Abstract:
:The thermo-responsive polymer poly(N-isopropylacrylamide) has received widespread attention for its in vitro application in the non-invasive, non-destructive release of adherent cells on two dimensional surfaces. In this study, 3D non-woven scaffolds fabricated from poly(propylene) (PP), poly(ethylene terephthalate) (PET), and nylon that had been grafted with PNIPAAm were tested for their ability to support the proliferation and subsequent thermal release of HC04 and HepG2 hepatocytes. Hepatocyte viability and proliferation were estimated using the Alamar Blue assay and Hoechst 33258 total DNA quantification. The assays revealed that the pure and grafted non-woven scaffolds maintained the hepatocytes within the matrix and promoted 3D proliferation comparable to that of the commercially available Algimatrix™ alginate scaffold. Albumin production and selected cytochrome P450 genes expression was found to be superior in cells growing on pure and grafted non-woven PP scaffolds as compared to cells grown as a 2D monolayer. Two scaffolds, namely, PP-g-PNIPAAm-A and PP-g-PNIPAAm-B were identified as having far superior thermal release capabilities; releasing the majority of the cells from the matrices within 2 h. This is the first report for the development of 3D non-woven, thermo-responsive scaffolds able to release cells from the matrix without the use of any enzymatic assistance or scaffold degradation.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Rossouw CL,Chetty A,Moolman FS,Birkholtz LM,Hoppe H,Mancama DTdoi
10.1002/bit.24469subject
Has Abstractpub_date
2012-08-01 00:00:00pages
2147-58issue
8eissn
0006-3592issn
1097-0290journal_volume
109pub_type
杂志文章abstract::Non-invasive methods for online monitoring of biotechnological processes without compromising the integrity of the reactor system are very important to generate continuous data. Even though calorimetry has been used in conventional biochemical analysis for decades, it has not yet been specifically applied for online d...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24815
更新日期:2013-05-01 00:00:00
abstract::RNA sequencing (RNASeq) has been widely used to associate alterations in Chinese hamster ovary (CHO) cell gene expression with bioprocess phenotypes; however, alternative messenger RNA (mRNA) splicing, has thus far, received little attention. In this study, we utilized RNASeq for transcriptomic analysis of a monoclona...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27365
更新日期:2020-08-01 00:00:00
abstract::A second generation flow contraction device was developed and modeled which allows cells to be subjected to well-defined hydrodynamic forces. Studies were conducted with this system on wild-type Chinese Hamster Ovary cells (CHO-K1) and a strain of CHO cells which expresses the human Bcl-2 triangle gene (CHO-bcl-2). In...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21476
更新日期:2007-11-01 00:00:00
abstract::Calculation of kinetic constants of an enzymatic reaction in organic solvents requires knowledge of the functional active-site concentration in organic solvents, and this can be significantly different than that in water. An experimental method for active-site titration of serine proteases in organic media has been de...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960505)50:3<329::AID-BIT
更新日期:1996-05-05 00:00:00
abstract::The relationship between local mass transfer coefficient and fluid velocity in heterogenous biofilms was investigated by combining microelectrodes and confocal scanning laser microscopy (CSLM). The biofilms were grown for up to 7 days and consisted of cell clusters separated by interstitial channels. Mass transfer coe...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19971220)56:6<681::AID-BIT
更新日期:1997-12-20 00:00:00
abstract::In order to predict the potential benefit associated with mixing devices designed to introduce periodic light modulations in dense cultures of microalgae, it is necessary to develop a quantitative understanding of the relationship between the frequency of the modulations and the resulting photosynthetic efficiency enh...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280709
更新日期:1986-07-01 00:00:00
abstract::Mass balances were performed on an alkaline lysis operation for the primary recovery of supercoiled plasmid DNA as part of a process for plasmid gene preparation. Escherichia coli DH5alpha/pSVbeta was cultured in defined medium by fed-batch fermentation and harvested at the end of the exponential phase. Alkaline lysis...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10166
更新日期:2002-03-30 00:00:00
abstract::Alcoholic fermentation of cheese whey permeate was investigated using a recombinant flocculating Saccharomyces cerevisiae, expressing the LAC4 (coding for beta-galactosidase) and LAC12 (coding for lactose permease) genes of Kluyveromyces marxianus enabling for lactose metabolization. Data on yeast fermentation and gro...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20010305)72:5<507::aid-bit1014>3
更新日期:2001-03-05 00:00:00
abstract::Control of cell shape and behavior through the micropattern technique by spatial immobilization of adhesive proteins on a surface has provided novel insights in several aspects of cell biology, such as tissue morphogenesis, cell growth and cell differentiation, and apoptosis. In this work, we present the use of poly(e...
