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"Further Experiments on Artificial Parthenogenesis and the Nature of the Process of Fertilization" (1900), by Jacques Loeb

Jacques Loeb broadened and corrected his earlier claims concerning artificial parthenogenesis in sea urchins in a series of experiments in 1900. He published these findings, "Further Experiments on Artificial Parthenogenesis and the Nature of The Process of Fertilization," in a 1900 issue of The American Journal of Physiology.

Format: Articles

Subject: Experiments

"Experiments in Plant Hybridization" (1866), by Johann Gregor Mendel

During the mid-nineteenth century, Johann Gregor Mendel experimented with pea plants to develop a theory of inheritance. In 1843, while a monk in the Augustian St Thomas's Abbey in Brünn, Austria, now Brno, Czech Repubic, Mendel examined the physical appearance of the abbey's pea plants (Pisum sativum) and noted inconsistencies between what he saw and what the blending theory of inheritance, a primary model of inheritance at the time, predicted.

Format: Articles

Subject: Experiments

"Experiments on Artificial Parthenogenesis in Annelids (Chaetopterus) and the Nature of the Process of Fertilization" (1901), by Jacques Loeb

Jacques Loeb showed that scientists could achieve artificial parthenogenesis with some types of annelid worm eggs through a series of experiments in 1900. Loeb published the results of his experiments in 1901 as "Experiments on Artificial Parthenogenesis in Annelids (Chaetopterus) and the Nature of the Process of Fertilization," in The American Journal of Physiology. Loeb 's results broadened the range of animals to which artificial parthenogenesis applied beyond sea urchins.

Format: Articles

Subject: Experiments

"On the Nature of the Process of Fertilization and the Artificial Production of Normal Larvae (Plutei) From the Unfertilized Eggs of the Sea Urchin" (1899), by Jacques Loeb

Jacques Loeb developed procedures to make embryos from unfertilized sea urchin eggs in 1899. Loeb called the procedures "artificial parthenogenesis," and he introduced them and his results in "On the Nature of the Process of Fertilization and the Artificial Production of Norma Larvae (Plutei) from the Unfertilized Eggs of the Sea Urchin" in an 1899 issue of The American Journal of Physiology. In 1900 Loeb elaborated on his experiments.

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

"Selective Growth Stimulating Effects of Mouse Sarcoma on the Sensory and Sympathetic Nervous System of the Chick Embryo" (1951), by Rita Levi-Montalcini and Viktor Hamburger

In "Selective Growth Stimulating Effects of Mouse Sarcoma on the Sensory and Sympathetic Nervous System of the Chick Embryo," Rita Levi-Montalcini and Viktor Hamburger explored the effects of two nerve growth stimulating tumors; mouse sarcomas 180 and 37. This experiment led to the discovery that nerve growth factor was a diffusible chemical and later to discoveries that the compound was a protein. Although this paper was an important step in the discovery of nerve growth factor, the term "nerve growth factor" was not used in this paper.

Format: Articles

Subject: Experiments

"Development, Plasticity and Evolution of Butterfly Eyespot Patterns" (1996), by Paul M. Brakefield et al.

Paul M. Brakefield and his research team in Leiden, the Netherlands, examined the development, plasticity, and evolution of butterfly eyespot patterns, and published their findings in Nature in 1996. Eyespots are eye-shaped color patterns that appear on the wings of some butterflies and birds as well as on the skin of some fish and reptiles. In butterflies, such as the peacock butterfly Aglais, the eyespots resemble the eyes of birds and help butterflies deter potential predators.

Format: Articles

Subject: Experiments

"Interspecific Chimeras in Mammals: Successful Production of Live Chimeras Between Mus musculus and Mus caroli" (1980), by Janet Rossant and William I. Frels

In 1980 Janet Rossant and William I. Frels published their paper, "Interspecific Chimeras in Mammals: Successful Production of Live Chimeras Between Mus musculus and Mus caroli," in Science. Their experiment involved the first successful creation of interspecific mammalian chimeras. Mammalian chimeras are valuable for studying early embryonic development. However, in earlier studies, clonal analysis was restricted by the lack of a cell marker, present at all times, that makes a distinction between the two parental cell types in situ.

