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Background Injection of cement during vertebroplasty and kyphoplasty can leak into surrounding structures and could be symptomatic. Purpose To identify the sites and incidence of cement extravasation after kyphoplasty and vertebroplasty, and to evaluate their impacts on clinical outcomes. Material and Methods A retrospective review of 316 patients treated with kyphoplasty and vertebroplasty; 411 cases were included (223 kyphoplasty and 188 vertebroplasty). Cement extravasation was evaluated postoperatively by computed tomography (CT) scan of the spine. Clinical outcomes were assessed by visual analog scale (VAS) and Oswestry Disability Index (ODI). Results There was a statistically significant difference in the incidence rate of cement extravasation between vertebroplasty and kyphoplasty groups ( P < 0.04). The most common site of cement extravasation was in paravertebral soft tissues for vertebroplasty (n = 33, 40.7%) and for kyphoplasty (n = 30, 30%). In the subgroup where cement leaked into the intradiscal space, adjacent vertebral body fractures occurred in 3/26 vertebrae (11.5%) in the vertebroplasty group and in 2/18 vertebrae (11.1%) in the kyphoplasty group. Both groups showed a statistically significant decrease in both VAS ( P < 0.001) and ODI scores ( P < 0.001). There was no significantly difference in patient satisfaction between those who had cement extravasation and those who did not, in both groups. Conclusion Kyphoplasty has an advantage in terms of less risk of cement extravasation. However, this factor did not reflect on subsequent sequelae or final clinical outcomes. This study did not find a distinct correlation between intradiscal cement extravasation and increased risk of adjacent vertebral fractures. [ABSTRACT FROM AUTHOR]

Myocardial ischemia/reperfusion (MI/R) injury is a major cause of cardiac dysfunction during cardiovascular surgery and heart transplantation and characterized by hyperactive oxidative stress and inflammatory response. Barbaloin (BAR) is the main medicinal composition of the Chinese traditional medicine aloe vera. BAR has strong anti-oxidant, anti-inflammatory and anti-tumor properties. However, the effect of BAR on MI/R-induced myocardial injury is not explored. This study aims to investigate whether BAR provides cardio-protection against MI/R injury and the underlying mechanisms. BAR (20 mg/kg/d) or vehicle was intragastrically administered to Sprague-Dawley rats for 5 days before MI/R operation. BAR pretreatment conferred cardio-protective effects against MI/R injury by improving hemodynamic function and limiting infarction size. Moreover, BAR pretreatment effectively inhibited I/R-induced myocardial oxidative stress and inflammatory response. Furthermore, BAR pretreatment activated adenosine monophosphate-activated protein kinase (AMPK) signaling in MI/R hearts. AMPK inhibitor compound C inhibited BAR-induced AMPK activation, and blunted BAR-mediated anti-oxidative, anti-inflammatory effects and cardio-protection. Taken together our study has identified a novel function of BAR and provided a molecular basis for BAR potential applications in the treatment of MI/R injury and other ischemic disorders. [ABSTRACT FROM AUTHOR]

Objective To report and evaluate the outcomes of patients undergoing definitive treatment for distal femur nonunion after initial treatment with a locking plate. Methods Fourteen patients who had undergone definitive treatment at an academic Level 1 trauma center from May 2007 to December 2013 for distal femur nonunion were identified from a fracture database. Thirteen of them were female; the average age was 65 years (range, 50-84 years). Ten patients had sustained their injuries in falls at ground level, and four in motor vehicle accidents. Twelve patients were obese (body mass index ≥30), 10 had diabetes, none were current smokers, and one had an open fracture classified as type IIIa according to the Gustilo-Anderson classification system for open fractures. The fractures were classified according to the AO classification system for distal femur fractures; there were three type 33-A1, six 33-A2, two 33-A3 and three 33-C3 fractures. Methods of definitive treatment involved open reduction and internal fixation ( ORIF) revision, medial plating, bone grafting and the use of other biologic materials. Results Eight of the 14 patients (57%) achieved union during follow-up. Definitive treatment for nonunion involved ORIF revision in 11 cases. Three patients who did not undergo ORIF revision were treated with iliac crest stem cell autografts, bone graft substitutes or recombinant human-bone morphogenetic protein-2 (rh- BMP-2). Other treatments included rh- BMP-2 (12 cases), iliac crest bone autograft (five), iliac crest stem cell autograft (two), crushed cancellous bone allograft (three), CaSO4 and tricalcium phosphate bone graft substitute (two) and demineralized bone matrix (one). The average time from definitive treatment to union was 19 weeks (range, 12-51 weeks). Two of the 11 cases who underwent ORIF revision had medial plates added to improve biomechanical stability and prevent varus collapse. This was also performed in one patient with a grade III open type 33-C3 fracture and one with a closed 33-A2 fracture. Five study patients had comminuted fractures. Two had type 33-A3 and three type 33-C3 fractures. Both patients with 33-A3 fractures and 2 two with 33-C3 fractures had persistent nonunion at the end of follow-up. Conclusions Definitive treatment of distal femur nonunion after initial treatment with a locking plate had a low rate of success in this study, suggesting that this procedure is ineffective as a definitive treatment for distal femur nonunion. [ABSTRACT FROM AUTHOR]

