Biocompatibility of electrospinning polycaprolactone, polylactic acid, their blends and copolymers scaffolds in in vitro tests if mesenchyme stem cells

Background. Biodegradable polymers are one of the most promising groups of materials suitable for creating tissue-engineered scaffolds. The high interest in biopolymers is associated with the possibility of creating scaffolds with desired properties, through the use of mixtures and copolymers. The determination of the key parameters of biocompatibility is the basic purpose for testing created materials.Objective. To perform the comparative in vitro study of biocompatibility properties of biopolymer scaffolds produced using polycaprolactone, polylactic acid, their mixtures and copolymers by electrospinning technology.Design and methods. The adhesion properties and cytotoxicity of scaffolds made from polycaprolactone, polylactic acid, copolymer of L- and D-isoforms of lactic acid, their mixtures and co-polymers with the addition of polyglycolic acid were investigated after scaffolds co-cultivation with human mesenchyme stem cells (MSC).Results. The largest number of spread spindle-shaped MSCs was on the surface of polymers containing polyglycolic acid. Besides, the cells on the surface of the copolymer with polyglycolic acid had the morphology closest to the control. The lowest number of living cells was found on the surface of polylactic acid scaffolds, and the highest on the surface of samples from of polycaprolactone and polylactic acid blend.Conclusion. Thus, all tested polymers had good adhesion properties in experiments with human mesenchyme stem cells were possessed by biodegradable polymers with the addition of polyglycolic acid.

Investigation of Intestinal Enzyme Activity and Effects of Non-starch Polysaccharide on it

Background and Purpose: Shigella is a human shigellosis and its lipopolysaccharide is identified by 4TLR. The 4TLR is a family of pseudo-TOLL receptors and many immune routes are triggered by stimulating these receptors. Many studies show increasing of 4TLR expression in Mesenchyme stem cells under the influence of lipopolysaccharide. The main objective of this study was to identify the appropriate lipopolysaccharide of Shigella strains by stimulating the immune system for vaccine studies. Materials and Methods: In this experimental study, the stem cell of human Mesenchymal derived from bone marrow was treated by three dilution of 0.1, 0.01, and 0.001 extract of Shigella strains (Flexneri, Dysentery and Sonnei) containing lipopolysaccharide. Then, the expression of 4TLR at RNA level was evaluated by RT-PCR and Q-PCR techniques. Cells treated with phosphate buffer saline were considered as control group. Findings: The expression of 4TLR was observed in all treatments groups except for treatment groups with relative concentration of 0.001 sonnei and dysentery as well as control group. Changes in 4TLR expression were dose-dependent on all treatment groups. The highest expression was related to the treatment with Shigella Flexneri extract and the smallest was related to Shigella sonnei. The use of pure lipopolysaccharide of Escherichia coli as a positive control showed that the lipopolysaccharide in Shigella extract is responsible for increasing the expression of 4TLR. Conclusion: given the increased expression of 4TLR by Shigella extract, this extract is recommended to increase the efficacy of the vaccine.

The Effect of Adipose Tissue-Derived Mesenchymal Stem Cells on Regeneration of Uterine Scars

<p><strong>OBJECTIVE:</strong> The mesenchymal stem cell application to uterine healing scars may provide better tissue strength.<br /><strong>STUDY DESIGN:</strong> Hysterectomy was performed on rats, and the wound recovery as a result of primary suturing was evaluated as tissue stretching and the positive histopathological effects. The mesenchymal stem cells originating from the adipose tissue were used during the healing period of the wound and would differentiate to mesenchyme-originated cells present in intact tissue for an optimum level of healing.<br /><strong>RESULTS:</strong> The weights of non-incised uterine horns in the control group were found to be significantly higher than the weights of the incised uterine horns (z=2.52, p=0.012). In the experiment group, the weights of the incised uterine horns were found to be significantly higher than the non-incised uterine horns (z=2.527, p=0.012). In the control group, the non-incised uterine horns withstood the stretching test to a higher extent than the incised horns, and a significant difference was found between the stretching values (z=2.51, p=0.012). In the experiment group, the incised uterine horns withstood the stretching tests to a higher extent than the non-incised uterine horns; however, there was no significant difference between the stretching tests (z=1.540, p=0.123).<br /><strong>CONCLUSION:</strong> Adipose tissue-originated mesenchyme stem cells were observed to increase the tissue stretching during wound healing.<br /><br /></p>

Investigations into the Biocompatibility of Nanohydroxyapatite Coated Magnetic Nanoparticles under Magnetic Situation

Regenerative medicine consisting of cells and materials offers a new approach for repairing and regenerating the organs and tissues. More and more researches focused on the magnetic nanobiomaterials due to its superior advantages to traditional materials. However, the toxicity of nanosized magnetic particles cannot be ignored, especially under the magnetic situation. This study aims to study the biocompatibility of nanohydroxyapatite (n-HA-) coated magnetic nanoparticles under the magnetic situation. n-HA-coated magnetic nanoparticles were fabricated through an ultrasound-assisted coprecipitation method. Subsequently, these materials were analyzed by transmission electron microscope (TEM) and X-ray diffraction (XRD) and then were cultured with mesenchyme stem cells derived from human bone marrow (hMSC-BM). In vitro experiment proved the satisfactory biocompatibility of n-HA-coated magnetic nanoparticles. These important factors (ALP, OCN, and OPN) influence the osteogenic differentiation of hMSC-BM. It was found that the hMSC-BM with combination of n-HA/Fe3O4and magnetic stimulation presented higher degree of osteoblast-related markers than that in each alone. This research demonstrated that a novel nanohydroxyapatite coated magnetic nanoparticle is safe under the magnetic situation. Therefore, these n-HA-coated magnetic nanoparticles are promising biomagnetic materials for future applications.

Biocompatibility Evaluation of Co-Ribbons Prepared by Melt-Spinning

Ribbons of Co-base alloy were tested as biocompatible material at in vitro process to develop in the future an implant dental device. Regarding research on the effect of rapid solidification on Co-alloys, few or absent studies to date have been assessed for the evaluation of surfaces properties when the alloys are placed in contact with human mesenchyme stem cells (hMSC). The Co-based ribbons were prepared by rapid solidification process and its surface attached with human adipose-derived mesenchymal stem cells to determine it toxicity, cells viability, adhesive and proliferation of the cells. Experimental results showed that Co-based ribbons are non-toxic material with 80% of increased cellular adhesion and exhibited excellent biocompatibility.