China 
Africa 
Explore chapters and articles related to this topic
Trends in Biotechnology
Published in Firdos Alam Khan, Biotechnology Fundamentals, 2020
Skin is maybe the only organ that can be artificially produced from in vitro cell culture and can be used for grafting when skin is severely damaged due to severe burns/damage. The keratinocytes comprise 90% of the epidermis of skin and they are responsible for giving rise to the dead cells making the external cornified layer of the skin, and their proliferation is facilitated by the fibroblasts that are found in the dermis layer of the skin. Since fibroblasts are useful for culturing keratinocytes, fibroblast cells called 3T3 cells were used to cover the bottom of a vessel before adding epidermal cells for culturing. Culture media was added with epidermal growth factors, cholera toxin, and a mixture of other growth factors. It has been found that only 1% to 10% of epidermal cells proliferate, others having already started the process of differentiation. These cells form colonies, are separated again, and are transferred to fresh culture to allow better growth. The process of separating cells from colonies and reculturing them is continued to discourage stratification of cell layers and permit the cell colonies to become confluent, forming a sheet of pure epithelium. The cells of this sheet of epithelium are linked by desmosomes. This cultured epithelium can be detached from the vessel using the enzyme dispase, washed, and brought to the hospital to be used for grafting on patients with severe burns.
Recent Advances of Alginate Biomaterials in Tissue Engineering
Published in Shakeel Ahmed, Aisverya Soundararajan, Marine Polysaccharides, 2018
Jayachandran Venkatesan, Sukumaran Anil, Sandeep Kumar Singh, Se-Kwon Kim
Disadvantages to use alginate alone in skin tissue development are due to its mechanical properties and poor cell interaction. To overcome this issue, alginate is often combined with other materials (chitosan, silk, gelatin, proteins, synthetic polymers, etc.) [60]. Several studies suggest that a chitosan-alginate polyelectrolyte complex shows excellent wound dressing and accelerates wound healing in animal models. The chitosan/alginate polyelectrolyte system has advantages in terms of its higher mechanical strength, resistance to pH and effective delivery of molecules. Bierhalz et al. (2016) developed a chitosan–alginate polyelectrolyte complex system with different mass ratios for skin tissue engineering. The developed membranes had greater thickness, roughness, etc. [62]. In another study, chitosan-alginate scaffolds were developed with a pore size of 40 μm with a tensile strength of 0.564% ± 0.0.018% MPa. Its swelling ratio was 27.5% ± 0.28%, with a mass loss percentage of 10% ± 0.33% after 4 weeks of degradation. Mouse fibroblast 3T3 cells were able to adhere and proliferate well in the blended scaffold [63]. Fujimori et al. developed laminin-derived peptide-conjugated alginate and chitosan [64]. In addition, chitosan-alginate were used to deliver stem cells [65].
Potentials of Polyhydroxyalkanoates as Materials for Constructing Cell Scaffolds in Tissue Engineering
Published in Tatiana G. Volova, Yuri S. Vinnik, Ekaterina I. Shishatskaya, Nadejda M. Markelova, Gennady E. Zaikov, Natural-Based Polymers for Biomedical Applications, 2017
Tatiana G. Volova, Yuri S. Vinnik, Ekaterina I. Shishatskaya, Nadejda M. Markelova, Gennady E. Zaikov
The nanometer surface roughness also affects cell adhesion and proliferation. However, some data suggest that cell adhesion is greater on rough surfaces than on polished ones, while other studies show that cells behave in a similar fashion on surfaces with different degrees of roughness. The study of the roughness of PHA film surfaces yielded the following results: the root mean squared roughness (Rq) of polylactide films was 241.629 nm – twice as high as the corresponding parameter of the films prepared from the PHA copolymers. The Rq values were similar for the P3HB homopolymer and for the copolymers of 3-hydroxybutyrate with 4HB, 3HV, and 3HHx, falling within the 109–113 nm range (Nikolaeva et al., 2011). In that study, biocompatibility of the films was evaluated in vitro in the culture of mouse fibroblast NIH 3T3 cells. Counts of cells stained using Romanowsky dyes attached to and growing on the PHA films that were performed at different time points of the experiment recorded significantly lower abundance of cells on the polylactide film than on the films prepared from any of the PHAs. None of the PHA films directly contacting fibroblast NIH 3T3 cells affected adversely their adhesion and growth. Cells attached to all films were well spread and most of them were star-shaped, which indicated their viability.
