CircATRNL1 protects against osteoarthritis by targeting miR-153-3p and KLF5.

BACKGROUND: Osteoarthritis (OA) is characterized by chondrocyte injury. Circular RNAs (circRNAs) are involved in the pathogenesis of various diseases, including OA. The purpose of this study was to determine the potential role of circATRNL1 in OA pathology in vitro. METHODS: Human chondrocytes were isolated and treated with interleukin-1 beta (IL-1ß) to mimic OA in vitro. High-throughput RNA sequencing was performed to identify differentially expressed circRNAs, miRNAs and mRNAs between IL and 1ß-treated chondrocytes and normal chondrocytes. The expression of circATRNL1, miR-153-3p and KLF5 was measured using quantitative real-time polymerase chain reaction (qRT-PCR). For functional analyses, cell apoptosis was assessed using a flow cytometry assay. Extracellular matrix (ECM) degradation was monitored by measuring the levels of ECM-associated proteins by Western blot. The potential target miRNAs of circATRNL1 were screened by bioinformatics analysis and verified by dual-luciferase reporter assay. RESULTS: The expression of circATRNL1 was decreased in IL-1ß-treated chondrocytes. CircATRNL1 overexpression ameliorated cell apoptosis and ECM degradation, which were promoted by IL-1ß treatment. Mechanistic analysis revealed that circATRNL1 directly targeted miR-153-3p and that miR-153-3p could reverse the inhibitory effects of circATRNL1 overexpression on inflammatory responses, cell apoptosis and ECM degradation. KLF5 is a target of miR-153-3p. CONCLUSION: Taken together, the results in this study suggested that circATRNL1 might ameliorate the development and progression of OA through regulating miR-153-3p/KLF5 axis. Our study increased the understanding of circRNAs as therapeutic targets in the treatment of OA.

Comprehensive Effects of Suppression of MicroRNA-383 in Human Bone-Marrow-Derived Mesenchymal Stem Cells on Treating Spinal Cord Injury.

BACKGROUND/AIMS: Transplantation of bone-marrow-derived mesenchymal stem cells (MSCs) promotes neural cell regeneration after spinal cord injury (SCI). Recently, we showed that suppression of microRNA-383 (miR-383) in MSCs increased the protein levels of glial cell line derived neurotrophic factor (GDNF), resulting in improved therapeutic effects on SCI. However, the overall effects of miR-383 suppression in MSCs on SCI therapy were not determined yet. Here, we addressed this question. METHODS: We used bioinformatics tools to predict all miR-383-targeting genes, confirmed the functional bindings in a dual luciferase reporter assay. The effects of alteration of candidate genes in MSCs on cell proliferation were analyzed by MTT assay and by Western blotting for PCNA. The effects on angiogenesis were assessed by HUVEC assay. The effects on SCI in vivo were analyzed by transplantation of the modified MSCs into nude rats that underwent SCI. RESULTS: Suppression of miR-383 in MSCs not only upregulated GDNF protein, but also increased vascular endothelial growth factor A (VEGF-A) and cyclin-dependent kinase 19 (CDK19), two other miR-383 targets. MiR-383-suppression-induced increases in CDK19 resulted in a slight but significant increase in MSC proliferation, while miR-383-suppression-induced increases in VEGF-A resulted in a slight but significant increase in MSC-mediated angiogenesis. CONCLUSIONS: Upregulation of CDK19 and VEGF-A by miR-383 suppression in MSCs further improve the therapeutic potential of MSCs in treating SCI in rats.

Suppression of MicroRNA-383 Enhances Therapeutic Potential of Human Bone-Marrow-Derived Mesenchymal Stem Cells in Treating Spinal Cord Injury via GDNF.

