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Platinum-based chemotherapy promotes drug resistance in ovarian cancer. We investigated the anti-chemoresistance characteristics of diallyl trisulfide (DATS) in cisplatin-resistant ovarian cancer cells, in vitro and in vivo. Previous preclinical studies have revealed that DATS regulates distinct hallmark cancer-signaling pathways. The cell cycle pathway is the most investigated signaling pathway in DATS. Additionally, post-DATS treatment has been found to promote proapoptotic capacity through the regulation of intrinsic and extrinsic apoptotic pathway components. In the present study, we found that treating cisplatin-sensitive and cisplatin-resistant ovarian cell lines with DATS inhibited their proliferation and reduced their IC

The numerical simulation is similar to the experimental research, which uses the computer. 3D printing is an experimental study, which is compared with simulation. 3D printing and precision casting of impellers are frequently used in industrial scenarios. To address the problem of low casting yield of aluminium alloy impellers in gypsum-type casting, three-dimensional modelling by magics, casting simulation, and parameter optimization method by applying ProCAST software are used to improve the casting yield of impellers. The results show that the optimized structure of the casting system is more reasonable, so that the shrinkage and shrinkage defects are concentrated in the location of the riser; the maximum stress value of the casting and the casing during the solidification stage is 2.71 MPa, which is much smaller than the stress limit of the casing; the maximum horizontal displacement of the casting along the X and Y axes after solidification is completed at 0.025 mm and 0.022 mm, respectively, and the maximum displacement along the Z axis due to the presence of the riser is 0.009 mm, which greatly improves casting accuracy and molding quality.

Background: Aberrant suppression of cytochrome P450 3A5 (CYP3A5) is frequently observed in human esophageal squamous cell carcinoma (ESCC); however, its role and the epigenetic mechanism mediating transcriptional repression of CYP3A5 in ESCC remain poorly understood.Results: Herein, we examined the expression and prognostic role of CYP3A5 in tumor tissues obtained from patients with ESCC. CYP3A5 silencing correlated with poor survival in ESCC. Using the histone deacetylase (HDAC) inhibitor trichostatin A (TSA), RNA interference, reporter gene assays, and chromatin immunoprecipitation, HDAC4 was found to be the key enzyme responsible for the absence of H3K18/K27Ac, mediated via P300/CBP at the CYP3A5 promoter. Finally, using CYP3A5 knockdown, re-expression, and xenograft experiments, we demonstrated that CYP3A5 downregulation, resulting in ZEB2 activation, promoted ESCC invasion and migration. Conclusions: our findings indicate that CYP3A5 activation reverses ZEB2-induced epithelial-mesenchymal transition (EMT) and inhibits migration and invasion of ESCC cells.

Here, light and ferric ion (Fe3+) responsive fluorochromic hydrogels with high strength and self-healing ability were designed and synthesized. The hydrogels were prepared via physical crosslinking of poly(vinyl alcohol) (PVA), in the presence of γ-cyclodextrin-spiropyran (γ-CD-SP) and tannic acid (TA). By utilizing the hydrogen bonding interaction between the γ-CD moiety and PVA chain, the fluorophore γ-CD-SP could be incorporated into the PVA gel successfully. Owing to photo-isomerization of the SP moiety, the hydrogel showed “on/off” fluorescence behavior upon ultraviolet/bright light irradiation. Moreover, the fluorescence emission of the hydrogel could also be turned off in the presence of Fe3+ by fluorescence inner filter effects, and then recovered by adding EDTA. The hydrogel possessed high tensile strength (i.e. 2.18 MPa) and self-healing ability. With the features of high strength, self-healing, and tunable fluorescence properties, the hydrogels would have potential applications in wearable devices, fluorescent sensors, and optical switches.

