A facile turn-on chemiluminescence probe for sensitive imaging on aminopeptidase N activity.

Aminopeptidase N, as a target for drug discovery, shows marked relationships with many diseases, especially liver injury and cancer. Here, we explored a chemiluminescence (CL) probe for sensing APN by tethering the APN-specific substrate group to the ortho-acrylated phenoxy-dioxetane scaffold. In this way, two CL probes (APN-CL and BAPN-CL) were designed with noncapped leucine and butoxy-carbonyl capped leucine as the protecting group to preserve the chemiexcitation energy. The uncovered leucine was demonstrated to be essential for detection of APN activity by comparing the CL intensity of two CL probes. Probe APN-CL was turned on upon APN cleavage, resulting in a high chemiluminescent emission, whereas the chemiexcitation energy of probe BAPN-CL was still restrained even with the high-level APN. The result was further elucidated by molecular docking simulations. Probe APN-CL exhibited a fast response and high sensitivity with a detection limit of 0.068 U/L, and an excellent specificity for the discrimination of APN from biological ions, small molecules, and other proteases commonly found in living system. By virtue of good stability and cell viability, probe APN-CL imaged abnormal levels of APN in tumour cells and tumour-bearing mice. Moreover, this probe APN-CL could be easily used to evaluate APN inhibitors and APN levels in plasma samples from 20 patients. Overall, as a facile and cost-effective probe, APN-CL will be a promising alternative in the early diagnosis of pathologies and for cost-effective screening of inhibitors.

ZIP8 mediates the extracellular matrix degradation of nucleus pulposus cells via NF-κB signaling pathway.

The extracellular matrix (ECM) degradation of nucleus pulposus cells (NPCs) is mainly induced by metalloproteinases (MMPs). Zn2+ is an essential component of MMPs, but the effect of Zn2+ importers in controlling ECM metabolism remains unclear. The purpose of this research was to identify the involvement of Zn2+ importers in ECM degradation induced by inflammatory stimuli and excessive mechanical stressing. In this study, NPCs from Sprague-Dawley (SD) rats were separated and cultured. FluoZin-3 AM staining was applied to detect [Zn2+]i in NPCs treated with Interleukin-1ß (IL-1ß) or cyclic tensile strain (CTS) with a Flexcell Strain Unit. We found that intracellular Zn2+ concentration ([Zn2+]i) elevated dramatically, and ZIP8 is the predominant Zn2+ importer among all importers in senescent NPCs. The [Zn2+]i and MMP expression level both increased in IL-1ß and CTS treated NPCs. Furthermore, the expression of ZIP8 was also markedly increased. However, knockdown of ZIP8 with siRNA alleviated ECM degradation induced by inflammatory stimuli and CTS. Both stimuli activated NF-κB signaling pathway, and knockdown of ZIP8 effectively inhibited NF-κB signaling pathway activation. In conclusion, knockdown of ZIP8 can alleviate NPCs' ECM degradation caused by inflammatory stimuli and excessive mechanical stressing.

A prospective randomized trial comparing anterior cervical discectomy and fusion versus plate-only open-door laminoplasty for the treatment of spinal stenosis in degenerative diseases.

OBJECTIVE: For three or more involved cervical levels, there is a debate over which approach yields the best outcomes for the treatment of multilevel cervical degenerative disease. Our objective is to compare the radiological and clinical outcomes of two treatments for multilevel cervical degenerative disease: anterior cervical discectomy and fusion (ACDF) versus plate-only open-door laminoplasty (laminoplasty). METHODS: Patients were randomized on a 1:1 randomization schedule with 17 patients in the ACDF group and 17 patients in the laminoplasty group. Clinical outcomes were assessed by a visual analog scale (VAS), Japanese Orthopedic Association (JOA) scores, operative time, blood loss, rates of complications, drainage volume, discharge days after surgery, and complications. The cervical spine curvature index (CI) and range of motion (ROM) were assessed with radiographs. RESULTS: The mean VAS score, the mean JOA score, and the rate of complications did not differ significantly between groups. The laminoplasty group had greater blood loss, a longer operative time, more drainage volume, and a longer hospital stay than the ACDF group. There were no significant differences in the CI and ROM between the two groups at baseline and at each follow-up time point. ROM in both groups decreased significantly after surgery. CONCLUSIONS: Both ACDF and laminoplasty are effective and safe treatments for multilevel cervical degenerative disease. ACDF causes fewer traumas than laminoplasty.

