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The First Successful Cloning of a Gaur (2000), by Advanced Cell Technology

Advanced Cell Technology (ACT), a stem cell biotechnology company in Worcester, Massachusetts, showed the potential for cloning to contribute to conservation efforts. In 2000 ACT researchers in the United States cloned a gaur (Bos gaurus), an Asian ox with a then declining wild population. The researchers used cryopreserved gaur skin cells combined with an embryo of a domestic cow (Bos taurus). A domestic cow also served as the surrogate for the developing gaur clone.

Format: Articles

Subject: Experiments

Action of MER-25 and of Clomiphene on the Human Ovary (1963)

Between 1958 and 1962, physicians Olive W. Smith, George V. Smith, and Robert W. Kistner performed experiments that demonstrated the effects of the drugs MER-25 and clomiphene citrate on the female human body. MER-25 and clomiphene citrate are drugs that affect estrogen production in women. At the time of the experiment, researchers did not know which organ or organs the drugs affected, the ovaries and/or the anterior pituitary gland.

Format: Articles

Subject: Experiments

"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

"Congenital Club Foot in the Human Fetus" (1980), by Ernesto Ippolito and Ignacio Ponseti

In 1980, Ernesto Ippolito and Ignacio Ponseti published their results on a histological study they performed on congenital club foot in human fetuses. The researchers examined the feet of four aborted fetuses and compared the skeletal tissues from healthy feet to those affected by congenital club foot. Infants born with club foot are born with one or both feet rigidly twisted inwards and upwards, making typical movement painful and challenging.

Format: Articles

Subject: Experiments

The Discovery of p53 Protein

The p53 protein acts as a pivotal suppressor of inappropriate cell proliferation. By initiating suppressive effects through induction of apoptosis, cell senescence, or transient cell-cycle arrest, p53 plays an important role in cancer suppression, developmental regulation, and aging. Its discovery in 1979 was a product of research into viral etiology and the immunology of cancer. The p53 protein was first identified in a study of the role of viruses in cancer through its ability to form a complex with viral tumor antigens.

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

Jennifer Doudna and Emmanuelle Charpentier’s Experiment About the CRISPR/cas 9 System’s Role in Adaptive Bacterial Immunity (2012)

In 2012, Jennifer Doudna, Emmanuelle Charpentier from the University of California, Berkeley, in Berkeley, California, and Umeå University in Umeå, Sweden, along with their colleagues discovered how bacteria use the CRISPR/cas 9 system to protect themselves from viruses. The researchers also proposed the idea of using the CRISPR/cas 9 system as a genome editing tool.

Format: Articles

Subject: Experiments

"Male Development of Chromosomally Female Mice Transgenic for Sry gene" (1991), by Peter Koopman, et al.

Early 1990s research conducted by Peter Koopman, John Gubbay, Nigel Vivian, Peter Goodfellow, and Robin Lovell-Badge, showed that chromosomally female (XX) mice embryos can develop as male with the addition of a genetic fragment from the Y chromosome of male mice. The genetic fragment contained a segment of the mouse Sry gene, which is analogous to the human SRY gene. The researchers sought to identify Sry gene as the gene that produced the testis determining factor protein (Tdf protein in mice or TDF protein in humans), which initiates the formation of testis.

Format: Articles

Subject: Experiments

Harald zur Hausen's Experiments on Human Papillomavirus Causing Cervical Cancer (1976–1987)

From 1977 to 1987, Harald zur Hausen led a team of researchers across several institutions in Germany to investigate whether the human papillomavirus (HPV) caused cervical cancer. Zur Hausen's first experiment tested the hypothesis that HPV caused cervical cancer rather than herpes simplex virus type 2 (HSV-2), the then accepted cause. His second and third experiments detailed methods to identify two previously unidentified HPV strains, HPV 16 and HPV 18, in cervical cancer tumor samples. The experiments showed that HPV 16 and 18 DNA were present in cervical tumor samples.

