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Displaying 51 - 75 of 85 items.

Cerebral Organoid as a Model System in the Study of Microcephaly

Scientists use cerebral organoids, which are artificially produced miniature organs that represent embryonic or fetal brains and have many properties similar to them, to help them study developmental disorders like microcephaly. In human embryos, cerebral tissue in the form of neuroectoderm appears within the first nine weeks of human development, and it gives rise to the brain and spinal cord.

Format: Articles

Subject: Technologies

Ooplasmic Transfer Technology

Ooplasmic transfer, also called cytoplasmic transfer, is an outside the body, in vitro fertilization (IVF) technique. Ooplasmic transfer in humans (Homo sapiens) is similar to in vitro fertilization (IVF), with a few additions. IVF is the process in which doctors manually combine an egg and sperm cells in a laboratory dish, as opposed to artificial insemination, which takes place in the female's body. For ooplasmic transfer, doctors withdraw cytoplasm from a donor's oocyte, and then they inject that cytoplasm with sperm into a patient's oocyte.

Format: Articles

Subject: Technologies

Light Therapy for Neonatal Jaundice

Light therapy, also called phototherapy, exposes infants with jaundice, a yellowing of the skin and eyes, to artificial or natural light to break down the buildup of bilirubin pigment in the blood. Bilirubin is an orange to red pigment produced when red blood cells break down, which causes infants to turn into a yellowish color. Small amounts of bilirubin in the blood are normal, but when there is an accumulation of excess bilirubin pigment, the body deposits the excess bilirubin in the layer of fat beneath the skin.

Format: Articles

Subject: Technologies

Ericsson Method of Sperm Separation

In 1973, Ronald Ericsson developed the Ericsson method, which is a technique used to separate human male sperm cells by their genetic material. Ericsson, a physician and reproduction researcher, developed the method while conducting research on sperm isolation in Berlin, Germany, in the early 1970s. He found that the sperm cells that carry male-producing Y chromosomes move through liquid faster than the cells that carry female-producing X chromosomes.

Format: Articles

Subject: Technologies

Beadle and Ephrussi’s Technique to Transplant Optic Discs between Fruit Fly Larvae

In 1935, George Beadle and Boris Ephrussi developed a technique to transplant optic discs between fruit fly larvae. They developed it while at the California Institute of Technology in Pasedena, California. Optic discs are tissues from which the adult eyes develop. Beadle and Ephrussi used their technique to study the development of the eye and eye pigment. (1) The experimenter dissects a donor larva, which is in the third instar stage of development, and removes the optic disc (colored red) with a micropipette.

Format: Graphics

Subject: Technologies, Experiments, Organisms

Beadle and Ephrussi's Transplantation Technique for Drosophila

Boris Ephrussi and George Wells Beadle developed a transplantation technique on flies, Drosophila melanogaster, which they described in their 1936 article A Technique of Transplantation for Drosophila. The technique of injecting a tissue from one fly larva into another fly larva, using a micropipette, to grow that tissue in the second larvae, was a means for investigating development of Drosophila. Through this technique, Beadle and Ephrussi studied the role of genes in embryological processes.

Format: Articles

Subject: Technologies

Endoscopic Fetoscopy

Endoscopic fetoscopy is a minimally invasive surgical procedure performed during pregnancy that allows physicians to view the fetus in-utero. Physicians use endoscopic fetoscopy to evaluate, diagnose, and treat fetal abnormalities. Physicians use an endoscope, or a thin, flexible surgical device with a light attached to its end, to perform endoscopic fetoscopy procedures. In 1954, Björn Westin performed the first endoscopic fetoscopy in Sweden.

Format: Articles

Subject: Technologies

Cervarix HPV Vaccination Series

In 2011, United Kingdom pharmaceutical company GlaxoSmithKline released Cervarix, a vaccination series protecting girls and women from two strains of Human Papillomavirus, or HPV. HPV, a sexually transmitted infection, can present in men and women without symptoms, or may cause symptoms such as genital warts. There is a link between HPV and cervical, vaginal, anal, head, neck, and face cancers, and Cervarix can reduce genital cancers in girls and women, particularly cervical cancer.

Format: Articles

Subject: Technologies

HeLa Cell Line

The HeLa cell line was the first immortal human cell line that George Otto Gey, Margaret Gey, and Mary Kucibek first isolated from Henrietta Lacks and developed at The Johns Hopkins Hospital in Baltimore, Maryland, in 1951. An immortal human cell line is a cluster of cells that continuously multiply on their own outside of the human from which they originated. Scientists use immortal human cell lines in their research to investigate how cells function in humans.

Format: Articles

Subject: Technologies, Experiments, People, Ethics

Radioimmunoassay

Radioimmunoassay (RIA) is a technique in which researchers use radioactive isotopes as traceable tags to quantify specific biochemical substances from blood samples. Rosalyn Yalow and Solomon Berson developed the method in the 1950s while working at the Bronx Veterans Administration (VA) Hospital in New York City, New York. RIA requires small samples of blood, yet it is extremely sensitive to minute quantities of biological molecules within the sample. The use of RIA improved the accuracy of many kinds of medical diagnoses, and it influenced hormone and immune research around the world.