BACKGROUND/AIMS: Transplantation of bone-marrow-derived mesenchymal stem cells (MSCs) has been used to treat spinal cord injury (SCI) to enhance tissue repair and neural cell regeneration. Glial cell line derived neurotrophic factor (GDNF) is an identified neural growth and survival factor. Here, we examined whether modification of GDNF levels in MSCs may further increase the potential of MSCs in promoting neural cell regeneration and subsequently the therapeutic outcome. METHODS: We examined the mRNA and protein levels of GDNF in human MSCs by RT-qPCR and Western blot, respectively. Bioinformatics analyses were done to predict microRNAs (miRNAs) that target GDNF in MSCs. The functional binding of miRNAs to GDNF mRNA was examined by a dual luciferase reporter assay. MSCs were transduced with adeno-associated virus (AAV) carrying null or antisense for miR-383 (as-miR-383), which were transplanted into nude rats that underwent SCI. The intact tissue, cavity volume, and recovery of locomotor activity were assessed. RESULTS: MSCs expressed very low GDNF protein, but surprisingly high levels of GDNF mRNA. Bioinformatics analyses showed that miR-383 inhibited protein translation of GDNF, through binding to the 3'-UTR of the GDNF mRNA. MSCs transduced with AAV-as-miR-383 further increased the intact tissue percentage, decreased cavity volume, and enhanced the recovery of locomotor activity in nude rats that underwent SCI, compared to MSCs. CONCLUSIONS: Suppression of miR-383 may increase the therapeutic potential of human bone-marrow-derived MSCs in treating SCI via augmentation of GDNF protein levels.

[Research on Grape Deterioration Process via Volatiles -Using Long Optical-Path Infrared Spectroscopy and Simplified E-Nose].

Grapes vaporize volatiles in specific compositions and concentrations during deterioration processes. Our previous study demonstrated that it is possible to analyze grapes spoilage stages by using the infrared spectra of their volatiles. However, only the spectral characteristics of alcohol, ethyl acetate and carbon dioxide were observed in the experiment because of the low concentration of the volatiles. In this paper, the sensitivity of the spectrometry system was enhanced by increasing the optical-path with multi-reflecting mirrors. We used the new spectrometry system to study the details of the infrared spectra of the volatiles from grapes during spoilage, and observed the spectral characteristics of several kinds of ethanol, esters, aldehyde and ethylene. The concentrations of some components in the volatiles changes with storage time, which can be a biomarker to represent the spoilage stages of grapes. Chemometrics were used to analyze the spectral bands of ethanol and esters, demonstrating there are obvious differences between fresh and decayed grapes. Furthermore, we developed a simplified E-nose system comprised by sensor array, based on the results of spectral analysis. The classification and discrimination of grape spoilage were tested with E-nose. This was a further study of the previous publication and had given a more precise observation of the infrared spectral characteristics of the volatiles from decayed grapes. This study provided a basis for developing real-time monitoring techniques of fruits deterioration.

[Monitoring of Winter Wheat Aboveground Fresh Biomass Based on Multi-Information Fusion Technology].

The aim was to find a nondestructive way to improve the accuracy of detecting the winter wheat aboveground fresh biomass(AGFB). In this study, data fusion technology of the spectroscopy technology and the machine vision technology were used to analyze the AGFB and solve the problem that the accuracy of the prediction model of a single technology is not high. In this experiment, canopy spectra and canopy pictures of 93 samples at seeding stage were collected. Canopy spectra and side images of 200 samples at medium and later growth stage were collected. Spectral reflectance as the spectral absorption parameter was used to construct the AGFB prediction models based on the spectra technology at different stages; The wheat coverage were extracted from canopy pictures and side images by using image processing technology to build the AGFB prediction models. Multivariate regression analysis (MRA) and Partial least-squares regression analysis(PLS) were implemented on the feature variables from the spectral information and image information. The results showed that, compared with the individual image model and spectral model, the AGFB prediction models of PLS based on multi-information at different stages shows better performance. At the seeding stage, the determination coefficient (R2) of PLS models based on multi-information was 0.881，and the RMSE was 0.015 kg. The R2 of PLS models based on multi-information was 0.791, the RMSE was 0.059 kg at middle and final stages. It demonstrated that the precision of model based on multi-information fusion technology, which increased utilization of image and spectral information, was improved for AGFB detecting, which is than the individual image model and spectral model.

Actinomycin D inhibits cell proliferations and promotes apoptosis in osteosarcoma cells.