Surgical Landmark of Mandible Angle in the Identification of Cervical Spinal Level.

Mandible angle is considered to be a consistently palpable external landmark for the identification of cervical spinal level by a radiographic study. But this anatomical study aimed to determine the positional relationship between mandible angle and cervical spinal level in cadavers. In this study, the cervical spine of 10 adult cadavers with intact head and neck structure, including 6 males and 4 females, was dissected, and the position of mandible angle (MA) relative to the corresponding cervical spinal level was measured when the head was fixed in the flexion, anatomy position, and extension. The difference between the genders and the sides was analyzed. On the basis of the study of the corpse samples, the reference level of cervical spine was approximated to C2/3 intervertebral disc. The result has confirmed MA as a consistent and convenient landmark in the identification of cervical spinal level. Given some external landmarks do not consistently correspond to the exact level of the cervical spine, MA provides the relatively consistent reference point: C2/3 intervertebral disc. The authors hold that MA is a superior external landmark, which can help surgeons to localize the skin incision before anterior cervical spine surgery.

A Retrospective Study of 91 Patients Treated with Percutaneous Kyphoplasty for Mild Osteoporotic Vertebral Compression Fractures and a New Evaluation Scale of Shape and Filling Effect of Cement.

BACKGROUND: Percutaneous kyphoplasty (PKP) is commonly used to treat severe osteoporotic vertebral compression fractures (OVCFs) by restoring vertebral height. However, its application in mild cases is not frequently discussed. METHODS: The study retrospectively included 100 treated vertebral bodies of the 91 patients mentioned before, and efficacy was evaluated using visual analog scale (VAS) and Oswestry Disability Index (ODI) scores preoperatively, 2 days postoperatively, and at 1 and 6 months after treatment, as well as mean variation in vertebral body height. The study also examined complications such as pain recurrence, delayed vertebral fracture, and loss of vertebral height, and developed a scale to assess the shape and filling effect of cement (SFEC) and its impact on complications. RESULTS: The results showed significant reductions in mean VAS and ODI scores from pre-to post-surgery and an increase in vertebral body height. However, complications occurred in 10 patients who received treatment for 11 vertebral bodies, including pain recurrence, fractures, and loss of vertebral height. Among the 10 patients with complications, 7 (63.6%) vertebral bodies had dissatisfied SFEC scores, compared with 22 (24.7%) vertebral bodies with dissatisfied SFEC scores in 81 patients without complications (89 vertebral bodies). CONCLUSIONS: PKP is a safe and effective method for treating mild OVCFs, but attention should be paid to the shape and filling effects of cement during surgery to prevent later complications. The developed SFEC scale provides a specific and quantitative standards for evaluating the recovery status after PKP, which need further validations.

Exosome miR-4738-3p-mediated regulation of COL1A2 through the NF-κB and inflammation signaling pathway alleviates osteoarthritis low-grade inflammation symptoms.

This study aimed to elucidate the roles of microRNA (miR)-4738-3p and the collagen type I alpha 2 chain (COL1A2) gene in the pathogenesis of osteoarthritis (OA) through bioinformatics analysis and cellular assays. The GSE55235 dataset was analyzed using the weighted gene co-expression network analysis (WGCNA) method to identify gene modules associated with OA. Key overlapping genes were identified from these modules and the GSE55235-differential expressed genes (DEGs). The expression levels of selected genes were determined in C28/I2 cells using the quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between miR-4738-3p and COL1A2 was examined in the context of interleukin 1 beta (IL-1ß) induction. Exosome characterization was achieved through transmission electron microscopy (TEM), western blotting (WB), and other analyses. The study also investigated the functional relevance of miR-4738-3p in OA pathology through various molecular and cellular assays. Our findings revealed that the green module exhibited a strong correlation with the OA phenotype in the GSE55235 dataset, with COL1A2 emerging as a hub gene and miR-4738-3p as its key downstream target. IL-1ß induction suggested that COL1A2 is involved in inflammation and apoptosis, while miR-4738-3p appeared to play an antagonistic role. The analysis of exosomes underscored the significance of miR-4738-3p in cellular communication, with an enhanced level of exo-miR-4738-3p antagonizing IL-1ß-induced inflammation and promoting cell survival. Conversely, a reduction in exo-miR-4738-3p led to increased cell damage. This study established a clear regulatory relationship between miR-4738-3p and COL1A2, with the nuclear factor kappa B (NF-κB) signaling pathway playing a central role in this regulation. The miR-4738-3p significantly influences the OA-associated inflammation, primarily through modulation of COL1A2 and the NF-κB pathway. Therefore, targeting miR-4738-3p offers a potential therapeutic approach for OA, with exosome miR-4738-3p presenting a promising strategy.