According to the idea of "Emerging Engineering Education" talent training model of Ministry of Education, students should be trained to have "metaphysical" concept, connection, imagination, macro thinking. Project-driven experiment teaching focuses on a project, and the goal is the completion of the project; the student is the center of teaching activities, which is supported by the inquiry process. This study analyzes the significance of the project-driven method in experimental teaching. This paper describes the implementation process of experimental teaching in the field of energy and power engineering in terms of project design, teaching system construction and so on under the project-driven method. By analyzing the results of a questionnaire survey distributed to students of energy and power in the College of Mechanical Engineering at the Tianjin University of Technology, it is found that the students are satisfied with the effects of project-driven experimental teaching, and the use of experimental teaching has greatly aroused the students’ enthusiasm for learning. The ability of the students to engage in autonomous learning, engineering practice and innovation has been greatly improved, and a good teaching effect has been achieved.

To reduce overall patient radiation exposure in some clinical scenarios (since cancer patients need frequent follow-ups), noncontrast CT is not used in some institutions. However, although less desirable, noncontrast CT could provide additional important information. In this article, we propose a deep subtraction residual network based on adjacency content transfer to reconstruct noncontrast CT from contrast CT and maintain image quality comparable to that of a CT scan originally acquired without contrast. To address the slight structural dissimilarity of the paired CT images (noncontrast CT and contrast CT) due to involuntary physiological motion, we introduce a contrastive loss network derived from the adjacency content-transfer strategy. We evaluate the results of various similarity metrics (MSE, SSIM, NRMSE, PSNR, MAE) and the fitting curve (HU distribution) of the output mapping to estimate the reconstruction performance of the algorithm. To build the model, we randomly select a total of 15,405 CT paired images (noncontrast CT and contrast-enhanced CT) for training and 10,270 CT paired images for testing. The proposed algorithm preserves the robust structures from the contrast-enhanced CT scans and learns the noncontrast attenuation pattern from the noncontrast CT scans. During the evaluation, the deep subtraction residual network achieves higher MSE, MAE, NRMSE, and PSNR scores (by 30%) than those of the baseline models (BEGAN, CycleGAN, Pixel2Pixel) and better simulates the HU curve of noncontrast CT attenuation. After validation based on an analysis of the experimental results, we can report that the noncontrast CT images reconstructed by our proposed algorithm not only preserve the high-quality structures from the contrast-enhanced CT images, but also mimic the CT attenuation of the originally acquired noncontrast CT images.

A line structured light sensor (LSLS) is generally constituted of a laser line projector and a camera. With the advantages of simple construction, non-contact, and high measuring speed, it is of great perspective in 3D measurement. For traditional LSLSs, the camera exposure time is usually fixed while the surface properties can be varied for different measurement tasks. This would lead to under/over exposure of the stripe images or even failure of the measurement. To avoid these undesired situations, an adaptive control method was proposed to modulate the average stripe width (ASW) within a favorite range. The ASW is first computed based on the back propagation neural network (BPNN), which can reach a high accuracy result and reduce the runtime dramatically. Then, the approximate linear relationship between the ASW and the exposure time was demonstrated via a series of experiments. Thus, a linear iteration procedure was proposed to compute the optimal camera exposure time. When the optimized exposure time is real-time adjusted, stripe images with the favorite ASW can be obtained during the whole scanning process. The smoothness of the stripe center lines and the surface integrity can be improved. A small proportion of the invalid stripe images further proves the effectiveness of the control method.

To develop hydrogels with high mechanical strength for cell encapsulation and three-dimensional culture is a critical challenge for cartilage tissue engineering. In this study, novel double network (DN) hydrogels were fabricated and phosphate buffer solution (PBS) was used as the solvent to facilitate cell encapsulation. The tough DN hydrogels were prepared through a two-step photopolymerization using neutral oligo(2,2-dimethyltrimethylene carbonate)–poly(ethylene glycol)–oligo(2,2-dimethyltrimethylene carbonate)–diacrylate (DPD–DA) chains for the first network and methacrylated hyaluronic acid (HA–GMA) chains for the second network. The fracture stress values of the optimized and cell-laden DN hydrogels were 8.38 ± 0.67 MPa and 6.28 ± 1.26 MPa, respectively, which showed comparable mechanical strength with natural articular cartilage tissue. The live/dead cell viability assay of cell-laden DN hydrogels demonstrated the tough DN hydrogels have comparable cytocompatibility with PEG hydrogels. After long-term culture, cartilage-specific extra cellular matrix accumulated in these DN hydrogels. The results indicated the potential of the novel DN hydrogels as cartilage tissue engineering scaffolds.

