scholarly journals Maintenance and Acceleration of Pericellular Matrix Formation within 3D Cartilage Cell Culture Models

Cartilage ◽  
2019 ◽  
pp. 194760351987083 ◽  
Author(s):  
Hamza A. Owida ◽  
Nicola L. Kuiper ◽  
Ying Yang
Keyword(s):  
Time Course ◽  
Type Ii Collagen ◽  
Pericellular Matrix ◽  
Type Vi Collagen ◽  
Extracellular Matrix Components ◽  
Agarose Hydrogel ◽  
Culture Models ◽  
The Media ◽  
Media Types ◽  
Cell Culture Models

Objective In native articular cartilage, chondrocytes are surrounded by a thin pericellular matrix (PCM) forming chondrons. The PCM is exclusively rich in type VI collagen. The retention of the PCM has a significant influence on the metabolic activity of the chondrocytes. Design This study investigated the influence of 2 hydrogels (hyaluronic acid [HA] and agarose) and 2 media compositions (basal and chondrogenic) on the preservation/maintenance and acceleration of PCM formation over a 21-day time course. Different combinations of chondrocytes, chondrons, and mesenchymal stem cells (MSCs) were studied. Results Both hydrogels preserved chondrons PCM from day 1 up to 21-day culture regardless of media composition. Type VI collagen immunostaining of the cultured chondrons appeared both dense and homogenous. The presence of MSCs did not influence this outcome. At day 1, type VI collagen was not present around chondrocytes alone or their co-culture with MSCs. In the HA hydrogel, type VI collagen was located within the PCM after 7 days in both mono- and co-cultures. In the agarose hydrogel, collagen VI was located within the PCM at 7 days (co-cultures) and 14 days (monocultures). In both hydrogel systems, chondrogenic media enhanced the production of key extracellular matrix components in both mono- and co-cultures in comparison to basal media (11.5% and 14% more in glycosaminoglycans and type II collagen for chondrocytes samples at day 21 culture samples, respectively). However, the media types did not enhance type VI collagen synthesis. Conclusion Altogether, a 3D chondrogenic hydrogel environment is the primary condition for maintenance and acceleration of PCM formation.

ENRICHING MEDIA MERCHANDISE SARANA PENUNJANG PROMOSI STUDI KASUS PADA BOOKSTORE

CCIT Journal ◽  
2014 ◽  
Vol 7 (3) ◽  
pp. 420-436
Author(s):  
Dewi Immaniar ◽  
Sudaryono Sudaryono ◽  
Ayu Ningrum
Keyword(s):  
Visual Media ◽  
Test Duration ◽  
Media Campaign ◽  
Business World ◽  
Retail Business ◽  
The Media ◽  
Media Types ◽  
The Times ◽  
A Company

Talk about retail business can not be separated from the importance of service to consumers and good quality goods . But at the present time due to intense competition in the business world , the service and quality of goods is not enough to be able to increase revenue and attract customers loyal . This makes companies think hard to survive and stable in the business . One of them is by using a media campaign in this regard more toward print or visual media is indirectly felt the value of their effectiveness in communicating product marketing programs . PT . Times Prima Indonesia is a company engaged in the retail book with the name of the Times bookstores . Based on the analysis of the company’s problems requires additional media types supporting more varied and creatif promotion of existing ones, which will be used as a complement and a media campaign as well as to enrich the data renewal campaign design to capture the interest of consumers in which one form of the media campaign is shaped merchandise . Therefore , do Enriching ( enrich ) media campaign merchandise before it is less varied and has not formed a company image . The methodology used is the analysis, observation and design . Besides the new design has been tested with the implemented test duration for 6 months, and greatly increases the perceived contribution , this is evidenced by the chart sales increasing each month.

scholarly journals A buffered media system for yeast batch culture growth

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Rianne C. Prins ◽  
Sonja Billerbeck
Keyword(s):  
Nitrogen Source ◽  
Ammonium Sulfate ◽  
Batch Culture ◽  
Biomass Production ◽  
Buffering Capacity ◽  
Drop Out ◽  
Batch Cultures ◽  
Media System ◽  
The Media ◽  
Media Types

Abstract Background Fungi are premier hosts for the high-yield secretion of proteins for biomedical and industrial applications. The stability and activity of these secreted proteins is often dependent on the culture pH. As yeast acidifies the commonly used synthetic complete drop-out (SD) media that contains ammonium sulfate, the pH of the media needs to be buffered in order to maintain a desired extracellular pH during biomass production. At the same time, many buffering agents affect growth at the concentrations needed to support a stable pH. Although the standard for biotechnological research and development is shaken batch cultures or microtiter plate cultures that cannot be easily automatically pH-adjusted during growth, there is no comparative study that evaluates the buffering capacity and growth effects of different media types across pH-values in order to develop a pH-stable batch culture system. Results We systematically test the buffering capacity and growth effects of a citrate-phosphate buffer (CPB) from acidic to neutral pH across different media types. These media types differ in their nitrogen source (ammonium sulfate, urea or both). We find that the widely used synthetic drop-out media that uses ammonium sulfate as nitrogen source can only be effectively buffered at buffer concentrations that also affect growth. At lower concentrations, yeast biomass production still acidifies the media. When replacing the ammonium sulfate with urea, the media alkalizes. We then develop a medium combining ammonium sulfate and urea which can be buffered at low CPB concentrations that do not affect growth. In addition, we show that a buffer based on Tris/HCl is not effective in maintaining any of our media types at neutral pH even at relatively high concentrations. Conclusion Here we show that the buffering of yeast batch cultures is not straight-forward and addition of a buffering agent to set a desired starting pH does not guarantee pH-maintenance during growth. In response, we present a buffered media system based on an ammonium sulfate/urea medium that enables relatively stable pH-maintenance across a wide pH-range without affecting growth. This buffering system is useful for protein-secretion-screenings, antifungal activity assays, as well as for other pH-dependent basic biology or biotechnology projects.

