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Currently, the national expressway has more than 120,000 kilometers, ranking first in the world. Unfortunately, the attendant problems such as the traffic congestion, traffic accidents, environmental pollution, and other negative effects also increased rapidly almost day by day. In this article, the mesoscopic traffic flow simulation model has been improved by inputting the expressway data. The estimated method of the expressway network running state is proposed, which takes approach proportion, or choice probability of intersection movements, as input information. Upon the designed mesoscopic traffic simulation process, the traffic accidents detection method is put forward under the condition of lacking the real-time data on road. The real expressway network of Shandong province and the toll data are used to test the validity of the proposed method. The results show that the proposed model and method can be more accurate in estimating the real-time network running state and the relevant macroparameters, such as the traffic flow speed, the averaged density, and flow. It is also feasible and effective to detect traffic accidents on road sections of the network. The proposed model and method can help expressway management department publish information, lay detectors, and conceal accident cover-up by the subordinate departments. [ABSTRACT FROM AUTHOR]

Breast cancer, with unsatisfactory survival rates, is the leading cause of cancer‐related death in women worldwide. Recent advances in the genetic basis of breast cancer have benefitted the development of gene‐based medicines and therapies. Tissue engineering technologies, including tissue decellularizations and reconstructions, are potential therapeutic alternatives for cancer research and tissue regeneration. In our study, human breast cancer biopsies were decellularized by a detergent technique, with sodium lauryl ether sulfate (SLES) solution, for the first time. And the decellularization process was optimized to maximally maintain tissue microarchitectures and extracellular matrix (ECM) components with minimal DNA compounds preserved. Histology analysis and DNA quantification results confirmed the decellularization effect with maximal genetic compounds removal. Quantification, immunofluorescence, and histology analyses demonstrated better preservation of ECM components in 0.5% SLES‐treated scaffolds. Scaffolds seeded with MCF‐7 cells demonstrated the process of cell recellularization in vitro, with increased cell migration, proliferation, and epithelial‐to‐mesenchymal transition (EMT) process. When treated with 5‐fluorouracil, the expressions of stem cell markers, including Oct4, Sox2, and CD49F, were maximally maintained in the recellularized scaffold with decreased apoptosis rates compared with monolayer cells. These results showed that the decellularized breast scaffold model with SLES treatments would help to simulate the pathogenesis of breast cancer in vitro. And we hope that this model could further accelerate the development of effective therapies for breast cancer and benefit drug screenings. In our study, human breast cancer biopsies were decellularized by the detergent technique with sodium lauryl ether sulfate (SLES) solution for the first time. Scaffolds seeded with MCF‐7 cells demonstrated the process of cell recellularization in vitro, with increased cell migration, proliferation, and epithelial‐to‐mesenchymal transition (EMT) process. When treated with 5‐fluorouracil (5‐Fu), the expressions of stem cell markers, including Oct4, Sox2, and CD49F, were maximally maintained in the recellularized scaffold with decreased apoptosis rates compared with monolayer cells. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is a leading cause of cancer‐related death in women with unsatisfactory survival rates. Advances in the understanding of the genetic basis of BC provide the opportunity to develop gene‐based medicines capable of treating metastatic diseases. Here, we first demonstrated efficient tissue engineering approaches applied to normal breast and BC extracellular matrix (ECM) starting from decellularized human biopsies to generate a three‐dimensional (3D) bioactive model with the sodium lauryl ether sulfate solution. The decellularized tissues maximized the genetic component removal from tissues and minimally injured ECM structures and native compositions by histology and ECM compositions analyses. Importantly, we proved that the 3D ECM retained tissues biological properties. We demonstrated that after 30 days of recellularization with MCF‐7 cell (human breast adenocarcinoma cell line), the 3D cancer ECM induced an overexpression of epithelial–mesenchymal transition (EMT) and cancer proliferation. Meanwhile, normal ECM from the breast inhibited EMT and cell growth with the inducement of apoptosis. Given the biological activity preserved in the ECM after decellularization, we believe these approaches are powerful tools for future preclinical research for BC and breast development. The decellularized tissues of normal human breast tissues and cancer tissues maximized the genetic component removal from tissues and minimally injured extracellular matrix (ECM) structures and native compositions. After 30 days of recellularization with MCF‐7 cell, the three‐dimensional cancer ECM induced an overexpression of epithelial–mesenchymal transition (EMT) and cancer proliferation. Meanwhile, normal ECM from breast inhibited EMT and cell growth with the inducement of apoptosis. [ABSTRACT FROM AUTHOR]

