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ABSTRACT Ovarian cancer G protein-coupled receptor 1 (OGR1) has been shown to be a receptor for protons. We investigated the role of proton-sensing G protein-coupled receptors in the apoptosis of endplate chondrocytes induced by extracellular acid. The expression of proton-sensing G protein-coupled receptors was examined in rat lumbar endplate chondrocytes. Knockdown of OGR1 was achieved by transfecting chondrocytes with specific short hairpin RNA (shRNA) for OGR1. Apoptotic changes were evaluated by DNA fragmentation ELISA, electron microscopy, and flow cytometry. Intracellular calcium ([Ca2+]i) was analyzed with laser scanning confocal microscopy. The mechanism of OGR1 in acid-induced apoptosis of endplate chondrocytes was also investigated. We found that OGR1 was predominantly expressed in rat endplate chondrocytes, and its expression was highly upregulated in response to acidosis. Knocking down OGR1 with shRNAs effectively attenuated acid-induced apoptosis of endplate chondrocytes and increased [Ca2+]i. Blocking OGR1-mediated [Ca2+]i elevation inhibited acid-induced calcium-sensitive proteases such as calpain and calcineurin, and also inhibited the activation of Bid, Bad, and Caspase 3 and cleavage of poly (ADP-ribose) polymerase (PARP). OGR1-mediated [Ca2+]i elevation has a crucial role in apoptosis of endplate chondrocytes by regulating activation of calcium-sensitive proteases and their downstream signaling. © 2014 American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Sinibotia pulchra(Cypriniformes: Cobitidae) is a small cyprinid fish. In this study, the complete mitochondrial genome sequence ofS. pulchrais sequenced. TheS. pulchracomplete mitochondrial genome (GenBank accession no. KT362179) was a circular molecule of 16 568 bp in length, with 13 protein-coding genes (PCGs), 2 ribosome RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, an L-strand replication origin (OL) and a control region (D-loop). The nucleotide acid composition of the entire mitogenome was 31.69% for A, 25.63% for T, 26.94% for C and 15.74% for G, with an AT content of 57.32%. The AT content of 12S rRNA, 16S rRNA and D-loop was 50.21%, 56.86% and 66.74%, respectively. [ABSTRACT FROM AUTHOR]

Objective To study the gene expression of cardiac mesenchymal cells in patients with type 2 diabetes mellitus (T2DM)based on a whole-genome high-throughput sequencing dataset,screen differentially expressed genes,analyze the genetics signature of cardiac mesenchymal cells in T2DM patients by bioinformatics analysis,and explore the environmental chemicals related to the key differentially expressed genes. Methods The dataset GSE106177 was obtained from Gene Expression Omnibus (GEO) database.The dataset was pre-processed and analyzed by Network Analyst,Cytoscape 3.7.1,String11.0,CTD,and HMDD for screening for differentially expressed genes,enrichment analysis,establishment of protein-protein interaction (PPI) networks,and screening for relevant environmental chemicals. Results The gene expression pattern of cardiac mesenchymal cells in T2DM patients was significantly different from that in the control group.There were 135 differentially expressed genes,of which 58 (42.96%) were up-regulated and 77 (57.04%) were down-regulated.The differentially expressed genes mainly participated in biological processes such as multicellular organism development,anatomical structure development,and system development and were mainly involved in hepatocellular carcinoma,Cushing's syndrome,and cholesterol metabolism.PPI network showed that UBC was the core protein node.The microRNA-Gene interaction network showed that seven microRNAs,represented by hsa-mir-8485,interacted with the differentially expressed genes.Key T2DM related genes such as UBC,DNER,and CNTN1 interacted with bisphenol A. Conclusions The gene expression profile of cardiac mesenchymal cells markedly changes in T2DM patients,during which UBC may play an important biological role.Bisphenol A exposure may also affect the development and normal function of cardiac cells in T2DM patients.

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 β-tricalcium phosphate (PLA/nβ-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/nβ-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., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Zn(2+) is an essential component of metalloproteinases, and is required for their activity in cartilage; however, the effect of Zn(2+) on nucleus pulposus (NP) cells has not been widely investigated. The aim of this paper was to investigate the effect of intracellular Zn(2+) concentration ([Zn(2+)]i) in hypoxia-induced regulation of metalloproteinases (MMPs) and extracellular matrix (ECM) production in NP cells. NP cells from Sprague-Dawley (SD) rats were cultured as monolayers or in alginate beads. [Zn(2+)]i was assayed by FluoZin-3 AM staining. Alcian Blue staining, immunochemistry, 1,9-dimethylmethylene blue (DMMB) assay, and real-time PCR were used to assay collagen II, proteoglycan, and COL2A1, MMP-13, and ADAMTS-5 mRNA expression. ZIP8, a main Zn(2+) transporter in chondrocytes, was assayed by immunochemistry and in Western blotting. Interleukin (IL)-1β- and ZnCl2-induced increases of [Zn(2+)]i were significantly inhibited by hypoxia. Hypoxia did not reverse a decline of ECM expression caused by IL-1β and ZnCl2 in monolayer cultures, but did significantly attenuate the decreases of proteoglycan, glycosaminoglycan (GAG), and COL2A1 mRNA expression following IL-1β and ZnCl2 treatment in alginate bead cultures. However, ZnCl2 inhibited the protective effect of hypoxia. Both an intracellular Zn(2+) chelator and hypoxia prevented the increase in MMP-13 mRNA expression. IL-1β and ZnCl2 treatment increased ZIP8 expression in NP cells, and hypoxia inhibited ZIP8 expression. In conclusion, decrease of Zn(2+) influx mediates the protective role of hypoxia on ECM and MMP-13 expression. Consequently, changes in intracellular Zn(2+) concentration maybe involved in intervertebral disc degeneration.