Objective Systematic reviews and meta-analyses have revealed the associations between H. pylori infection and various health outcomes. We aimed to evaluate the strength and breadth of evidence on the associations. Design Umbrella review of systematic reviews and meta-analyses. Setting No settings. Participants No patients involved. Data sources Embase, PubMed, Web of Science, Cochrane Library Databases, CNKI, VIP database and Wangfang database from inception to February 1, 2019. Outcomes measures Diverse diseases (such as cancer and ischaemic heart disease). Results Sixty articles reporting 88 unique outcomes met the eligible criteria. 74 unique outcomes had nominal significance (p75%). Moreover, 20% exhibited publication bias (p

Conventionally, each fluorophore is only clarified with the wavelength of incident beam shorter (down-conversion) or longer (up-conversion) than that of emission light. However, three anthracenes presented in this paper are the wavelength-focused (WF) molecules which can shift the portions of shorter and longer wavelengths of incident light into an identical wavelength in between. UV (ultraviolet) and NIR (near infrared) portions of Xenon light-simulated solar spectrum are focused into visible light with maximum wavelengths ranging from 415 to 471 nm through the two-way photoluminescence of the three anthracenes (anthracene (AN), fluoranthene (FLA) and 9, 10-diphenylanthracene (DPA)). At the same time, the intensity of the visible light is two times as that of excitation light. Besides, DPA dissolved in different solvents shows excellent fluorescence features. The results present great potential for applications in enhancing the intensity of solar spectrum at visible region and utilizing more portions of sunlight with solar cell.

Our synthesized oligomer (OCACP) can convert the near-infrared (NIR) region of sunlight into visible light with assistance from ultraviolet (UV) light, and the mechanism includes UV quantum cutting and NIR two-photon absorption. Here, we report a high conversion rate (ΦF = 0.4108) for a wavelength-focusing photoluminescent OCACP with densely grafted 2-pyrazoline that was prepared by free-radical polymerization of 3-carbethoxy-5-acrylatecarbethoxy-2-pyrazoline, a chromophore with good fluorescence (ΦF = 0.0171). After polymerization, the densely grafted 2-pyrazoline significantly increased the interaction between the pyrazoline ring and formed a propeller shape, and the intramolecular pyrazoline ring rotations were physically restricted, which restrained the non-radiative pathway and accelerated the radiative pathway. These factors collectively contributed to the excellent fluorescence performance of OCACP. Additionally, OCACP achieved good-quality live-cell imaging with an enhancement in the fluorescence intensity through two-wavelength excitation of the cell rather than increasing the dye dosage or laser power and improved the visible portion of sunlight for more efficient use of solar energy.

Tumor suppressor genes are frequently deleted or mutated in lung cancer. The RNA-binding motif protein 10 (RBM10) gene has the ability to suppress tumor activity, but the role of RBM10 during the development of lung cancer has yet to be elucidated. The current study investigated the expression levels of RBM10 in non-tumor and tumor tissues obtained from patients with adenocarcinoma using reverse transcription-polymerase chain reaction and western blot analysis, and identified a reduction in RBM10 expression in lung tumor tissue. To investigate the in vitro and in vivo function of RBM10, A549 human non-small cell lung cancer cells were transfected with the pcDNA-RBM10 vector. Flow cytometry was used to analyze the levels of apoptosis in the transfected cells. Western blot analysis was used to evaluate the expression of B-cell lymphoma 2 (Bcl-2), cleaved caspase-3, caspase-9 and poly (ADP-ribose) polymerase (PARP) proteins in A549 cells and tissues from the A549 xenograft Bagg Albino coat (BALB/c) nude mice model. RBM10 mRNA levels were significantly decreased in adenocarcinoma cells, but not in the non-tumor tissues. The A549 cells and tumor tissues exhibited significant growth inhibition following transfection with the pcDNA-RBM10 vector, which was determined using a cell proliferation assay. Flow cytometry analysis of cells stained with Annexin V/propidium iodide indicated that the overexpression of RBM10 induced apoptosis in A549 cells. The present study demonstrated that the expression levels of Bcl-2 protein were decreased and the expression levels of cleaved caspase-3, caspase-9 and PARP proteins were significantly increased in the A549 cells and cells from ex vivo tumor tissues that were injected with RBM10 vector-containing Salmonella enterica subspecies enterica serovar typhimurium. Notably, the current study identified that the accumulated and stable overexpression of RBM10 in the xenograft BALB/c nude mice model significantly inhibited the tumor growth rate. These results may provide novel insights into the use of RBM10 for lung cancer diagnosis and therapy.

