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Background: It is reported that long non-coding RNA nuclear paraspeckle assembly transcript 1 (LncRNA NEAT1) is involved in the occurrence and development of various cancers. However, the detailed biological function and mechanism of LncRNA NEAT1 in retinoblastoma are still unclear. So we will explore the biological function and possible mechanism of LncRNA NEAT1 in retinoblastoma., Materials and Methods: Quantitative real-time PCR (qRT-PCR) was used to detect LncRNA NEAT1 in retinoblastoma tissues and cell lines. Cell counting kit 8, Transwell and flow cytometry were applied to explore cell proliferation, invasion and apoptosis. The target miRNAs (miR) of LncRNA NEAT1 and miR and downstream target genes were predicted using Starbase3.0 software and confirmed by double luciferase reporting test and RNA binding protein immunoprecipitation (RIP). Western Blot was applied to explore ROCK1 in cells, and tumor allogeneic experiment was applied to study the role of LncRNA NEAT1 on tumor growth., Results: It was found that LncRNA NEAT1 was up-regulated in retinoblastoma tissues, cells and serum, and the prognosis of patients with high expression of LNC RNA NEAT 1 was poor. Functional analysis showed that knocking down LncRNA NEAT1 could weaken proliferation and invasion, and accelerate apoptosis. Tumor allogeneic experiment showed that sh-NEAT1 injection can inhibit tumor growth. In addition, LncRNA NEAT1 inhibited proliferation and invasion, and promoted apoptosis through miR-148b-3p/ROCK1 axis., Conclusion: LncRNA NEAT1 can mediate miR-148b-3p/ROCK1 axis to weaken the proliferation and invasion of retinoblastoma., Competing Interests: The authors report no conflicts of interest for this work., (© 2021 Lu et al.)

Objectives: Osteosarcoma (OS) is a type of bone malignancy. This study attempted to explore the effect of long non-coding RNA TTN-AS1 (TTN-AS1) on OS and to determine its molecular mechanisms., Methods: The expression of TTN-AS1, microRNA-16-1-3p (miR-16-1-3p), and transcription factor activating enhancer binding protein 4 (TFAP4) in OS was assessed using qRT-PCR. The OS cell proliferation, migration, and invasion were measured using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), wound-healing, and transwell assays. N-cadherin and MMP-2 protein level was determined with western blot. Interactions between TTN-AS1 and miR-16-1-3p or TFAP4 and miR-16-1-3p were confirmed using the dual-luciferase reporter assay. Additionally, an OS xenograft tumor model was constructed to assess the effect of TTN-AS1 on tumor growth., Results: TTN-AS1 and TFAP4 expression was increased in OS, while miR-16-1-3p expression was decreased. TTN-AS1 silencing restrained OS cell proliferation, migration, invasion, N-cadherin and MMP-2 protein expression, and hindered tumor growth. MiR-16-1-3p overexpression retarded the malignant behavior of OS cells. TTN-AS1 played a carcinostatic role by down-regulating miR-16-1-3p in the OS cells. Moreover, miR-16-1-3p inhibition or TFAP4 elevation weakened the suppressive effect of TTN-AS1 silencing on OS cell tumor progression., Conclusion: TTN-AS1 promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of OS cells via mediating the miR-16-1-3p/TFAP4 axis. TTN-AS1 may be a critical target for improving OS., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Meng, Zhang, Chen, Wang, Zhang and Liu.)

Objective: To investigate the effect of bilateral superior cervical sympathetic ganglion occlusion (SCG) on aortic dissection and its possible mechanism., Methods: Forty-five SD rats were randomly divided into three groups with 15 in each:blank control group, sham operation group and SCG group. β-aminopropione (666 mg·kg -1 ·d -1 ) was given by subcutaneous injection for 4 weeks to establish the aortic dissection model. Rats in SCG group were given SCG before the injection of β-aminopropione. Blood pressure and heart rate of the rats were monitored using noninvasive tail artery blood pressure measuring instrument; sympathetic activity was monitored using drug block method; the structure of aortic wall was observed using HE staining; collagen fibers in aortic wall was observed using Sirius red staining; protein expression of Apelin was detected by immunohistochemistry; and the protein expression of matrix metalloproteinase (MMP)-2, 9 was detected by Western blotting., Results: During the experiment, the body mass of the sham operation group and SCG group was smaller than that of the blank control group (all P <0.05), and the body mass of the SCG group was larger than that of the sham operation group (all P <0.05). The heart rate and sympathetic activity of the sham operation group were higher than those of the blank control group (all P <0.05), while the SCG group were lower (all P <0.05). Compared with the blank control group, the aortic wall in the sham operation group was thickening, while that in the SCG group was improved. A large number of collagen-1 in the aortic wall of the blank control group was stained brown by Sirius red, which was lighter in SCG group, and the staining in the sham operation group was the lightest. Compared with the blank control group, the expression of Apelin, MMP-2 and MMP-9 protein in the sham operation group increased (all P <0.05), while those in the SCG group decreased (all P <0.05)., Conclusions: SCG can effectively reduce the incidence and mortality of aortic dissection in rats, which may be related to the inhibition of sympathetic activity and the decrease of collagen-1, Apelin, MMP-2 and MMP-9 expression.

