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Demineralized bone matrix (DBM) is a natural and collagen-based allogeneic bone graft material with good bioactivity and biocompatibility. However, there are conflicting reports on the efficiency of this product owning to the relevant factors, especially, the particle size of DBM. In the current study, osteoblasts were seeded onto DBM with diverse particle sizes of 0.6-1.0 mm, 2.2-2.6 mm, 3.8-4.2 mm and 5.4-5.8 mm, and then the cell adhesion, proliferation, differentiation and apoptosis were analyzed to evaluate the effects of particle sizes on bioactivity and biocompatibility of DBM. It could be identified that particle size had a significant influence on the surface roughness and the collagen structure of DBM. In-vitro cytological assays had confirmed that DBM with all particle sizes had good cytocompatibility, which was beneficial for cell survival. What's more, DBM with a smaller particle size had a better biological activity and could promote cell proliferation and differentiation. We hope that researchers could choose to apply DBM with particle size of 0.6-1.0 mm for further intensive study, from which researchers will acquire more comparable and reliable conclusions for different study purposes.

Purpose. Osteosarcoma (Os) is the most frequent malignant tumor of the bone in the pediatric age group, and accumulating evidences show that lncRNAs play a key role in the development of Os. Thus, we investigated the role of RBM5-AS1 and its molecular mechanism. Methods. The expression of RBM5-AS1 in Os tissues and cell lines was detected by real-time polymerase chain reaction (QPCR). The effect of RBM5-AS1 on the proliferation of Os cells was detected using CCK8 assays and flow cytometry. The effect of RBM5-AS1 on the migration and invasion of Os cells was detected by transwell assays. And we performed QPCR and western blotting assays to investigate the relationship between RBM5-AS1 and RBM5. Finally, western blotting assays were performed to explore the mechanism of RBM5. Results. LncRNA RBM5-AS1 was overexpressed in the Os tissues and cell lines. And lncRNA RBM5-AS1 promoted Os cell proliferation, migration, and invasion in vitro and tumor growth in vivo. LncRNA RBM5-AS1 targets RBM5 in Os cells. Conclusion. To sum up, the results showed that lncRNA RBM5-AS1 promotes cell proliferation, migration, and invasion in Os.

In this study, we investigated the effects of Angiotensin II (Ang II) on insulin-resistant endothelial cells. High glucose and insulin at series of concentrations were used to induce IR in Human Umbilical Vein Endothelial Cells (HUVECs). Successful IR induction was confirmed according to glucose consumption and glycogen content levels. Cell morphology was observed under a microscope. Expression levels of Ang II and Calreticulin (CRT) were measured by ELISA, qRT-PCR and Western blot as appropriate. Cell viability and apoptosis were measured by CCK-8 assay and flow cytometry, respectively. HUVECs with IR were exposed to Ang II at series of concentrations, and then the cell viability, apoptosis and CRT were detected. Rescue assays were performed by transfection of siCRT or overexpression of CRT with or without Ang II stimulation into the HUVECs with IR. Expressions of cell apoptosis-related proteins Bcl-2 and Bax were measured by qRT-PCR and Western blot. Glucose (33.3 mmol/L) and insulin (4 µmol/L) induced significantly strong IR to the HUVECs, with a pathological appearance. Levels of Agn II and CRT were both up-regulated by IR. Cell viability of HUVECs was slightly reduced after IR induction for 2 h, and cell apoptosis rate was increased. In addition, Ang II (10

Osteosarcoma (OS) is the most common primary malignant bone tumor, notorious for its metastasis. We have recently shown that shikonin, an effective constituent extracted from Chinese medicinal herb, induces necroptosis in OS cells. Nevertheless, the effects of low-dose shikonin on the invasiveness of OS cells are unknown. Here, we showed that shikonin dose-dependently decreased OS cell invasiveness in both scratch wound healing assay and transwell cell migration assay. Moreover, the direct target of shikonin on cell invasiveness was found to be matrix metalloproteinase (MMP)-13. Further, the inhibitory effects of shikonin on cell invasiveness were completely abolished in MMP13-overexpressing OS cells. Together, these data suggest that shikonin may suppress OS invasiveness through MMP13 suppression. Thus, our data highlight a previous unappreciated role for shikonin in suppressing OS cell metastasis.