Folate-mediated magnetic and pH/GSH dual-responsive metal-polymer-coordinated nanocomplexes for joint chemo/chemodynamic anti-breast cancer therapy
Published in Journal of Biomaterials Science, Polymer Edition, 2023
Zhuo Lan, Xiaopei Tan, Cheng Chen, Yu Cao, Yu Wan, Shun Feng
The cytotoxicity in vitro was investigated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay using mouse mammary tumor cell (4T1) and mouse fibroblast 3T3 cells (3T3). 4T1 cells were seeded in a 96-well plate and grown in Dulbecco’s modified Eagle’s medium (DMEM) supplemented with 10% (v/v) fetal bovine serum (FBS), 50 mg/mL penicillin and 50 mg/mL streptomycin at 37 °C with 5% CO2. After the incubation period, the cells were treated with different concentrations of DOX (0.00925, 0.0925, 0.925, and 9.25 μg/mL), FA-β-CD@Cu2+@GA@Fe3O4 (0.125, 1.25, 12.5, and 125 μg/mL) and FA-β-CD/DOX@Cu2+@GA@Fe3O4 (0.125, 1.25, 12.5 and 125 μg/mL). 48 h post-incubation, MTT solution was added to each well, and cells were incubated for another 4 h. Then, an enzyme-linked immunosorbent assay (ELISA) reader was used to measure the absorbance of the suspension.
A review on Rhodamine-based Schiff base derivatives: synthesis and fluorescent chemo-sensors behaviour for detection of Fe3+ and Cu2+ ions
Published in Journal of Coordination Chemistry, 2023
In 2013, Thennasaru et al. synthesized three different Rhodamine-based chemosensors (probe-5) for identification of intracellular Cu2+ ions in living keratinocyte cells. Using UV-visible analysis and fluorescence spectroscopic techniques, the researchers monitored the binding properties of the metal ion with the probe, finding that the absorption intensities enhanced by 45 folds at 561 nm and fluorescence intensities enhanced at 561 nm when Cu2+ ions (10 M) were added to the probe (10−5 M) in aqueous 10−2 M tris HCl–CH3CN (1: 1 v/v, pH 7.4), due to opening of the spirolactam ring. S1 and S2 formed a complex with Cu2+ ion with 1:2 stoichiometry. The sensor S3 contains a triazole ring and pyridine ring; pyridine ring is less basic than triazole, so S3 prefers to form a complex with Cu2+ ions in a 1:1 stoichiometry due to N-atom of triazole ring acting as the donor site. This was confirmed by Job’s plot, IR, 13C NMR, and ES-spectroscopy. The pyridine-N does not participate in complex formation, as analyzed by DFT calculations. The geometry of S3 with Cu2+ ion was confirmed as distorted tetragonal geometry. The limit of detection was 1.5 × 10−8 M. Bioassays showed that the S3 sensor was more selective towards intracellular Cu2+ ions in living HaCaT human keratinocyte cells and was non-toxic to NIH 3T3 cells at low concentrations [43].
Fabrication of novel ruthenium loaded silk fibroin nanomaterials for fingolimod release improved antitumor efficacy in hepatocellular carcinoma
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Dong Li, Chenmei Xia, Xia Chen, Qianqian Li, Jian Li, Xiaoqi Qian
Using myriocin's structure, fingolimod (2-amino-2[2-(4-octyl phenyl) ethylethyl]-1,3-propanediol, FTY720) is synthesized (a fungal metabolite of the Chinese herb). Inhibiting S1P (1-phosphate-neural sheath) action is an efficient immunosuppressant [47]. A novel oral drug for multiple sclerosis, FTY720, was authorized by the US Food and Drug Administration (FDA) in 2010. T7-FTY720@SF-RuNMs drug delivery system was developed in this work to increase treatment efficacy by targeting the tumour and releasing FTY720 locally. According to Scheme 1, SFs were utilized as a shell material to cover RuNMs before T7 were adsorbed on the surfaces of SF-Ru nanomaterials before incorporating FTY720 into the peptides. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used to examine the shape and size parameters of the SF-Ru and T7-SF-RuNMs that were synthesized (DLS). Different pH and ionic strength settings were used to study the release of T7-FTY720@SF-RuNMs. It was shown that T7-FTY720@SF-RuNMs were highly cytotoxic to human liver cells (HepG2 cells) and NIH-3T3 fibroblast cells (NIH-3T3 cells). It was also tested for T7-FTY720@SF-RuNMs ability to kill cancer cells in vivo and in vitro. These findings demonstrated that T7-FTY720@SF-RuNMs might successfully aggregate in tumour areas and increase antitumor activity. Liver cancer therapy may benefit from a new delivery method.