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91.
Exploring the linkage between cell culture process parameters and downstream processing utilizing a plackett‐burman design for a model monoclonal antibody 下载免费PDF全文
Cyrus D. Agarabi Brittany K. Chavez Scott C. Lute Erik K. Read Sarah Rogstad David Awotwe‐Otoo Matthew R. Brown Michael T. Boyne II Kurt A. Brorson 《Biotechnology progress》2017,33(1):163-170
Linkage of upstream cell culture with downstream processing and purification is an aspect of Quality by Design crucial for efficient and consistent production of high quality biopharmaceutical proteins. In a previous Plackett‐Burman screening study of parallel bioreactor cultures we evaluated main effects of 11 process variables, such as agitation, sparge rate, feeding regimens, dissolved oxygen set point, inoculation density, supplement addition, temperature, and pH shifts. In this follow‐up study, we observed linkages between cell culture process parameters and downstream capture chromatography performance and subsequent antibody attributes. In depth analysis of the capture chromatography purification of harvested cell culture fluid yielded significant effects of upstream process parameters on host cell protein abundance and behavior. A variety of methods were used to characterize the antibody both after purification and buffer formulation. This analysis provided insight in to the significant impacts of upstream process parameters on aggregate formation, impurities, and protein structure. This report highlights the utility of linkage studies in identifying how changes in upstream parameters can impact downstream critical quality attributes. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:163–170, 2017 相似文献
92.
Brittany D. Kammerer Dietmar Kültz 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2009,179(4):535-542
The time-course of programmed cell death (apoptosis) during reorganization of gill epithelium in salinity-stressed tilapia
was analyzed using a recently developed method based on laser scanning cytometry (LSC) of dissociated gill cells. Apoptosis
in mitochondria-rich cells (MRC) was distinguished from that in other cell types using Na+/K+ ATPase (NKA) as a cell-specific marker. Caspase 3/7 activity in MRC, assessed using LSC and microplate assays, increased
significantly starting at 6 h of salinity stress and remained elevated for at least 5 days. This time-course of apoptosis
in MRC during acute salinity stress was reflected in elevated apoptotic DNA fragmentation. In parallel to induction of apoptosis,
MRC showed a pronounced shift to G2 phase of the cell cycle, which is indicative of G2/M cell cycle arrest, and an increase
in NKA abundance per MRC. Unlike in MRC, apoptosis was not significantly increased in other gill cell types, although there
was a small transient increase in DNA fragmentation at 6 h. G2 arrest was also observed. Overall, we interpret our data as
evidence for a significant role of apoptosis in the extensive reorganization of MRC populations that takes place during salinity
acclimation, perhaps similar to its well-established role during organismal development. 相似文献
93.
Rehan M. Baqri Brittany A. Turner Mary B. Rheuben Bradley D. Hammond Laurie S. Kaguni Kyle E. Miller 《PloS one》2009,4(11)
Mutations in mitochondrial DNA polymerase (pol γ) cause several progressive human diseases including Parkinson''s disease, Alper''s syndrome, and progressive external ophthalmoplegia. At the cellular level, disruption of pol γ leads to depletion of mtDNA, disrupts the mitochondrial respiratory chain, and increases susceptibility to oxidative stress. Although recent studies have intensified focus on the role of mtDNA in neuronal diseases, the changes that take place in mitochondrial biogenesis and mitochondrial axonal transport when mtDNA replication is disrupted are unknown. Using high-speed confocal microscopy, electron microscopy and biochemical approaches, we report that mutations in pol γ deplete mtDNA levels and lead to an increase in mitochondrial density in Drosophila proximal nerves and muscles, without a noticeable increase in mitochondrial fragmentation. Furthermore, there is a rise in flux of bidirectional mitochondrial axonal transport, albeit with slower kinesin-based anterograde transport. In contrast, flux of synaptic vesicle precursors was modestly decreased in pol γ−α mutants. Our data indicate that disruption of mtDNA replication does not hinder mitochondrial biogenesis, increases mitochondrial axonal transport, and raises the question of whether high levels of circulating mtDNA-deficient mitochondria are beneficial or deleterious in mtDNA diseases. 相似文献
94.
Göker M Held B Lapidus A Nolan M Spring S Yasawong M Lucas S Glavina Del Rio T Tice H Cheng JF Goodwin L Tapia R Pitluck S Liolios K Ivanova N Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Brambilla E Land M Hauser L Chang YJ Jeffries CD Brettin T Detter JC Han C Rohde M Sikorski J Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2010,3(1):66-75
Ignisphaera aggregans Niederberger et al. 2006 is the type and sole species of genus Ignisphaera. This archaeal species is characterized by a coccoid-shape and is strictly anaerobic, moderately acidophilic, heterotrophic hyperthermophilic and fermentative. The type strain AQ1.S1(T) was isolated from a near neutral, boiling spring in Kuirau Park, Rotorua, New Zealand. This is the first completed genome sequence of the genus Ignisphaera and the fifth genome (fourth type strain) sequence in the family Desulfurococcaceae. The 1,875,953 bp long genome with its 2,009 protein-coding and 52 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
95.
