Search

Displaying 151 - 175 of 450 items.

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

Management of Myelomeningocele Study Clinical Trial (2003–2010)

From February 2003 to December 2010, researchers of the Management of Myelomeningocele Study, or MOMS, clinical trial compared the safety and efficacy of different treatments for a specific type of spina bifida, called myelomeningocele. Myelomeningocele, the most frequent and severe form of spina bifida, is a condition in which the bony spinal column does not develop correctly, which causes an opening of the spine, exposure of the spinal cord, and formation of a small sac containing cerebrospinal fluid.

Format: Articles

Subject: Experiments

Serial Cultivation of Human Diploid Cells in the Lab (1958–1961) by Leonard Hayflick and Paul S. Moorhead

From 1958 to 1961, Leonard Hayflick and Paul Moorhead in the US developed a way in the laboratory to cultivate strains of human cells with complete sets of chromosomes. Previously, scientists could not sustain cell cultures with cells that had two complete sets of chromosomes like normal human cells (diploid). As a result, scientists struggled to study human cell biology because there was not a reliable source of cells that represented diploid human cells. In their experiments, Hayflick and Moorhead created lasting strains of human cells that retained both complete sets of chromosomes.

Format: Articles

Subject: Experiments

"The Adaptive Significance of Temperature-Dependent Sex Determination in a Reptile" (2008), by Daniel Warner and Richard Shine

In 2008 researchers Daniel Warner and Richard Shine tested the Charnov-Bull model by conducting experiments on the Jacky dragon (Amphibolurus muricatus), in Australia. Their results showed that temperature-dependent sex determination(TSD) evolved in this species as an adaptation to fluctuating environmental temperatures. The Charnov-Bull model, proposed by Eric Charnov and James Bull in 1977, described the evolution of TSD, although the model was, for many years, untested.

Format: Articles

Subject: Experiments

Temperature-Dependent Sex Determination in Reptiles

The sex of a reptile embryo partly results from the production of sex hormones during development, and one process to produce those hormones depends on the temperature of the embryo's environment. The production of sex hormones can result solely from genetics or from genetics in combination with the influence of environmental factors. In genotypic sex determination, also called genetic or chromosomal sex determination, an organism's genes determine which hormones are produced.

Format: Articles

Subject: Experiments

Amniocentesis

Amniocentesis is a test used for prenatal diagnosis of inherited diseases, Rh incompatibility, neural tube defects, and lung maturity. Normally performed during the second trimester of a pregnancy, this invasive procedure allows the detection of health problems in the fetus as early as fifteen weeks gestation. Although amniocentesis does carry some significant risks, the medical community commonly accepts it as a safe and useful procedure.

Format: Articles

Subject: Technologies, Reproduction

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

Evangelium Vitae (1995), by Pope John Paul II

The encyclical entitled "Evangelium Vitae," meaning "The Gospel of Life," was promulgated on 25 March 1995 by Pope John Paul II in Rome, Italy. The document was written to reiterate the view of the Roman Catholic Church on the value of life and to warn against violating the sanctity of life. The document focuses on right to life issues including abortion, birth control, and euthanasia, but also touches on other concepts relevant to embryology, such as contraception, in vitro fertilization, sterilization, embryonic stem cell research, and fetal experimentation.

Format: Articles

Subject: Religion, Reproduction

Hematopoietic Stem Cell Transplantation

The purpose of regenerative medicine, especially tissue engineering, is to replace damaged tissue with new tissue that will allow the body to resume normal function. The uniqueness of tissue engineering is that it can restore normal structure in addition to repairing tissue function, and is often accomplished using stem cells. The first type of tissue engineering using stem cells was hematopoietic stem cell transplantation (HSCT), a surgical procedure in which hematopoietic stem cells (HSCs) are infused into a host to treat a variety of blood diseases, cancers, and immunodeficiencies.

Format: Articles

Subject: Technologies

Leon Chesley (1908-2000)

Leon Chesley studied hypertension, or high blood pressure, in pregnant women during the mid-twentieth century. Chesley studied preeclampsia and eclampsia, two hypertensive disorders found in approximately five percent of all US pregnancies. In New Jersey and New York, Chesley devoted over forty years to researching preeclampsia and eclampsia. Chesley conducted several long-term studies using the same group of women beginning from their pregnancies.

