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Thiazolidinediones are traditional anti-diabetic therapeutic agents that have been associated with bone loss and increased fracture risk. However, the underlying mechanisms of this side effect require further elucidation. The present study aimed to investigate the effect of pioglitazone (PIO), a thiazolidinedione, on osteoblastogenesis, osteoclastogenesis and the osteoprotegerin (OPG) / receptor activator of nuclear factor-κB ligand (RANKL) / RANK system. The MC3T3-E1 murine pre-osteoblastic cell line was treated with PIO and processed for reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis of OPG, RANKL, peroxisome proliferator-activated receptor γ (PPARγ), Runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP) and osteocalcin (OCN), and western blotting analysis of OPG and RANKL. The culture medium was collected for ELISA analysis of OPG and RANKL. Murine bone marrow monocytes (BMMCs) were treated with PIO in the presence of RANKL and macrophage-colony stimulating factor and subjected to tartrate-resistant acid phosphatase (TRAP) staining and activity measurement, and RT-qPCR analysis of cathepsin K, TRAP and RANK. Co-culture of MC3T3-E1 and BMMCs was performed in the presence of PIO, and TRAP staining was also conducted. PIO inhibited the osteoblastic differentiation of MC3T3-E1 cells, and promoted the osteoclastic differentiation of BMMCs with or without co-culturing with MC3T3-E1 cells. ELISA analysis indicated increased RANKL and decreased OPG expression levels in the medium of MC3T3-E1 cells treated with PIO. PIO upregulated expression of RANKL and PPARγ and downregulated expression of OPG, RUNX2, ALP and OCN in MC3T3-E1 cells, while expression levels of RANK in BMMCs remained unchanged. These results suggest that PIO suppresses osteoblastogenesis and enhances osteoclastogenesis. In addition, PIO may also promote osteoclastogenesis by affecting the OPG-RANKL-RANK system. [ABSTRACT FROM AUTHOR]

We experimentally measure the angular distribution of plasma luminescence emission during the filamentation of linearly polarized femtosecond laser pulses. It is found that the luminescence from N2 shares the same intensity in all directions, while that from N+2 is more intense in the direction parallel to that of the laser polarization. The isotropic emission behavior of luminescence from N2 illustrates that the formation of excited N2(C3Πu+) does not result from the dissociative recombination; on the other hand, the linear increase of the strength of 337 nm signal with pressure indicates that the collision plays a negligible role, excluding the collision assisted intersystem crossing scheme. However, the intersystem crossing does not rely on the collision, making it a possible scheme. This study will be helpful to the understanding of mechanism of plasma luminescence emission during femtosecond filamentation. [ABSTRACT FROM AUTHOR]

Zoledronic acid (ZA), which is one of the most potent and efficacious bisphosphonates, has been commonly used in clinical practice for the treatment of various bone disorders. The extensive use of ZA has been associated with increasing occurrence of jaw complications, now known as bisphosphonate-associated osteonecrosis of the jaw (BRONJ). However, the mechanism underlying BRONJ remains to be fully elucidated. The aim of the present study was to investigate the effects of different concentrations of ZA on the MC3T3-E1 murine preosteoblast cell line cells and examine the possible pathogenesis of BRONJ. In the present study, the effect of ZA on the viability, apoptosis, differentiation and maturation of MC3T3-E1 cells, as well as its relevant molecular mechanism, were examined The results of a Cell Counting Kit 8 assay, a flow cytometric Annexin-V/propidium iodide assay and western blot analysis demonstrated that ZA exhibited a significant inhibition of cell viability and induction of apoptosis at concentrations >10 µM. Subsequently, the effect of ZA on cell differentiation at concentrations <1 µM were investigated. In this condition, ZA inhibited bone nodule formation and decreased the activity of alkaline phosphatase. The results of reverse transcription-quantitative polymerase chain reaction and western blot analyses indicated that ZA downregulated the expression levels of the marker genes and proteins associated with osteogenic differentiation. Further investigation revealed that the suppression of differentiation by ZA was associated with decreased expression of bone morphogenetic protein-2 (BMP-2) and downregulation of the phosphorylation levels in the downstream extracellular signal-regulated kinase 1/2 and p38 pathways. These adverse effects of ZA were observed to be concentration-dependent. The results from the present study suggested that ZA at higher concentrations induces cytotoxicity towards osteoblasts, and ZA at lower concentrations suppresses osteoblast differentiation by downregulation of BMP-2. These results assist in further understanding the mechanisms of BRONJ. [ABSTRACT FROM AUTHOR]