scholarly journals Factors to consider when interrogating 3D culture models with plate readers or automated microscopes

2021 ◽  
Author(s):  
Terry Riss ◽  
O. Joseph Trask
Keyword(s):  
Cell Culture ◽  
Three Dimensional ◽  
3D Culture ◽  
Fluorescent Imaging ◽  
Culture Models ◽  
Assay Methods ◽  
Diffusion Rates ◽  
Cell Culture Models ◽  
Dimensional Cell ◽  
Cells Cultured

AbstractAlong with the increased use of more physiologically relevant three-dimensional cell culture models comes the responsibility of researchers to validate new assay methods that measure events in structures that are physically larger and more complex compared to monolayers of cells. It should not be assumed that assays designed using monolayers of cells will work for cells cultured as larger three-dimensional masses. The size and barriers for penetration of molecules through the layers of cells result in a different microenvironment for the cells in the outer layer compared to the center of three-dimensional structures. Diffusion rates for nutrients and oxygen may limit metabolic activity which is often measured as a marker for cell viability. For assays that lyse cells, the penetration of reagents to achieve uniform cell lysis must be considered. For live cell fluorescent imaging assays, the diffusion of fluorescent probes and penetration of photons of light for probe excitation and fluorescent emission must be considered. This review will provide an overview of factors to consider when implementing assays to interrogate three dimensional cell culture models.

scholarly journals Turnover of the Active Fraction of IRS1 Involves Raptor-mTOR- and S6K1-Dependent Serine Phosphorylation in Cell Culture Models of Tuberous Sclerosis

2006 ◽  
Vol 26 (17) ◽  
pp. 6425-6434 ◽  
Author(s):  
O. Jameel Shah ◽  
Tony Hunter
Keyword(s):  
Cell Culture ◽  
Tuberous Sclerosis ◽  
High Speed ◽  
Serine Phosphorylation ◽  
Feedback Signal ◽  
Insulin Receptor Substrates ◽  
Igf I ◽  
Culture Models ◽  
Cell Culture Models

ABSTRACT The TSC1-TSC2/Rheb/Raptor-mTOR/S6K1 cell growth cassette has recently been shown to regulate cell autonomous insulin and insulin-like growth factor I (IGF-I) sensitivity by transducing a negative feedback signal that targets insulin receptor substrates 1 and 2 (IRS1 and -2). Using two cell culture models of the familial hamartoma syndrome, tuberous sclerosis, we show here that Raptor-mTOR and S6K1 are required for phosphorylation of IRS1 at a subset of serine residues frequently associated with insulin resistance, including S307, S312, S527, S616, and S636 (of human IRS1). Using loss- and gain-of-function S6K1 constructs, we demonstrate a requirement for the catalytic activity of S6K1 in both direct and indirect regulation of IRS1 serine phosphorylation. S6K1 phosphorylates IRS1 in vitro on multiple residues showing strong preference for RXRXXS/T over S/T,P sites. IRS1 is preferentially depleted from the high-speed pellet fraction in TSC1/2-deficient mouse embryo fibroblasts or in HEK293/293T cells overexpressing Rheb. These studies suggest that, through serine phosphorylation, Raptor-mTOR and S6K1 cell autonomously promote the depletion of IRS1 from specific intracellular pools in pathological states of insulin and IGF-I resistance and thus potentially in lesions associated with tuberous sclerosis.

Cell culture models of the ocular barriers

2005 ◽  
Vol 60 (2) ◽  
pp. 207-225 ◽  
Author(s):  
Margit Hornof ◽  
Elisa Toropainen ◽  
Arto Urtti
Keyword(s):  
Cell Culture ◽  
Culture Models ◽  
Cell Culture Models

scholarly journals Ivermectin effectively inhibits hepatitis E virus replication, requiring the host nuclear transport protein importin α1

2021 ◽  
Author(s):  
Yunlong Li ◽  
Zhijiang Miao ◽  
Pengfei Li ◽  
Ruyi Zhang ◽  
Denis E. Kainov ◽  
...  
Keyword(s):  
Hepatitis E Virus ◽  
Nuclear Transport ◽  
Hepatitis E ◽  
Term Treatment ◽  
Cellular Target ◽  
Long Term Treatment ◽  
Culture Models ◽  
Transport Complex ◽  
Cell Culture Models

AbstractWe show that ivermectin, an FDA-approved anti-parasitic drug, effectively inhibits infection with hepatitis E virus (HEV) genotypes 1 and 3 in a range of cell culture models, including hepatic and extrahepatic cells. Long-term treatment showed no clear evidence of the development of drug resistance. Gene silencing of importin-α1, a cellular target of ivermectin and a key member of the host nuclear transport complex, inhibited viral replication and largely abolished the anti-HEV effect of ivermectin.

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