journal_title:Biotechnology and bioengineering
pub_type: 信件
doi:10.1002/bit.22997
更新日期:2011-04-01 00:00:00
abstract::Point and 95% confidence interval estimates of the true growth yield and maintenance coefficient are reported for four pure cultures andtwo mixed cultures of Lactobacillus bulgaricus and Streptococcus thermophilus grown anaerobically on 3% nonfat dry milk using batch followed by fed batch culture. An improved method o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280619
更新日期:1986-06-01 00:00:00
abstract::Mechanical forces regulate the structure and function of many tissues in vivo; recent results indicate that the mechanical environment can decisively influence the development of engineered tissues cultured in vitro. To investigate the effects of the hydrodynamic environment on tissue-engineered cartilage, primary bov...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20000220)72:4<402::aid-bit1002>3
更新日期:2001-02-20 00:00:00
abstract::Generating stable, high-producing cell lines for recombinant protein production requires an understanding of the potential limitations in the cellular machinery for protein expression. In order to increase our understanding of what makes a stable high producer, we have generated a panel of 17 recombinant monoclonal an...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22158
更新日期:2009-03-01 00:00:00
abstract::In this study, a useful method was developed to fabricate array patterns of microparticles not on electrode surfaces, but on arbitrary surfaces, using negative-dielectrophoresis (n-DEP). First, electrodes were designed and electric field simulations were performed to manipulate microparticles toward target areas. Base...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22445
更新日期:2009-11-01 00:00:00
abstract::The present study evaluated the influence of water activity and lactose concentration on the synthesis of galactooligosaccharides (GOS), by means of a hyperthermophilic beta-glycosidase in an organic system. The production of GOS gradually grew as water activity increased in the reaction system; later, their synthesis...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20824
更新日期:2006-04-20 00:00:00
abstract::The misfolding of polypeptide chains and aggregation into the insoluble inclusion body state is a serious problem for biotechnology and biomedical research. Developing a rational strategy to control aggregation requires understanding the mechanism of polymerization. We investigated the in vitro aggregation of P22 tail...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19970520)54:4<333::AID-BIT
更新日期:1997-05-20 00:00:00
abstract::Clostridium formicoaceticum homofermentatively converts lactate to acetate at 37 degrees C and pH 6.6-9.6. However, this fermentation is strongly inhibited by acetic acid at acidic pH. The specific growth rate of this organism decreased from a maximum at pH 7.6 to zero at pH 6.6. This inhibition effect was found to be...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260340807
更新日期:1989-10-20 00:00:00
abstract::The performance and microbial communities of three differently inoculated biotrickling filters removing dimethyl sulfide (DMS) were compared. The biotrickling filters were inoculated with Thiobacillus thioparus TK-m (THIO), sludge (HANDS) and sludge + T. thioparus TK-m + Hyphomicrobium VS (HANDS++), respectively. The ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21059
更新日期:2007-03-01 00:00:00
abstract::The twin arginine translocation (Tat) pathway occurs naturally in E. coli and has the distinct ability to translocate folded proteins across the inner membrane of the cell. It has the potential to export commercially useful proteins that cannot be exported by the ubiquitous Sec pathway. To better understand the biopro...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24384
更新日期:2012-04-01 00:00:00
abstract::Soluble steel factor (SF) is a potent stimulator of hematopoietic progenitor cell proliferation in vitro, and cytokine combinations that include SF can support extensive expansions of hematopoietic cells. Recently, we showed that very primitive progenitor cells from normal human bone marrow require exposure to very hi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:1999-05-20 00:00:00