Based on the cDNA sequence of GPX in Hyriopsis cumingii, the complete genomic DNA of GPX gene and it's 5'-flanking region were identified from H. cumingii using PCR and genome walking technique. The length of the complete genomic sequence was 6 708 bp including the 5'-flanking region, two exons, and one intron. Sequence analysis of the 992 bp 5'-flanking region revealed that it contained a core promoter element (TATA-box) and other transcription regulation elements such as AP1, C/EBP, and CdxA. The sequence lengths of the two exons were 273 bp and 991 bp, respectively, and the intron was 4 491 bp in length. Sixteen single nucleotide polymorphisms (SNPs) were detected in the GPX gene from resistant stock (RS) and susceptible stock (SS) of H. cumingii. These polymorphisms were analyzed with regard to resistance to Aeromonas hydrophila. Among them, three SNPs including A-99G, A-86C, and A-49C in GPX promoter and five SNPs including A2841T, C2847T, G3146C, A3150G, and G4645T in GPX introns were associated with resistance/susceptibility of H. cumingii to A. hydrophila, both in genotype and allele frequency. Linkage disequilibrium analysis revealed that A-86C, A-49C, C2847T, A3150G, G4645T, A2841T, and G3146C were in high linkage disequilibrium, and haplotype analysis revealed that the frequency of two major predominant haplotypes (ACTGT and TG) in the resistant group was significantly higher than that in the susceptible group. The results suggest that the polymorphic loci in the GPX gene could be potential genetic markers for future molecular selection of strains resistant to diseases.

Objective: To compare the safety and efficacies of traditional open versus percutaneous monosegmental pedicle screw fixation in the treatment of incomplete thoracolumbar spinal fracture., Methods: A retrospective analysis was conducted for 44 inpatients with a diagnosis of incomplete thoracolumbar spinal fracture (AO classification: A3.1 and A3.2) undergoing monosegmental pedicle instrumentation (MSPI) from September 2008 to January 2011. There were 24 cases in percutaneous group and 20 cases in traditional open group. The mean operative duration, blood loss, blood drainage, visual analogue scale/score (VAS) and vertebral kyphotic angle at pre- and post-operation were evaluated., Results: No significant differences existed in operative durations between two groups (P > 0.05). Significant differences between two groups were observed in terms of intra-operative blood loss and VAS scores at Week 1 postoperation (P < 0.05). There were no significant differences in VAS score preoperation, 1 year postoperation or pre-and post-operative vertebral kyphotic angle (P > 0.05). No complications of iatrogenic neurological injury or hardware failure occurred., Conclusion: The application of percutaneous monosegment pedicle instrumentation in the treatment of thoracolumbar fractures in type of A 3.1 and A 3.2 is both feasible and safe. Its postoperative therapeutic effect is comparable to that of traditional open monosegmental fixation.

Purpose: The aim of this study was to investigate the biomechanical stability provided by a novel, polylactic acid/nano-sized, β-tricalcium phosphate, bioabsorbable, self-retaining cervical fusion cage (BCFC)., Methods: Quasistatic nonconstraining torques (maximum 1.5 NM) induced flexion, extension, lateral bending (±1.5 NM), and axial rotation (±1.5 NM) on 32 sheep cervical spines (C2-C5). The motion segment C3-C4 was first tested intact; the following groups were tested after complete discectomy: autologous tricortical iliac crest bone graft, Medtronic-Wego polyetheretherketone (PEEK) cage, Solis PEEK cage, and BCFC. The autologous bone graft group was tested with an anterior plate. The mean range of motion (ROM) was calculated from the load-displacement curves., Results: BCFC significantly decreased ROM in lateral bending and axial rotation compared to other implants, and no significant difference in ROM between two types of PEEK cages and BCFC could be observed in flexion and extension. Anterior cervical plate (ACP) significantly decreased ROM in flexion and extension, but no significant difference in ROM between BCFC and bone graft plus ACP could be determined in lateral bending and axial rotation., Conclusion: The BCFC device showed better stability to autologous tricortical iliac crest bone graft and PEEK cages in single-level anterior cervical discectomy and fusion models and thus may be a potential alternative to the current PEEK cages.

