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Pfeffer Cell Apparatus

The Pfeffer Zelle (Pfeffer Cell Apparatus), invented by Wilhelm Pfeffer in 1877, measured the minimum pressure needed to prevent a pure solvent from passing into a solution across a semi-permeable membrane, called osmotic pressure. The apparatus provided Pfeffer with a way to quantitatively measure osmotic pressure. Pfeffer devised the apparatus in the 1870s at the University of Basel in Basel, Switzerland, and he described the Pfeffer Cell Apparatus in his 1877 book Osmotische Untersuchungen: Studien Zur Zellmechanik (Osmotic Investigations: Studies on Cell Mechanics).

Format: Articles

"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

The Hedgehog Signaling Pathway in Vertebrates 

The hedgehog signaling pathway is a mechanism that regulates cell growth and differentiation during embryonic development, called embryogenesis, in animals. The hedgehog signaling pathway works both between cells and within individual cells.

Format: Articles

Subject: Theories

Simat Corp v. Arizona Health Care Cost Containment System (2002)

In the 2002 case Simat Corp v. Arizona Health Care Containment System, the Arizona Supreme Court ruled that the Arizona Health Care Containment System must pay for abortions when they are necessary to preserve the health of pregnant women in the system. In the case, the Court ruled that the Arizona Revised Statutes 35-196.02 and the Arizona Health Care Containment System (AHCCCS) policies, which banned public funds from being used for abortions, were unconstitutional. AHCCCS is Arizona's Medicaid insurance system, which enables low-income residents to receive medical care.

Format: Articles

Subject: Legal

Tucson Woman's Clinic v. Eden (2004)

The case Tucson Woman's Clinic v. Eden (2004) established that some of Arizona's abortion clinic laws violated physicians' and patients' rights to privacy, and it required those laws to be rewritten. The laws required most abortion providers to be licensed with the Arizona Department of Health Services and to submit to all the regulations the Department established for abortion clinics. The regulations allowed the state to search abortion clinics without warrants and to access patient records and ultrasound prints, among other provisions.

Format: Articles

Subject: Legal

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

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

Human Papillomavirus (HPV) Strains 16 and 18

The Human Papillomavirus (HPV) strains 16 and 18 are the two most common HPV strains that lead to cases of genital cancer. HPV is the most commonly sexually transmitted disease, resulting in more than fourteen million cases per year in the United States alone. When left untreated, HPV leads to high risks of cervical, vaginal, vulvar, anal, and penile cancers. In 1983 and 1984 in Germany, physician Harald zur Hausen found that two HPV strains, HPV-16 and HPV-18, caused cervical cancer in women. In the early twenty first century, pharmaceutical companies Merck & Co.

Format: Articles

Subject: Theories

Prenatal Care (1913), by Mary Mills West

Prenatal Care is an educational booklet written by Mary Mills West of the US Children’s Bureau and published by the US Government Printing Office in 1913. The Bureau distributed West’s booklets in response to their field studies on infant mortality, which found that lack of access to accurate health and hygiene information put women and infants at greater than normal risk of death or disease. In Prenatal Care, West offers advice on nutrition, exercise, and personal hygiene during pregnancy and describes the processes of labor and birth.

Format: Articles

Subject: Outreach, Publications

Sheppard-Towner Maternity and Infancy Protection Act (1921)

In November 1921, US Congress passed the National Maternity and Infancy Protection Act, also called the Sheppard-Towner Act. The Act provided federal funds to states to establish programs to educate people about prenatal health and infant welfare. Advocates argued that it would curb the high infant mortality rate in the US.

Format: Articles

Subject: Legal, Outreach

Where Are My Children? (1916)

Where Are My Children? is an anti-abortion silent film released in the United States on 16 April 1916. The film was directed by Lois Weber and Phillips Smalley and produced by Universal Film Manufacturing Company/Lois Weber Productions in Universal City, California. In the film, Weber tells a story of an attorney who wants to have children and raise a family, but his wife chooses to abort her pregnancies, fearing that having children will ruin her social activities. In the early 1900s, information about contraception was not freely available or legal to obtain.

Format: Articles

Matthias Jacob Schleiden (1804–1881)

Matthias Jacob Schleiden helped develop the cell theory in Germany during the nineteenth century. Schleiden studied cells as the common element among all plants and animals. Schleiden contributed to the field of embryology through his introduction of the Zeiss microscope lens and via his work with cells and cell theory as an organizing principle of biology.

Format: Articles

Subject: People

Sonja Vernes, et al.'s Experiments On the Gene Networks Affected by the Foxp2 Protein (2011)

In 2011, Sonja Vernes and Simon Fisher performed a series of experiments to determine which developmental processes are controlled by the mouse protein Foxp2. Previous research showed that altering the Foxp2 protein changed how neurons grew, so Vernes and Fisher hypothesized that Foxp2 would affect gene networks that involved in the development of neurons, or nerve cells. Their results confirmed that Foxp2 affected the development of gene networks involved in the growth of neurons, as well as networks that are involved in cell specialization and cell communication.

Format: Articles

Subject: Experiments

Planned Parenthood Committee of Phoenix v. Maricopa County (1962)

In the 1962 case Planned Parenthood Committee of Phoenix v. Maricopa County, the Arizona Supreme Court ruled that Arizona Revised Statute 13-213, which banned the public advertising of contraceptive or abortion medication or services, was constitutional. However, the court also ruled that that Arizona Revised Statute 13-213 did not apply to Planned Parenthood's distribution of contraceptive information, allowing Planned Parenthood to continue distributing the information.