Background: Pancreatic cancer (PaC) is one of the deadliest types of tumor, and it is regarded as a fatal disease, with a 5-year survival rate less than 10%. Most clinical diagnoses for PaC are made at an advanced stage because of the insidious onset of the disease, which leads to an extremely poor prognosis., Recent Findings: The relationship between diabetes mellitus (DM) and PaC has been established by several decades of research, and the prevalence of DM in patients with PaC has been reported to be 40%, with half of the patients having developed new-onset DM within 2 years or less. Increasing evidence suggests that new-onset DM is associated with a high prevalence of PaC, and PaC resection ameliorates DM. Therefore, screening for PaC may be needed in patients with newly developed DM., Purpose: The objective of this review was to present our current understanding of biomarkers for PaC-associated new-onset DM (PCAND), to offer a perspective on the prospects and problems of using this strategy for early screening to differentiate PCAND from new-onset type 2 DM not associated with PaC and to suggest candidate biomarkers to use for PaC screening in patients with new-onset DM. Finding sensitive and specific biomarkers to manage these patients constitutes a challenge for the research community and for public health policies., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

In lumbar interbody fusion, a porous additive manufactured (AM) cage can provide more desirable stiffness, and may be beneficial to bone ingrowth. The biomechanical influence of porous cages on stability, subsidence, and facet contact force has not been fully described. The aim of this study was to verify biomechanical effects of porous cages. A surgical finite element (FE) model of transforaminal lumbar interbody fusion (TLIF) was constructed. Partially porous (PP) cages and fully porous (FP) cages were applied. Mechanical tests were performed to obtain the mechanical parameters of porous materials. The porous cages were compared to solid titanium (TI) cage and solid PEEK cage. Four motion modes were simulated. Range of motion (ROM), cage stress, endplate stress, and facet joint force (FJF) were compared. After interbody fusion, ROM decreased by more than 90% in flexion, bending and rotation. Compared with TI and PP cages, PEEK and FP cages substantially reduced the maximum stresses in cage and endplate in all motion modes. Compared with PEEK cages, the stresses in cage and endplate for FP cages decreased, whereas the ROM increased. Compared among three FP cages, the stresses in cage and endplate decreased with increasing porosity, whereas ROM increased with increasing porosity. FJF for various cages was substantially reduced compared to the intact model in all motion modes except for flexion. In summary, fully porous cages with a porosity of between 65% and 80% may offer an alternative to solid PEEK cages in TLIF., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Finite element models have been widely used to predict biomechanical parameters of the cervical spine. Previous studies investigated the influence of position of rotational centers of prostheses on cervical biomechanical parameters after 1-level total disc replacement. The purpose of this study was to explore the effects of axial position of rotational centers of prostheses on cervical biomechanics after 2-level total disc replacement., Methods: A validated finite element model of C3-C7 segments and 2 prostheses, including the rotational center located at the superior endplate (SE) and inferior endplate (IE), was developed. Four total disc replacement models were used: 1) IE inserted at C4-C5 disc space and IE inserted at C5-C6 disc space (IE-IE), 2) IE-SE, 3) SE-IE, and 4) SE-SE. All models were subjected to displacement control combined with a 50 N follower load to simulate flexion and extension motions in the sagittal plane. For each case, biomechanical parameters, including predicted moments, range of rotation at each level, facet joint stress, and von Mises stress on the ultra-high-molecular-weight polyethylene core of the prostheses, were calculated., Results: The SE-IE model resulted in significantly lower stress at the cartilage level during extension and at the ultra-high-molecular-weight polyethylene cores when compared with the SE-SE construct and did not generate hypermotion at the C4-C5 level compared with the IE-SE and IE-IE constructs., Conclusions: Based on the present analysis, the SE-IE construct is recommended for treating cervical disease at the C4-C6 level. This study may provide a useful model to inform clinical operations., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Based on the application of finite element analysis in spine biomechanics,the research progress of finite element method applied in lumbar spine mechanics is reviewed and the prospect is forecasted.The related works,including lumbar ontology modeling,clinical application research,and occupational injury and protection,are summarized.The main research areas of finite element method are as follows:new accurate modeling process,the optimized simulation method,diversified clinical effect evaluation,and the clinical application of artificial lumbar disc.According to the recent research progress,the application prospects of finite element method,such as automation and individuation of modeling process,evaluation and analysis of new operation methods and simulation of mechanical damage and dynamic response,are discussed.The purpose of this paper is to provide the theoretical reference and practical guidance for the clinical lumbar problems by reviewing the application of finite element method in the field of the lumbar spine biomechanics.

A diazulenylmethane dialdehyde reacted with dipyrrylmethanes in the presence of HCl or HBr, followed by oxidation with FeCl(3), to give aromatic adj-diazuliporphyrins. The free base structures must exist as mesoionic species, although these porphyrinoids were isolated as salts of the monoprotonated macrocycles. Reaction with Pd(OAc)(2) gave an unprecedented zwitterionic palladium(II) complex that was characterized by X-ray crystallography.