Format: Articles

Subject: Experiments

"Experimental Chimeras' Removal of Reproductive Barrier Between Sheep and Goat" (1984), by Sabine Meinecke-Tillmann and Burkhard Meinecke

In 1984 Sabine Meinecke-Tillmann and Burkhard Meinecke published their article "Experimental Chimeras - Removal of Reproductive Barrier Between Sheep and Goat" in Nature. Their study conquered the reproductive barrier between sheep and goats through embryo manipulation. Their article appeared in Nature on the same day that a similar experiment, conducted by Carole Fehilly, Steen Willadsen, and Elizabeth Tucker was published regarding reproductive barriers between sheep and goats.

Format: Articles

Subject: Experiments

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

"Embryonic Stem Cell Lines Derived from Human Blastocytes" (1998), by James Thomson

After becoming chief pathologist at the University of Wisconsin-Madison Wisconsin Regional Primate Center in 1995, James A. Thomson began his pioneering work in deriving embryonic stem cells from isolated embryos. That same year, Thomson published his first paper, "Isolation of a Primate Embryonic Stem Cell Line," in Proceedings of the National Academy of Sciences of the United States of America, detailing the first derivation of primate embryonic stem cells. In the following years, Thomson and his team of scientists - Joseph Itskovitz-Eldor, Sander S. Shapiro, Michelle A.

Format: Articles

Subject: Experiments, Publications

"In vitro Experiments on the Effects of Mouse Sarcomas 180 and 37 on the Spinal and Sympathetic Ganglia of the Chick Embryo" (1954), by Rita Levi-Montalcini, Viktor Hamburger, and Hertha Meyer

"In vitro Experiments on the Effects of Mouse Sarcomas 180 and 37 on the Spinal and Sympathetic Ganglia of the Chick Embryo" were experiments conducted by Rita Levi-Montalcini in conjunction with Viktor Hamburger and Hertha Meyer and published in Cancer Research in 1954. In this series of experiments, conducted at the University of Brazil, Levi-Montalcini demonstrated increased nerve growth by introducing specific tumors (sarcomas) to chick ganglia. Ganglia are clusters of nerve cells, from which nerve fibers emerge.

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

Paul Kammerer's Experiments on the Midwife Toad (1905-1910)

In the first decade of the twentieth century, Paul Kammerer, a zoologist working at the Vivarium in Vienna, Austria, conducted research on developmental mechanisms, including a series of breeding experiments on toads (Alytes obstetricans). Kammerer claimed that his results demonstrated that organisms could transmit acquired characteristics to their offspring.

Format: Articles

Subject: Experiments

"Developmental Capacity of Nuclei Transplanted from Keratinized Skin Cells of Adult Frogs" (1975), by John Gurdon, Ronald Laskey, and O. Raymond Reeves

In 1975 John Gurdon, Ronald Laskey, and O. Raymond Reeves published "Developmental Capacity of Nuclei Transplanted from Keratinized Skin Cells of Adult Frogs," in the Journal of Embryology and Experimental Morphology. Their article was the capstone of a series of experiments performed by Gurdon during his time at Oxford and Cambridge, using the frog species Xenopus laevis. Gurdon's first experiment in 1958 showed that the nuclei of Xenopus cells maintained their ability to direct normal development when transplanted.

Format: Articles

Subject: Experiments, Publications

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

"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

The Effects of Gene Regulation on Aging in Caenorhabditis elegans (2003)

In 2003, molecular biology and genetics researchers Coleen T. Murphy, Steven A. McCarroll, Cornelia I. Bargmann, Andrew Fraser, Ravi S. Kamath, Julie Ahringer, Hao Li, and Cynthia Kenyon conducted an experiment that investigated the cellular aging in, Caenorhabditis elegans (C. elegans) nematodes. The researchers investigated the interactions between the transcription factor DAF-16 and the genes that regulate the production of an insulin-like growth factor 1 (IGF-1-like) protein related to the development, reproduction, and aging in C. elegans.