Key message: WUSCHEL-RELATED HOMEOBOX 11 establishes the acquisition of pluripotency during callus formation and accomplishes de novo shoot formation by regulating key transcription factors in poplar.Abstract: De novo shoot regeneration is a prerequisite for propagation and genetic engineering of elite cultivars in forestry. However, the regulatory mechanism of de novo organogenesis is poorly understood in tree species. We previously showed that WUSCHEL (WUS)-RELATED HOMEOBOX 11 (PtWOX11) of the hybrid poplar clone 84K (Populus alba × P. glandulosa) promotes de novo root formation. In this study, we found that PtWOX11 also regulates de novo shoot regeneration in poplar. The overexpression of PtWOX11 enhanced de novo shoot formation, whereas overexpression of PtWOX11 fused with the transcriptional repressor domain (PtWOX11-SRDX) or reduced expression of PtWOX11 inhibited this process, indicating that PtWOX11 promotes de novo shoot organogenesis. Although PtWOX11 promotes callus formation, overexpression of PtWOX11 and PtWOX11-SRDX also produced increased and decreased numbers of de novo shoots per unit weight, respectively, implying that PtWOX11 promotes de novo shoot organogenesis partially by regulating the intrinsic mechanism of shoot development. RNA-seq and qPCR analysis further revealed that PtWOX11 activates the expression of PLETHORA1 (PtPLT1) and PtPLT2, whose Arabidopsis paralogs establish the acquisition of pluripotency, during incubation on callus-inducing medium. Moreover, PtWOX11 activates the expression of shoot-promoting factors and meristem regulators such as CUP-SHAPED COTYLEDON2 (PtCUC2), PtCUC3, WUS and SHOOT MERISTEMLESS to fulfill shoot regeneration during incubation on shoot-inducing medium. These results suggest that PtWOX11 acts as a central regulator of the expression of key genes to cause de novo shoot formation. Our studies further provide a possible means to genetically engineer economically important tree species for their micropropagation. [ABSTRACT FROM AUTHOR]

The fast-growing cyanobacterium Synechococcus elongatus UTEX 2973 (hereafter Synechococcus 2973) has been considered a good chassis candidate for “microbial cell factory” as it can perform oxygenic photosynthesis and its doubling time can be as short as 1.9 h. However, the limited genetic tools currently restrict its further research and application efforts using synthetic biology approaches. In this study, a series of genetic tools were systematically developed and optimized for Synechococcus 2973. First, the introduction of Tfp pilus assembly protein encoding gene pilN into Synechococcus 2973 successfully recovered its natural transformability, which greatly simplified the DNA transformation process. Second, a series of promoters with different strengths were evaluated and the super-strong promoters including P cpc560 from Synechocystis sp. PCC 6803, native P psbA2 and P psbA3 of Synechococcus 2973 were found with the highest activity of β -galactosidase among those evaluated by miller values. Some promoters related to photosystems (i.e., P psbA2 , P psbA3 , P 6803psbA2 and P cpc560 ) were also demonstrated to be induced by high intensity of light. Third, three lactose induction systems were evaluated, among which P lac combined with lacI q showed the best application prospect with great induction capacity, low leakage and middle induced expression. Fourth, the translational on riboswitch theoE*  , the transcriptional off riboswitches theo/yitJ and xpt(C74U)/metE and an artificial inducing system combining theoE*  with T7 RNA polymerase were successfully developed and characterized in Synechococcus 2973. Finally, by using T7 induction system to control the expression of both small RNA and chaperone Hfq, a small RNA regulatory tool was developed and optimized to be a strictly inducible off system for gene regulation in Synechococcus 2973. The work here presented valuable genetic toolboxes necessary for metabolic engineering and synthetic biology research in Synechococcus 2973, which will facilitate the future application of the fast growing cyanobacterial chassis. [ABSTRACT FROM AUTHOR]