Expression Profile Analysis of Long Non-coding RNA in OVX Models-Derived BMSCs for Postmenopausal Osteoporosis by RNA Sequencing and Bioinformatics.

Osteoporosis (OP) has the characteristics of a systematically impaired bone mass, strength, and microstructure. Long non-coding RNAs (lncRNAs) are longer than 200 nt, and their functions in osteoporosis is yet not completely understood. We first harvested the bone marrow mesenchymal stem cells (BMSCs) from ovariectomy (OVX) and sham mice. Then, we systematically analyzed the differential expressions of lncRNAs and messenger RNAs (mRNAs) and constructed lncRNA-mRNA coexpression network in order to identify the function of lncRNA in osteoporosis. Totally, we screened 743 lncRNAs (461 upregulated lncRNAs and 282 downregulated lncRNAs) and 240 mRNAs (128 upregulated and 112 downregulated) with significantly differential expressions in OP compared to normal. We conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional analyses to investigate the functions and pathways of the differential expression of messenger RNAs (mRNAs), a coexpressed network of lncRNA/mRNA. Quantitative PCR (qPCR) validated that the expressions of NONMMUT096150.1, NONMMUT083450.1, and NONMMUT029743.2 were all downregulated, whereas NONMMUT026970.2, NONMMUT051734.2, NONMMUT003617.2, and NONMMUT034049.2 were all upregulated in the OVX group. NONMMUT096150.1, as a key lncRNA in OP, was identified to modulate the adipogenesis of BMSCs. Further analysis suggested that NONMMUT096150.1 might modulate the adipogenesis of BMSCs via the peroxisome proliferator-activated receptor (PPAR) signaling pathway, AMPK signaling pathway, and the lipolysis regulation in adipocyte and adipocytokine signaling pathway. Our study expands the understanding of lncRNA in the pathogenesis of OP.

Circular RNA circFAT1(e2) Promotes Osteosarcoma Progression and Metastasis by Sponging miR-181b and Regulating HK2 Expression.

As a subclass of noncoding RNAs, circular RNAs (circRNAs) have been demonstrated to play a critical role in regulating gene expression in eukaryotes. Recent studies have revealed the pivotal functions of circRNAs in cancer progression. Nevertheless, how circRNAs participate in osteosarcoma (OS) development and progression are not well understood. In the present study, we identified a circRNA circFAT1(e2) with an upregulated expression level in OS tissues. By functional experiments, we found that circFAT1(e2) depletion significantly suppressed the proliferation and reduced migration in OS. In terms of mechanism, we found that circFAT1(e2) inhibited miR-181b, while miR-181b targeted HK2. By releasing the inhibition of miR-181b on HK2 expression, leading to attenuated OS progression. Mechanistic investigations suggested that circFAT1(e2) served as a competing endogenous RNA (ceRNA) of miR-181b to enhance HK2 expression. On the whole, our study indicated that circFAT1(e2) exerted oncogenic roles in OS and suggested the circFAT1(e2)/miR-181b/HK2 axis might be a potential therapeutic target.

Diagnostic accuracy of MR, CT, and ECT in the differentiation of neoplastic from nonneoplastic spine lesions.