Format: Articles

Subject: Technologies

Equilibrium Density Gradient Centrifugation in Cesium Chloride Solutions Developed by Matthew Meselson and Franklin Stahl

Matthew Meselson, Franklin Stahl, and Jerome Vinograd, developed cesium chloride, or CsCl, density gradient centrifugation in the 1950s at the California Institute of Technology, or Caltech, in Pasadena, California. Density gradient centrifugation enables scientists to separate substances based on size, shape, and density. Meselson and Stahl invented a specific type of density gradient centrifugation, called isopycnic centrifugation that used a solution of cesium chloride to separate DNA molecules based on density alone.

Format: Articles

Subject: Technologies

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

Golgi Staining Technique

The Golgi staining technique, also called the black reaction after the stain's color, was developed in the 1870s and 1880s in Italy to make brain cells (neurons) visible under the microscope. Camillo Golgi developed the technique while working with nervous tissue, which required Golgi to examine cell structure under the microscope. Golgi improved upon existing methods of staining, enabling scientists to view entire neurons for the first time and changing the way people discussed the development and composition of the brain's cells.

Format: Articles

Subject: Technologies, Processes

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

ABO Blood Type Identification and Forensic Science (1900-1960)

The use of blood in forensic analysis is a method for identifying individuals suspected of committing some kinds of crimes. Paul Uhlenhuth and Karl Landsteiner, two scientists working separately in Germany in the early twentieth century, showed that there are differences in blood between individuals. Uhlenhuth developed a technique to identify the existence of antibodies, and Landsteiner and his students showed that humans had distinctly different blood types called A, B, AB, and O.

Format: Articles

Subject: Theories, Legal, Technologies

Magnetic Resonance Microscopy (MRM)

Magnetic Resonance Microscopy (MRM) is an imaging method that allows the visualization of internal body structures. Using powerful magnets to send energy into cells, MRM picks up signals from inside a specimen and translates them into detailed computer images. MRM is a useful tool for scientists because of its ability to generate digital slices of scanned specimens that can be constructed into virtual 3D images without destroying the specimens. MRM has become an increasingly prevalent imaging technique in embryological studies.

Format: Articles

Subject: Technologies

Copper Intrauterine Device (IUD)

The copper intrauterine device, or IUD, is a long-term, reversible contraceptive first introduced by Howard Tatum and Jamie Zipper in 1967. Health care providers place an IUD inside a woman’s uterus to prevent pregnancy. Copper IUDs are typically made of T-shaped plastic with some portion covered with exposed copper. Prior to the invention of the first IUDs, women had few long-term options for safe and reliable birth control. Those options mostly consisted of barrier methods and the oral birth control pill, which were only effective if used correctly and consistently.

Format: Articles

Subject: Technologies

Mammography

Mammography or mastography is an imaging technology used in the twentieth century for the detection of breast cancer and other breast abnormalities. Breast cancer is an abnormal growth in breast tissue that can spread to other parts of the body and cause death. Breast cancer affects about twelve percent of women worldwide. In the twenty-first century, mammography is one of the most accurate tools for screening and diagnosing breast cancer.

Format: Articles

Subject: Technologies

Warren Tay (1843–1927)

The arterial switch operation, also called the Jatene procedure, is an operation in which surgeons redirect the flow of blood through abnormal hearts. In 1975, Adib Jatene conducted the first successful arterial switch operation on a human infant. The arterial switch operation corrects a condition called transposition of the great arteries, abbreviated TGA, also called transposition of the great vessels, abbreviated TGV. TGA occurs when the pulmonary artery, which supplies deoxygenated blood to the lungs, and the aorta, which takes oxygenated blood to the body, are switched, or transposed.

Format: Articles

Subject: Technologies

Menstrual Tampon

Menstrual tampons are feminine hygiene devices, usually made of absorbent cotton, that are temporarily inserted into the vagina for absorbing a woman’s blood during menstruation. In 1931, Earl Haas invented the menstrual tampon most commonly used in the twenty-first century. Later, Gertrude Tendrich produced the first commercial tampon brand, Tampax, using Haas’s patented design. Tendrich and Haas’s tampon was made of tightly compacted absorbent cotton, shaped like a bullet, and had a string attached at the base that allowed for easy removal from the woman’s body.

Format: Articles

Subject: Technologies

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

Subject: Technologies

Hanging Drop Tissue Culture

The hanging drop tissue culture is a technique utilized in embryology and other fields to allow growth that would otherwise be restricted by the flat plane of culture dishes and also to minimize the surface area to volume ratio, slowing evaporation. The classic hanging drop culture is a small drop of liquid, such as plasma or some other media allowing tissue growth, suspended from an inverted watch glass. The hanging drop is then suspended by gravity and surface tension, rather than spreading across a plate.

Format: Articles

Subject: Technologies

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

Ethics and Induced Pluripotent Stem Cells

The recent development of induced pluripotent stem cells (iPSCs) and related technologies has caught the attention of scientists, activists, politicians, and ethicists alike. IPSCs gained immediate international attention for their apparent similarity to embryonic stem cells after their successful creation in 2006 by Shinya Yamanaka and in 2007 by James Thompson and others.

Format: Articles

Subject: Technologies, Ethics