Objective Ameta-analysis comparing the efficacy and safety of minimally invasive and open transforaminal lumbar interbody fusion (TLIF) for degenerative lumbar diseases. Methods A literature search of PubMed, Embase, ScienceDirect, OVID, Google scholar, and Cochrane Library databases was conducted to identify relevant articles published before May 2013. Only studies that directly compared the efficacy and safety of minimally invasive and open TLIF in patients with degenerative lumbar diseases were selected. The main outcomes analyzed were the visual analog scale (VAS), Oswestry Disability Index (ODI), complications, and fusion rates. Also evaluated were intraoperative X-ray exposure, intra-postoperative blood loss, operating time, and hospitalization. Results The selected 14 studies included 494 patients who receivedminimally invasive TLIF and 500 patients given open TLIF. According to the Methodological Index for Non- Randomized Studies, the quality scores of the studies ranged from 11 to 19. No significant differences in preoperative VAS or ODI scores, operating time, complication rate, or fusion rate were observed between these two procedures. Compared with open TLIF, minimally invasive TLIF was associated with significantly less blood loss, shorter hospitalization, and lower VAS during follow-up assessment. However, minimally invasive TLIF involved significantly more intraoperative X-ray exposure. Conclusion Although the clinical efficacy, risk of complications and fusion rate were comparable between the two procedures, minimally invasive TLIF resulted in less blood loss, lower follow-up VAS score, and shorter perioperative hospitalization relative to open TLIF. [ABSTRACT FROM AUTHOR]

Amiloride is widely used in clinical practice as a diuretic and is known to interact with the epithelial sodium channel and acid-sensing ion channel proteins, as well as Na+/H+ antiporters and Na+/Ca2+ exchangers. The aim of the present study was to examine the effects of amiloride on receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis and to elucidate the underlying mechanisms in the RAW264.7 murine macrophage cell line. The number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells were counted and the bone resorption area was estimated. In addition the expression levels of nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) mRNA and osteoclast-specific genes, including TRAP, matrix metalloproteinase 9, cathepsin K and osteoclast-associated receptor, were examined using reverse transcription-quantitative polymerase chain reaction. The nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were also investigated using western blotting. The results showed that amiloride significantly reduced the number of TRAP-positive multinucleated cells as well as the bone resorption area. Amiloride also downregulated the expression of NFATc1 mRNA and inhibited the expression of osteoclast-specific genes. A possible underlying mechanism may be that amiloride suppresses the degradation of the inhibitor of NF-κB and blocks the activation of c-Jun N-terminal kinase, extracellular signal-regulated kinase and p38, thus implicating the NF-κB and MAPK pathway is this process. In conclusion, the current data suggest that amiloride is a strong inhibitor of osteoclast differentiation, indicating a novel indication for amiloride in the treatment of bone-loss-related diseases. [ABSTRACT FROM AUTHOR]

Ultrafast thermionic emission from gold film irradiated with a femtosecond laser pulse in the presence of an additional electric field is analyzed using a two-temperature equation combined with a modified Richardson equation. The calculated results show that the duration of the emission is below 1 ps. Supplying an additional electric field is found to change the emission from the metal surface. Given the same laser fluence, this additional field reduces the work function of the metal, and thus improves the efficiency of thermionic emission. These results help to understand the mechanism and suggest ways to improve emissions in the context of ultrafast thermalized electron systems. [ABSTRACT FROM AUTHOR]

Loss of E-cadherin and up-regulation of mesenchymal cadherins, a hallmark of the epithelial-mesenchymal transition, contributes to migration and dissemination of cancer cells. Expression of human cadherin-11 (Cad11), also known as osteoblast cadherin, in prostate cancer increases the migration of prostate cancer cells. How Cad11 mediates cell migration is unknown. Using the human Cad11 cytoplasmic domain in pulldown assays, we identified human angiomotin (Amot), known to be involved in cell polarity, migration, and Hippo pathway, as a component of the Cad11 protein complex. Deletion analysis showed that the last C-terminal 10 amino acids in Cad11 cytoplasmic domain are required for Amot binding. Further, Cad11 preferentially interacts with Amot-p80 than Amot-p130 isoform and binds directly to the middle domain of Amot-p80. Cad11-Amot interaction affects Cad11-mediated cell migration, but not homophilic adhesion, as deletion of Amot binding motif of Cad11 (Cad11-D Amot) did not abolish Cad11-mediated cell-cell adhesion of mouse L cells, but significantly reduced Cad11-mediated cell migration of human C4-2B4 and PC3-mm2 prostate cancer cells and human HEK293T cells. Together, our studies identified Amot-p80 as a novel component of the Cad11 complex and demonstrated that Amot-p80 is critical for Cad11-mediated cell migration. [ABSTRACT FROM AUTHOR]

