CO2 in large-scale and high-density CHO cell perfusion culture

1996 ◽  
Vol 22 (1-3) ◽  
pp. 65-78 ◽  
Author(s):  
David R. Gray ◽  
Su Chen ◽  
William Howarth ◽  
Duane Inlow ◽  
Brian L. Maiorella
2003 ◽  
Vol 82 (7) ◽  
pp. 751-765 ◽  
Author(s):  
D. Voisard ◽  
F. Meuwly ◽  
P.-A. Ruffieux ◽  
G. Baer ◽  
A. Kadouri

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Menglin Shang ◽  
Taehong Kwon ◽  
Jean-Francois P. Hamel ◽  
Chwee Teck Lim ◽  
Bee Luan Khoo ◽  
...  

AbstractChinese hamster ovary (CHO) cells have been the most commonly used mammalian host for large-scale commercial production of therapeutic proteins, such as monoclonal antibodies. Enhancement of productivity of these CHO cells is one of the top priorities in the biopharmaceutical industry to reduce manufacturing cost. Although there are many different methods (e.g. temperature, pH, feed) to improve protein production in CHO cells, the role of physiologically relevant hydrostatic pressure in CHO cell culture has not been reported yet. In this study, four different hydrostatic pressures (0, 30, 60, and 90 mmHg) were applied to batch CHO cells, and their cell growth/metabolism and IgG1 production were examined. Our results indicate that hydrostatic pressure can increase the maximum cell concentration by up to 50%. Moreover, overall IgG1 concentration on Day 5 showed that 30 mmHg pressure can increase IgG1 production by 26%. The percentage of non-disulphide-linked antibody aggregates had no significant change under pressure. Besides, no significant difference was observed between 30 mmHg and no pressure conditions in terms of cell clumping formation. All these findings are important for the optimization of fed-batch or perfusion culture for directing cell growth and improving antibody production.


2018 ◽  
Vol 12 (12) ◽  
pp. 2266-2276
Author(s):  
Jing Liu ◽  
Chengpan Li ◽  
Shaohui Cheng ◽  
Shengnan Ya ◽  
Dayong Gao ◽  
...  

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3069
Author(s):  
Zheng Liu ◽  
Ling Lin ◽  
Haozhe Zhu ◽  
Zhongyuan Wu ◽  
Xi Ding ◽  
...  

Muscle stem cells (MuSCs) isolated ex vivo are essential original cells to produce cultured meat. Currently, one of the main obstacles for cultured meat production derives from the limited capacity of large-scale amplification of MuSCs, especially under high-density culture condition. Here, we show that at higher cell densities, proliferation and differentiation capacities of porcine MuSCs are impaired. We investigate the roles of Hippo-YAP signaling, which is important regulators in response to cell contact inhibition. Interestingly, abundant but not functional YAP proteins are accumulated in MuSCs seeded at high density. When treated with lysophosphatidic acid (LPA), the activator of YAP, porcine MuSCs exhibit increased proliferation and elevated differentiation potential compared with control cells. Moreover, constitutively active YAP with deactivated phosphorylation sites, but not intact YAP, promotes cell proliferation and stemness maintenance of MuSCs. Together, we reveal a potential molecular target that enables massive MuSCs expansion for large-scale cultured meat production under high-density condition.


2021 ◽  
Author(s):  
◽  
Yingyi Zhang

<p>Parametric tools have been broadly implemented in Architecture, Engineering and Construction (AEC) industry. Recently, an increasing volume of research finds that parametric tools also have the capability to facilitate large-scale planning and urban design. Much of this research, however, focuses on parametric representation or environment simulation. There is insufficient research about using parametric tools to enhance urban regulation. Parametric tools can provide smart design procedures by integrating strategies, solutions and expressions in one system. They may allow alternative approaches to urban regulation that conventional tools do not process.  This research aims to create a parametric modelling system to aid urban regulation. The system offers a visualised coding interface to manipulate parameters and achieve interactive performance feedback at the early stage of urban regulation. Form-Based Code uses the modelling system in this research. It generates a specific morphology by controlling physical form with less focus on land use. With the rise of New Urbanism, Form-Based Code has been used in various American regulation projects. This research extends the application of Form-Based Code, adopting it for urban-peripheral environments outside of the USA. High-density cities where provide the volumetric morphology context is important for this work. Tsim Sha Tsui area of Hong Kong works as an experimental site.  The feasibility of parametric urban regulation is examined by developing a parametric modelling system for Form-Based Code in Hong Kong. Understanding the site’s form characteristics, the transect matrix of Form-Based Code is expanded by incorporating multi-layered zone types and regulating plans. Embedding the zones into parametric modelling software Rhinoceros 3D and Grasshopper 3D, a regenerative prototype works to create real-time scenarios responding to parameters, rules and geometry constraints. The results of parametric urban regulation are evaluated by both Form-Based Code standards and local urban regulation standards to assess its feasibility in context.  This research demonstrates that the parametric modelling system for Form-Based Code has both technological and implemental potential to work as an alternative approach to urban regulation, especially in complex developments. Form complexity is a reflection of sophisticated human-society systems and the sequential evolution of a dynamic morphology. Form-Based Code is enhanced by the parametric modelling system to describe and regulate form complexity in a logical manner. Additionally, although parametric Form-Based Code processing is based on the original Form-Based Code, it is not limited to that. Describing urban regulation with visualised models bridges specialists and the public in community demonstrations and code assembling. The parametric modelling system has a positive impact on resolving challenges, predicting outcomes, and applying urban regulation innovation to the volumetric morphology of high-density cities in Asia.</p>


Author(s):  
Qinqing Kang

Node self-positioning is one of the supporting technologies for wireless sensor network applications. In this paper, a clustering localization algorithm is proposed for large-scale high-density wireless sensor networks. Firstly, the potential of the node is defined as the basis for the election of the cluster head. The distance between the nodes in the network is calculated indirectly by the relationship between the received signal strength and the communication radius. The topology information in each cluster is saved by the cluster head, and the linear programming method is used in the cluster head to implement the cluster internal relative positioning. Then, from the sink node, the inter-cluster location fusion is gradually implemented, and finally the absolute positioning of the whole network is realized. Compared with the centralized convex programming algorithm, the proposed algorithm has low computational complexity, small traffic, high positioning accuracy, and does not need to know the signal attenuation factor in the environment in advance, and there is anti-noise ability.


Author(s):  
R. Matanguihan ◽  
E. Sajan ◽  
M. Zachariou ◽  
C. Olson ◽  
Jim Michaels ◽  
...  

1988 ◽  
Vol 130 ◽  
pp. 259-271
Author(s):  
Carlos S. Frenk

Modern N-body techniques allow the study of galaxy formation in the wider context of the formation of large-scale structure in the Universe. The results of such a study within the cold dark matter cosmogony are described. Dark galactic halos form at relatively recent epochs. Their properties and abundance are similar to those inferred for the halos of real galaxies. Massive halos tend to form preferentially in high density regions and as a result the galaxies that form within them are significantly more clustered than the underlying mass. This natural bias may be strong enough to reconcile the observed clustering of galaxies with the assumption that Ω = 1.


Sign in / Sign up

Export Citation Format

Share Document