Recent advances in nanomaterials for the treatment of spinal cord injury.

Spinal cord injuries (SCIs) are devastating. In SCIs, a powerful traumatic force impacting the spinal cord results in the permanent loss of nerve function below the injury level, leaving the patient paralyzed and wheelchair-bound for the remainder of his/her life. Unfortunately, clinical treatment that depends on surgical decompression appears to be unable to handle damaged nerves, and high-dose methylprednisolone-based therapy is also associated with problems, such as infection, gastrointestinal bleeding, femoral head necrosis, obesity, and hyperglycemia. Nanomaterials have opened new avenues for SCI treatment. Among them, performance-based nanomaterials derived from a variety of materials facilitate improvements in the microenvironment of traumatic injury and, in some cases, promote neuron regeneration. Nanoparticulate drug delivery systems enable the optimization of drug effects and drug bioavailability, thus contributing to the development of novel treatments. The improved efficiency and accuracy of gene delivery will also benefit the exploration of SCI mechanisms and the understanding of key genes and signaling pathways. Herein, we reviewed different types of nanomaterials applied to the treatment of SCI and summarized their functions and advantages to provide new perspectives for future clinical therapies.

Animal Models for Postoperative Implant-Related Spinal Infection.

Postoperative infections following implant-related spinal surgery are severe and disastrous complications for both orthopaedic surgeons and patients worldwide. They can cause neurological damage, disability, and death. To better understand the mechanism of these destructive complications and intervene in the process, further research is needed. Therefore, there is an urgent need for efficient, accurate, and easily available animal models to study the pathogenesis of spinal infections and develop new and effective anti-bacterial methods. In this paper, we provide a general review of the commonly used animal models of postoperative implant-related spinal infections, describe their advantages and disadvantages, and highlight the significance of correctly choosing the model according to the infection aspect under investigation. These models are valuable tools contributing to the better understanding of postoperative spinal infections and will continue to facilitate the invention of novel preventative and treatment strategies for patients with postoperative spinal infections. However, although they are valid and reproducible in some respects, the current animal models present certain limitations. Future ideal spinal infection animal models may assess the bacterial load of the same animal in real-time in vivo, and better mimic the human anatomy as well as surgical techniques. Strains other than Staphylococcus aureus account for a large proportion of postoperative spinal infections, and thus, the establishment of models to evaluate other types of microbial infections is expected in the future. Furthermore, novel transgenic models established on advancements in genome editing are also likely to be developed in the future.

Finite Element Analysis of a New Type of Spinal Protection Device for the Prevention and Treatment of Osteoporotic Vertebral Compression Fractures.

OBJECTIVE: To study the effectiveness of a new spinal protection device for preventing and treating osteoporotic vertebral compression fractures (OVCFs) by finite element analysis (FEA). METHODS: One healthy volunteer and one patient with 1-segment lumbar vertebral compression fractures were included in this experimental study. The DICOM files of two different lumbar spiral computed tomography (CT) scans were converted into STL files, and 3D finite element models of the lumbar spine were generated for normal and L1 vertebral fracture spines. A new type of spinal protection device was applied to reduce the stress on the anterior vertebral edge and direct the center of gravity posteriorly. The stress distribution characteristics of different finite element models of the lumbar spine were analyzed, revealing the characteristics of the stress distributed along the spine under the action of the new spinal protection device. RESULTS: Under normal conditions, the stress was mainly distributed in the middle and posterior columns of the spine. When the anterior border of the L1 vertebral body was fractured and collapsed, the stress distribution shifted toward the anterior column due to the center of gravity being directed forward. According to finite element analysis of the spine with the new protection device, the stress in the middle and posterior columns tended to increase, and that in the anterior column decreased. After the new type of spinal fixation device was applied, the stress at the L1 and L2 vertebral endplates decreased to a certain extent, especially that at the L1 vertebral body. The maximum stress on the L1 vertebral body decreased by 20% after the auxiliary device was applied. CONCLUSIONS: According to the FEA results, the new spinal protection device can effectively prevent and treat osteoporotic vertebral compression fractures (OVCFs), and can alter the stress distribution in the spine and reduce the stress in the anterior column of the vertebral body, especially in vertebral compression fractures.

Characterization of human induced pluripotent stem cells line JLUEYEi002-A from a 48 year old healthy male.

Peripheral blood was extracted from a 48-year old healthy male donor. Induced pluripotent stem cells (iPSC) were reprogrammed by sendai virus encoding Klf-4, c-Myc, Oct-4, and Sox-2. The iPSC line showed pluripotency, which was verified by immunofluorescence staining. The iPSC line showed normal karyotype, and could form embryoid bodies in vitro and differentiate into the 3 germ layers in vivo. This cell line can be served as healthy control for studying inherited disease.

Generation and characterization of human induced pluripotent stem cells line JLUEYEi001-A from a 45 year old female with Stickler syndrome.

