Actin assessment in addition to specific immuno-fluorescence staining to demonstrate rickettsial growth in cell culture

Fish scale derived hydroxyapatite incorporated 3D printed PLA scaffold for bone tissue engineering

Discover the innovative approach of utilizing fish scales to derive hydroxyapatite, coupled with a 3D printed PLA scaffold, paving a novel avenue for bone tissue engineering.

Sulfur Contents in Sulfonated Hyaluronic Acid Direct the Cardiovascular Cells Fate

Hyaluronic acid (HA) is recognized as a functional carbohydrate polymer applied for the surface modification of cardiovascular implanted materials due to its molecular weight (MW) dependent cellular regulation. However, due to the enzyme digestion of hyaluronidase on HA in vivo, the stability of HA MW needs to be further improved. It has been reported that the stability of HA MW can be improved by sulfonation. In this study, sulfonated hyaluronic acids (S-HA) with sulfur content of 2.06, 3.69, 7.10, 8.98, and 9.71 were prepared through different sulfuric acid treatment procedures. Cell tests showed that S-HA with higher sulfur content played a significant role in promoting the proliferation and migration of endothelial cells and regulating smooth muscle cells to the physiological phenotype. In addition, it was also proved to inhibit the inflammatory macrophages adhesion/activation. Our data indicates that S-HA may be a better carbohydrate polymer for potential application of cardiovascular biomaterials.

Design of Novel Perovskite-Based Polymeric Poly(l-Lactide-Co-Glycolide) Nanofibers with Anti-Microbial Properties for Tissue Engineering

There is a growing need for anti-microbial materials in several biomedical application areas, such are hernia, skin grafts as well as gynecological products, owing to the complications caused by infection due to surgical biomaterials. The anti-microbial effects of silver in the form of nanoparticles, although effective, can be toxic to surrounding cells. In this study, we report, for the first time, a novel biomedical application of Ag_0.3Na_1.7La₂Ti₃O₁₀-layered perovskite particles, blended with poly(L-lactide-co-glycolide) (PLGA), aimed at designing anti-microbial and tissue engineering scaffolds. The perovskite was incorporated in three concentrations of 1, 5, 10 and 15 w/w% and electrospun using dimethylformamide (DMF) and chloroform. The morphology of the resultant nanofibers revealed fiber diameters in the range of 408 to 610 nm by scanning electron microscopy. Mechanical properties of perovskite-based nanofibers also matched similar mechanical properties to human skin. We observed impressive anti-microbial activity, against Gram-negative, Gram-positive bacteria and even fungi, to Ag_0.3Na_1.7La₂Ti₃O₁₀ in powder as well as nanofiber-incorporated forms. Furthermore, cytotoxicity assay and immunocytochemistry revealed that perovskite-based nanofibers promoted the proliferation of human dermal fibroblasts whist maintaining normal cellular protein expression. Our study shows that perovskite-nanofibers have potential as scaffolds for biomedical applications with anti-microbial needs.

Bilirubin detoxification using different phytomaterials: characterization and in vitro studies

BACKGROUND

Activated carbon (AC) is a common adsorbent that is used in both artificial and bioartificial liver devices.

METHODS

Three natural materials - date pits of Phoenix dactylifera (fruit), Simmondsia chinensis (jojoba) seeds, and Scenedesmus spp. (microalgae) - were used in the present investigation as precursors for the synthesis of AC using physical activation. The chemical structures and morphology of AC were analyzed. Then, AC's bilirubin adsorption capacity and its cytotoxicity on normal liver (THLE2) and liver cancer (HepG2) cells were characterized.

RESULTS

Compared with the other raw materials examined, date-pit AC was highly selective and showed the most effective capacity of bilirubin adsorption, as judged by isotherm-modeling analysis. MTT in vitro analysis indicated that date-pit AC had the least effect on the viability of both THLE2 and HepG2 cells compared to jojoba seeds and microalgae. All three biomaterials under investigation were used, along with collagen and Matrigel, to grow cells in 3D culture. Fluorescent microscopy confirmed date-pit AC as the best to preserve liver cell integrity.

CONCLUSION

The findings of this study introduce date-pit-based AC as a novel alternative biomaterial for the removal of protein-bound toxins in bioartificial liver devices.