Papers by Keyword: Cell Culture

Abstract: In this paper, we are investigating the different cultured structures scale in micrometer and nanometer. The experiment have been fabricated four types aluminum substrate structures which included none-structure, micro-structure, nano-structure, and combined micro/nano structure to fulfill the research in osteoblast-like cell (MG 63). Finally we performed the sterilization method to deal with the patterns of alumina sheet product in the clean room. Meanwhile, we demonstrated the osteoblast-like cell (MG63) to culture on the thin film. Finally, we have been used MTT assay study the behavior of cultured osteoblast-like cell to obtain the different properties between none-structure、micro-structure, nano-structure and micro/nano structure for adhesion, elongation and proliferation.

Abstract: Control of adhesion force between cells and medical materials is important for artificial tissue such as tooth, bone and joint. There are many trials to control the adhesion by modifying the surface of culture media. One of these is roughness control of culture media. In this study, the cells cultured on microstructured surface were pushed by a cantilever on a micromanipulator. The deflection of cantilever was measured to calculate the force, and the crucial force when cells were detached from media was quantified as cell adhesion force. Microstructured surface was fabricated from poly-dimethylsiloxane (PDMS). The structure was replicated from Si substrate that was etched through a mask of self-assembled particles. The profile of the mold is cone array of which pitches is same with mask particle's diameter 1 or 5 μm. Thus, the media has regular pits which correspond to the pillar. The effect of pitch and height of the structures on the adhesion force were made clear.

Abstract: The effects of linoleic acid on hepatopancreatic cell culture of the kuruma prawn, Penaeus vannamei were conducted. The culture system consists of 199 media (M 199) supplemented with 0.060 mol/L NaCl, 1.011g/L glucose, 1000 UI/ml penicillin, 1000 μg/ml treptomycin, 20% heat inactivated fetal calf serum (FCS) for primary cells and 10 % for subculture cells. The content of phosphorus in cultured cells was measured. The results show that the growth condition of cultured hepatopancreas cells in P. vannamei was significantly improved by added 160 μmol/L linoleic acid.

Abstract: Solid freeform fabrication, known as rapid prototyping (RP) technology allows in designing the scaffold with pre-defined and controlled external and internal architecture.In this study we produce scaffolds with network of chitosan fibrils that mimic the extracellular matrix produced by the cells. These network scaffolds also consisting of nanoparticles of hydroxyapatite (HA) for stabilisation of scaffolds are characterised by environmental scanning electron microscopy and mechanical properties. ESEM showed that the scaffolds possess macropore (300µm), micropore and fibre network structure. The compressive strength and elastic modulus (E) for the scaffolds are 0.54± 0.02 MPa and 6.13± 0.60 MPa, respectively, which are increasing obviously. The biocompatibility of the woodpile-network scaffolds was investigated with osteoblastic cells. The result showed the distribution and proliferation of osteoblast orients along the chtosan fibre network, preferentially. After 4 weeks of culture, macropore channels are covered by cells in large part,while the areas without chitosan fibre network are covered rarely. The properties of these scaffolds indicate that they can be used for bone tissue engineering applications.

Abstract: Traditional cell-based assays such as cell immunoassay that utilizes plastic (chamber slides, dishes, microtiter plates), Magnetic bead, enzyme-linked immunsorbent assays (ELISA) [1], FACS cell sorting is labor intensive, time consuming, and requires a large numbers of cells or reagents. In this report, a microfluidic device integrated with cell culture, washing, fixation, and antigen-antibody reaction is presented for high-throughput immunoassay. Using this microfluidic device, each assay can be performed on a small number of cells and nanolitre or picolitre of reagents, this is particularly beneficial for rare or expensive cell types such as stem cells, or flow sorted cell populations. The capability of the microfluidic device was demonstrated for seeding human umbilical cord blood mesenchymal stem cells (UC-MSCs) in chambers and detecting the expression of surface markers (CD34, CD44, CD45, CD73, CD105, HLA-DR) by immunofluorescence assay.