Format: Articles

Subject: Experiments

Treatment of Anemia during Pregnancy (1931), by Lucy Wills

In 1931, physician Lucy Wills conducted a study of nutritional deficiencies that caused anemia in pregnant women in Bombay, India, later renamed Mumbai. Anemia is a lack of healthy red blood cells in the blood. Wills published the results of her study in the medical article 'Treatment of ‘Pernicious Anaemia of Pregnancy' and 'Tropical Anaemia'' in the British Medical Journal in 1931. Wills's research contributed to knowledge of anemia and the possible causes associated with the disease, such as the symptoms of fatigue and irritability.

Format: Articles

Subject: Experiments

Rock-Menkin Experiments

Dr. John Rock, a doctor of obstetrics and gynecology in Boston, and Miriam Menkin, Rock s hired lab technician, were the first researchers to fertilize a human egg outside of a human body in February of 1944. Their work was published on 4 August 1944 in an issue of Science in an article entitled "In Vitro Fertilization and Cleavage of Human Ovarian Eggs." This experiment marked the first time in history that a human embryo was produced outside of the human body, proving that in vitro fertilization was possible in humans.

Format: Articles

Subject: Experiments, Reproduction

Clinical Tests of Estrogen Injections on Women with Abnormal Menstrual Cycles During the Early 1920s by Jean Paul Pratt and Edgar Allen

In the early twentieth century US, Jean Paul Pratt and Edgar Allen conducted clinical experiments on women who had abnormal menstrual cycles. During the clinical tests, researchers injected the hormone estrogen into their patients to alleviate their menstrual ailments, which ranged from irregular cycles to natural menopause. The hormone estrogen plays a prominent role in the menstrual cycle by signaling the tissue lining the uterus (endometrium) to thicken in preparation for possible pregnancy.

Format: Articles

Subject: Experiments

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

"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

"Transplantation of Living Nuclei from Blastula Cells into Enucleated Frogs' Eggs" (1952), by Robert Briggs and Thomas J. King

In 1952 Robert Briggs and Thomas J. King published their article, "Transplantation of Living Nuclei from Blastula Cells into Enucleated Frogs' Eggs," in the Proceedings of the National Academy of Sciences, the culmination of a series of experiments conducted at the Institute for Cancer Research and Lankenau Hospital Research Institute in Philadelphia, Pennsylvania. In this paper Briggs and King examined whether nuclei of embryonic cells are differentiated, and by doing so, were the first to conduct a successful nuclear transplantation with amphibian embryos.

Format: Articles

Subject: Experiments

The Meselson-Stahl Experiment (1957–1958), by Matthew Meselson and Franklin Stahl

In an experiment later named for them, Matthew Stanley Meselson and Franklin William Stahl in the US demonstrated during the 1950s the semi-conservative replication of DNA, such that each daughter DNA molecule contains one new daughter subunit and one subunit conserved from the parental DNA molecule. The researchers conducted the experiment at California Institute of Technology (Caltech) in Pasadena, California, from October 1957 to January 1958.

Format: Articles

Subject: Processes, Experiments

"A molecular wound response program associated with regeneration initiation in planarians" (2012), by Danielle Wenemoser et al.

In 2012, a team of scientists across the US conducted an experiment to find the mechanism that allowed a group of flatworms, planarians, to regenerate any body part. The group included Danielle Wenemoser, Sylvain Lapan, Alex Wilkinson, George Bell, and Peter Reddien. They aimed to identify genes that are expressed by planarians in response to wounds that initiated a regenerative mechanism. The researchers determined several genes as important for tissue regeneration.

Format: Articles

Subject: Experiments

Digit Regeneration Is Regulated by Msx1 and BMP4 in Fetal Mice (2003), by Manjong Han et al.

In the early 2000s, Manjong Han, Xiaodang Yang, Jennifer Farrington, and Ken Muneoka investigated how genes and proteins in fetal mice (Mus musculus) influenced those fetal mice to regenerate severed toes at Tulane University in New Orleans, Louisiana. The group used hind limbs from mice to show how the gene Msx1 (Homeobox 7) functions in regenerating amputated digits.