Actinomycin D (ActD), a well known transcription inhibitors, has been widely reported to induce cell apoptosis in several types of tumor cells by inhibiting the anti-apoptotic gene transcriptions. However, how ActD affects osteosarcoma cells survival and its molecular mechanism is currently unclear. In the present study, results of proliferation assays and Hoechst stainings suggested that MG63 human osteosarcoma cells showed impaired cell proliferations and significant apoptosis after ActD treatment. Moreover, biochemical results showed that cleaved caspase-3 is gradually increased with the increasing ActD concentrations and treated times. Importantly, results of western blots indicated that protein levels of cyclin factors, such as cyclin A, D1 and E, were all reduced after ActD treatment. And ActD treatments may inhibit mRNA transcription levels of these cyclin factors, which may finally lead to cell cycle arrest and consequently apoptosis. The present study have revealed a novel mechanism by which ActD inhibits osteosarcoma cell proliferations and induces apoptosis, and will provide an useful clue to chemotherapy in future treatment of osteosarcoma.

[A Study of FTIR Spectrometry Based on a Long Optical Path on the Emission Rules of Nitrous Oxide from Soil].

The excessive emission of N2O (Nitrous oxide) will destroy the ozone layer, reasonable fertilization and adopting measures of emission reduction of N2O are of great significance to slowing down the greenhouse effect. The article studied the impact of fertilization and water on the emission of N2 0 from the cabbage farmland using FTIR spectrometry. To enhance the sensitivity of the measuring system, we used multi-reflecting mirrors to increase the optical pathlength. By comparing the infrared spectra between the before and after fertilizer application and the NIST spectral library, finally, the band at 2160-2225 cm⁻¹ was chosen as the spectral characteristics band of quantitative calculation of N2O through analyzing. The research found that fertilization and water could promote the emission of N2 0 from the cabbage farmland soil, which could supply theory bases for emission reduction of N2O and slowing down the greenhouse effect. Finally, we also studied the diurnal emission rules of N2O from the fertilized soil; the results showed that the emission of N2O was lower at night and the results were compared with that of previous' studies, which verifies the feasibility of this method. The results proved that FTIR with long optical path was a rapid and effective method to measure the emission rules of N2O from the cabbage farmland soil, which can measure the gas emissions of N2O from the fertilized cabbage farmland soil and compared with other traditional measuring methods, it had the advantages such as rapidness and convenience.

[Application of Fourier transform infrared spectroscopy in identification of wine spoilage].

In the present work, fresh and spoiled wine samples from three wines produced by different companies were studied u- sing Fourier transform infrared (FTIR) spectroscopy. We analyzed the physicochemical property change in the process of spoil- age, and then, gave out the attribution of some main FTIR absorption peaks. A novel determination method was explored based on the comparisons of some absorbance ratios at different wavebands although the absorbance ratios in this method were relative. Through the compare of the wine spectra before and after spoiled, the authors found that they were informative at the bands of 3,020~2,790, 1,760~1,620 and 1,550~800 cm(-1). In order to find the relation between these informative spectral bands and the wine deterioration and achieve the discriminant analysis, chemometrics methods were introduced. Principal compounds analysis (PCA) and soft independent modeling of class analogy (SIMCA) were used for classifying different-quality wines. And partial least squares discriminant analysis (PLS-DA) was applied to identify spoiled wines and good wines. Results showed that FTIR technique combined with chemometrics methods could effectively distinguish spoiled wines from fresh samples. The effect of classification at the wave band of 1 550-800 cm(-1) was the best. The recognition rate of SIMCA and PLSDA were respectively 94% and 100%. This study demonstrates that Fourier transform infrared spectroscopy is an effective tool for monitoring red wine's spoilage and provides theoretical support for developing early-warning equipments.

[Research on error reduction of path change of liquid samples based on near infrared trans-reflective spectra measurement].