The Ndiazo,C3-diradical of diazomethane (˙NN–H2C˙) is a resonance structure with 1,3-dipole form. And alkyl diazoacetate (ethyl diazoacetate, EDA) can interact with α,β-unsaturated aldehyde (cinnamaldehyde, CA) without any catalyst to compose the Ndiazo,C5- and Ndiazo,C8-diradicals, which are the building species to produce the copolymer of EDA with CA through a sequential series of Ndiazo,Cω-diradical intermediates.

The wavelength of incident light can be shifted by down-conversion (DC) and up-conversion (UC) photofluorescence. DC and UC molecules are typically independent one-way conversion species, and UC should be stimulated by a laser source. In this paper, we find that diazoacetate- and fumarate-containing fluorescent molecules are wavelength-focusing species of simulated solar radiation. Monochromatic UV and NIR lights (354/696, 457/819 or 346/686 nm) are synchronously focused to 454, 473 or 454 nm, respectively, using (5R)-5-cyano-3-carbmenthoxy-2-pyrazoline, 3-carbethoxy-2-pyrazoline grafted polyvinyl alcohol and a cyclic oligomer of ethyl diazoacetate with carbethoxy carbene and allyl acrylate. With a broadband light source, portions of the 300–500 nm and 580–800 nm wavelength bands of incident light are synchronously converted to 507 nm using a copolymer of PEG and fumarate, which offers a promising way to harvest the UV and NIR portions of sunlight in the visible region.

Background/Aims: Colorectal cancer (CRC) is the third most common type of cancer worldwide. Sprouty proteins are modulators of mitogeninduced signal transduction processes and therefore can influence the process of cancerogenesis. The encoded protein of Sprouty homolog 4 (SPRY4) is associated with various human cancers. However, its biological role and clinical significance in CRC development and progression are unknown. Methods: The aim of this study was to evaluate the expression and biological role of SPRY4 in colorectal cancer. qRT-PCR was performed to investigate the expression of SPRY4 in tumor tissues and corresponding non tumor colorectal tissues from 70 patients. The effect of SPRY4 on proliferation was evaluated by MTT and colony formation assays. CRC cells transfected with SPRY4 were injected into nude mice to study the effect of SPRY4 on tumorigenesis in vivo . Results: The lower expression of SPRY4 was remarkably correlated with deep tumor invasion and advanced TNM stage. Multivariate analyses revealed that SPRY4 expression served as an independent predictor for overall survival. Using 5-aza treatment, we also observed that SPRY4 expression can be affected by DNA methylation. Further experiments revealed that overexpressed SPRY4 significantly inhibited CRC cell proliferation both in vitro and in vivo . Conclusion: Our study demonstrated that SPRY4 is involved in the development and progression of colorectal cancer by regulating cell proliferation and shows that SPRY4 may be a potential diagnostic and prognostic target in patients with colorectal cancer.

Copolymerization between alkyl diazoacetates and α,β-unsaturated aldehydes, which is a one-pot, one-step and catalyst-free reaction, is presented. The product is a ternary copolymer composed of an alkyl diazoacetate, an α,β-unsaturated aldehyde and an α-carbalkoxy carbene, which is derived from the alkyl diazoacetate by the release of N2. Thus, the reaction is named as the C1N2/C2/C1 copolymerization. Various diazoacetates and α,β-unsaturated aldehydes were utilized to establish the methodology. The products are down-/up-conversion fluorescence molecules that can significantly enhance cell imaging through the synchronized excitation of near-ultraviolet and near-infrared light and may be widely used in other optical fields. The up-conversion fluorescence is the result of a two-photon excitation process.