AIM: To provide guidance for appropriate imaging examinations for diagnosing spinal tumors or tumor-like lesions. METHODS: A total of 121 patients with suspected spinal tumors were included this retrospective study. Each patient underwent ≥2 imaging examinations, including computerized tomography (CT), magnetic resonance (MR), and/or emission computed tomography (ECT). All patients were diagnosed by pathology after core needle or surgical biopsies. The results were compared with those of pathological examinations using paired chi-squared tests, and compared with each other. Statistical indicators that tested the consistency of the results included McNemar's and kappa coefficients, as well as receiver operating characteristic curves. RESULTS: The differences among MR, CT, ECT, and pathology were not significant. The kappa coefficient of MR, CT, and ECT was 46.1%, 36.0%, and 55.9%, respectively. The area under the curve of ECT, MR, and CT scans was 0.809, 0.705, and 0.704, respectively; and the differences among them were significant (P < .05). Post hoc multiple comparisons showed no significant differences among imaging examinations in terms of sensitivity, specificity, misdiagnosis rate, and coincidence rate (P > .05). However, significant differences were noted in the kappa coefficient and missed diagnosis rate (P < .05). CONCLUSIONS: Although ECT was the most accurate imaging method, its high cost and large radiation dosage limit its widespread application. Furthermore, MR verified spinal tumors more effectively; however, CT excluded them more efficiently. In summary, when all factors are considered, MR is still the optimal modality for the diagnosis of spinal tumors, especially during the initial screening.

Surgical Outcomes and Prognostic Factors for Metastatic Spine Hepatocellular Carcinoma.

BACKGROUND: We evaluated the surgical outcomes of metastatic spine hepatocellular carcinoma (HCC) and determined the factors that might influence the outcomes of metastatic HCC of the spine. METHODS: From 2010 to 2017, 72 patients with HCC-derived metastatic spine tumors were treated in our department. For each patient, we recorded the pre- and postoperative visual analog scale score, Frankel grade, perioperative complications, and mortality. Univariate and multivariate analyses were used to explore a range of factors that might influence postoperative survival. RESULTS: The mean postoperative survival was 10.8 ± 5.4 months. The concordance rate between a Tokuhashi score of 0-8 and a life expectancy of <6 months was only 19.2%. The mean postoperative survival for patients undergoing excisional surgery was 14.7 ± 6.5 months, and the mean survival of those receiving palliative surgery was 8.5 ± 2.6 months. Pain had significantly improved in both patient groups (P < 0.001). Paralysis did not change significantly in the excisional surgery group (P = 0.641) or palliative surgery group (P = 0.912). Univariate analysis showed that the preoperative Frankel score, Tomita score, Tokuhashi score, blood loss, multilevel metastases, and operative type were independent prognostic factors for postoperative survival time. Multivariate analysis showed that operation type was an independent factor for prognosis, just as were the Tomita score and Tokuhashi score. CONCLUSIONS: Our results have challenged previously reported estimates of the life expectancy correlating with the Tokuhashi score. Our results showed that excisional surgery resulted in better clinical outcomes compared with palliative surgery.

Gene expression profile analysis of the bone microenvironment in patients with spinal metastases.

The present study aimed to identify the underlying molecular mechanisms associated with spinal metastases. Gene expression profiles in cancellous bone samples from the spines of five patients with spinal metastases, with different primary cancers, and three normal control patients were measured using microarray analysis and subsequently compared. The differentially expressed genes (DEGs) identified were filtered using bioinformatics analyses followed by cluster analysis, gene ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. Finally, a protein-protein interaction network was constructed and analyzed. A total of 152 upregulated and 388 downregulated DEGs were identified. The cluster analysis demonstrated a marked difference between the gene expression profiles of samples from patients with spinal metastases and those from normal patients. The GO terms enriched in the upregulated DEGs were associated with cell death, and those enriched in the downregulated DEGs were associated with the cell cycle. The upregulated DEGs were enriched in signaling pathways associated with tight junctions, and the downregulated DEGs were enriched in signaling pathways associated with porphyrin metabolism. In the PPI network constructed, transcription factor AP-1 and proliferating cell nuclear antigen had the highest connectivity degrees with the upregulated and downregulated DEGs, respectively. The gene expression profile data from the present study provides new insights into the underlying molecular mechanisms of spinal metastases, and will aid in the development of novel anticancer treatments.

CX3CL1: a potential chemokine widely involved in the process spinal metastases.