Based on sucrose solution as the research object, this paper measured the trans-reflective spectrum of sucrose solution of different concentration by the technique of near infrared spectrum in three optical path (4, 5, 6 mm). Five kinds of pretreatment method (vector normalization, baseline offset correction, multiplicative scatter correction, standard normal variate transformation, a derivative) were used to eliminate the influence of the optical path difference, and to establish model of the calibration set in combination with the PLS (Partial Least Squares)method. Five kinds of pretreatment method could restrain the inter ference of light path in varying degrees. Compared with the PLS model of original spectra, the model of multiple scattering correction combined with PLS method is the optimal model. The results of quantitative analysis of original spectra: the number of principal component PC= 6, the determination coefficient R2 = 0.891 278, the determination coefficient of cross validation R2CV = 0.888 374, root mean square error of calibration RMSEC = 1.704%, root mean square error of cross validation RMSECV = 1.827%; The results of quantitative analysis of spectra after MSC pretreatment: the number of principal component PC = 3, the determination coefficient R2 = 0.987 535, the determination coefficient of cross validation R2CV = 0.983 343, root mean square er- ror of calibration RMSEC = 0.89%, root mean square error of cross validation RMSECV = 1.05%. The correlation coefficient of the prediction set is as much as 0.976 22. root mean square error of prediction is 0.01, lesser than 0.014 36. The results show that the MSC can eliminate the influence of optical path difference, improve the prediction precision and improve the stability.

Promotion of peripheral nerve regeneration of a peptide compound hydrogel scaffold.

BACKGROUND: Peripheral nerve injury is a common trauma, but presents a significant challenge to the clinic. Silk-based materials have recently become an important biomaterial for tissue engineering applications due to silk's biocompatibility and impressive mechanical and degradative properties. In the present study, a silk fibroin peptide (SF16) was designed and used as a component of the hydrogel scaffold for the repair of peripheral nerve injury. METHODS: The SF16 peptide's structure was characterized using spectrophotometry and atomic force microscopy, and the SF16 hydrogel was analyzed using scanning electron microscopy. The effects of the SF16 hydrogel on the viability and growth of live cells was first assessed in vitro, on PC12 cells. The in vivo test model involved the repair of a nerve gap with tubular nerve guides, through which it was possible to identify if the SF16 hydrogel would have the potential to enhance nerve regeneration. In this model physiological saline was set as the negative control, and collagen as the positive control. Walking track analysis and electrophysiological methods were used to evaluate the functional recovery of the nerve at 4 and 8 weeks after surgery. RESULTS: Analysis of the SF16 peptide's characteristics indicated that it consisted of a well-defined secondary structure and exhibited self-assembly. Results of scanning electron microscopy showed that the peptide based hydrogel may represent a porous scaffold that is viable for repair of peripheral nerve injury. Analysis of cell culture also supported that the hydrogel was an effective matrix to maintain the viability, morphology and proliferation of PC12 cells. Electrophysiology demonstrated that the use of the hydrogel scaffold (SF16 or collagen) resulted in a significant improvement in amplitude recovery in the in vivo model compared to physiological saline. Moreover, nerve cells in the SF16 hydrogel group displayed greater axon density, larger average axon diameter and thicker myelin compared to those of the group that received physiological saline. CONCLUSION: The SF16 hydrogel scaffold may promote excellent axonal regeneration and functional recovery after peripheral nerve injury, and the SF16 peptide may be a candidate for nerve tissue engineering applications.

[Pretreatment method of near-infrared diffuse reflection spectra used for sugar content prediction of pears].

The content of sugar is an important quality index for pears. However, the traditional sugar measurement methods are time-consuming and destructive. In the present study, the authors measured the sugar content of pears using visible and near infrared diffuse reflection spectroscopy. The pretreatment methods of multiplicative scatter correction (MSC), baseline correction, standard normal variate (SNV) transformation, and moving average algorithms were used on the original absorbance spectrum. Results indicate that the absorbance spectra after pretreatment are better than the original absorbance spectra for prediction. Partial least squares (PLS) regression was also used on the original absorbance spectrum and the absorbance spectrum after moving average and baseline correction. It follows that the forecast accuracy of the absorbance spectra after moving average is higher than that of the original absorbance spectra. The models gave good predictions of the sugar content of pears, with corresponding r values of 0.990 8, and standard errors of predictions of 0.019 0.

[Determination of potassium in farmland soil using laser-induced breakdown spectroscopy].