Format: Articles

Subject: Experiments

A plant genetically modified that accumulates Pb is especially promising for phytoremediation (2003), by Carmina Gisbert et al.

In 2003, Carmina Gisbert and her research team produced a tobacco plant that could remove lead from soil. To do so, they inserted a gene from wheat plants that produces phytochelatin synthase into a shrub tobacco plant (Nicotiana glauca) to increase N. glauca's absorption and tolerance of toxic metals, particularly lead and cadmium. Gisbert and her team aimed to genetically modify a plant so that it could be used for phytoremediation- using plants to remove toxic substances from the soil.

Format: Articles

Subject: Experiments, Technologies

Paul Kammerer's Experiments on Sea-squirts in the Early Twentieth Century

In the early twentieth century, Paul Kammerer, a zoologist working at the Vivarium in Vienna, Austria, experimented on sea-squirts (Ciona intestinalis). Kammerer claimed that results from his experiments demonstrated that organisms could transmit characteristics that they had acquired in their lifetimes to their offspring. Kammerer conducted breeding experiments on sea-squirts and other organisms at a time when Charles Darwin's 1859 theory of evolution lacked evidence to explain how offspring inherited traits from their parents.

Format: Articles

Subject: Experiments, Organisms

"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

Edgar Allen and Edward A. Doisy's Extraction of Estrogen from Ovarian Follicles, (1923)

In the early 1920s, researchers Edgar Allen and Edward Adelbert Doisy conducted an experiment that demonstrated that ovarian follicles, which produce eggs in mammals, also contain and produce what they called the primary ovarian hormone, later renamed estrogen. In their experiment, Doisy and Allen extracted estrogen from the ovarian follicles of hogs and proved that they had isolated estrogen by using a measurement later renamed the Allen-Doisy test.

Format: Articles

Subject: Experiments

"Sheep Cloned by Nuclear Transfer from a Cultured Cell Line" (1996), by Keith Campbell, Jim McWhir, William Ritchie, and Ian Wilmut

In 1995 and 1996, researchers at the Roslin Institute in Edinburgh, Scotland, cloned mammals for the first time. Keith Campbell, Jim McWhir, William Ritchie, and Ian Wilmut cloned two sheep, Megan and Morag, using sheep embryo cells. The experiments indicated how to reprogram nuclei from differentiated cells to produce live offspring, and that a single population of differentiated cells could produce multiple offspring. They reported their results in the article 'Sheep Cloned by Nuclear Transfer from a Cultured Cell Line' in March 1996.

Format: Articles

Subject: Experiments

Paul Kammerer's Experiments on Salamanders (1903-1912)

In the early twentieth century, Paul Kammerer conducted a series of experiments to demonstrate that organisms could transmit characteristics acquired in their lifetimes to their offspring. In his 1809 publication, zoologist Jean-Baptiste Lamarck had hypothesized that living beings can inherit features their parents or ancestors acquired throughout life. By breeding salamanders, as well as frogs and other organisms, Kammerer tested Lamarck's hypothesis in an attempt to provide evidence for Lamarck's theory of the inheritance of acquired characteristics.

Format: Articles

Subject: Experiments

Viktor Hamburger's Study of Central-Peripheral Relations in the Development of Nervous System

An important question throughout the history of embryology is whether the formation of a biological structure is predetermined or shaped by its environment. If both intrinsic and environmental controls occur, how exactly do the two processes coordinate in crafting specific forms and functions? When Viktor Hamburger started his PhD study in embryology in the 1920s, few neuroembryologists were investigating how the central neurons innervate peripheral organs.

Format: Articles

Subject: Experiments

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