The purpose of this study was to investigate the influence of nano-sized β-tricalcium phosphate (β-TCP) on the biological performance of poly (lactic acid) (PLA) composite scaffolds by using in vitro degradation and an in vivo model of heterotopic bone formation. Nano-sized β-TCP (nβ-TCP) was prepared with a wet grinding method from micro-sized β-TCP (mβ-TCP), and composite scaffolds containing 0, 10, 30, or 50 wt% nβ-TCP or 30 wt% mβ-TCP were generated using a freeze-drying method. Degradation was assessed by monitoring changes in microstructure, pH, weight, and compressive strength over a 26-week period of hydrolysis. Composite scaffolds were processed into blocks, and implanted into muscular pockets of rabbits after loading with recombinant human bone morphogenetic protein-2 (rhBMP-2). New bone formation was evaluated based on histological and immunohistochemical analysis 2, 4, and 8 weeks after implantation. The in vitro results indicated that the buffering effect of nβ-TCP was stronger than mβ-TCP, which was positively correlated with the content of nβ-TCP. The in vivo findings demonstrated that nβ-TCP enhanced the osteoconductivity of the scaffolds. Although composite scaffolds containing 30% nβ-TCP exhibited similar osteoconductivity to 50% nβ-TCP, they had better mechanical properties than the 50% nβ-TCP scaffolds. This study supports the potential application of a composite scaffold containing 30% nβ-TCP as a promising scaffold for bone regeneration.

Objective: To investigate the safety and therapeutic effects of monosegment pedicle instrumentation in treating incomplete thoracolumbar burst fracture., Methods: A retrospective analysis was conducted on 56 inpatients with incomplete thoracolumbar burst fracture (AO classification: A3.1 and A3.2) from April 2005 to January 2010. There were 28 cases were fixed with monosegment pedicle instrumentation (MSPI), 28 cases were fixed with short segment pedicle instrumentation (SSPI). The operative time, blood loss, visual analogue scale (VAS) and vertebral kyphotic angle (VK) before and after surgery were evaluated., Results: In the group of MSPI, the mean operative time was (93 ± 20) min; the intraoperative blood loss was (184 ± 64) ml; the VK angle was 17° ± 10° before operation, 7° ± 7° at one week after operation, and 10° ± 7° at latest follow-up; VAS score was 7.6 ± 1.5 before operation, 2.4 ± 0.8 at one week after operation, and 1.5 ± 0.9 at latest follow-up; no adjacent segment degeneration was found. In the group of SSPI, the operative time was (102 ± 30) min; the intraoperative blood loss was (203 ± 88) ml; the VK angle was 17° ± 9° before operation, 7° ± 7° at one week after operation, and 8° ± 5° at latest follow-up; VAS score was 6.8 ± 1.3 before operation, 3.1 ± 0.5 at one week after operation, and 1.2 ± 0.7 at latest follow-up. One case of adjacent segment degeneration was found in 36 months after operation. There were no significantly statistical differences between two groups in operative time, blood loss, VAS score and VK angle before and after surgery (P > 0.05). The VAS score and VK angle at one week after surgery and latest follow-up all decreased obviously than preoperative ones in both groups (P < 0.05)., Conclusions: MSPI for incomplete thoracolumbar burst fracture is effective and safe. The operative blood loss, the mean operative time, the improvement of VAS score and the VK angle in group MSPI are equal to those in group SSPI.

Based on the EST sequence of mantle cDNA library of Hyriopsis cumingii, the complete cDNA of Hyriopsis cumingii GPX gene was cloned by rapid amplification of cDNA ends (RACE) in this paper. The GPX full-length cDNA sequence was 1286 bp including a 39 bp 5'-untranslated region, a 659 bp 3'-untranslated region and an open reading frame (ORF) 588 bp in length, which encodes for 195 amino acids with the predicted molecular weight of 22.2 kDa and the isoelectric point of 8.44. Molecular structure analysis revealed that GPX was Se-GPX. The amino acid sequences have three highly conserved loop structures that have a stabilizing effect on the tertiary structure of the enzyme. The amino acid sequence did not contain obvious hydrophobic domain and signal peptide. Homologous analysis of amino acid sequences indicated that the GPX of H. cumingii shared a high similarity with GPX-2 and GPX-1 of vertebrates (73.1%-80.8%), and low similarity with other types (lt; 60%). Phylogenetic trees showed that GPX of Hyriopsis cumingii was clustered together with GPX of some fishes and far away from GPX of several other published Molluscas. These results indicated GPX gene of H. cumingii cloned in this study was different from the GPX genes from other Molluscas.