Topographical cues provided by micropatterns on material surfaces have been demonstrated to control multiple cell functions. However, the majority of currently studied micropatterns fail to ...recapitulate the key characteristics of an osteon, which is the structural unit of natural cortical bone. Thus, in the present study, a micropatterned polycaprolactone (PCL) surface comprising a series of concentric circular microgrooves was fabricated by combining photolithography with the melt-casting method to mimic the concentric structure of an osteon in a two-dimensional setting. By culturing mouse mesenchymal stem cells (mMSCs) and osteoclast progenitor cells (RAW264.7 cells) on the osteon-like concentric microgrooved surface, the effects of this micropatterned surface on the osteogenesis of mMSCs and the osteoclastogenesis of RAW264.7 cells were systematically investigated. Osteoclastogenic differentiation was significantly inhibited in RAW264.7 cells on the fabricated osteon-like concentric microgrooved surface compared to that on the parallel linear microgrooved and flat surfaces, as indicated by the downregulated expression of key osteoclast-specific function genes (TRAP, CATK and MMP9), the lower activity of TRAP and less formation of TRAP-positive multinucleated giant osteoclasts. Further investigation indicated that RANK-NFκB signaling may have been involved in mediating the inhibited osteoclastogenesis of RAW264.7 cells by the osteon-like concentric microgrooved surface. In addition, the osteon-like concentric microgrooved surface greatly modulated the osteoclastogenic-related paracrine secretion of mMSCs (RANKL, M-CSF and OPG), despite its small effect on the osteogenesis of mMSCs. This secretory profile was found to be able to effectively inhibit osteoclastogenesis in RAW264.7 cells, confirming the enhanced osteoclastogenesis inhibitory functions of mMSCs on the osteon-like concentric microgrooved surface. Our findings demonstrate the importance of the microgroove orientation and arrangement in affecting cellular behaviors and highlight the potential benefits of incorporating osteon-like concentric microgrooved patterns on the surface of scaffolds for bone repair.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Sensitive and rapid analysis of zearalenone (ZEN) in grains and feed is essential to guarantee the food security for human health. Herein a chemiluminescence method was demonstrated to measure the ...content of zearalenone in food samples. An immunomagnetic beads-anti-ZEN monoclonal antibody complex was prepared. Besides, the immunomagnetic beads were utilized as the solid support for rendering the immunoassay through the rapid formation of immune complexes in the solution, rapid separation and efficient heterogeneous detection. Under the optimal experimental parameters, the standard curve of ZEN detection is
y
= − 0.3839x + 0.1565 (
R
2
= 0.9978), the signal ratio has a well linear relationship with the logarithm of ZEN concentration in the range of 0.03–2.43 ng/mL. The limit detection of zearalenone in the developed assay was 0.01 ng/mL. The applicability of the reported approach for zearalenone detection in grains was demonstrated. In addition, the good recoveries of zearalenone were obtained, ranging from 85.15 to 102.60% at 5, 50, 150 ng/g spiked ZEN concentrations. The relative standard deviation was < 10%. The proposed chemiluminescence immunoassay is sensitive, simple, rapid and reliable for monitoring of zearalenone contamination, which provides a powerful avenue for further application of other mycotoxin in food analysis.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Resveratrol, extracted from Chinese herbal medicine Polygonum cuspidatum, is known to inhibit invasion and metastasis of human colorectal cancer (CRC), in which long non-coding Metastasis Associated ...Lung Adenocarcinoma Transcript 1 (RNA-MALAT1) also plays an important role. Using MALAT1 lentiviral shRNA and over-expression constructs in CRC derived cell lines, LoVo and HCT116, we demonstrated that the anti-tumor effects of resveratrol on CRC are through inhibiting Wnt/β-catenin signaling, thus the expression of its target genes such as c-Myc, MMP-7, as well as the expression of MALAT1. In detail, resveratrol down-regulates MALAT1, resulting in decreased nuclear localization of β-catenin thus attenuated Wnt/β-catenin signaling, which leads to the inhibition of CRC invasion and metastasis. This finding of ours surely provides important pre-clinical evidence supporting future use of resveratrol in prevention and treatment of CRC.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this study, a sensitive high-performance liquid chromatography method for zearalenone determination in feeds and grains was established based on the automatic immunomagnetic bead purifier analyzer ...