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T. R. Davis T. J. Wickham K. A. McKenna R. R. Granados M. L. Shuler H. A. Wood 《In vitro cellular & developmental biology. Animal》1993,29(5):388-390
Summary A recombinantAutographa californica baculovirus expressing secreted alkaline phosphatase (SEAP) gene was used to evaluate the expression of a secreted glycoprotein
in eight insect cell lines derived fromSpodoptera frugiperda, Trichoplusia ni, Mamestra brassicae andEstigmene acrea. Because cell density was found to influence protein production, SEAP production was evaluated at optimal cell densities
for each cell line on both a per cell and per milliliter basis. On a per cell basis, theT. ni-derived BTI-TN-5B1-4 cells produced a minimum of 20-fold more SEAP than theS. frugiperda-derived Sf9 or Sf21 cell lines and a minimum of 9-fold more than any of the other cell lines growing in serum-containing
medium. On a per milliliter basis, BTI-TN-5B1-4 cells produced a minimum of fivefold more SEAP than any of the other cell
lines tested. Using cell lines that were adapted to serum-free medium, SEAP yields were the same or better than their counterparts
in serum-containing medium. At 3 days postinoculation, extracellular SEAP activity ranged from 59 to 85% of total SEAP activity
with cell lines grown in serum-free and serum-containing media. 相似文献
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F. Andrew Ray Erin Robinson Miles McKenna Megumi Hada Kerry George Francis Cucinotta Edwin H. Goodwin Joel S. Bedford Susan M. Bailey Michael N. Cornforth 《Radiation and environmental biophysics》2014,53(2):255-263
Chromosome aberrations in blood lymphocytes provide a useful measure of past exposure to ionizing radiation. Despite the widespread and successful use of the dicentric assay for retrospective biodosimetry, the approach suffers substantial drawbacks, including the fact that dicentrics in circulating blood have a rather short half-life (roughly 1–2 years by most estimates). So-called symmetrical aberrations such as translocations are far more stable in that regard, but their high background frequency, which increases with age, also makes them less than ideal for biodosimetry. We developed a cytogenetic assay for potential use in retrospective biodosimetry that is based on the detection of chromosomal inversions, another symmetrical aberration whose transmissibility (stability) is also ostensibly high. Many of the well-known difficulties associated with inversion detection were circumvented through the use of directional genomic hybridization, a method of molecular cytogenetics that is less labor intensive and better able to detect small chromosomal inversions than other currently available approaches. Here, we report the dose-dependent induction of inversions following exposure to radiations with vastly different ionization densities [i.e., linear energy transfer (LET)]. Our results show a dramatic dose-dependent difference in the yields of inversions induced by low-LET gamma rays, as compared to more damaging high-LET charged particles similar to those encountered in deep space. 相似文献
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Adam Joules Julianne Connors Rachel Johnson Elizabeth A. Van Orsow David H. McKenna Sarah Nikiforow Jerome Ritz Adrian Gee Allison Hubel 《Cytotherapy》2021,23(4):285-292
Background aimsCell therapies are an emerging treatment option for a variety of diseases, especially with the success of chimeric antigen receptor T-cell therapies. With 18 FDA-approved cell therapy products as of December 2020 and a growing number in clinical trials, standards for most aspects of the cell therapy lifecycle are well-established by professional organizations like AABB and FACT; however, there are limited standardized protocols regarding the day-of infusion.MethodsInfusions were observed at three academic medical centers in the United States, and the workflows were analyzed and compared based on factors including facility layout, product verification processes, cryobag design, timing restrictions, and use of electronic medical records.ResultsVariations between the facilities were identified with product thawing location and cell therapy lab location being the most important factors in time from thaw to infusion.ConclusionsBased on this analysis, opportunities were identified for standardization and streamlining the infusion workflow which may help facilitate adoption of new and existing cell therapies at a wider range of hospitals. 相似文献
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Richard Gawne Kenneth Z. McKenna H. Frederik Nijhout 《BioEssays : news and reviews in molecular, cellular and developmental biology》2018,40(1)
The question of whether the modern evolutionary synthesis requires an extension has recently become a topic of discussion, and a source of controversy. We suggest that this debate is, for the most part, not about the modern synthesis at all. Rather, it is about the extent to which genetic mechanisms can be regarded as the primary determinants of phenotypic characters. The modern synthesis has been associated with the idea that phenotypes are the result of gene products, while supporters of the extended synthesis have suggested that environmental factors, along with processes such as epigenetic inheritance, and niche construction play an important role in character formation. We argue that the methodology of the modern evolutionary synthesis has been enormously successful, but does not provide an accurate characterization of the origin of phenotypes. For its part, the extended synthesis has yet to be transformed into a testable theory, and accordingly, has yielded few results. We conclude by suggesting that the origin of phenotypes can only be understood by integrating findings from all levels of the organismal hierarchy. In most cases, parts and processes from a single level fail to accurately explain the presence of a given phenotypic trait. 相似文献
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