Format: Articles

Subject: People, Reproduction

Stem Cells

According to the US National Institutes of Health (NIH), the standard American source on stem cell research, three characteristics of stem cells differentiate them from other cell types: (1) they are unspecialized cells that (2) divide for long periods, renewing themselves and (3) can give rise to specialized cells, such as muscle and skin cells, under particular physiological and experimental conditions. When allowed to grow in particular environments, stem cells divide many times. This ability to proliferate can yield millions of stem cells over several months.

Format: Articles

Subject: Processes

Walter Edward Dandy (1886-1946)

Walter Edward Dandy studied abnormalities in the developing human brain in the United States in the twentieth century. He collaborated with pediatrician Kenneth Blackfan to provide the first clinical description of Dandy-Walker Syndrome, a congenital brain malformation in which the medial part of the brain, called the cerebellar vermis, is absent. Dandy also described the circulation of cerebral spinal fluid, the clear, watery fluid that surrounds and cushions the brain and spinal cord.

Format: Articles

Subject: People

Priscilla White (1900–1989)

Priscilla White studied
the treatment of diabetes in mothers, pregnant women, and
children during the twentieth century in the US. White began
working with children with Type 1 diabetes in 1924 at Elliott
Proctor Joslin’s practice in Boston, Massachusetts. Type 1
diabetes is an incurable disease where the pancreas produces
little to no insulin. Insulin is a hormone that allows the body
to use sugar from food for energy and store sugars for future
use. Joslin and White co-authored many publications on children

Format: Articles

Subject: People

Gunther von Hagens' Plastination Technique

Plastination is a technique for preserving tissues, organs, and whole bodies for medical purposes and public display. Gunther von Hagens invented a form of the method in 1977 at Heidelberg University in Heidelberg, Germany after observing medical students struggle working with cadavers that quickly decomposed. Von Hagens' body models, referred to as plastinates, have since become widely used educational tools not only for those studying anatomy and medicine, but also for the general public.

Format: Articles

Subject: Technologies

The Silent Scream (1984), by Bernard Nathanson, Crusade for Life, and American Portrait Films

The Silent Scream is an anti-abortion film released in 1984 by American Portrait Films, then based in Brunswick, Ohio. The film was created and narrated by Bernard Nathanson, an obstetrician and gynecologist from New York, and it was produced by Crusade for Life, an evangelical anti-abortion organization. In the video, Nathanson narrates ultrasound footage of an abortion of a twelve-week-old fetus, claiming that the fetus opened its mouth in what Nathanson calls a silent scream during the procedure.

Format: Articles

Subject: Outreach, Reproduction

"The Limited In Vitro Lifetime of Human Diploid Cell Strains" (1964), by Leonard Hayflick

Leonard Hayflick in the US during the early 1960s showed that normal populations of embryonic cells divide a finite number of times. He published his results as 'The Limited In Vitro Lifetime of Human Diploid Cell Strains' in 1964. Hayflick performed the experiment with WI-38 fetal lung cells, named after the Wistar Institute, in Philadelphia, Pennsylvania, where Hayflick worked. Frank MacFarlane Burnet, later called the limit in capacity for cellular division the Hayflick Limit in 1974.

Format: Articles

Subject: Experiments

Thesis: Informed Consent Laws for Abortion: What Do Women Have a "Right to Know?

The objective of this project was to determine the importance of informed consent laws to achieving the larger goal of dismantling the right to abortion. I found that informed consent counseling materials in most states contain a full timeline of fetal development, along with information about the risks of abortion, the risks of childbirth, and alternatives to abortion. In addition, informed consent laws for abortion are based on model legislation called the “Women’s Right to Know Act” developed by Americans United for Life (AUL).

Format: Essays and Theses

Subject: Legal, Ethics

James G. Wilson's Six Principles of Teratology

James Graves Wilson's six principles of teratology, published in 1959, guide research on teratogenic agents and their effects on developing organisms. Wilson's six principles were inspired by Gabriel Madeleine Camille Dareste's five principles of experimental teratology published in 1877. Teratology is the study of birth defects, and a teratogen is something that either induces or amplifies abnormal embryonic or fetal development and causes birth defects.