Format: Articles

Subject: Experiments

Hox Genes and the Evolution of Vertebrate Axial Morphology Experiment (1995)

In 1995, researchers Ann Burke, Craig Nelson, Bruce Morgan, and Cliff Tabin in the US studied the genes that regulate the construction of vertebra in developing chick and mouse embryos, they showed similar patterns of gene regulation across both species, and they concluded that those patterns were inherited from an ancestor common to all vertebrate animals. The group analyzed the head-to-tail (anterior-posterior) axial development of vertebrates, as the anterior-posterior axis showed variation between species over the course of evolutionary time.

Format: Articles

Subject: Experiments

The Genetic Control and Cytoplasmic Expression of 'Inducibility' in the synthesis of B-galactosidase" (1959), by Arthur B. Pardee, Francois Jacob, and Jacques Monod

Between 1957 and 1959, Arthur Pardee, Francois Jacob, and Jacques Monod conducted a set of experiments at the Pasteur Institute in Paris, France, that was later called the PaJaMa Experiments, a moniker derived from the researchers' last names. In these experiments, they described how genes of a species of single-celled bacteria, called Escherichia coli (E. coli), controlled the processes by which enzymes were produced in those bacteria.

Format: Articles

Subject: Experiments

"Human Factor IX Transgenic Sheep Produced by Transfer of Nuclei from Transfected Fetal Fibroblasts" (1997), by Angelika E. Schnieke, et al.

In the 1990s, researchers working at the Roslin Institute in Edinburgh, Scotland, performed cloning experiments in collaboration with PPL Therapeutics in Roslin, Scotland, on human coagulation factor IX, a protein. The team of scientists used the methods identified during the Dolly experiments to produce transgenic livestock capable of producing milk containing human blood clotting factor IX, which helps to treat a type of hemophilia.

Format: Articles

Subject: Experiments

"Generation of Induced Pluripotent Stem Cells without Myc from Mouse and Human Fibroblasts" (2007), by Masato Nakagawa et al.

In November 2007, Masato Nakagawa, along with a number of other researchers including Kazutoshi Takahashi, Keisuke Okita, and Shinya Yamanaka, published "Generation of Induced Pluripotent Stem Cells without Myc from Mouse and Human Fibroblasts" (abbreviated "Generation") in Nature. In "Generation," the authors point to dedifferentiation of somatic cells as an avenue for generating pluripotent stem cells useful for treating specific patients and diseases.

Format: Articles

Subject: Publications, Experiments

"Programmed Cell Death-II. Endocrine Potentiation of the Breakdown of the Intersegmental Muscles of Silkmoths" (1964), by Richard A. Lockshin and Carroll M. Williams

Richard A. Lockshin's 1963 PhD dissertation on cell death in insect metamorphosis was conducted under the supervision of Harvard insect physiologist Carroll M. Williams. Lockshin and Williams used this doctoral research as the basis for five articles, with the main title "Programmed Cell Death," that were published between 1964 and 1965 in the Journal of Insect Physiology. These articles examine the cytological processes, neuronal and endocrinal controls, and the influence of drugs on the mechanism of cell death observed in pupal muscle structures of the American silkmoth.

Format: Articles

Subject: Experiments, Publications

"Presence of Fetal DNA in Maternal Plasma and Serum" (1997), by Dennis Lo, et al.

In the late 1990s researchers Yuk Ming Dennis Lo and his colleagues isolated fetal DNA extracted from pregnant woman’s blood. The technique enabled for more efficient and less invasive diagnoses of genetic abnormalities in fetuses, such as having too many copies of chromosomes.

Format: Articles

Subject: Experiments

Barbara McClintock's Transposon Experiments in Maize (1931–1951)

Barbara McClintock conducted experiments on corn (Zea mays) in the United States in the mid-twentieth century to study the structure and function of the chromosomes in the cells. McClintock researched how genes combined in corn and proposed mechanisms for how those interactions are regulated. McClintock received the Nobel Prize in Physiology or Medicine in 1983, the first woman to win the prize without sharing it. McClintock won the award for her introduction of the concept of transposons, also called jumping genes.

Format: Articles

Subject: Experiments