Peripheral blood was extracted from a 45-year old female patient clinically diagnosed with Stickler syndrome harboring a heterozygous splicing mutation in COL2A1 (NM_033150, IVS22-1C>T). Induced pluripotent stem cells (iPSC) were reprogrammed by sendai virus encoding Klf-4, c-Myc, Oct-4, and Sox-2. The iPSC line showed pluripotency, which was verified by immunofluorescence staining. The iPSC line showed normal karyotype, and could form embryoid bodies in vitro and differentiate into the 3 germ layers in vivo. This in vitro cellular model can be used to study the pathogenesis underlying Stickler syndrome.

Long noncoding RNA HCG18 inhibits the differentiation of human bone marrow-derived mesenchymal stem cells in osteoporosis by targeting miR-30a-5p/NOTCH1 axis.

BACKGROUND: Recent studies have demonstrated that long non-coding RNAs (LncRNAs) can influence bone cell differentiation and formation. However, it is unclear whether lncRNA HCG18 is involved in osteoporosis (OP). This study was conducted to investigate the regulation of HCG18 in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). METHODS: BMSCs were isolated and cultured from mouse pathological models and osteoporosis patients. RT-qPCR was performed to detect the expression of HCG18 and miR-30a-5p in BMSCs. The interaction between HCG18 and miR-30a-5p was analyzed by dual luciferase assay and RNA pulldown assay. The interaction between miR-30a-5p and NOTCH1 3'-UTR was analyzed by dual luciferase assay. RT-qPCR and Western blotting were used to detect the expression of osteogenic genes Runx2, OCN and OPN. Hindlimb-unloaded (HU) mice model was established, and HCG18 was knocked down on bone-formation surfaces by using lentivirus mediated shRNA transfection. RESULTS: The expression of HCG18 was increased in BMSCs of OP patients, while the expression of miR-30a-5p was decreased. The expression of HCG18 and miR-30a-5p was negatively correlated in BMSCs. During the differentiation from BMSCs to osteoblasts, the expression of HCG18 was significantly downregulated, and the expression of miR-30a-5p was significantly upregulated. Overexpression of HCG18 was able to reverse the osteogenic-induced upregulation of miR-30a-5p expression, and knockdown of HCG18 further promoted the expression of miR-30a-5p. In addition, miR-30a-5p partially abolished the effect of HCG18 on osteogenic differentiation of BMSCs. NOTCH1 was a target protein of miR-30a-5p, and upregulation of NOTCH1 reversed the effect of miR-30a-5p on osteogenic differentiation of BMSCs. Furthermore, this study found that lentivirus mediated HCG18 knockdown on the bone-formation surfaces of hindlimb-unloaded (HU) mice partially alleviated unloading-induced bone loss CONCLUSIONS: HCG18 inhibited osteogenic differentiation of BMSCs induced by OP via the miR-30a-5p/NOTCH1 axis. HCG18 can be identified as a regulator of osteogenic differentiation of BMSCs.

Circular RNA PVT1 promotes metastasis via regulating of miR-526b/FOXC2 signals in OS cells.

As a class of covalently closed non-coding RNAs, circular RNAs (circRNAs) are key regulators in various malignancies including osteosarcoma (OS). In the present study, we found that circular RNA PVT1 (circPVT1) was up-regulated in OS and correlated with poor prognosis of patients with OS. Functionally, we showed that knockdown of circPVT1 suppressed OS cells metastasis. In addition, we found that (forkhead box C2) FOXC2 was a downstream gene in circPVT1-mediated metastasis in OS cells. We demonstrated that circPVT1 promoted OS cells metastasis via post-transcriptionally regulating of FOXC2. Furthermore, we revealed that microRNA 526b (miR-526b) was a key bridge which connected circPVT1 and FOXC2. We showed that miR-526b was down-regulated in OS tissue and cell lines. Through a transwell assay, we found that miR-526b suppressed OS cells metastasis by targeting of FOXC2. We also showed that miR-526b targeted circPVT1 via similar mircoRNA response elements (MREs) as it did for FOXC2. Finally, we proved that circPVT1 decoyed miR-526b to promote FOXC2-mediated metastasis in OS cells. In brief, our current study demonstrated that circPVT1, functioning as an oncogene, promotes OS cells metastasis via regulation of FOXC2 by acting as a ceRNA of miR-526b. CircPVT1/miR-526b/FOXC2 axis might be a novel target in molecular treatment of OS.

[Progress on clinical treatment of Kümmell's disease].