Background context Previous studies have demonstrated the use of bone marrow mesenchymal stem cells (BMSCs) in tissue-engineering treatments to slow or reverse diseased intervertebral discs. Several approaches have successfully used the coculturing of stem cells with disc-native nucleus pulposus cells (NPCs) with the evidence of transformed BMSCs into NP-like cells, increased activity and matrix production by NPCs, or elements of both. The influence of the cytokine transforming growth factor-beta (TGF-β) in the differentiation of BMSCs into NP-like cells and its upregulation in coculture to increase matrix production are well established. However, the role of the inflammatory signaling molecule nuclear factor kappa B (NF-κB) in intervertebral disc degeneration is far less clear, although there is some existing evidence suggesting its role in the pathogenesis and progression of disc disease. A limited number of studies in other pathologies have alluded to the antagonistic relationship between both proteins. To date, there is no such investigation of their dynamic role in coculture of BMSCs and NPCs. Purpose The purpose of this study was to investigate the relationship of the regenerative effects of BMSCs cocultured with NPCs. The authors hypothesized that as levels of TGF-β increase in the coculture, the levels of NF-κB will concomitantly decrease. This would in turn be reflected by an increase in the expression of messenger RNA markers of the nucleus pulposus matrix that includes aggrecan, Type II collagen (CII), and SOX-9 and an increase in the cellular proliferation. Study design/setting This study is based on a coculture with the contact of rabbit NPCs and BMSCs. Methods Bone marrow mesenchymal stem cells were cocultured with NPCs at a ratio of 1:1 and compared with BMSC and NPC controls cultured alone. Cell proliferation was evaluated by Cell Counting Kit-8 from 3 to 9 days. Gene expressions of aggrecan, CII, and SOX-9 was assayed by reverse transcription-polymerase chain reaction from 5 to 14 days. Detection of TGF-βl and NF-κB was determined by enzyme-linked immunosorbent assay, and immunohistochemical staining was carried out to evaluate CII synthesis. Results After 3 days, cellular proliferation of the cocultured group exceeded that of controls. After 11 days, the expression of SOX-9 in the cocultured group had also exceeded controls. Furthermore, after 14 days, expressions of aggrecan and CII significantly exceeded controls. Immunohistochemical stains of CII in the NPC control group were positive at each point in time and demonstrated strongest expression at 14 days. Coculturing BMSCs with NPCs, therefore, seems to have resulted in the promotion of aggrecan, CII, and SOX-9 gene expressions. Finally, after 11 days, TGF-βl content of the cocultured group significantly exceeded control levels, whereas NF-κB content had significantly lowered. Conclusions Coculture of BMSCs may be able to delay NPC matrix degeneration potentially through the concomitant upregulation of TGF-β and the downregulation of NF-κB pathway. [ABSTRACT FROM AUTHOR]

Abstract: Benzalkonium Chloride (BAC) is commonly used in eyedrops. Although the cytotoxicity of BAC has been reported, the mechanism underlying its toxic effect has not been elucidated. The present study investigated the role of the Wnt signaling pathway in the cytotoxicity of BAC in corneal epithelial cells and in the rat cornea. We demonstrated that phosphorylation of β-catenin, a downstream effector of the canonical Wnt pathway, was down-regulated by a short exposure to BAC in both cultured human corneal epithelial cells (HCE) and a cultured mouse corneal epithelial progenitor cell line (TKE2), suggesting an activation of the Wnt pathway. The activation of Wnt pathway is correlated with the decrease of cell viability induced by BAC. On the other hand, a specific Wnt pathway inhibitor, secreted frizzled-related protein-1 (sFRP1), reversed BAC-induced down-regulating effects on the level of phosphorylation of β-catenin and ameliorated cell viability in cells treated with BAC. In the rat cornea, the levels of total β-catenin were significantly up-regulated 8 h after the topical administration of BAC. Taken together, these results provided novel evidence suggesting that the cytotoxicity of BAC may be mediated through modulation of the Wnt pathway. [Copyright &y& Elsevier]

Abstract: Background: Many investigators have conducted studies to determine the biomechanics, causes, complications and treatment of unilateral facet joint dislocation in the cervical spine. However, there is no quantitative data available on morphological changes in the intervertebral foramen of the cervical spine following unilateral facet joint dislocation. These data are important to understand the cause of neurological compromise following unilateral facet joint dislocation. Methods: Eight embalmed human cadaver cervical spine specimens ranging from level C1-T1 were used. The nerve roots of these specimens at C5-C6 level were marked by wrapping a 0.12mm diameter wire around them. Unilateral facet dislocation at C5-C6 level was simulated by serially sectioning the corresponding ligamentous structures. A CT scan of the specimens was obtained before and after the dislocation was simulated. A sagittal plane through the centre of the pedicle and facet joint was constructed and used for measurement. The height and area of the intervertebral foramen, the facet joint space, nerve root diameter and area, and vertebral alignment both before and after dislocation were evaluated. Results: The intervertebral foramen area changed from 50.72±0.88mm2 to 67.82±4.77mm2 on the non-dislocated side and from 41.39±1.11mm2 to 113.77±5.65mm2 on the dislocated side. The foraminal heights changed from 9.02±0.30mm to 10.52±0.50mm on the non-dislocated side and 10.43±0.50mm to 17.04±0.96mm on the dislocated side. The facet space area in the sagittal plane changed from 6.80±0.80mm2 to 40.02±1.40mm2 on the non-dislocated side. The C-5 anterior displacement showed a great change from 0mm to 5.40±0.24mm on the non-dislocated side and from 0mm to 3.42±0.20mm on the dislocated side. Neither of the nerve roots on either side showed a significant change in size. Conclusions: The lack of change in nerve root area indicates that the associated nerve injury with unilateral facet joint dislocation is probably due to distraction rather than due to direct nerve root compression. [Copyright &y& Elsevier]