abstract::The methanotrophic bacterium Methylococcus capsulatus is capable of assimilating methane and oxygen into protein-rich biomass, however, the diverse metabolism of the microorganism also allows for several undesired cometabolic side-reactions to occur. In this study, the ammonia cometabolism in Methylococcus capsulatus ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27113
更新日期:2019-11-01 00:00:00
abstract::Liquid membrane bilayers, generated by bacteriorhodopsin on a supporting membrane, exhibit photo osmosis. The phenomenon has been shown to be a consequence of light-induced electrical potential differences which develop across the liquid membrane bilayer due to the light-driven proton pumping action of bacteriorhodops...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260310602
更新日期:1988-04-20 00:00:00
abstract::An efficient method was developed for media separation and cell collection for eukaryotic cells growing in suspension. The method is based on tangential flow microfiltration using an open channel arrangement in a hollow fiber configuration. Best results (highest processing flux rate) for polysulfone hollow fibers were...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260480412
更新日期:1995-11-20 00:00:00
abstract::The productivity of Escherichia coli as a producer of recombinant proteins is affected by its metabolic properties, especially by acetate production. Two commercially used E. coli strains, BL21 (lambdaDE3) and JM109, differ significantly in their acetate production during batch fermentation at high initial glucose con...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19980105)57:1<71::aid-bit9
更新日期:1998-01-05 00:00:00
abstract::We have previously reported the development of a novel protein expression system based on Ralstonia eutropha. In this study we report on the influence of gene copynumber on recombinant protein expression in R. eutropha. We compare recombinant gene stability and expression levels of chromosomal integration with a plasm...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10756
更新日期:2003-10-05 00:00:00
abstract::A two-stage deterministic model of the growth of Saccharomyces cerevisiae is presented. The cell cycle of this organism was used to suggest the basic model structure. The model represents the preparatory processes of substrate uptake and conversion separately from replication and division. The regulation of the fracti...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260190209
更新日期:1977-02-01 00:00:00
abstract::Among various routes for the biological hydrogen production, the NAD(P)H-dependent pentose phosphate (PP) pathway is the most efficient for the dark fermentation. Few studies, however, have focused on the glucose-6-phosphate 1-dehydrogenase, encoded by zwf, as a key enzyme activating the PP pathway. Although the gluco...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.23259
更新日期:2011-12-01 00:00:00
abstract::The accumulation of inorganic phosphate inhibits protein synthesis in cell-free protein synthesis reactions that are energized by high-energy-phosphate-containing compounds. This study developed a new scheme for supplying energy using dual energy sources to enhance the regeneration of ATP and lower the rate of phospha...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21337
更新日期:2007-08-15 00:00:00
abstract::Coastal bermudagrass was pretreated by a low-temperature ammonia fiber explosion (AFEX) process, which soaked the grass in liquid ammonia and then explosively released the pressure. Saccharifying enzymes were systematically applied to the AFEX-treated grass corresponding to low, medium, and high loadings of cellulase/...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260440914
更新日期:1994-11-05 00:00:00
abstract::A method was developed for obtaining high signal-to-noise 13C NMR spectra of intracellular compounds in metabolically active cultured cells. The method allows TCA cycle labeling kinetics to be determined in real time without significant oxygen transport limitations. Cells were immobilized on the surface of nonporous m...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20191
更新日期:2004-09-30 00:00:00
abstract::A whole cell-based optical sensing system for copper was developed based on Saccharomyces cerevisiae cells harboring plasmid pYEX-GFPuv. The basis of this system was the ability of the transcriptional activator protein Ace1 present in S. cerevisiae to control the expression of the reporter protein, GFPuv. When copper ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20331
更新日期:2004-12-05 00:00:00