Mavromatis K Abt B Brambilla E Lapidus A Copeland A Deshpande S Nolan M Lucas S Tice H Cheng JF Han C Detter JC Woyke T Goodwin L Pitluck S Held B Brettin T Tapia R Ivanova N Mikhailova N Pati A Liolios K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Rohde M Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2010,2(3):290-299
Coraliomargarita akajimensis Yoon et al. 2007 is the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium that was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis is of special interest because of its phylogenetic position in a genomically under-studied area of the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
96.
Brittany Harker Martin 《Arts Education Policy Review》2017,118(2):116-122
The arts can be used to teach, not just as activities that enhance learning, but also as the primary medium through which students process, acquire, and represent knowledge. This means the arts can function as a language. If we accept this metaphor, and we truly want students to be fluent in the artistic languages, then the arts can be taught in the same constructive, sequential way language is taught, where the rules of the system are explicitly learned and fluency is acquired through regular application within a meaningful context. This article provides a framework for the implementation of effective arts integration in line with second language learning: Arts as a Second Language. In doing so, it addresses two common problems in arts education: when arts integration is disconnected from artistic development, and when discipline-based arts education is disconnected from other learning. Nine principles for teaching with an Arts as a Second Language policy are proposed. Ultimately, it is a call for pedagogical reform that enables equitable access for all students to learn in, about, and through the arts with school-wide policy that scaffolds artistic learning across the grades, embedded in meaningful contexts. 相似文献
97.
Sergio E. Bermúdez Brittany A. Armstrong Lillian Domínguez Aparna Krishnavajhala Alexander R. Kneubehl Sarah M. Gunter Adam Replogle Jeannine M. Petersen Job E. Lopez 《PLoS neglected tropical diseases》2021,15(8)
Tick-borne relapsing fever (TBRF) spirochetes are likely an overlooked cause of disease in Latin America. In Panama, the pathogens were first reported to cause human disease in the early 1900s. Recent collections of Ornithodoros puertoricensis from human dwellings in Panama prompted our interest to determine whether spirochetes still circulate in the country. Ornithodoros puertoricensis ticks were collected at field sites around the City of Panama. In the laboratory, the ticks were determined to be infected with TBRF spirochetes by transmission to mice, and we report the laboratory isolation and genetic characterization of a species of TBRF spirochete from Panama. Since this was the first isolation of a species of TBRF spirochete from Central America, we propose to designate the bacteria as Borrelia puertoricensis sp. nov. This is consistent with TBRF spirochete species nomenclature from North America that are designated after their tick vector. These findings warrant further investigations to assess the threat B. puertoricensis sp. nov. may impose on human health. 相似文献
98.
99.
Unstructured proteins, RNA or DNA components provide functionally important flexibility that is key to many macromolecular assemblies throughout cell biology. As objective, quantitative experimental measures of flexibility and disorder in solution are limited, small angle scattering (SAS), and in particular small angle X-ray scattering (SAXS), provides a critical technology to assess macromolecular flexibility as well as shape and assembly. Here, we consider the Porod-Debye law as a powerful tool for detecting biopolymer flexibility in SAS experiments. We show that the Porod-Debye region fundamentally describes the nature of the scattering intensity decay by capturing the information needed for distinguishing between folded and flexible particles. Particularly for comparative SAS experiments, application of the law, as described here, can distinguish between discrete conformational changes and localized flexibility relevant to molecular recognition and interaction networks. This approach aids insightful analyses of fully and partly flexible macromolecules that is more robust and conclusive than traditional Kratky analyses. Furthermore, we demonstrate for prototypic SAXS data that the ability to calculate particle density by the Porod-Debye criteria, as shown here, provides an objective quality assurance parameter that may prove of general use for SAXS modeling and validation. 相似文献
100.
Thomas A. Coudron Kent S. Shelby Mark R. Ellersieck Brittany R. Winston Holly J.R. Popham 《Entomologia Experimentalis et Applicata》2011,139(3):235-241
We report here the effects of a range of ascorbic acid concentrations (0.07, 0.3, 3.0, and 30.0 g l?1) in artificial diets on growth rates, adult weights, fecundity, and survival over two generations of the predatory stink bug, Podisus maculiventris (Say) (Heteroptera: Pentatomidae). Overall, a dietary level of 3.0 g l?1 gave the shortest developmental times over two generations. The likelihood of egg hatch at one ascorbic acid concentration compared to another concentration suggested that egg hatch increased as the concentration of ascorbic acid increased from 0.07 to 3.0 g l?1 and then declined from 3.0 to 30.0 g l?1. The combination of the maximum egg oviposition at 0.3 and 3.0 g l?1, egg hatch at 3.0 g l?1, and survival at 0.07 and 0.3 g l?1 suggests an overall superior performance at a concentration between 0.3 and 3.0 g l?1. Depletion of ascorbic acid below 3.0 g l?1 or addition of ascorbic acid above 3.0 g l?1 lowered the likelihood of egg hatch, which became more pronounced in the second generation. This is consistent with previously published information for phytophagous insects. 相似文献