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This study analyzed the action of Bone marrow mesenchymal stem cells (BMSCs) transplantation on arthritis rat model. Arthritis rat model was established using bovine type II collagen and CFA. BMSCs phenotype was assessed by flow cytometry and pathological changes was analyzed by H&E staining along with analysis of joint severity by AI score, inflammation by ELISA as well as level of NPY, MMP-2, and MMP-9. The form of passaged BMSCs was spindle shaped with positive expression of CD29 and CD44. The structure of articular cavity in arthritis rats was disordered with infiltration of inflammatory cells which were ameliorated by BMSCs transplantation. In addition, BMSCs treatment also significantly reduced AI value, the level of VEGF, IL-17 and TNF-α as well as decreased RANK/RANKL expression and increased OPG level. In conclusion, BMSCs transplantation ameliorates inflammation and severity in arthritis rats possibly through regulation of RANK/OPG, indicating that it might be used for the treatment of arthritis patients.

This study analyze the effect of exosome secreted from MSCs on osteogenic differentiation in OP rats. The exosome was obtained from cultivated MSCs isolated from OP rats with ultracentrifugation. OP rats were treated with exosome secreted from MSCs of normal rats, exosome secreted from MSCs of OP rats and exosome secreted from MSCs of OP rats with overexpression of ALP followed by analysis of the osteogenic differentiation, the expression of ALP, Bglap and Runx2 and the targeted correlation between miR-351 and ALP. The MSCs in normal rats and OP rats were able to adhere to wall. There was elongated. The level of miR-351 in OP rats was significantly higher than normal rats. The Runx2 expression and ALP activity in rats treated with exosome secreted from MSCs of OP rats was declined significantly compared to that from MSCs of normal rats. ALP was a target gene of miR-351. In conclusion, the exosome secreted from MSCs of OP rats inhibits the osteogenic differentiation possibly through restraining miR-351-ALP.

We aimed to explore the mechanism underlying microRNA-23-5p from exosomes (exo-miR-23-5p) of BMSCs in rheumatoid arthritis (RA). The candidate related genes of miR-23-5p were screened in RA by bioinformatics analysis through gain- and loss-function method along with analysis of histopathological changes in mice and RAC2 expression as well as the level of pro-inflammatory factors. In vivo RA model was established to detect miR-23-5p’s effect on RA. miR-23-5p level was significantly reduced in RA cells and RAC2 was highly expressed. Expression of RAC2 was inhibited and targeted by miR-23-5p in RA. Exo-miR-23-5p treatment effectively alleviated joint destruction, reduced inflammatory factor secretion in tissues and serum, as well as decreased RAC2 expression in RA model. In conclusion, the miR-23-5p in the BMSC-exo delays the inflammatory response in RA, indicating that it might be a new target for treating RA.

Dioscorea opposita Thunb has the effect of anti-osteoporosis, but whether its active ingredient diosgenin (DIO) has an anti-osteoporosis effect is unknown. The purpose of this study is to investigate the effect of DIO on the proliferation and differentiation of MG-63 cells. MG-63 cells were treated with different concentrations of DIO (0.001, 0.01, 0.1 and 1 μM) or 20 mM Wnt/β-catenin signaling agonist-LiCl, and then their cell cycle and viability were analyzed by flow cytometry and 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), respectively. To investigate osteoblast differentiation, alizarin red staining and ultraviolet spectrophotometer were used to determine the number of calcified nodules and the activity of alkaline phosphatase (ALP), respectively. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting were used to detect the expressions of proliferation-related, osteogenic-related and Wnt/β-catenin signal pathway-related factors. After the cells were treated with low-concentration (0.001 or 0.01 μM) DIO, cell viability was significantly increased and the proportion of cells in S phase was increased. In addition, low-concentration DIO could significantly increase the expression of Ki67, proliferating cell nuclear antigen (PCNA), osteopontin (OPN), and osteocalcin (BGP), promote osteoblast differentiation, and suppress the expression of β-catenin, Runx2 and cyclinD1. However, high concentrations of DIO showed the opposite effect. Low-concentration DIO obviously reversed the effect of LiCl on decreasing the number of calcified nodules and inhibiting the expression of OPN and BGP in cells. Low-concentration DIO might promote the proliferation and differentiation of MG-63 cell by inhibiting the Wnt/β-catenin signal pathway.