The survival rate of vitrified-thawed ovarian tissues after autotransplantation still needs to be improved. Therefore finding an ideal cryoprectant to reduce the damage to ovaries that caused by vitrification will pave the way for application of ovary cryopreservation on clinics. Experiments were conducted to investigate the effect of sodium alginate in cryoprotectant solution on mouse ovaries during the vitrification process. The ovaries obtained from 6-weeks old CD1 were assigned into six groups from A to F. Group A without treatment was used as the normal control. Group B cryopreserved with the basic cryoprotectant solution containing 15% each Me 2 SO and EG was used as the experimental control. Groups C, D, E, and F cryopreserved with the basic cryoprotectant solution supplemented with 0.05%, 0.10%, 0.15%, and 0.20% of sodium alginate, respectively, were assigned for the experimental groups. The in vitro analyses showed that the developmental capability of the oocytes isolated from vitrified-thawed ovaries significantly increased with increasing concentration of sodium alginate in the cryoprotectant solution (groups: A = 70 ± 2; B = 43 ± 2; C = 48 ± 3; D = 53 ± 3; E = 60 ± 3; B < C < D < A, P < 0.05), and reached its highest level in group E with 0.15% of sodium alginate (P < 0.05). The lowest developmental capability of all groups was group F (41 ± 1%)(P < 0.05) with 0.20% of sodium alginate. The similar results were obtained by the autotransplantation in vivo . These finding demonstrated that sodium alginate can significantly reduce the damage to ovaries by vitrification. [ABSTRACT FROM AUTHOR]

Introduction: Abnormal expression of microRNAs (miRNAs) contributes to cancer development through regulating proliferation, apoptosis and drug resistance in cancer cells. The present study was designed to explore the effect and mechanism of miR-141 on gastric cardia adenocarcinoma (GCA).Material and Methods: Forty-one paired GCA tissues and adjacent normal tissues were obtained from GCA patients never treated by chemotherapy or radiotherapy. QRT-PCR was used to detect the expression level of miR-141 in GCA. Effects of miR-141 on cell proliferation and apoptosis were detected in vitro. Western blot analysis was used to determine the downstream targets of miR-141.Results: In the present study, our data showed that miR-141 was significantly decreased and correlated with advanced TNM stage and lymph node metastases in GCA. In addition, we found that miR-141 could inhibit cell proliferation and induce cell apoptosis in AGS cells. Moreover, MACC1 was predicted as a possible target of miR-141. The luciferase reporter assay proved that miR-141 could suppress MACC1 directly by binding to its 3'-UTR. Further studies showed that miR-141 influenced the MEK/ERK and p38 MAPK signaling pathways.Conclusions: Our findings demonstrated that miR-141 expression was associated with GCA progression. MACC1, working as one possible target of miR-141, may contribute to the process. MiR-141 is expected to be a potential therapeutic target for the treatment of GCA patients. [ABSTRACT FROM AUTHOR]

We present an improved scheme for coherent beam combination using a type of non-separable phase-controlled Dammann grating (NPDG), which is capable of generating multiple equal-intensity diffraction orders with good uniformity and high efficiency in the far field. Compared with conventional separable two-dimensional (2D) Dammann gratings, the efficiency of such gratings is significantly improved around 10% due to the non-separable structure. Such improvement in the diffraction efficiency is of high significance for coherent laser combination. Furthermore, the phases of those diffraction orders for this type of gratings are only two-valued in the far field, which leads to a great simplification of phase matching during the procedure of coherent beam combination. As an example, a 5 × 5 NPDG with efficiency of 73.6% is theoretically designed and a NPDG sample with efficiency as high as 66.8% is experimentally fabricated by lithography and wet-etching techniques. Also, we implemented further a proof-of-principle experiment for coherent beam combination based on the 5 × 5 NPDG sample, and the results show that the combining efficiency is as high as 65.7%. [ABSTRACT FROM AUTHOR]

Hydrogels, promising biological materials, need to have both strong mechanical properties and also inherent self-healing properties. In this work a double cross-linked network (DN) hydrogel was designed and prepared by combining a Diels-Alder click reaction and coordination effects. This DN hydrogel had good thermodynamic properties, anti-EDTA performance and self-healing properties. In addition, the mechanical properties, swelling properties and surface morphology of DN hydrogels can be controlled by adjusting the ratio of Fe 3 + -catechol. The adjustment of pH value can change the color, crosslinking mode and mechanical properties of the DN hydrogel. This smart hydrogel created from DA click chemistry and coordination effects has significance for guiding the design of new hydrogels with good mechanical properties, self-healing properties and controlled cross-link density. [ABSTRACT FROM AUTHOR]