Rationale: Primary gastric inflammatory myofibroblastic tumor is extremely rare. Only a few cases were reported in the domestic and foreign medical literature with corresponding imaging findings of this disease even more rarely reported. Patient concerns: We present one case of a 52-year-old female patient with upper abdominal pain, acid reflux, and belching for 2 months. Diagnoses and Interventions: Electron ultrasound gastroscopy (EUS) revealed elevation of gastric antrum mucosa. A whole abdominal and pelvic multi-slice spiral computed tomography (CT) detected a round nodule in the gastric antrum with considerably delayed enhancement, with initial suspicion of gastrointestinal stromal tumors (GISTS). Then a laparoscopic assisted distal gastrectomy was performed. Finally, the postoperative pathology confirmed the diagnosis of primary gastric IMT. Outcomes: After 6 months of follow-up, the patient was still alive without any evidence of metastasis or recurrence. Lessons: Familiarizing with the CT features of this rare tumor may raise radiologists’ awareness of the disease and potentially could avoid misdiagnosis.

A metalloenzyme-inspired polymeric palladium catalyst, which was prepared by self-assembly of a polymeric imidazole ligand with PdCl2, promoted carbene polymerization with high catalytic activity and reusability. Besides the atactic polycarbethoxycarbene (PCEC), a small amount of stereoregular PCEC was also obtained with poly(imidazole-Pd)-mediated polymerization of ethyl diazoacetate (EDA). This is the first example that a stereoregular polycarbene in an isolated form is obtained with a palladium-initiating system, suggesting that the steric polymeric imidazole ligand could affect the carbene insertion process. Detailed end group analyses on the obtained atactic and stereoregular PCEC revealed the chain initiation and chain termination mechanisms. XPS analyses on the oxidation state changes of the palladium center exhibited that PdII was reduced to PdI, which suggests that an intramolecular electron transfer process occurred during the interaction of palladium and EDA. Kinetic studies showed a zero order kinetic dependent on the concentration of EDA, which indicates a strong binding of EDA on the catalyst preceding carbene formation. With the addition of a radical inhibitor, the reaction rate was found to be greatly decreased. In the presence of a spin trap, a striking electron paramagnetic resonance (EPR) spectrum could be detected, which suggests the involvement of radical intermediates. DFT calculations on the proposed Pd-carbene radical species supported the EPR analyses, which assigned a significant amount of spin density on the carbene-carbon atom. Based on these results, we proposed an unprecedented metal-carbene radical polymerization mechanism, which occurs through a stepwise carbene radical migration and insertion process to afford polycarbenes.

Poly(imidazole-Cu)-mediated C1/C1N2 copolymerization of ethyl diazoacetate involved copper-based carbene radical and α-carbonyl diazomethane radical intermediates, which could be captured by radical traps and detected by room-temperature EPR spectroscopy. The obtained C1/C1N2 copolymer could be used as a new kind of upconversion agent for the non-invasive bioimaging study.

Abundant research efforts have been devoted to meet the demands for high-strength hydrogels in biomedical applications. Double-network (DN) hydrogels and homogeneous hydrogels are two typical samples. In this study, a novel ultra-strong and resilient double macromolecular network (DMMN) hydrogel system has been developed via a two-step sequential cross-linking process using hyaluronan (HA) and high molecular weight poly(ethylene glycol) (PEG) for the first and second network, respectively. A lower concentration of the HA precursor solution and a higher concentration of the PEG precursor solution as well as a higher molecular weight of the PEG precursor are beneficial to produce high-strength DMMN gels. Dynamic light scattering measurements demonstrate that DMMN gels possess the more evenly distributed polymer networks; the distinctive double and relatively evenly distributed networks of the DMMN gel make it combine the current DN and homogeneous network strategies for preparing robust hydrogels. The optimized DMMN gel is capable of sustaining up to 50 MPa of compressive stress. Besides, DMMN gels exhibit excellent cytocompatibility. This study expands the DN principle in designing and fabricating high-strength hydrogels with biocompatible macromolecules that show a promising prospect for biomedical applications. Published version