As a compact light source with high output power, quantum cascade laser has excellent performance in the range of 1-5THz. By using THz QCL optical comb spectrum in this frequency range, drugs and industrial waste gas can be quickly and effectively detected and identified. In this paper, we report a semi-insulating surface-plasmon waveguide THz QCL emitting at 5 THz operating in continuous-wave mode at 4K. For the device with 3-mm-long cavity and 150-µm-wide ridge, the continuous peak power is up to 13mW and the total spectral range is about 5cm-1. Furthermore, the stable optical comb is achieved in the range of 0.93-1.11A.

We demonstrate InP-based buried grating coupled surface-emitting distributed feedback (DFB) lasers designed to operate at a wavelength of 2004 nm. The laser structure consists of three InGaAsSb/InGaAs QWs, with a 5 $\mu \text{m}$ wide double-channel ridge waveguide. A second-order semiconductor/semiconductor grating is used for in-plane feedback and vertical out-coupling. The single longitudinal mode emission wavelength of the fabricated laser can be adjusted from 2002.7 to 2006 nm without any mode hopping. High side-mode suppression ratio (SMSR) of at least 35 dB is achieved under all injection currents and temperature conditions. The edge output power reaches 19 mW, measured in continuous-wave (CW) mode at 10 °C. Simultaneously, the output power of surface emission reaches 8 mW.

High-power, low-threshold stable single-mode operation buried distributed feedback quantum cascade laser by incorporating sampled grating emitting at λ ~ 4.87 μm is demonstrated. The high continuous wave (CW) output power of 948 mW and 649 mW for a 6-mm and 4-mm cavity length is obtained at 20 °C, respectively, which benefits from the optimized optical field distribution of sampled grating. The single-mode yields of the devices are obviously enhanced by controlling cleaved positions of the two end facets precisely. As a result, stable single-mode emission and mode tuning linearly without any mode hopping of devices are obtained under the different heat sink temperatures or high injection currents.

In this paper, we report a spectral beam combining technique based on discrete quantum cascade lasers at l~ 4.8 mm. Good beam qualities of M 2 < 1.3 for both fast and slow axes are obtained. The entire spectrum span is approximately 29.1 cm -1 , which is consistent with the theoretical results of grating equation. Maximum beam combining efficiency of 58.9% with output power exceeding 1 W is demonstrated under continuous wave operation at room temperature. The limit of beam combining efficiency is theoretically investigated. The independent temperature control for the discrete lasers circumvented the issue of thermal crosstalk between the lasers on an array and pave the way to high power and high efficiency laser spectral beam combining.

Background Osteosarcoma is the most common primary malignant tumor of skeleton in adolescence. Histone deacetylase 2 (HDAC2), a member of class I histone deacetylase, is putatively involved in tumorigenesis of human malignancies. This study aimed to evaluate the expression pattern and prognostic value of HDAC2 in osteosarcoma.Methods Four datasets were obtained from the gene expression omnibus (GEO) database to explore the expression and prognostic value of HDAC2. Level 3 mRNA expression profiles and clinical data were obtained in The Cancer Genome Atlas (TCGA) for validation. Expression pattern of HDAC2 were illustrated in GSE16088, GSE36001 and GSE42352. The prognostic value of HDAC2 was evaluated and validated by Kaplan-Meier analyses, receiver operating characteristic (ROC), concordance index (C-index) and calibration curve in GSE21257 and TCGA. Multivariate Cox regression analysis, nomogram, and decision curve analysis (DCA) were performed to assess the prognosis predictive capability. Protein-protein interaction (PPI) and gene set enrichment analysis (GSEA) were applied to further understand the molecular network and regulatory mechanisms.Results HDAC2 expression was significantly increased in osteosarcoma tissues. High HDAC2 expression was associated with tumor metastasis and chemotherapy efficacy. Kaplan-Meier analysis demonstrated that high HDAC2 predicted worse overall survival. The ROC curve showed good performance in survival prediction. Cox regression demonstrated that HDAC2 could be an independent prognostic indicator. GSEA revealed patients with high HDAC2 expression were enriched with multiple ontological signatures.Conclusions Elevated expression of HDAC2 may identify an aggressive subgroup in osteosarcoma and serve as an independent prognostic indicator in these patients.

