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Background: Most patients with breast cancer in advanced stages of the disease suffer from bone metastases which lead to fractures and nerve compression syndromes. microRNA dysregulation is an important event in the metastases of breast cancer to bone. microRNA-124 (miR-124) has been proved to inhibit cancer progression, whereas its effect on bone metastases of breast cancer has not been reported. Therefore, this study aimed to investigate the role and underlying mechanism of miR-124 in bone metastases of breast cancer. Methods: In situ hybridization (ISH) was used to detect the expression of miR-124 in breast cancer tissues and bone metastatic tissues. Ventricle injection model was constructed to explore the effect of miR-124 on bone metastasis in vivo. The function of cancer cell derived miR-124 in the differentiation of osteoclast progenitor cells was verified in vitro. Dual-luciferase reporter assay was conducted to confirm Interleukin-11 (IL-11) as a miR-124 target. The involvement of miR-124/IL-11 in the prognosis of breast cancer patients with bone metastasis was determined by Kaplan-Meier analysis. Results: Herein, we found that miR-124 was significantly reduced in metastatic bone tissues from breast cancers. Down-regulation of miR-124 was associated with aggressive clinical characteristics and shorter bone metastasis-free survival and overall survival. Restoration of miR-124 suppressed, while inhibition of miR-124 promoted the bone metastasis of breast cancer cells in vivo. At the cellular level, gain of function and loss-of function assays indicated that cancer cell-derived miR-124 inhibited the survival and differentiation of osteoclast progenitor cells. At the molecular level, we demonstrated that IL-11 partially mediated osteoclastogenesis suppression by miR-124 using in vitro and in vivo assays. Furthermore, IL-11 levels were inversely correlated with miR-124, and up-regulation IL-11 in bone metastases was associated with a poor prognosis. Conclusions: Thus, the identification of a dysregulated miR-124/IL-11 axis helps elucidate mechanisms of breast cancer metastases to bone, uncovers new prognostic markers, and facilitates the development of novel therapeutic targets to treat and even prevent bone metastases of breast cancer. [ABSTRACT FROM AUTHOR]

Objective To investigate the feasibility and safety of en bloc resection of cervical primary malignant bone tumors by a combined anterior and posterior approach based on a three-dimensional (3- D) printing model. Methods Five patients with primary malignant bone tumors of the cervical spine underwent en bloc resection via a one-stage combined anteroposterior approach in our hospital from March 2013 to June 2014. They comprised three men and two women of mean age 47.2 years (range, 26-67 years). Three of the tumors were chondrosarcomas and two chordomas. Preoperative 3- D printing models were created by 3- D printing technology. Sagittal en bloc resections were planned based on these models and successfully performed. A 360° reconstruction was performed by spinal instrumentation in all cases. Surgical margins, perioperative complications, local control rate and survival rate were assessed. Results All patients underwent en bloc excision via a combined posterior and anterior approach in one stage. Mean operative time and estimated blood loss were 465 minutes and 1290 mL, respectively. Mean follow-up was 21 months. Wide surgical margins were achieved in two patients and marginal resection in three; these three patients underwent postoperative adjuvant radiation therapy. One vertebral artery was ligated and sacrificed in each of three patients. Nerve root involved by tumor was sacrificed in three patients with preoperative upper extremity weakness. One patient (Case 3) had significant transient radiculopathy with paresis postoperatively. Another (Case 4) with C4 and C5 chordoma had respiratory difficulties and pneumonia after surgery postoperatively. He recovered completely after 2 weeks' management with a tracheotomy tube and antibiotics in the intensive care unit. No cerebrovascular complications and wound infection were observed. No local recurrence or instrumentation failure were detected during follow-up. Conclusion Though technically challenging, it is feasible and safe to perform en bloc resection of cervical primary bone tumors. This is the most effective means of managing cervical spine tumors. Preoperative 3- D printing modelling enables better anatomical understanding of the relationship between the tumor and cervical spine and can assist in planning the surgical procedure. [ABSTRACT FROM AUTHOR]

Abstract: We have developed a novel flexible pH sensor based on a polymeric substrate by low-cost sol–gel fabrication process of iridium oxide (IrO x ) sensing film. A pair of miniature IrO x /AgCl electrodes on a flexible substrate generated electrical potentials in solutions by electrochemical mechanisms responding to their pH levels. Our flexible IrO x pH sensors exhibited promising sensing performance with a near-Nernstian response in sensitivity repeatedly and reversibly between −51.1mV/pH and −51.7mV/pH in the pH range between 1.5 and 12 at 25°C. The fabrication processes including sol–gel deposition, thermal oxidation, and AgCl electro-plating on polymeric substrates were reported. The performance and characterization of the flexible pH sensors in sensitivity, response time, stability, reversibility, repeatability and selectivity were also discussed. Our IrO x pH electrodes on a deformable substrate demonstrated their sensing capability while they were conformed to a curved surface inside a limited space with distinct responding potentials at various pH levels similar to the traditional glass-rod pH electrodes. [Copyright &y& Elsevier]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

Abstract: Distributed MEMS phase shifters using CMOS-grade low-resistivity silicon have been successfully developed. Kapton films were utilized as dielectric layers to reduce RF signal attenuation in the lossy silicon substrate. The scattering parameters were evaluated from DC to 26GHz. The phase shifting reaches 43° and insertion losses are less than 1.4dB. The manufacturing process is simple and compatible with CMOS and post CMOS processes. [Copyright &y& Elsevier]