Conventionally, each fluorophore is only illuminated with the wavelength of incident light shorter (downconversion) or longer (upconversion) than that of emitted light. However, the oligopyrazolines presented in this paper are the down- and upconversion fluorescent molecules with a maximum emission at 445 nm, which are facilely synthesized from diazoacetates and maleic anhydride (MA) without any catalyst by a newly developed one-pot process. The intermediates of oligopyrazolines are formed through 1,3-dipolar cycloaddition and a cascade ring-opening insertion, which transform into oligomers in situ with molecular weight around 2 × 103 g mol−1. The structures of the subunits and resulting oligopyrazolines are clarified clearly by MALDI-TOF-MS and the quantum yield with excitation at 350 nm is in the range of 12–19%. A cell experiment with HeLa cells demonstrates its promising potential for bioimaging applications.

This paper design a safe positioning and remote network monitoring terminal system, using MCU microcontroller and UM220-III, and UM220-III is the decoding module of GPS/beidou dual-mode satellite signal. The design uses the STC89C52 chip as the main control MCU chip, and realizes real-time acquisition of the position, speed and time information of the monitoring object by the UM220-III module, and controls the wireless communication module M590E to send the collected information to the remote network server terminal. The design uses Java technology to develop remote network server terminal program, and it realizes the processing, storage, and display combined with the online map on the remote network monitoring platform for the received data. When inputting the specified address in the browser window of the Internet device and correctly logging in the user account and password, the remote network monitoring platform interface can be loaded on the webpage, and the current position and historical movement trajectory of the monitored object are accurately displayed on the platform. Whether the monitored object is in the safe area is marked with a warning light. The test results show that the technical scheme is feasible, the system is stable and can achieve the effect of safe positioning and remote monitoring, the man-machine interface is friendly, and the design has great practical significance.

Beidou and GPS are an important part of the GNSS (Global Navigation Satellite System). Beidou is a global satellite navigation system that is independent development and operation in China. GPS is the most mature development system in the world currently. The research on the Beidou/GPS multi-mode receiver has an important practical significance at present. Compared with hardware receiver, software receiver realizes the performance of the receiver by software, and is suitable for developing new algorithms. Therefore it has advantages of flexibility, convenience, and low costs. A method to realize the baseband signal processing of the Beidou/GPS multi-mode receiver is introduced in this paper by using the chip EP2S90F1020I4, which is Stratix II series of Altera's FPGA. Using Verilog HDL to design the baseband processing module of Beidou/GPS, including the fast acquisition module and tracking channel processing module, and the tracking channel processing module includes the carrier/code NCO generation module, the complex phase rotation DDC (Digital Down Converter) module, the Beidou/GPS pseudo-random code generator, code correlator module and frame synchronization module, etc. Test results show that the baseband signal processing module based on FPGA with the DSP calculation module can achieve the normal PVT calculation.

With the development of the integration of global economic and the technology of computer & communication, the ability of data acquisition and transmission in real-time is required in the logistics monitoring system. To reduce the server operating pressure in logistics management as well as the cost, a logistics monitoring terminal is designed based on Nios II soft-core and Beidou/GPS dual-mode module. The control core, FPGA of Intel PSG, of the system is embedded by Nios II whose CPU grade and peripherals can be customized as needed with better performance in low power consumption. The position solution chip of the presented terminal is based on a UM220-nI module, which is a large-scale integrate with low power consumption of the Beidou/GPS dual-mode positioning module. Nios II soft-core processor receives the NMEA-0183 data through a UART port and extracts the information such as longitude, latitude, velocity and UTC time, etc. The position information is converted locally and sent by the SIM900A module, say, the temperature and humidity monitored by the terminal sensors, to the specified server through GPRS. The useful monitoring data is transmitted directly by the logistics monitoring terminal. It can greatly reduce the amount of data transmission, the amount of data processed by the server, the pressure of logistics management server and the cost of the system; and can also simplify the control operation and improve the transmission efficiency of GPRS. The results indicate that, during the combinative test of the monitoring terminal and the B/S monitoring platform, the operation of the system is stable and the data can be displayed in real-time. It also shows that the monitoring terminal has the advantages of high performance and low power consumption that has an important application prospects.