The effect of type 2 diabetes mellitus (T2DM) on bone is controversial. Therefore, the present study investigated whether T2DM causes osteoporosis and explored the underlying mechanisms involved in this process. The effects of T2DM on bone physiology were analyzed in a mouse model of T2DM; KK/Upj-Ay/J (KK-Ay) mice develop diabetes after 8 weeks and exhibit stable diabetes symptoms and signs after 10 weeks when fed a KK-Ay mouse maintenance fodder. Diabetic mice exhibited hyperglycemia, hyperinsulinemia and increased body and fat pad weight in comparison with C57BL/6 non-diabetic mice. Furthermore, diabetic mice demonstrated low bone weight and bone mineral density in the femur, tibia and fifth lumbar vertebra. Using von Kossa and tartrate-resistant acid phosphatase (TRAP) staining, alkaline phosphatase and TRAP activity analyses and gene profiling it was demonstrated that osteoblastogenesis and osteoclastogenesis were impaired in diabetic mice. To evaluate the bone biomechanics, the ultimate load of the bone was analyzed. It was found that the ultimate load of the tibia in diabetic mice was lower than that in the controls. The results from the present study suggest that bone metabolism is impaired in T2DM, resulting in decreased osteoblastogenesis, osteoclastogenesis and bone mass. [ABSTRACT FROM AUTHOR]

A femtosecond double-pulse laser was used to induce the plasma of silicon in air. The laser wavelength was 800 nm. The interpulse delay of the femtosecond double-pulse was from -20 ps to 100 ps. During the experiment, the spectral line was fixed at the wavelength of 288.157 nm. The emission intensity was observed to lead to a significant increase by choosing the proper sample position. The range of the sample position is from 5.17 mm to 5.27 mm. And, the best sample position for the higher laser fluence was different from the position for the lower laser fluence. At the higher laser fluence, the optimized emission intensity can be obtained at either side of the best focal position for all interpulse delays of the double-pulse. The phenomena can be explained by the nonlinear propagation of the femtosecond laser pulse in air. At the lower laser fluence, the best sample position will change from one side to both sides with the increase of the interpulse delay of the double-pulse. The results showed that the effect of the sample position can be especially advantageous in the context of femtosecond double-pulse laser-induced breakdown spectroscopy. The study will lead a further improvement in the applications of the femtosecond double-pulse laser. [ABSTRACT FROM AUTHOR]

The article presents a study which differentiates the transplanted oligodendrocyte-like cells into rats with spinal cord injury (SCI). The study used insulin-like growth factor-1 (IGF-1) to induce the bone marrow differentiation into oligodendrocytes. Results show that the transplantation of oligodendrocytic-induced mesenchymal stem cells (MSC) promote functional recovery to SCI.

To study the effects of Icariin on expression of osteopontin (OPN) mRNA and type I collagen in rat osteoblasts in vitro and to explore its possible mechanisms in preventing osteoporosis. OB was isolated from calvaria of new-born new-born fetal Sprague-Dawley (SD) rats by means of modified sequential collagenase digestion and incubated in MEM medium and the cell morphology was observed under inverted phase contrast microscope, OB was identified by alkaline phosphatase (ALP) staining. Different concentration (0.1 μg/mL, 1.0 μg/mL, 10 μg/mL) of Icariin was added to the OB and incubated. The effect of Icariin on the proliferation and osteogenesis of OB was monitored by MTT analysis. The expression of type I collagen was estimated with immunohistochemistry techniques. The expression levels of mRNA of OPN in the cells in every group were examined by reverse-transcriptase polymerase chain reaction (RT-PCR). The expression of OPN mRNA and type I collagen was strengthened gradually with the increase of Icariin concentration and peaked with 10 μg/mL Icariin on the 5th day. Icariin could significantly promote the expression of OPN mRNA and type I collagen in rat osteoblasts in vitro. The levels of expression of OPN mRNA and type I collagen were changed with different concentration of Icariin. Icariin could effectively prevent and treat osteoporosis and promote the bone formation. [ABSTRACT FROM AUTHOR]