Long noncoding RNAs (lncRNAs) have been identified to modulate the tumorigenesis of human cancers. The in-depth of lncRNAs on human osteosarcoma oncogenesis is still ambiguous. In present study, functional and mechanism experiments were conducted to investigate the role of long intergenic non-protein coding RNA 00858 (LINC00858) on human osteosarcoma tumorigenesis. Results demonstrated that LINC00858 expression was significantly upregulated in both osteosarcoma tissues and cell lines. Mechanism assays presented that LINC00858 silencing significantly repressed osteosarcoma cells' proliferation and invasion in vitro, and inhibited the tumor growth in vivo. In further experiments, LINC00858 was identified to sponge miR-139 to form RNA-induced silencing complex (RISC) using luciferase reporter assay and RNA immunoprecipitation (RIP). Besides, CDK14 was validated to be the target protein the miR-139. Rescue experiments confirmed the role of LINC00858/miR-139/CDK14 pathway on osteosarcoma cells' phenotype. In summary, these data prove that LINC00858/miR-139/CDK14 axis promotes the tumorigenesis of osteosarcoma, providing a new mechanism or target for osteosarcoma.

We demonstrate a broad gain, continuous-wave (CW) operation InP-based quantum cascade laser (QCL) emitting at 11.8 μm with a modified dual-upper-state (DAU) and diagonal transition active region design. A 3 mm cavity length, 16.5 μm average ridge wide QCL with high-reflection (HR) coatings demonstrates a maximum peak power of 1.07 W at 283 K and CW output power of 60 mW at 293 K. The device also shows a broad and dual-frequency lasing spectrum in pulsed mode and a maximum average power of 258.6 mW at 283 K. Moreover, the full width at half maximum (FWHM) of the electroluminescent spectrum measured at subthreshold current is 2.37 μm, which indicates a broad gain spectrum of the materials. The tuning range of 1.38 μm is obtained by a grating-coupled external cavity (EC) Littrow configuration, which is beneficial for gas detection.

In this paper, we designed a multimode interference (MMI) structure to simplify the fabrication of quantum cascade laser (QCL) phase-locked arrays. The MMI geometry is optimized with a sufficient output channel distance to accommodate conventional photolithography and wet etching processes by which power amplifier array is fabricated without using the complicated two-step etching-regrowth or dry etching technique. The far-field pattern with periodically modulated peaks reveals that the beams from the arrays are phased locked. Furthermore, the frequency tuning performance of the MMI-based phase-locked arrays is studied using the Littrow-configuration external cavity structure. A wavelength tuning range of more than 60 cm-1 is demonstrated, which would eventually lead to the realization of high power, frequency tunable, large-scale phase-locked arrays and their application in spectroscopy.

In this work, we demonstrated high-power quantum cascade laser (QCL) arrays lasing at λ ~ 5 µm by employing an optimized coupled-ridge waveguide (CRW) structure. Five-element QCL arrays were simulated and fabricated through a two-step etching method to extend the CRW structure to a mid-wave infrared regime. A lateral far-field with the main peak near a diffraction-limited intensity curve of about 10° was observed by properly designing a geometric shape of the ridges and interspaces. By introducing a buried 2nd-order distributed feedback (DFB) grating, substrate emission with a radiation power above 1 W at 25 °C is achieved. Single longitudinal mode operation is obtained by changing the temperature of the heatsink with a good linear wavelength tuning coefficient of –0.2 cm–1/K.

In this paper, an anomalous spectral data of distributed Bragg reflector (DBR) quantum cascade lasers (QCLs) emitting around 7.6 μm is presented. The two-section DBR lasers, consisting of a gain section and an unpumped Bragg reflector, display an output power above 0.6 W in continuous wave (CW) mode at room temperature. The anomalous spectral data is defined as a longitudinal mode which moves toward shorter wavelengths with increasing temperature or injection current, which is unexpected. Although the longer wavelength modes are expected to start lasing when raising device temperature or injection current, occasional mode hops to a shorter wavelength are seen. These anomalous mode transitions are explained by means of modal analysis. The thermal-induced change of the refractive index implied by an increase in the temperature or injection current yields nearly periodic transitions between cavity modes.