Format: Articles

Subject: Legal

Human Papillomavirus (HPV) Strains 16 and 18

The Human Papillomavirus (HPV) strains 16 and 18 are the two most common HPV strains that lead to cases of genital cancer. HPV is the most commonly sexually transmitted disease, resulting in more than fourteen million cases per year in the United States alone. When left untreated, HPV leads to high risks of cervical, vaginal, vulvar, anal, and penile cancers. In 1983 and 1984 in Germany, physician Harald zur Hausen found that two HPV strains, HPV-16 and HPV-18, caused cervical cancer in women. In the early twenty first century, pharmaceutical companies Merck & Co.

Format: Articles

Subject: Theories

HIP Randomized Breast Cancer Screening Trial (1963–1982)

From 1963 to 1982, researchers in New York City, New York, carried out a randomized trial of mammography screening. Mammography is the use of X-ray technology to find breast cancer at early stages. The private insurance company Health Insurance Plan of Greater New York, or HIP, collaborated with researchers Sam Shapiro, Philip Strax, and Louis Venet on the trial. The researchers’ goal was to determine whether mammography screening reduced breast cancer mortality in women. The study included sixty thousand women aged forty to sixty-four.

Format: Articles

Subject: Experiment

“Screening for Breast Cancer with Mammography” (2013), by Peter Gøtzsche and Karsten Jørgensen

Screening for Breast Cancer with Mammography is a Cochrane systematic review originally published by Peter Gøtzsche and Karsten Jørgensen in 2001 and updated multiple times by 2013. In the 2013 article, the authors discuss the reliability of the results from different clinical trials involving mammography and provide their conclusions about whether mammography screening is useful in preventing deaths from breast cancer.

Format: Articles

Subject: Publications

“Infant Survival After Cesarean Section for Trauma” (1996), by John A. Morris, Jr. et al.

In the May 1996 edition of The Annals of Surgery, John A. Morris and his collaborators published “Infant Survival After Cesarean Section for Trauma,” in which they evaluate the use of emergency cesarean sections for the treatment of pregnant trauma patients. During a cesarean section, a physician removes a fetus from a pregnant woman through an incision in her abdomen and uterus. When a pregnant woman experiences trauma, physicians can perform an emergency cesarean section to remove the fetus and administer medical treatments that would not be possible while the woman is pregnant.

Format: Articles

Subject: Publications

Shoukhrat Mitalipov and Masahito Tachibana's Mitochondrial Gene Replacement Therapy Technique

In 2009, Shoukhrat Mitalipov, Masahito Tachibana, and their team of researchers developed the technology of mitochondrial gene replacement therapy to prevent the transmission of a mitochondrial disease from mother to offspring in primates. Mitochondria contain some of the body's genetic material, called mitochondrial DNA. Occasionally, the mitochondrial DNA possesses mutations.

Format: Articles

Subject: Technologies

Physician Labeling Rule (2006)

In 2006, the United States Food and Drug Administration, or FDA, published the “Requirements on Content and Format of Labeling for Human Prescription Drug and Biological Products,” also called the Physician Labeling Rule, to improve the safety and efficacy of prescription drugs and drug products. Within the Physician Labeling Rule, the FDA includes a section titled “Use in Specific Populations” or Section 8, which refers to drugs used by pregnant women, lactating women, and people of reproductive capacity.

Format: Articles

Subject: Legal

Planned Parenthood v. Danforth (1976)

On 1 July 1976, the US Supreme Court decided in the case Planned Parenthood v. Danforth that provisions of a Missouri law regulating abortion care were unconstitutional. That law, House Bill 1211, restricted abortion care by requiring written consent for each abortion procedure from the pregnant woman as written consent of the woman’s husband if she was married, or the written consent of her parents if she was unmarried and younger than eighteen. House Bill 1211 also required that physicians make efforts to preserve the lives of aborted fetuses.

Format: Articles

Subject: Legal

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

Mitochondrial DNA (mtDNA)

Mitochondrial DNA (mtDNA) is located outside the nucleus in the liquid portion of the cell (cytoplasm) inside cellular organelles called Mitochondria. Mitochondria are located in all complex or eukaryotic cells, including plant, animal, fungi, and single celled protists, which contain their own mtDNA genome. In animals with a backbone, or vertebrates, mtDNA is a double stranded, circular molecule that forms a circular genome, which ranges in size from sixteen to eighteen kilo-base pairs, depending on species. Each mitochondrion in a cell can have multiple copies of the mtDNA genome.

Format: Articles

Subject: Theories

Ernest John Christopher Polge (1926-2006)

Twentieth-century researcher Ernest John Christopher Polge studied the reproductive processes of livestock and determined a method to successfully freeze, thaw, and utilize viable sperm cells to produce offspring in animals. In 1949, Polge identified glycerol as a cryoprotectant, or a medium that enables cells to freeze without damaging their cellular components or functions. Several years later, Polge used glycerol in a freezing process called vitrification, which enabled him to freeze poultry sperm, thaw that sperm, and use it to fertilize vertebrate embryos.

Format: Articles

Subject: People

Aristotle (384-322 BCE)

Aristotle studied developing organisms, among other things, in ancient Greece, and his writings shaped Western philosophy and natural science for greater than two thousand years. He spent much of his life in Greece and studied with Plato at Plato's Academy in Athens, where he later established his own school called the Lyceum. Aristotle wrote greater than 150 treatises on subjects ranging from aesthetics, politics, ethics, and natural philosophy, which include physics and biology. Less than fifty of Aristotle's treatises persisted into the twenty-first century.

Format: Articles

Subject: People