OBJECTIVES: The aim of our study was to investigate the general mechanism of spinal metastases from five different primary cancers: lung cancer, breast cancer, liver cancer, prostate cancer, and kidney cancer. RESULTS: From microarray analysis and validation by real-time polymerase chain reaction, CX3C chemokine ligand 1 (CX3CL1) appeared to be a potential chemokine widely involved in the process of spinal metastases. Further studies revealed that, compared with normal controls, serum samples from patients with spinal metastases from the lung (P < 0.01), kidney (P < 0.05) and prostate (P < 0.05) contained significantly higher levels of CX3CL1, whereas those from patients with spinal metastases from the liver and breast had a tendency to contain higher levels of CX3CL1 but without significance. Immunohistochemical staining for the expression of CX3C chemokine receptor 1 (CX3CR1), the receptor for CX3CL1, in all spinal metastases samples showed negative staining. MATERIALS AND METHODS: Cancellous bone in the spine from patients with and without spinal metastases was collected for mRNA microarray study, and then differentially expressed mRNAs related to chemokines were further confirmed by real-time polymerase chain reaction. Enzyme linked immunosorbent assay was used to detect the serum level of the selected chemokines and immunohistochemical staining was used to detect the expression level of corresponding receptors in tumor. CONCLUSIONS: Our present study showed that CX3CL1 is associated with the process of spinal metastases from different primary cancers.

Bioabsorbable self-retaining PLA/nano-sized ß-TCP cervical spine interbody fusion cage in goat models: an in vivo study.

STUDY DESIGN: This is an experimental animal study. OBJECTIVE: The objective of this study was to compare an anterior cervical discectomy and interbody fusion of a novel polylactide/nano-sized ß-tricalcium phosphate (PLA/nß-TCP) bioabsorbable self-retaining cervical fusion cage (BCFC) with an autologous bone graft and polyetheretherketone (PEEK) cages. BACKGROUND: Although PLA cervical cages have potential advantages compared with traditional materials, they are not currently routinely used in spine surgery because of undesirable effects such as the lack of osteoconductivity and osteolysis around the implant. This study involved the manufacturing of a bioabsorbable cage from PLA/nß-TCP that was then used as a device for anterior cervical discectomy and fusion (ACDF) on a goat cervical spine fusion model. MATERIALS AND METHODS: Eighteen goats underwent C3/C4 discectomy and were randomly divided into three groups based on the following methods: Group A (n=6), an autologous bone graft; Group B (n=6), PEEK cage filled with an autologous graft; and Group C (n=6), BCFC filled with an autologous iliac bone. Radiography was performed preoperatively and postoperatively and at 1, 4, 8, and 12 weeks after the operation. Disc space height (DSH) was measured at the same time. After 12 weeks, the fused segments were harvested and evaluated with functional radiographic views, biomechanical testing, and histological analyses. RESULTS: Over a 12-week period, the BCFC and PEEK cage groups exhibited significantly higher DSH values than the bone graft group. Additionally, the BCFC group yielded a significantly lower range of motion in axial rotation than both the autologous bone graft and PEEK cage groups. A histologic evaluation revealed an increased intervertebral bone volume/total volume ratio and better interbody fusion in the BCFC group than in the other groups. CONCLUSION: The BCFC device exhibited better results than the autologous bone graft and PEEK cages in single-level ACDF models in vivo. This device may be a potential alternative to the current PEEK cages.

Degenerative Spondylolisthesis in the Fifth Lumbar Vertebra and Radiographic Parameters: A Correlation Analysis.