(KY-AMI-I) for the one-step sample pre-treatment. Various parameters that may affect the analytical performance were investigated. Immunomagnetic bead separation system based on a monoclonal antibody (anti-ZEN antibody-immunomagnetic beads conjugation) was individually prepared for the ZEN purification. Besides, the average recoveries in spiked samples ranged from 75.23 to 102.62%, and the relative standard deviations were between 3.55 and 8.07% (< 10%). The method was used to analyze naturally contaminated positive feedstuff, and the results obtained by this method was in a good agreement with data obtained by immunoaffinity column-high-performance liquid chromatography (IAC-HPLC–FLD). The conformity and correlation of two methods was satisfactory. The comprehensive results showed that the proposed method was shown to be a suitable method for ZEN determination.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Highly thermally conductive but electrically insulating polymer composites play an increasingly important role in thermal management applications due to their features of easy processing and ...lightweight. Herein, a unique segregated network, which consists of graphene nanoplatelets (GNP) and boron nitride fibers (BNF), was constructed in polypropylene (PP)-based composites via two-screw extrusion. The thermal conductivity and electrical insulation characteristic of the composites could be well controlled by adjusting the content and size of GNP and BNF. When PP was filled with 9wt% GNP and 30wt% short BNF, the highest thermal conductivity of 1.32 W/(m·K) was achieved in this work, which is about six times higher than the value of neat PP, while remained a good electrical insulating (as low as 2.98 × 10
−9
S/m). It proposed that the unique segregated network, where the BNF play as a bridge to connect the scattered GNP, could benefit for phonons transmission but effectively interrupt electron conduction. Our work provides a facile method to design and fabricate the highly thermally conductive but electrically insulating composites applied in thermal management materials.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Aiming at the problems inherent in the traditional fuzzy energy management strategy (F-EMS), such as poor adaptive ability and lack of self-learning, a neural network fuzzy energy management strategy ...(NNF-EMS) for hybrid electric vehicles (HEVs) based on driving cycle recognition (DCR) is designed. The DCR was realized by the method of neural network sample learning and characteristic parameter analysis, and the recognition results were considered as the reference input of the fuzzy controller with further optimization of the membership function, resulting in improvement in the poor pertinence of F-EMS driving cycles. The research results show that the proposed NNF-EMS can realize the adaptive optimization of fuzzy membership function and fuzzy rules under different driving cycles. Therefore, the proposed NNF-EMS has strong robustness and practicability under different driving cycles.
Public transportation is often considered as a green travel mode to alleviate the negative externalities such as traffic congestion and haze pollution generated from transport. However, is ...prioritizing urban public transportation actually conducive to haze emission reduction? In this study, considering special emphasis on the cumulative effect of haze, a dynamic panel model is constructed to analyze and quantify the impact of public transportation on haze pollution by using the data of 284 cities in China, and the heterogeneity of the impact in cities with different pollution levels is examined. Several interesting findings are derived from the empirical results. First, the development of urban public transportation can significantly alleviate urban haze pollution. Second, the haze reduction effect of public transportation in cities with different pollution levels is non-universal. Comparatively speaking, the haze reduction effect of public transportation in lightly polluted cities is more evident than that in heavily polluted cities. Therefore, in order to reduce haze pollution in a more effective manner, China should continue to promote urban public transportation priority strategy. Moreover, the government should also formulate differentiated traffic development strategies to effectively alleviate the urban traffic burdens.