Abstract: Dental pulp cell research might open a promising application in tooth tissue regeneration. The aim of this study is to establish a protocol for in vitro culture the human dental pulp stem cells to apply in tissue engineering. Human premolar and impacted third molars were collected and disinfected. Dental pulp fragments were cultured with Dulbecco's Modified Eagle Medium: Nutrient Mixture F-12 (DMEM/F12) medium supplemented with 10% Fetal Bovine Serum (FBS). Dental pulp stem cells (DPSCs) were identified using proliferation assay, RT-PCR and flow cytometry. Growth of DPSCs on dentin surface was assessed by MTT assay. The study showed that we successfully isolated, cultured and characterized dental pulp cells by outgrowth method. Cultured population of cells expressed in high level of Oct4, CD146, CD90, CD44. DPSCs proliferated on chemically and mechanically treated dentin surface. This research provides important information and a basis for further investigations to establish dental tissue engineering protocols.

Abstract: In order to improve the corrosion resistance, the samples made of Mg-Zn-Zr alloy were immersed in 20% or 40% hydrofluoric acid (HF) aqueous solutions for different intervals to prepare magnesium fluoride (MgF₂) coating on the surface. By comparing the surface morphologies, the samples immersed in 20% HF solution for 6 h on which fine particles in nanoscale covered was selected for the further study. Immersion and electrochemical tests showed that the dense MgF₂ coating would improve the corrosion resistance of Mg-Zn-Zr alloy. The corrosion current density (i_corr) decreased from 2.10 μA·cm^-2 to 0.05 μA·cm^-2. The influence of HF treatment on the cytocompatibility was evaluated in vitro. There were significant differences in the cell number between the naked and coated samples after culturing for 3 and 5 days (p<0.05). All the results demonstrate that HF treatment is a promising approach to improve the corrosion resistance and in vitro biocompatibility of Mg-Zn-Zr alloy used as intravascular stents.

Abstract: During the whole process of cell culture, it needs enough air, especially oxygen supply. Therefore, the research about air sparger became significant. There are many influence factors of air sparger are important, including air sparger structure, installation location, ventilation rate. In order to solve these problems, the finite element numerical calculation is used to set a numerical model of air-liquid two-phase flow. This analysis makes clear that the distance between air vent and the bottom of bioreactor has little effect on the air voids, and the air voids is higher by adopting the structure of single air vent compared with the one of distribution ring structure. But the ventilation structure of big distribution ring avoids flooding effectively. The air voids of bioreactor increased with the velocity of ventilation is increased within limits. However, it causes air incomplete dispersion in bioreactor, overflowing from head top of the liquid, flooding and low air voids, if the ventilation velocity is over speed.

Abstract: A crucial factor for in-growth of metallic implants in the bone stock is the rapid cellular acceptance whilst prevention of bacterial adhesion on the surface. Such contradictorily adhesion events could be triggered by surface properties. There already exists fundamental knowledge about the influence of physicochemical surface properties like roughness, titanium dioxide modifications, cleanness, and (mainly ceramic) coatings on cell and microbial behavior in vitro and in vivo. The titanium surface can be equipped with antimicrobial properties by plasma-based copper implantation, which allows the release and generation of small concentrations of copper ions during contact with water-based biological liquids. Additionally, the titanium surface was equipped with amino groups by the deposition of an ultrathin plasma polymer. This coating on the one hand does not significantly reduce the generation of copper ions, and on the other hand improves the adhesion and spreading of osteoblast cells. The process development was accompanied by physicochemical surface analyses like XPS, FTIR, contact angle, SEM, and AFM. Very thin modified layers were created, which are resistant to hydrolysis and delamination. These titanium surface functionalizations were found to have either an antimicrobial activity or cell-adhesive properties. Intramuscular implantation of titanium samples coated with the cell-adhesive plasma polymer in rats revealed a reduced inflammation reaction compared to uncoated titanium.

Abstract: Carbon nanotubes (CNT) and their derivatives with different structure and compositions have unique features. In the present study, cell proliferation was performed on various nanotubes such as single walled CNTs, multiwalled CNTs and imogolite which is nanotubes of aluminosilicate. SEM observation of the growth of osteoblast-like cells cultured on CNTs showed the morphology fully developed for the whole direction, which was different from that extended to the one direction on the usual scaffold. Numerous filopodia were grown from cell edge, extended far long and combined with CNT meshwork. Apatite precipitation in simulated body fluid, affinity for proteins and saccharides, and nanosize meshwork structure with large porosity would be the properties responsible for these cell adhesion and growth. Imogolite showed the similar properties to CNTs. Nanotubes could be the favorable materials for biomedical applications.