The real-time measurement of potassium in farmland soil has great importance. A method to determine the potassium content in farmland soil based on laser-induced breakdown spectroscopy (LIBS) was studied using a LIBS equipment consisting of a 1,064 nm laser generator and a high resolution spectrometer. The farmland soil samples with potassium content in the range of 8.74-34.56 g.kg-1 were analyzed. The 766.49 nm was chosen as the analysis line, by comparing the potassium atom characteristic lines of 404.40, 404.72, 766.49 and 769.90 nm. The errors of characteristic line strength caused by the laser stability and random noise was analyzed. The silicon, which is nearly constant in farmland soil, was chosen as the standard element, and a calibration model between the ratio of potassium to silicon (K/Si) and the potassium content was established. The linear fitting degree of the calibration curve was 0.935, and the relative standard deviation of the calibration model for prediction set samples was 9.26%.

[Laser-induced fluorescence spectroscopy characterization of farmland soil moisture content].

Online measurement of soil moisture is significant for agricultural production. The abundance and deficiency of leaf water shortage has been able to effect measured by fluorescence, but the research of correlation between soil moisture and laser-induced fluorescence spectroscopy has not been carried out yet. In this paper, the relationship between laser-induced plant chlorophyll fluorescence and soil moisture was studied. In the experiment with rice as the research object, the chlorophyll fluorescence induced by a 450 nm LED light source was measured by a Y-shaped fiber probe, and the soil moisture was obtained by TDR sensors. The changes in the peak intensity near 743 nm of chlorophyll fluorescence under continuous water stress and intermittent water stress were studied. The result showed that the intensity decreased with the soil moisture content. Finally, the model between the soil water content and the intensity of chlorophyll fluorescence under continuous water stress was created by using Lorentzian equation, and the coefficient of determination (R2) of the model was high. The result indicated that the method mentioned in paper can be applied to measure soil moisture in agricultural production.

[Optimizing algorithm design of piecewise linear classifier for spectra].

Being able to identify pollutant gases quickly and accurately is a basic request of spectroscopic technique for envirment monitoring for spectral classifier. Piecewise linear classifier is simple needs less computational time and approachs nonlinear boundary beautifully. Combining piecewise linear classifier and linear support vector machine which is based on the principle of maximizing margin, an optimizing algorithm for single side piecewise linear classifier was devised. Experimental results indicate that the piecewise linear classifier trained by the optimizing algorithm proposed in this paper can approach nonolinear boundary with fewer super_planes and has higher veracity for classification and recognition.

[Gene expression profile in acute spinal cord injury screened by cDNA microarray: experiment with rats].

OBJECTIVE: To investigate the characteristic changes of expression of the genes with specific functions in acute spinal cord injury (SCI). METHODS: Nine SD rats were randomly divided into 3 equal groups: SCI 8-hour group in which modified Allen's falling strike method was used to establish spinal cord contusion model, the spinal cords were taken out 8 hours later to undergo examination of the gene expression profile by using cDNA microarray including 13 200 gene, 12 genes were selected to undergo semi-quantitative RT-PCR, and the up-regulation of the candidate gene C/EBPdelta was verified by in situ hybridization and immunohistochemistry.; SCI 72-hour group undergoing the same treatment, however, with the spinal cord taken out 72 hours later; and control group undergoing only sham operation with the spinal cord taken out immediately. RESULTS: In the SCI 8 hour group the expression of 52 genes differed in comparison with the control group, 30 genes, including those related to transcription factors, oxidative stress, complement, pro-inflammatory reaction, and anti-inflammatory reaction, were up-regulated and 22 genes related to ion channel, synaptic proteins, and cytoskeletal proteins, were down-regulated. In the SCI 72-hour group the expression of 44 genes with known functions related to growth/differentiation/survival, axonal guidance, neuron regeneration, signal transduction, ubiquitin-proteasome system, and tumor suppressor differed, 26 genes were up-regulated and 18 down-regulated, in comparison with the control group. Semi-quantitative RT-PCR results of the 12 genes were consistent with those by the microarray examination. CONCLUSION: Significant changes occur in the early stage of SCI. Expressed at a high level in SCI, C/EBPdelta may be a therapeutic target of SCI.