Preparation and cytocompatibility evaluation for hydrosoluble phosphorous acid-derivatized cellulose as tissue engineering scaffold material.

Chemical modification of cellulose by phosphorylation enhances its bioactivity and provides new derivatives and materials with specific end uses. In the present study, cellulose derivatized with phosphorous acid was obtained using the reaction of microcrystalline cellulose with phosphorous acid-urea mixture, in molten state, in comparison with others methods that used different solvents and catalysts. Completely water soluble films with a substitution degree close to one were obtained and characterized by analytical and spectral analysis (FT-IR, (31)P NMR), contact angle, metallographic microscopy and atomic force microscopy (AFM). 31P NMR spectra of derivatized cellulose showed a signal at 2.58 ppm (assigned to P-O-C6) while the doublets at 4.99-5.29 and at 7.38 ppm were assigned to P-O-C2 and P-O-C3, respectively; thus, the formation of monosubstituted phosphorous acid esters of cellulose is advocated. Contact angle measurements showed that the work of adhesion is more important in water than in ethylene glycol, for the phosphorous acid derivatized cellulose. The cytocompatibility of this hydrosoluble derivatized cellulose was tested by direct contact and also by indirect assays on normal human dermal fibroblasts and on osteoblast-like cells (human osteosarcoma). Cell growth on phosphorylated cellulose pellicle and the results from viability assays had shown a good cytocompatibility and lack of toxicity. Phosphorous acid derivatized cellulose would offer a promising biomaterial, useful as scaffolds for new biopolymer composites, and subject for further development as an ionic crosslinker.

A systematic review of orbital apex syndrome of odontogenic origin: Proposed algorithm for treatment.

Orbital apex syndrome (OAS) can be a rare, but severe complication of an odontogenic infection and has high morbidity and mortality. Antibacterial drugs are typically an appropriate treatment choice, but the most severe cases are fungal in nature and pose a tough challenge to the clinician. The aim of this study was to determine the predisposing factors, specific aspects in its management and the appropriate treatment strategy in order to improve patient outcome. A systematic review was conducted using PubMed, PubMed Central, Web of Science, and Scopus up to February 2020, based on the associations between dental extraction or infections and OAS. Of 721 papers found, 18 articles were considered eligible and presented in total 21 cases (13 fungal and eight bacterial infections). The information was organized into a diagnostic and treatment algorithm which included data extracted both from the included cases and updated literature of treatment efficacy studies. Immunosuppression (uncontrolled diabetes mellitus and chemotherapy) was found as an important predisposing factor particularly for fungal infections. In these cases, we suggest that early simultaneous approaches, including aggressive surgical procedures and systemic administration of amphotericin B, result in a better outcome. In conclusion, medical intervention success depends on aggressive treatment and multidisciplinary teamwork.

In vitro evaluation of curcumin effects on breast adenocarcinoma 2D and 3D cell cultures.

UNLABELLED: Breast adenocarcinoma cell line MDA-MB-231, even if it expresses low levels of E-cadherin, still readily form multicellular aggregates of cells, namely spheroids. Curcumin is a diarylheptanoid antitumoral drug while it significantly inhibits cell migration, invasion, and colony formation in vitro and reduces tumor growth and liver metastasis in vivo. Curcumin photoactivation may enhance antiapoptotic role against cancer cells. AIM: To evaluate the effect of low curcumin concentrations, ranged from 1.9 to 15 µM, with and without photoactivation, using a manufactured 670 nm LED-matrix. A secondary aim was to evaluate the ideal method to produce easy-to-use tumor cell spheroids, comparing two low adherence plate supports. MATERIALS AND METHODS: Breast adenocarcinoma cell line MDA-MB-231 were cultured according to 2D monolayer and 3D spheroid models then submitted to normal and photoactivated curcumin in micromolar concentrations. MTT assay was used to evaluate cell viability following curcumin application on cells. On 2D cell cultures, curcumin inhibits cell tumor development and proliferation at concentrations of 15 µM, with a viability of 65.7% at 48 hours incubation time. A decreased viability up to 25% for a concentration of 15 µM was recorded following photoactivation and cytotoxic action on breast cancer tumor cell line continued at concentrations of 7.5 and 3.75 µM. Curcumin photoactivation increases pro-apoptotic effects in both 2D and 3D tumor cell culture models and also responsiveness to curcumin is slightly reduced in spheroid-like structures. Thus, 3D tumor cell culture systems appear to be the ideal environment for in vitro assays regarding anticancer drug effects on cell viability.