Osteosarcoma is a prevalent primary malignant tumor and long non-coding RNAs (lncRNAs) have been validated to modulate the osteosarcoma tumorigenesis. In present study, our research team investigates the role of a novel identified lncRNA DICER1-AS1 on the tumor progression and autophagy. Results showed that lncRNA DICER1-AS1 was up-regulated in osteosarcoma cells using microarray analysis and RT-PCR. Cellular functional experiments revealed that DICER1-AS1 knockdown suppressed the proliferation, migration, invasion and autophagy of osteosarcoma cells in vitro. Besides, DICER1-AS1 knockdown inhibited the protein expression levels of ATG5, LC3-II and Beclin 1, suggesting the inhibition on the autophagy of osteosarcoma cells. Moreover, miR-30b was verified to target 3'-UTR of DICER1-AS1 and ATG5 using bioinformatics tools and luciferase reporter assay or RNA-immunoprecipitation (RIP). Western blot showed that ATG5 protein expression was decreased in DICER1-AS1 knockdown and miR-30b mimics transfected cells, while increased in miR-30b inhibitor transfected cells, presenting a negative correlation with miR-30b and a positive correlation with DICER1-AS1. Finally, xenograft assay in vivo indicated that DICER1-AS1 knockdown inhibited the osteosarcoma tumor growth and protein expression level of ATG5. In summary, all the results conclude that DICER1-AS1 regulates the proliferation, invasion and autophagy of osteosarcoma via miR-30b/ATG5 axis, providing a novel insight for osteosarcoma tumorigenesis.

High power and high brightness InP based lasers around 2 µm are attractive for many applications due to their intrinsic compatibility with photonic integrated circuits. However, high output power and low lateral divergence are difficult to be realized simultaneously with the traditional ridge waveguide structure. In this paper, we demonstrate significantly enhanced performance of 1.96 µm InP based InGaAs quantum well lasers by tapered waveguide structures. The double-channel waveguide laser with a straight waveguide section and a small-angle tapered optical amplifier section showed fundamental transverse mode lasing with an excellent beam quality. In agreement with our designed waveguide structures, the devices’ lateral divergence is remarkably reduced. For the device with a 3° tapered angle, the narrowest full width at half maximum (FWHM) of 8.2° of the far-field distribution is realized and the continuous-wave output power, measured at 25 °C, is increased up to 40 mW, which is much higher than the 12 mW of the laser with only a straight ridge waveguide.

Single-stack InAsSb self-assembled quantum dashes (QDashes) laser grown by metalorganic vapor phase epitaxy based on InP (001) substrate is reported. High-quality InAsSb quantum dashes have been acquired under the optimized growth conditions, such as substrate temperature, growth rate, deposition thickness and V/III ratio. Surface QDashes morphologies have been characterized by atomic force microscopy whereas the ones buried in active region have been investigated by transmission electron microscope with high resolution X-ray Energy Dispersive Spectroscopy to confirm the antimony composition. Double channel waveguide laser with 40 μm width ridge has been fabricated by standard optical lithography and wet etching. Pulsed room temperature operation demonstrates the wavelength from 1.72 to 1.79 μm for different injection currents. In addition, the laser peak output power can exceed 600 mW with 12.8% of differential quantum efficiency and even under continuous wave operation, the maximum optical power still remains 26 mW.

We numerically simulate Kerr comb generation in an anomalous dispersion microcavity by modal expansion method and demonstrate that the initiation of comb generation is affected by the change of local dispersion possibly caused by avoided mode crossings. We also quantitatively analyze the instantaneous phase matching of different modes and reveal the characteristics of energy distribution in different modes in the dynamics of comb generation. We demonstrate that the local dispersion change can control the Kerr comb to transform between Type I and Type II combs. We also find that local dispersion is closely related to the stability of the power of Kerr comb lines, something that can change the dynamical state of the system near the Hamiltonian-Hopf bifurcation under an anomalous dispersion regime from a quasi-periodic oscillation state to a periodic state (Turing patterns).

Background To compare reactions to warning labels presented on cigarette packages with a specific focus on whether the new Chinese warning labels are better than the old labels and international labels. Methods Participants aged 18 and over were recruited in two cities of Jiangsu Province in 2008, and 876 face-to-face interviews were completed. Participants were shown six types of warning labels found on cigarette packages. They comprised one old Chinese label, one new label used within the Chinese market, and one Chinese overseas label and three foreign brand labels. Participants were asked about the impact of the warning labels on: their knowledge of harm from smoking, giving cigarettes as a gift, and quitting smoking. Results Compared with the old Chinese label, a higher proportion of participants said the new label provided clear information on harm caused by smoking (31.2% vs 18.3%). Participants were less likely to give cigarettes with the new label on the package compared with the old label (25.2% vs 20.8%). These proportions were higher when compared to the international labels. Overall, 26.8% of participants would quit smoking based on information from the old label and 31.5% from the new label. When comparing the Chinese overseas label and other foreign labels to the new Chinese label with regard to providing knowledge of harm warning, impact of quitting smoking and giving cigarettes as a gift, the overseas labels were more effective. Conclusion Both the old and the new Chinese warning label are not effective in this target population.