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Purpose: This research was conducted to assess the biocompatibility of the core-shell Fe 3 O 4 @ Au composite magnetic nanoparticles (MNPs), which have potential application in tumor hyperthermia. Methods: Fe 3 O 4 @Au composite MNPs with core-shell structure were synthesized by reduction of Au 3+ in the presence of Fe 3 O 4 -MNPs prepared by improved co-precipitation. Cytotoxicity assay, hemolysis test, micronucleus (MN) assay, and detection of acute toxicity in mice and beagle dogs were then carried out. Results:The result of cytotoxicity assay showed that the toxicity grade of this material on mouse fibroblast cell line (L-929) was classified as grade 1, which belongs to no cytotoxicity. Hemolysis rates showed 0.278%, 0.232%, and 0.197%, far less than 5%, after treatment with different concentrations of Fe 3 O 4 @Au composite MNPs. In the MN assay, there was no significant difference in MN formation rates between the experimental groups and negative control (P . 0.05), but there was a significant difference between the experimental groups and the positive control (P , 0.05). The median lethal dose of the Fe 3 O 4 @Au composite MNPs after intraperitoneal administration in mice was 8.39 g/kg, and the 95% confidence interval was 6.58-10.72 g/kg, suggesting that these nanoparticles have a wide safety margin. Acute toxicity testing in beagle dogs also showed no significant difference in body weight between the treatment groups at 1, 2, 3, and 4 weeks after liver injection and no behavioral changes. Furthermore, blood parameters, autopsy, and histopathological studies in the experimental group showed no significant difference compared with the control group. Conclusion:The results indicate that Fe 3 O 4 @Au composite MNPs appear to be highly biocompatible and safe nanoparticles that are suitable for further application in tumor hyperthermia.

Background: Tendinopathy is still a great challenge in clinical practice, and the role of platelet-rich plasma (PRP) is controversial. The influence of leukocytes on tendinopathy at an early stage has not been defined so far. Purpose: To compare the effects of leukocyte-rich PRP (Lr-PRP) and leukocyte-poor PRP (Lp-PRP) on Achilles tendinopathy when applied at an early stage. Study Design: Controlled laboratory study. Methods: A rabbit Achilles tendinopathy model was induced by a collagenase injection. A week later, treatments were applied randomly on local Achilles tendon lesions: (1) 200 μL of Lr-PRP (16 legs), (2) 200 μL of Lp-PRP (16 legs), and (3) 200 μL of saline (16 legs). At 3 and 6 weeks after the collagenase injection, outcomes were evaluated by histology, magnetic resonance imaging (MRI), real-time polymerase chain reaction analysis, immunohistochemistry, and transmission electron microscopy (TEM). Results: The Lr-PRP group had a lower T2 signal intensity ( P = .0377) and smaller diameter ( P = .0193) and cross-sectional area ( P = .0194) than the Lp-PRP group on MRI. Histologically, the Lr-PRP group had better scores than the Lp-PRP group ( P = .0284 and P = .0188, respectively). Compared with the Lp-PRP group, higher gene expression and more protein synthesis of collagen I ( P = .0160 and P = .0309, respectively) and CD163 ( P < .0001 and P = .0411, respectively) were found in the Lr-PRP group. Considering TEM and biomechanical testing, the Lr-PRP group demonstrated more mature collagen fibers ( P < .0001), a larger fiber diameter ( P = .0005), a higher failure load ( P = .00417), and higher tensile stress ( P < .0001) than the Lp-PRP group. Conclusion: Lr-PRP had more beneficial effects than Lp-PRP when delivered at an early stage during tendon repair. Clinical Relevance: Here, we showed that tendinopathy influenced the curative effects of PRP in vivo. An early-stage application of Lr-PRP had more benefits for the repair of tendinopathy than Lp-PRP in a rabbit model, which will supplement guidelines of PRP treatment on tendinopathy clinically.

Glioblastoma multiforme (GBM) is the most common and severe form of primary tumor in the central nervous system of adults which has poor prognosis and limited therapeutic options. Epidermal growth factor receptor (EGFR) inhibitor, such as gefitinib (brand name Iressa, ZD1839), has been approved as a targeted medicine for several types of tumor including glioblastoma multiforme. However, gefitinib exerted very limited effects on some glioblastoma multiforme patients after a period of treatment due to intrinsic and acquired drug resistance. β-Elemene, a natural plant drug extracted from Curcuma wenyujin, has shown promising anticancer effects against a broad spectrum of tumors. In the present study, we found that β-elemene could enhance the chemosensitivity of glioblastoma multiforme cells to gefitinib. The combination medication of β-elemene and gefitinib not only inhibited the survival and proliferation of glioblastoma multiforme cells via inhibition of EGFR signaling pathway but also induced more distinct apoptosis and autophagy in the glioblastoma multiforme cells than the gefitinib monotherapy. These results showed that β-elemene might be one potential adjuvant to enhance the effect of EGFR inhibitor and reduce the resistance of gefitinib in glioblastoma multiforme.

Metformin, an anti-diabetic drug commonly used for type 2 diabetes therapy, is associated with anti-angiogenic effects in conditions beyond diabetes. miR-21 has been reported to be involved in the process of angiogenesis. However, the precise regulatory mechanisms by which the metformin-induced endothelial suppression and its effects on miR-21-dependent pathways are still unclear. Bioinformatic analysis and identification of miR-21 and its targets and their effects on metformin-induced antiangiogenic activity were assessed using luciferase assays, quantitative real-time PCR, western blots, scratch assays, CCK-8 assays and tubule formation assays. In this study, miR-21 was strikingly downregulated by metformin in a time- and dose-dependent manner. miR-21 directly targeted the 3′-UTR of PTEN and SMAD7, and negatively regulated their expression. Overexpression of miR-21 abrogated the metformin-mediated inhibition of endothelial cells proliferation, migration, tubule formation and the TGF-β-induced AKT, SMAD- and ERK-dependent phosphorylations, and conversely, down-regulation of miR-21 aggravated metformin’s action and revealed significant promotion effects. Our study broadens our understanding of the regulatory mechanism of miR-21 mediating metformin-induced anti-angiogenic effects, providing important implications regarding the design of novel miRNA-based therapeutic strategies against angiogenesis.