Preparation and characterization of scutellarin loaded on ultradeformable nano-liposomes scutellarin EDTMP (S-UNL-E) and in vitro study of its osteogenesis.

The present research aimed to elucidate a convenient, safe and economic approach to induce the growth of endogenous bone tissue and bone regeneration. S-UNL-E was prepared using reverse-phase evaporation, and scutellarin encapsulation was subsequently compared. Meanwhile, the optimal preparation scheme was developed using an orthogonal method, and the particle size was determined using laser light scattering. In osteoblasts cultured in vitro, methyl thiazolyl tetrazolium (MTT), alkaline phosphatase (ALP) staining and alizarin red staining were used to detect the osteogenic effects of S-UNL-E. The results indicated that the optimal process conditions for S-UNL-E included mass ratios of phospholipid-cholesterol, phospholipid-breviscapine, phospholipid-sodium cholate, and phospholipid-stearamide were 2:1, 15:1, 7:1 and 7:1, respectively, and the mass of ethylenediamine tetramethylphosphonic acid (EDTMP) was 30 mg. The average particle size of S-UNL-E was 156.67 ± 1.76 nm, and Zeta potential was -28.77 ± 0.66 mv. S-UNL-E substantially increased the expression of ALP osteoblasts, elevated the content of osteocalcin protein and promoted the formation of mineralized nodules. Cells in the S-UNL-E group were densely distributed with integrated cell structure, and the actin filaments were clear and obvious. The findings demonstrated that S-UNL-E greatly promoted the differentiation and maturation of osteoblasts, and S-UNL-E (2.5 × 108) produced the most favorable effect in differentiation promotion. In conclusion, the present study successfully constructed an S-UNL-E material characterized by high encapsulation and high stability, which could effectively promote osteogenic differentiation and bone formation.

[The biological safety evaluation of a new developed silicone rubber for inflatable silastic prosthesis].

OBJECTIVE: The biological safety of a new developed silicone rubber for inflatable silastic prosthesis (SRISP) was evaluated. METHODS: Following the GB/T 16886.10-2005 standard, YY/T 0127.13-2009 standard, and GB/T 16886.11- 2011 standard, samples were prepared and tested by animal experiments, such as guinea pig maximization test, oral mucous membrane irritation test, and short-term systemic toxicity test (oral route). RESULTS: No obvious erythema and edema in the guinea pig abdominal skin were observed after 24, 48, and 72 h of stimulating touch, thus indicating that SRISP does not cause potential skin sensitivity. No local response to SRISP was found, and the visual observation and pathological findings of oral mucosa were normal and similar to that of the control group. Therefore, SRISP had no irritation response to oral mucosa. No clinical signs of toxicity were observed in rats, and no significant differences in weight and weight relative growth rate between extract group and blank control group (P > 0.05) were found. Thus, SRISP had no short-term systemic toxicity. CONCLUSION: These results indicated that SRISP met the requirement of biomedical materials and had good bio- security.

The biological safety evaluation of a new developed silicone rubber for inflatable silastic prosthesis / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The biological safety of a new developed silicone rubber for inflatable silastic prosthesis (SRISP) was evaluated.</p><p><b>METHODS</b>Following the GB/T 16886.10-2005 standard, YY/T 0127.13-2009 standard, and GB/T 16886.11- 2011 standard, samples were prepared and tested by animal experiments, such as guinea pig maximization test, oral mucous membrane irritation test, and short-term systemic toxicity test (oral route).</p><p><b>RESULTS</b>No obvious erythema and edema in the guinea pig abdominal skin were observed after 24, 48, and 72 h of stimulating touch, thus indicating that SRISP does not cause potential skin sensitivity. No local response to SRISP was found, and the visual observation and pathological findings of oral mucosa were normal and similar to that of the control group. Therefore, SRISP had no irritation response to oral mucosa. No clinical signs of toxicity were observed in rats, and no significant differences in weight and weight relative growth rate between extract group and blank control group (P > 0.05) were found. Thus, SRISP had no short-term systemic toxicity.</p><p><b>CONCLUSION</b>These results indicated that SRISP met the requirement of biomedical materials and had good bio- security.</p>

Cytotoxicity of a new type silicone rubber for maxillofacial prosthesis: an in vitro evaluation / 生物医学工程学杂志

This study evaluated the cytotoxicity of a new type silicone rubber for maxillofacial prosthesis, which was developed by the present authors. According to the GB/T16886. 5- 2003, the samples were prepared and tested with cell counting kit-8 (CCK-8) assay, the relative growth rate (RGR) was calculated, and morphology of L929 cells were observed by scanning electron microscope and phase contrast microscope. The results showed that RGR of L929 cells were 91.65% (24 h), 87.03% (48 h), 87.30% (72 h), respectively, and the level of cytotoxicity was grade 1. The L929 cells showed typical fusiform shape and their morphology did not changed significantly after 24 h, 48 h and 72 h. These data indicated that the newly-developed silicone rubber material, as a maxillofacial prosthesis material, should be a safe biomaterial.