STUDY DESIGN: A retrospective study. OBJECTIVE: This study aimed to analyze the relationships between degenerative spondylolisthesis in the fifth lumbar vertebra (L5-DS) and radiographic parameters and to further determine the radiographic predictors of the development of L5-DS. SUMMARY OF BACKGROUND DATA: Degenerative lumbar spondylolisthesis (DLS) is a common degenerative disease of the spine; however, the correlations between L5-DS and radiographic parameters remain controversial. PATIENTS AND METHODS: This retrospective case-control study was conducted in our hospital. Between 2011 and 2014, a total of 84 subjects with L5-DS were enrolled in the DLS group, and 56 healthy volunteers were recruited to the control group. A series of radiographic parameters, including the bone mineral density, disk degenerative index, disk height, L5 vertebral size (L5-VS), lumbar lordosis angle (LL), sacral slope angle (SS), pelvic incidence (PI), facet joint angulations (FJA) of the cephalad and caudad portions, and asymmetry of the FJA, were measured in both groups by 3 examiners. RESULTS: The bone mineral density, disk degenerative index, disk height, L5-VS, LL, SS, PI, and FJA exhibited significant differences (P=0.014-0.045) between the DLS and control groups. Significant changes in the FJA of the cephalad and caudad portions in the L4-L5 and L5-S1 segments were observed between the 2 groups (P=0.00, 0.00), whereas no significant differences in the asymmetries of FJA were observed in the L4-L5 or L5-S1 segments (P=0.605-0.972). Among all of the parameters, the L5-VS (P=0.025), SS (P=0.020), LL (P=0.031), PI (P=0.014), and FJA (P=0.022) were identified as being associated with the DLS group by multiple logistic regression analysis. CONCLUSIONS: In this study, SS, LL, PI, and a more sagittal FJA were proven to be risk factors for L5-DS, whereas L5-VS was found to be a likely protective factor against L5-DS. These parameters should be considered predictors of L5-DS.

Role of CX3CL1 in Diseases.

Chemokines are a family of small 8-10 kDa inducible cytokines. Initially characterized as chemotactic factors, they are now considered to affect not just cellular recruitment. CX3CL1 is a unique chemokine that can exist in a soluble form, as a chemotactic cytokine, or in a membrane-attached form that acts as a binding molecule. Recently, the effects of CX3CL1 on diseases, such as inflammation and cancer, have been supported and confirmed by numerous publications. However, due to its dual effects, CX3CL1 exerts numerous effects on pathophysiological conditions that have both negative and positive consequences on pathogenesis and outcome. This review article summarizes the important scientific and clinical data that now point to a critical role for CX3CL1 in diseases.

Predictive value of pedicle involvement with MRI in spine metastases.

OBJECTIVES: The study aimed to retrospectively evaluate the accuracy and value of magnetic resonance imaging (MRI) in predicting pedicle involvement for patients with spine metastases. METHODS: Forty-five patients with a vertebral metastasis encroaching at least one pedicle were studied using MRI before surgery and regularly after surgery. Patients were categorized on the basis of their numbers of pedicle involvement (Group 1: one pedicle was involved, n = 23; Group 2: two pedicles were involved, n = 22). The diagnostic accuracy was calculated, and comparisons of intraoperative blood loss and recurrence rate between the two groups were performed. RESULTS: The overall performance of MRI in predicting the pedicle involvement was as follows: accuracy, 94.4%; sensitivity, 95.5%; and specificity, 91.3%. Less intraoperative blood loss was observed for Group 1 compared with Group 2 (1,661 ± 672 ml and 2,173 ± 790 ml, respectively, P = 0.024). Tumor relapse occurred in 8.7% (2/23) of Group 1 and in 22.7% (5/22) of Group 2 with median recurrence free survival time 14 and 9 months, respectively. CONCLUSIONS: MRI is a reliable approach to assess pedicle involvement. It has potential for use in the evaluation of the clinical characteristics of patients with spine metastases.

Surgery Combined with Radiotherapy to Treat Spinal Tumors: A Review of Published Reports.

Spinal tumors result in high morbidity and a high rate of lower limb paralysis. Both surgical therapy and radiation therapy (RT) are used to treat spinal tumors; however, how best to combine these two therapies to maximize the benefits and minimize the risks is still being debated. It is also difficult to decide the optimal timing, course and dose of RT, especially in pregnant women and children. The aim of this review is to assist surgeons who are dealing with spinal tumors by providing comprehensive information about advanced techniques for administering RT with greater precision and safety, and about the impact of various ways of combining surgery and RT on therapeutic outcomes. We here review published reports about treating spinal tumors with a combination of these two forms of therapy and attempt to draw appropriate conclusions concerning selection of optimal treatment protocols. Our conclusion is that postoperative radiotherapy, especially with high-precision, low-dose and multiple fractions, and brachytherapy are promising therapies to combined with surgery.