Laser stripe center extraction is a key step for the profile measurement of line structured light sensors (LSLS). To accurately obtain the center coordinates at sub-pixel level, an improved gray-gravity method (IGGM) was proposed. Firstly, the center points of the stripe were computed using the gray-gravity method (GGM) for all columns of the image. By fitting these points using the moving least squares algorithm, the tangential vector, the normal vector and the radius of curvature can be robustly obtained. One rectangular region could be defined around each of the center points. Its two sides that are parallel to the tangential vector could alter their lengths according to the radius of the curvature. After that, the coordinate for each center point was recalculated within the rectangular region and in the direction of the normal vector. The center uncertainty was also analyzed based on the Monte Carlo method. The obtained experimental results indicate that the IGGM is suitable for both the smooth stripes and the ones with sharp corners. The high accuracy center points can be obtained at a relatively low computation cost. The measured results of the stairs and the screw surface further demonstrate the effectiveness of the method.

Catalyst-free copolymerization of ethyl diazoacetate (EDA) with carbethoxycarbene (CEC) has been achieved through two approaches: microwave irradiation and enzyme-assisted (Novozyme-435) system. The structure of the copolymer was characterized by MALDI-TOF MS ( m/z from 2000 to 2450), which suggested that the main chain of the copolymer consisted of CH(COOEt) and N N–CH(COOEt) frameworks. Fourier transform infrared (FTIR) spectrometry, elemental analysis, and Raman spectrometry proved the incorporation of azo group in the copolymer. The results indicated that the CEC radicals were generated under microwave irradiation (with or without Novozyme-435) from EDA. The mechanism study described that the generation speed of CEC radical was faster than its polymerization, and the excess CEC radicals improved the activity of the N2C1 group, thus inducing some EDA molecules as radicals. The two kinds of radicals co-coupled to result in poly(CEC- co -EDA) through the C1/N2C1 copolymerization, but the homopolymerization of CEC radical occurred quicker than its co-coupling with activated EDA.

The aim of the present study was to evaluate the value of diffusion-weighted imaging (DWI) and water imaging combined with dynamic contrast-enhanced scanning for the preoperative diagnosis and staging of rectal cancer. In total, 72 patients with pathologically confirmed rectal cancer were selected for examination using magnetic resonance imaging (MRI) with phased-array coils, DWI, water imaging and dynamic contrast-enhanced scanning. The patients were divided into two groups, experimental (simple enhanced scanning plus diffusion combined with water imaging) and control (simple enhanced scanning), for the pathological observations. The sensitivity, specificity and accuracy for the T staging of the carcinomas using scan enhancement with DWI and the evaluation of cancer using water imaging were 98.5% (65/66), 66.7% (4/6) and 95.8% (69/72), respectively, and the accuracy for N staging was 89%. Whereas, the sensitivity, specificity and accuracy for the T staging of the carcinomas using simple scan enhancement were 85.7% (42/49), 78.3% (18/23) and 83.3% (60/72), respectively, and the accuracy for N staging was 61%. Therefore, the combination of multiple MRI techniques may be of high value for the early diagnosis and exact staging of rectal cancer.

