A novel gene recombinant collagen hemostatic sponge with excellent biocompatibility and hemostatic effect.

Effect and biosafety are the most noteworthy aspect of the hemostatic materials for trauma treatment. In this work, we evaluated the biocompatibility and hemostatic effect of a novel recombinant collagen hemostatic sponge according to ISO 10993. In addition, the interaction between the recombinant collagen hemostatic sponge and blood cells was observed by scanning electron microscopy, moreover, the hemostatic effect was evaluated by blood clotting assay in vitro and liver hemorrhage models in vivo. As the results, the novel recombinant collagen hemostatic sponge enables to be biodegradable completely in vivo, without stimulation, sensitization, acute toxicity, hematolysis or obvious immune rejection. The procoagulant effect of recombinant hemostatic sponge in vitro is significantly more excellent than that of natural collagen sponge due to the more promotive capacity of blood cell adhesion. Meanwhile, the liver hemorrhage models showed that the hemostatic time of recombinant collagen sponge was 19.33 ± 4.64 s, which was significantly better than that of natural collagen sponge (hemostatic time 31.62 ± 5.63 s). Therefore, the novel recombinant collagen hemostatic sponge with satisfactory biocompatibility and significant hemostatic effect can be performed as a potential novel type of clinical hemostatic products for research and development.

Assessment of biological properties of recombinant collagen-hyaluronic acid composite scaffolds.

OBJECTIVE: Recombinant collagen (rCOL)-hyaluronic acid (HA) composite scaffolds were prepared to thoroughly investigate their biological properties. METHODS: The rCOL and HA composite scaffolds were formulated via lyophilization. The scaffolds were characterized for various materials properties, including porosity, surface modification, and degradation rates. Biological properties such as in vitro cytotoxicity, cell adhesion, proliferation and migration effects were also evaluated. RESULTS: The water absorption, mechanical strength, degradation resistance and thermal stability of the prepared rCOL-HA composites were improved over that of the control studied. Scanning electron microscopy (SEM) revealed that the composites formed a three-dimensional network structure with uniform pore distribution. The cytotoxicity of the composites was minimal (grade I) and the material showed strong adhesion and proliferation effects when grown with mouse fibroblasts, particularly the composite material of rCOL (5% HA) group (P < 0.05). CONCLUSION: The rCOL-HA composite prepared via lyophilization after cross-linking is characterized by high porosity, high water absorption, and good interaction between the material and cells, as well as good biodegradability. Compared with rCOL materials, rCOL-HA has increased mechanical strength, water absorption and thermal stability. The biocompatibility and fibroblast proliferation of rCOL-HA have excellent biological performance, providing a new material for wound healing applications.

[Role and mechanism of cAMP/Ca 2+ signal pathway in differentiation of bone marrow mesenchymal stem cells into neuronal cells induced by salidroside].

To investigate the mechanism of cAMP/Ca 2+ signaling pathway inducing bone marrow mesenchymal stem cells to differentiate into neuronal cells, we cultured the bone marrow mesenchymal stem cells D1 cells in the present study. D1 cells were divided into two groups: control group and salidroside inducing groups. Control group was cultured with complete culture solution D/F12, while salidroside inducing groups were induced with 100 mg·L -1 salidroside for different time periods (24, 48 and 72 hours). PCR-array assay was used to detect expression of 84 calcium related mRNA, and significantly different genes were chosen to analyse. As a result, there were 4 significantly upregulated mRNAs inclu-ding DNA damage-inducible transcript 3 (Ddit3), heat shock protein 5 (Hspa5), protein phosphatase 1 regulatory subunit (Ppp1r15a) and prostaglandin-endoperoxide synthase 2 (Ptgs-2), and 4 significantly downregulated mRNAs including glucagon (Gcg), interleukin 2 (Il2), tumor necrosis factor (Tnf) and somatostatin (Sst) in the cAMP/Ca 2+ signaling pathway. They probably had an effect on the process of salidroside induced D1 cells differentiating into neuronal cells.