The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform
J E Seegmiller - One of the best experts on this subject based on the ideXlab platform.
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detection of lesch nyhan syndrome carriers analysis of hair roots for hprt by agarose gel electrophoresis and Autoradiography
Clinical Genetics, 2008Co-Authors: Bohdan Bakay, Charmaine Tuckerpian, J E SeegmillerAbstract:Flat agarose gel electrophoresis and Autoradiography were used to analyze HPRT and APRT activity in individual hair roots collected from the scalps of females to determine the presence of HPRT-deficient cells. Autoradiographs of hair-root lysates of normal homozygous females contained two well-separated dark zones representing HPRT and APRT activities. In contrast, some hair roots from carriers of HPRT deficiency contained two zones of activity with the same relative proportion of APRT and HPRT as hair roots of normal homozygotes, while others contained decreased amounts of HPRT activity. These hair roots consisted of HPRT+ and HPRT- cells. In addition, some hair roots from heterozygous carriers contained APRT but no HPRT activity. Such hair roots consisted of HPRT- cells only.
Eric G. Solon - One of the best experts on this subject based on the ideXlab platform.
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Chapter 6:Autoradiography in Pharmaceutical Discovery and Development
Drug Discovery, 2011Co-Authors: Eric G. SolonAbstract:Autoradiography (ARG) is a powerful, high resolution, quantitative molecular imaging technique used to study the tissue distribution and pharmacokinetics of new radiolabeled chemical entities in biological models. In the classic technique, the radioactivity in a sample produces an image on a detection media such as X-ray film, or another type of media that contains a photographic emulsion. In most cases the specimen contains a compound that had been intentionally labeled with an isotope having low energy beta radioactivity and that is synthesized into the molecule without damaging its chemical characteristics and/or intended effect(s). Most often the isotope is 14Carbon, 3Hydrogen, or 125Iodine, however, 35Sulfur, 33Phosphorus, and other beta emitters can and have been used. In pharmaceutical research, the specimens can be single cells, individual organs, organ systems, and/or the whole-body of lab animals, such as rats, mice, rabbits, dogs, and monkeys. ARG can be separated into two basic categories: macro-Autoradiography and micro-Autoradiography. Macro-Autoradiography is imaging of thin sections obtained from intact organs, organ systems, and/or intact whole-bodies, and micro-Autoradiography provides localization of radioactivity at the cellular level in a histological preparation. Whole-body Autoradiography (WBA) is a general term given to a macro-Autoradiography technique where a radioactive compound, which is administered to a lab animal, is visualized by obtaining autoradiographs from thin whole-body sections, which have been obtained from the intact frozen carcass of a lab animal. Micro-Autoradiography results are obtained from much thinner cryosections obtained form individual tissues that have been dissected out from an animal and that have been exposed to photographic emulsion on a glass slide, which is used for typical light microscopy. The roles of WBA and MARG in drug discovery and development have changed over the years, and the use of WBA has increased dramatically due to the development of phosphor imaging technology. This chapter will discuss the history, validation, current applications, instrumentation, and, strengths and limitations of WBA and MARG in pharmaceutical discovery and development. It will also present some ideas on how these techniques might be improved in the future to better serve pharmaceutical research.
Jean-jacques Dreifuss - One of the best experts on this subject based on the ideXlab platform.
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Oxytocin Excites Neurons Located in the Ventromedial Nucleus of the Guinea‐Pig Hypothalamus
Journal of neuroendocrinology, 1991Co-Authors: Kiyotoshi Inenaga, H. Karman, Hiroshi Yamashita, Eliane Tribollet, Mario Raggenbass, Jean-jacques DreifussAbstract:Abstract The area of the ventromedial nucleus of the hypothalamus in the guinea-pig was shown in autoradiographs to contain high affinity binding sites for oxytocin. In order to ascertain whether these sites may represent neuronal receptors, single-cell extracellular recordings were obtained from ventromedial neurons in coronal slices of the hypothalamus of adult guinea-pigs. Oxytocin applied in the nanomolar range excited about half of the neurons tested; none were inhibited. The response to the peptide was reversible and concentration-dependent. It was exerted directly since it persisted under the condition of synaptic isolation. Moreover, the effect was specific since it could be mimicked by a selective oxytocin agonist and since vasopressin was usually at least 10-fold weaker than oxytocin. These findings suggest that the binding sites for oxytocin detected by light microscopic Autoradiography in the guinea-pig hypothalamic ventromedial nucleus represent functional receptors.
Bohdan Bakay - One of the best experts on this subject based on the ideXlab platform.
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detection of lesch nyhan syndrome carriers analysis of hair roots for hprt by agarose gel electrophoresis and Autoradiography
Clinical Genetics, 2008Co-Authors: Bohdan Bakay, Charmaine Tuckerpian, J E SeegmillerAbstract:Flat agarose gel electrophoresis and Autoradiography were used to analyze HPRT and APRT activity in individual hair roots collected from the scalps of females to determine the presence of HPRT-deficient cells. Autoradiographs of hair-root lysates of normal homozygous females contained two well-separated dark zones representing HPRT and APRT activities. In contrast, some hair roots from carriers of HPRT deficiency contained two zones of activity with the same relative proportion of APRT and HPRT as hair roots of normal homozygotes, while others contained decreased amounts of HPRT activity. These hair roots consisted of HPRT+ and HPRT- cells. In addition, some hair roots from heterozygous carriers contained APRT but no HPRT activity. Such hair roots consisted of HPRT- cells only.
J. R. Russell - One of the best experts on this subject based on the ideXlab platform.
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High resolution scanning of DNA autoradiographs.
Electrophoresis, 1991Co-Authors: J. R. RussellAbstract:The sizes of DNA fragments (alleles) on autoradiographs are measured by means of a computerised video scanner developed in this laboratory. This report investigates the advantages of using higher resolution equipment for this purpose. High resolution is simulated by using existing equipment and moving the video camera closer to the autoradiograph. Test autoradiographs, used to validate the original scanner, have been rescanned to determine the degree of improvement that could be obtained using expensive high resolution equipment.