Kinetic studies of the carbene polymerization of ethyl diazoacetate (EDA) by palladium (Pd) or rhodium (Rh) catalysts were investigated by real-time Fourier transform infrared (FTIR) spectroscopy. Both (L-prolinate)RhI(1,5-cyclooctadiene) and (L-prolinate)RhI(2,5-norbornadiene) mediated EDA polymerization were proved to be first order reactions, suggesting that the formation of “Rh-carbenoid” is the rate determining step. The activation energy (11.24 kJ mol−1) of the polymerization of “carbenes” generated from EDA with (L-prolinate)RhI(1,5-cyclooctadiene) as the catalyst was calculated from kinetic data via the Arrhenius equation. On the other hand, the polymerizations of EDA catalyzed by three kinds of Pd-catalysts were revealed as zero order reactions, suggesting that the rate determining step involves the formation of an EDA–Pd transition state complex through a coordinated step. Refilling more EDA to the (bis(acetonitrile)dichloropalladium)-mediated carbene polymerization system did not change the reaction order. The rate constant increases gradually with the increase of the dosage of the catalyst and decreases with the cycle-index, which proves the formation of “EDA–Pd transition state complex” and the propagating species with Pd–C bonds at the end of the polymer chain.

The present contribution describes an innovation in the copolymerization of cyclic monomers, e-caprolactam (e-CL) and 2,2-dimethyltrimethylene carbonate (DTC), with ethyl diazoacetate (EDA). The characterizations of the obtained copolymers, poly(EA-ran-EDA-ran-e-CL) and poly(EA-ran-EDA-ran-DTC) (where EA refers to the ethyl acetate group from EDA after nitrogen release), were performed using 1H NMR and 13C NMR spectroscopies and size exclusion chromatography. Under optimized conditions, the copolymer of e-CL with EDA possessing a number-average molar mass (Mn) of 1300 g mol−1 and dispersity of 2.12 as well as that of DTC with EDA with Mn of 8000 g mol−1 and dispersity of 1.47 were obtained. The incorporation of the azo group in the obtained copolymers was determined from the results of elemental analysis (3.30–10.22% nitrogen) and Fourier transform infrared spectroscopy. Furthermore, the thermal properties of the obtained copolymers were examined using differential scanning calorimetry. X-ray diffraction results showed that the synthesized copolymers were amorphous. © 2014 Society of Chemical Industry

Polypyrazoles with molecular weights in the range of 6500–9300 g mol−1 and yields in the range of 71.4–82.5% were synthesized successfully by catalyst-free 1,3-dipolar cycloaddition of bisdiazo compounds to bisalkynes under thermal conditions and lost merely 5% of their weights at temperatures higher than 298 °C. The porous polypyrazole–copper complex with pore diameters in the range of 1–2 μm was prepared by the coordination of polypyrazole and copper sulfate (CuSO4), which is a reusable catalyst for the Huisgen 1,3-diploar cycloaddition of alkynes and organic azides to give the corresponding triazoles with yields over 90%.

Aberrant expression of microRNAs (miRNAs) has been widely recognized to play critical roles in the pathogenic processes of colon cancer. However, the expression and functions of miR-3653 in colon cancer remain uncovered. This study revealed for the first time that miR-3653 expression was significantly decreased in colon cancer tissues and cell lines. MiR-3653 overexpression led to decreased migration and invasion of HCT116 cells while miR-3653 knockdown resulted in opposite influence of the metastatic behaviors of HT29 cells. qRT-PCR and western blot demonstrated that miR-3653 suppressed the epithelial-mesenchymal transition (EMT) of colon cancer cells using both gain- and loss- of function assay. Mechanically, miR-3653 was found to interact with the 3'-UTR of Zeb2 through the complementary sequences and inhibited the expression of Zeb2 in colon cancer cells. Rescue experiments demonstrated that the inhibitory effect of miR-3653 overexpression on cell metastasis and EMT was abrogated by forced expression of Zeb2. This study demonstrates that miR-3653 suppresses the metastasis and EMT of colon cells by targeting Zeb2, and serves as a promising biomarker and therapeutic target in colon cancer.

By analyzing the relationship between urban road transportation energy demand and economy and passenger transportation, the dynamic model of road transportation energy demand system in Beijing is built, and the road transportation statistics are applied to the system anyway. The results show that the system can overcome the shortcomings of road transportation forecasting, and verify the feasibility of the system. It has decision-making reality and predictability for the analysis of road transportation energy demand.