Format: Articles

Subject: Processes, Reproduction

"The Familial Factor in Toxemia of Pregnancy" (1968), by Leon C. Chesley, et al.

In the 1950s and 1960s, researchers Leon Chesley, John Annitto, and Robert Cosgrove investigated the possible familial factor for the conditions of preeclampsia and eclampsia in pregnant women. Preeclampsia and eclampsia, which are related to high blood pressure, have unknown causes and affect at least five percent of all pregnancies.

Format: Articles

Subject: Reproduction, Experiments, Disorders

Robert Guthrie (1916–1995)

Robert Guthrie developed a method to test infants for phenylketonuria (PKU) in the United States during the twentieth century. PKU is an inherited condition that causes an amino acid called phenylalanine to build to toxic levels in the blood. Untreated, PKU causes mental disabilities. Before Guthrie’s test, physicians rarely tested infants for PKU and struggled to diagnosis it. Guthrie’s test enabled newborns to be quickly and cheaply screened at birth and then treated for PKU if necessary, preventing irreversible neurological damage.

Format: Articles

Subject: People

Norbert Freinkel (1926–1989)

During the twentieth century, Norbert Freinkel studied hormones and diabetes in the US. Freinkel conducted many experiments that enabled him to determine the factors that influence hormones of the thyroid gland to bind to proteins and to determine the effects that those thyroid hormones have on surrounding tissues. Furthermore, Freinkel researched gestational diabetes, which is diabetes that occurs for the first time during a women’s pregnancy. That type of diabetes is caused by a change in the way a woman’s body responds to insulin, a hormone made in the body.

Format: Articles

Subject: People

"Maternal consumption of peanut during pregnancy is associated with peanut sensitization in atopic infants" (2010), by Scott Sicherer, et al.

In 2010, a team of US researchers concluded that the more peanuts a pregnant woman ate during her pregnancy, the more likely her newborn was to be sensitive to peanuts. They published their results in 2010's "Maternal consumption of peanut during pregnancy is associated with peanut sensitization in atopic infants." The work resulted from the collaboration of Scott Sicherer and Hugh Sampson, both from the Jaffe Food Allergy Institute, Mount Sinai School of Medicine, in New York, New York along with other colleagues.

Format: Articles

Subject: Experiments, Reproduction

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

“Kangaroo Care Is Effective in Diminishing Pain Response in Preterm Neonates” (2003), by Celeste Johnston, Bonnie Stevens, Janet Pinelli, Sharyn Gibbins, Francoise Filion, Anne Jack, Susan Steele, Kristina Boyer, and Annie Veilleux

In the 2003 article “Kangaroo Care Is Effective in Diminishing Pain Response in Preterm Neonates”, Celeste Johnston, Bonnie Stevens, Janet Pinelli, and their colleagues evaluate the effectiveness of the Kangaroo Mother Care position in decreasing the pain response of preterm infants who undergo a heel lance procedure for blood collection. Kangaroo Mother Care is a method of treatment for premature and low birth weight infants that involves exclusive breastfeeding and skin-to-skin contact between a mother and her infant in what is called the kangaroo position.

Format: Articles

Subject: Publications

“Insulin Dependent Diabetes Mellitus: Implications for Male Reproductive Function” (2007), by Ishola Agbaje, Deirdre Rogers, Carmel McVicar, Neil McClure, Albert Atkinson, Con Mallidis, and Sheena Lewis

In 2007, Ishola Agbaje, Deirdre Rogers, Carmel McVicar, Neil McClure, Albert Atkinson, Con Mallidis, and Sheena Lewis published “Insulin Dependent Diabetes Mellitus: Implications for Male Reproductive Function,” hereby “Diabetes Mellitus: Implications,” in the journal Human Reproduction. In their article, the authors explore the effects of elevated blood sugar in the form of diabetes mellitus on the quality of male sperm.

Format: Articles

Subject: Publications, Disorders