Patient-specific instrumentation (PSI) was designed to improve the accuracy of preoperative planning and postoperative prosthesis positioning in total knee arthroplasty (TKA). However, better understanding needs to be achieved due to the subtle nature of the PSI systems. In this study, 3D printing technique based on the image data of computed tomography (CT) has been utilized for optimal controlling of the surgical parameters. Two groups of TKA cases have been randomly selected as PSI group and control group with no significant difference of age and sex (p > 0.05). The PSI group is treated with 3D printed cutting guides whereas the control group is treated with conventional instrumentation (CI). By evaluating the proximal osteotomy amount, distal osteotomy amount, valgus angle, external rotation angle, and tibial posterior slope angle of patients, it can be found that the preoperative quantitative assessment and intraoperative changes can be controlled with PSI whereas CI is relied on experience. In terms of postoperative parameters, such as hip-knee-ankle (HKA), frontal femoral component (FFC), frontal tibial component (FTC), and lateral tibial component (LTC) angles, there is a significant improvement in achieving the desired implant position (p

The regenerative potential of alginate-chitosan composite in bone and cartilage tissue has been well documented, but its potential utility in cardiac tissue engineering has remained unknown. This study sought to determine whether early intramyocardial injection of alginate-chitosan could prevent left ventricular (LV) remodeling after myocardial infarction (MI), leading to a more favorable course of tissue restoration. In a rat model of acute MI, local injection of alginate-chitosan hydrogel into the peri-infarct zone preserved scar thickness, attenuated infarct expansion, and reduced scar fibrosis after 8 weeks, concomitantly with promoting increased angiogenesis and greater recruitment of endogenous repair at the infarct zone. Furthermore, this treatment prevented cell apoptosis, induced cardiomyocyte cell cycle re-entry. The cardiac function of the control-injected animals deteriorated over the 8-week course, while that of the hydrogel-injected animals did not.In addition, the hydrogel did not exacerbate inflammation in the heart. Intramyocardial injection of alginate-chitosan hydrogel represents a useful strategy to treat MI. It demonstrated marked therapeutic efficacies on various tissue levels after extensive MI, as well as potential to induce endogenous cardiomyocyte proliferation and recruit cardiac stem cells.

Pre B cell leukemia homeobox 2 (PBX2), a member of PBX family, acts as a co-factor of homeobox proteins to regulate proliferation and differentiation of tumor cells. Our recent study revealed prognostic significance of PBX2 expression in non-small cell lung carcinoma. The significance of PBX2 expression was examined in cases with gastric cancer (GC) and esophageal squamous cell carcinoma (ESCC), and the role of PBX2 in tumor behavior was evaluated in GC and ESCC cell lines of knocked-down PBX2 expression. Expression level of PBX2 was immunohistochemically examined in 94 patients of GC and 64 patients of ESCC. Staining intensity for PBX2 was categorized as equal to or stronger (level 1) and weaker (level 2) than that of endothelial cells. Cases with level 1 expression in more than 20% of tumor were defined as high and others low expression. Patients with low PBX2 expression showed a better prognosis than those with high expression in both GC and ESCC. Multivariate analysis revealed PBX2 expression to be an independent prognosticator for both GC and ESCC. Knocked-down expression of PBX2 in GC and ESCC cell lines resulted in decrease of in vitro colony formation and in vivo tumorigenic activities, but proliferative and invasive activities did not change. Under serum depletion, apoptotic cell proportion was higher in PBX2 knocked-down cells than in control cells. The knock-down of PBX2 reduced Bcl-2 expression. Taken together, the high expression level of PBX2 was an independent negative prognosticator for both GC and ESCC, and PBX2 might promote tumor growth through suppression of apoptosis.