, and since then has been widely applied, for instance to inheritable diseases, molecular technologies, and indeed the human genome as a whole. A genome contains an embedded intricate coding template that provides a means of genetic expression from the initial steps of embryonic development until the death of the organism. Within the genome there are two prominent components: coding (exons) and non-coding (introns) sequences.

Format: Articles

Subject: Theories

"Developmental Effects of Endocrine-Disrupting Chemicals in Wildlife and Humans" (1993), by Theo Colborn, Frederick S. vom Saal, and Ana M. Soto

Developmental Effects of Endocrine-Disrupting Chemicals in Wildlife and Humans, was published in 1993 in Environmental Health Perspectives. In the article, the authors present an account of two decades' worth of scientific research that describes the effects of certain pollutants on the health of wildlife, domestic animals, and humans, particularly when exposure takes place during embryonic growth. The term endocrine disruptor was coined in the article to describe the chemical pollutants that target the development and function of the endocrine system.

Format: Articles

Subject: Publications

Cornelia Isabella Bargmann (1961- )

Cornelia Isabella Bargmann studied the relationship between genes, neural circuits, and behavior in the roundworm Caenorhabditis elegans (C. elegans) during the twentieth and twenty-first centuries in the US. Bargmann’s research focused on how the sense of smell (olfaction) in the nematode word Caenorhabditis elegans. She provided a model to study how neural circuits develop and function in the human brain, as the genetic regulatory pathways are similar.

Format: Articles

Subject: People

“HPV in the Etiology of Human Cancer” (2006) by Nubia Muñoz, Xavier Castellsagué, Amy Berrington de González, and Lutz Gissmann

In 2006, the article “HPV in the Etiology of Human Cancer,” hereafter “HPV and Etiology,” by Nubia Muñoz, Xavier Castellsagué, Amy Berrington de González, and Lutz Gissmann, appeared as the first chapter in the twenty-fourth volume of the journal Vaccine. Muñoz and colleagues discuss the role of the Human Papillomavirus, or HPV, in uterine cervical cancers. The authors introduce the mechanisms of HPV infection that lead to genital and non-genital cancers, establishing a link between HPV and multiple human cancers.

Format: Articles

Subject: Disorders, Processes, Technologies

Exchange Transfusion for Jaundiced Newborns in the United States

Exchange transfusion is the replacement of blood from newborn infants with elevated bilirubin level in their blood stream with donor blood containing normal bilirubin levels. Newborn infants that experience jaundice, the yellowing of the skin and eyes, have a buildup of bilirubin, a chemical that occurs during red blood cell breakdown, or hemolysis. Exchange transfusion is a therapy developed throughout the 1940s by Louis Diamond and a group of surgeons at the Children’s Medical Center in Boston, Massachusetts.

Format: Articles

Subject: Technologies

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

Alexis Carrel's Immortal Chick Heart Tissue Cultures (1912-1946)

In an effort to develop tissue culture techniques for long-term tissue cultivation, French surgeon and biologist Alexis Carrel, and his associates, produced and maintained a series of chick heart tissue cultures at the Rockefeller Institute in New York City. From 1912 to 1946, this series of chick heart tissue cultures remained alive and dividing. Since the duration of this culture greatly exceeded the normal chick life span, the cells were deemed immortal.

Format: Articles

Subject: Experiments

Johns Hopkins Fertility Center

Johns Hopkins Medical Center, located in Baltimore, Maryland, opened in 1889; its associated medical school opened four years later. Today the hospital, a leading research center, contains many departments, including a fertility center that is renowned for taking on difficult cases that have been rejected by other fertility clinics. The fertility center was founded by physician Georgeanna Seegar Jones in 1939 as the Division of Reproductive Endocrinology in the gynecology department. The division expanded once formal training in reproductive endocrinology began in 1973.

Format: Articles

Subject: Organizations, Reproduction

“Miscarriage of Medicine: The Growth of Catholic Hospitals and the Threat to Reproductive Health Care” (2013), by Lois Uttley, Sheila Reynertson, Larraine Kenny, and Louise Melling

In 2013, Lois Uttley, Sheila Reynertson, Larraine Kenny, and Louise Melling published “Miscarriage of Medicine: The Growth of Catholic Hospitals and the Threat to Reproductive Health Care,” in which they analyzed the growth of Catholic hospitals in the United States from 2001 to 2011 and the impact those hospitals had on reproductive health care. In the US, Catholic hospitals are required to abide by the US Catholic Church's Ethical Guidelines for Health Care Providers, also called the Directives.

Format: Articles

Subject: Publications

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

“Fetal Programming and Adult Health” (2001), by Kevin M. Godfrey and David J.P. Barker

In 2001, Kevin M. Godfrey and David J.P. Barker published the article “Fetal Programming and Adult Health” in Public Health Nutrition, where they identified the significance of maternal nutrition during pregnancy to healthy offspring development. The authors describe the effects of maternal nutrition on fetal programming of cardiovascular disease. Fetal programming is when a specific event during pregnancy has effects on the fetus long after birth.

Format: Articles

Subject: Publications, Theories