Kümmell's disease is a delayed complication of osteoporotic vertebral compression fracture (OVCF) . The disease can occur months or even years after the initial spinal injury. Unlike the common osteoporotic compression fracture, it develops slowly and causes intractable pain or neurological dysfunction due to intraspinal instability. So far, the pathogenesis of Kümmell's disease has not been completely clear, there is no standard treatment or single effective treatment for Kümmell's disease. The effect of conservative treatment is often not good. Minimally invasive treatment has become the main treatment for patients with Kümmell's disease due to its short operation time, small trauma and exact effect. However, there are complications such as leakage of bone cement and delayed displacement of bone cement. Moreover, minimally invasive treatment is not suitable for all types of Kümmell's disease patients. Patients with posterior cortical fracture and spinal cord compression need to be opened Radiotherapy, whether anterior or posterior, has the disadvantages of long operation time, large trauma and high treatment cost. This article reviews the progress in the treatment of Kümmell's disease to provide guidance for clinical treatment.

Development of human induced pluripotent stem cell (iPSC) line from a 60year old female patient with multiple schwannoma.

Peripheral blood was collected from a clinically diagnosed 60-year old female patient with multiple schwannoma. Peripheral blood mononuclear cells (PBMCs) were reprogrammed with the Yamanaka KMOS reprogramming factors using the Sendai-virus reprogramming system. The transgene-free iPSC line showed pluripotency verified by immunofluorescent staining for pluripotency markers, and the iPSC line was able to differentiate into the 3 germ layers in vivo. The iPSC line also showed normal karyotype. This in vitro cellular model will be useful for further pathological studies of multiple schwannoma.

Characterization of human induced pluripotent stem cell (iPSC) line from a 72year old male patient with later onset Alzheimer's disease.

Peripheral blood was collected from a clinically diagnosed 72-year old male patient with later onset Alzheimer's disease. Peripheral blood mononuclear cells (PBMCs) were reprogrammed with the Yamanaka KMOS reprogramming factors using the Sendai-virus reprogramming system. The transgene-free iPSC line showed pluripotency verified by immunofluorescent staining for pluripotency markers, and the iPSC line was able to differentiate into the 3 germ layers in vivo. The iPSC line also showed normal karyotype. This in vitro cellular model will be useful for studying the pathological mechanism of Alzheimer's disease.

Derivation of human induced pluripotent stem cell (iPSC) line from a 79year old sporadic male Parkinson's disease patient.

Peripheral blood was collected from a clinically diagnosed 79-year old male sporadic Parkinson's disease patient. Peripheral blood mononuclear cells (PBMCs) were reprogrammed with the Yamanaka KMOS reprogramming factors using the Sendai-virus reprogramming system. The transgene-free iPSC line showed pluripotency verified by immunofluorescent staining for pluripotency markers, and the iPSC line was able to differentiate into the 3 germ layers in vivo. The iPSC line also showed normal karyotype. This in vitro cellular model can be used to study the mechanism of sporadic Parkinson's disease and to test new drugs. Resource Table.

Generation of a human induced pluripotent stem cell (iPSC) line from a 64year old male patient with multiple schwannoma.

Peripheral blood was collected from a clinically diagnosed 64-year old male multiple schwannoma patient. Peripheral blood mononuclear cells (PBMCs) were reprogrammed with the Yamanaka KMOS reprogramming factors using the Sendai-virus reprogramming system. The transgene-free iPSC line showed pluripotency verified by immunofluorescent staining for pluripotency markers, and the iPSC line was able to differentiate into the 3 germ layers in vivo. The iPSC line also showed normal karyotype. This in vitro cellular model will be useful for further pathological studies of multiple schwannoma.

MicroRNA-342-3p Inhibits the Proliferation, Migration, and Invasion of Osteosarcoma Cells by Targeting Astrocyte-Elevated Gene-1 (AEG-1).

Recent studies suggest that microRNAs (miRNAs) are critical regulators in many types of cancer, including osteosarcoma. miR-342-3p has emerged as an important cancer-related miRNA in several types of cancers. However, the functional significance of miR-342-3p in osteosarcoma is unknown. The aims of this study were to investigate whether miR-342-3p is dysregulated in osteosarcoma and to explore the biological function of miR-342-3p in regulating cellular processes of osteosarcoma cells. We found that miR-342-3p expression was significantly decreased in osteosarcoma tissues and cell lines. Overexpression of miR-342-3p inhibits the proliferation, migration, and invasion of osteosarcoma cells. In contrast, the inhibition of miR-342-3p exhibited the opposite effect. Astrocyte-elevated gene-1 (AEG-1) was identified as one of the target genes of miR-342-3p in osteosarcoma cells by bioinformatics analysis, dual-luciferase reporter assay, real-time quantitative polymerase chain reaction, and Western blot analysis. Overexpression of miR-342-3p also inhibited the Wnt and nuclear factor κB signaling pathways. Moreover, overexpression of AEG-1 partially rescued the inhibitory effects of miR-342-3p mediated on the proliferation, migration, and invasion of osteosarcoma cells. Overall, our results show that miR-342-3p inhibits the proliferation, migration, and invasion of osteosarcoma cells through targeting AEG-1, suggesting a potential target for the development of miRNA-based therapy for osteosarcoma.