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract Utilization of nanofibrous matrices for skin wound repair holds great promise due to their morphological and dimensional similarity to native extracellular matrix (ECM). It becomes highly ...desired to understand how various nanofibrous matrices regulate skin cell behaviors and intracellular signaling pathways, important to tuning the functionality of tissue-engineered skin grafts and affecting the wound healing process. In this study, the phenotypic expressions of normal human dermal fibroblasts (NHDFs) on collagen-containing nanofibrous matrices with either isotropic ( i.e., fibers collected randomly with no alignment) or anisotropic ( i.e., fibers collected with alignment) fiber organizations were studied by immunostaining, migration assay and molecular analyses. Results showed that both nanofibrous matrices supported the attachment and growth of NHDFs similarly, while showing different cell morphology with distinct variation in focal adhesion formation and distribution. Anisotropic nanofibers significantly triggered the integrin β1 signaling pathway in NHDFs as evidenced by an increase of active integrin β1 (130 kD mature form) and phosphorylation of focal adhesion kinase (FAK) at Tyr-397. Anisotropic matrices also promoted the migration of NHDFs along the fibers, while neutralization of the integrin β1 activity abolished this promotion. Moreover, the fibroblast-to-myofibroblast differentiation was greatly enhanced for the NHDFs cultured on anisotropic nanofibrous matrices over a period of 48 h. Inhibition of cellular integrin β1 activity by neutralizing antibody eliminated this enhancement. These findings suggest the important role of integrin β1 signaling pathway in regulating the nanofiber-induced fibroblast phenotypic alteration and providing insightful understanding of the possible application of collagen-containing nanofibrous matrices for skin regeneration.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Atherosclerosis is the main cause of carotid artery stenosis (CAS) which mostly occurs in the elderly. In this paper, the expression level of miR-375-3p in asymptomatic CAS patients and its ...diagnostic value for asymptomatic CAS were investigated, and the effects of miR-375-3p on the cell proliferation and migration of vascular smooth muscle cells (VSMCs) was further explored.
98 healthy subjects and 101 asymptomatic CAS patients were participated in this study. qRT-PCR was used to measure the expression level of serum miR-375-3p, and the ROC curve was established to evaluate the predictive value of miR-375-3p for asymptomatic CAS. After transfection with miR-375-3p mimic or inhibitor in vitro, cell proliferation and migration were detected by CCK-8 assay, colony formation assay, and Transwell assay, respectively. The levels of TNF-α, IL-1β, IL-6 were detected by ELISA. Western blot was used to detect the protein expression of XIAP. Finally, luciferase reporter gene assay was applied to assess the interaction of miR-375-3p with target genes.
The expression level of serum miR-375-3p in asymptomatic CAS patients was significantly higher than that in healthy controls, and the AUC value of ROC curve was 0.888. The sensitivity and specificity were 80.2 and 86.7%, respectively, indicating that miR-375-3p had high diagnostic value for asymptomatic CAS. In vitro cell experiments showed that up-regulation of miR-375-3p significantly promoted the proliferation and migration of VSMCs, and also promoted the generation of inflammatory factors and phenotypic transformation of VSMCs. Luciferase reporter gene assay confirmed that XIAP was a target gene of miR-375-3p and was negatively regulated by miR-375-3p.
In this study, miR-375-3p may have a clinical diagnostic value for asymptomatic CAS patients which need further validation. Increased miR-375-3p levels in CAS may be associated with increased proliferation and migration of VSMCs via downregulation of the apoptosis inducing gene XIAP.
Abstract Orientation of extracellular matrix (ECM) fibrils contributes to the anisotropy of bones, but little is known about how fibril orientation induces osteoblastic responses. Here, biomimetic ...polycaprolactone/type I collagen (PCL/COL-1) nanofibers with aligned and random fiber arrangements were used as models to study their effects on pre-osteoblasts. Elongated cell morphology, accelerated cell migration, elevated alkaline phosphatase activity and calcium content, up-regulated expression of osteogenic markers and differential expression of integrins were observed for cells cultured on two-dimensional (2D) aligned nanofibers. To emulate in vivo tissue structure, three-dimensional (3D) cell/nanofiber constructs with cells embedded among nanofiber layers were built via layer-by-layer assembly. These showed that aligned nanofibers in the 3D constructs continuously induced cell polarization and promoted osteogenesis. These findings revealed that nanofiber alignment favored osteogenic differentiation of pre-osteoblasts, and demonstrated the potential of 3D cell/nanofiber construct as a model to study specific cell-material interactions in a physiologically relevant environment. From the Clinical Editor In this novel study, biomimetic polycaprolactone/type I collagen nanofibers with aligned and random fiber arrangements were used to demonstrate their effects on pre-osteoblasts with an overall goal of improved orientation of extracellular matrix fibrils to optimize osteoblastic responses and improve osteogenesis for future therapeutic exploitation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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