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Background Epithelial-mesenchymal transition (EMT) and anoikis are initial and pivotal steps during the metastatic process. Although higher levels of Nrf2 are associated with aggressive tumor behaviors such as proliferation, invasion and migration in cervical cancer, the detailed mechanism of Nrf2 in cervical cancer metastasis, especially EMT and anoikis, remains unclear.Methods We investigated the expression of Nrf2 in patients with or without cervical cancer lymph node metastasis through immunohistochemistry (IHC). Wound healing assay and transwell analysis were used to evaluate the migration ability of different cervical cancer cells including Nrf2 knockout and Nrf2 overexpression cells. Western blot was used to verify the expression level of Nrf2, the EMT associated markers and anoikis associated proteins in different situations. Flow cytometry assays were used to detect the apoptosis of cervical cancer cells. A xenograft assay was used to verify the metastatic function of Nrf2 in vivo.Results Nrf2 was highly expressed in patients with cervical cancer lymph node metastasis. And Nrf2 was proved to enhance the migration ability of HeLa and SiHa cells. In addition, Nrf2 was positively correlated with EMT processes and negatively associated with anoikis in cervical cancer through Snail1-dependent pathway. In vivo, a xenograft assay also showed that Nrf2 facilitated both pulmonary and lymphatic distant metastasis of cervical cancer.Conclusion Nrf2 could play a crucial role in the metastasis of cervical cancer by enhancing EMT and resistance to anoikis by promoting the expression of Snail1.

Since 2012, Xu and Zhou have reported the isolation of a series of gymnotheligans, a large group of novel tetrahydrofuran-containing lignan natural products. In the past decade, considerable achievements in the total syntheses of these lignans have been achieved based on a plausible biogenetic pathway proposed by our group in 2014. In this account, we summarize these remarkable synthetic works of the past ten years.1 Introduction2 Biogenetic Pathways to Gymnothelignans3 Total Syntheses of Eupodienones4 Total Syntheses of Eupomatilones5 Total Synthesis of Dibenzocyclooctenes6 Conclusions

Hydrous hydrazine (N2H4·H2O) has great potential as a convenient and safe hydrogen source for fuel cells. Tremendous efforts have been made to develop economic and efficient metal catalysts for hyd...

Dissemination of ovarian cancer (OvCa) cells can lead to inoperable metastatic lesions in the bowel and omentum, which have a poor prognosis despite surgical and chemotherapeutical options. A better understanding of the mechanisms underlying metastasis is urgently needed. In this study, bioinformatics analyses revealed that UBE2E2, a less-studied ubiquitin (Ub)-conjugating enzyme (E2), was upregulated in OvCa and was associated with poor prognosis. Subsequently, we performed western blot analysis and IHC staining with 26 HGSOC and 26 normal ovarian tissue samples, which further confirmed that UBE2E2 protein is highly expressed in OvCa tissue but almost not expressed in normal tissue. Furthermore, the silencing of UBE2E2 blocked OvCa cell migration, epithelial-mesenchymal transition (EMT) and metastasis in vitro, whereas UBE2E2 overexpression exerted the opposite effects. Mechanistically, UBE2E2 promoted p62 accumulation and increased the activity of the Nrf2-antioxidant response element (ARE) system, which ultimately activated the Snail signaling pathway by inhibiting the ubiquitin-mediated degradation of Snail. Furthermore, our results confirmed that mutations in the active site cysteine (Cys139) impaired both the function and cellular distribution of UBE2E2. More importantly, the deletion of UBE2E2 reduced tumorigenicity and metastasis in a xenograft ovarian cancer mouse model. Taken together, our study findings reveal the role of the UBE2E2-Nrf2-p62-Snail signaling axis in OvCa and thus provides novel therapeutic targets for the prevention of metastasis in OvCa.

In this work, mesoporous N-doped carbon (MNC) materials have been successfully prepared by a nanocasting route using SBA-15 as the template and ethylenediamine (EDA) and carbon tetrachloride (CTC) as carbon nitride precursors. The specific surface area and pore size of the MNC, as well as the C/N content are strongly dependent on the pyrolysis temperature. The as-obtained MNC-supported NiPt nanoparticles (NPs) were used as efficient catalysts toward complete dehydrogenation of hydrazine borane (HB) in alkaline solution at room temperature. Among all the catalysts investigated, the Ni60Pt40/MNC-800 nanocomposites (NCs) show the highest catalytic activity and 100% hydrogen selectivity. The total turnover frequency (TOF) of Ni60Pt40/MNC-800 NCs reached 1111 h−1 at room temperature, the highest activity among all catalysts reported to date. The superior catalytic properties were possibly a result of the electronic interaction between Ni and Pt, the synergistic effects of the NiPt NPs and MNC support, the ordered pore structure for free mass transfer and the small-sized metal NPs.

Hydrazine borane (N2H4BH3, 15.4 wt%) and hydrous hydrazine (N2H4·H2O, 8 wt%) are promising chemical hydrogen storage materials that have attracted much attention in recent years due to their high gravimetric hydrogen capacities. The selective and rapid catalytic dehydrogenation of N2H4BH3 and N2H4·H2O is the key to the potential use of the abovementioned materials in hydrogen applications. In this study, a series of Rh-MoOx nanoparticles (NPs) with various metal compositions have been successfully prepared via a simple one-step chemical reduction approach in the absence of a surfactant/support at room temperature. The obtained surfactant/support-free Rh-MoOx NPs exhibit good dispersibility and small particle size. Among all of the as-prepared Rh-MoOx NPs, the optimized Rh-MoOx catalysts with a molar ratio of 1:1 show the highest catalytic properties with 100% H2 selectivity for hydrogen evolution from aqueous N2H4BH3 and N2H4·H2O solutions at 323 K under alkaline conditions. The turnover frequency (TOF) values of Rh0.5(MoOx)0.5 NPs are 2000 and 750 h−1 for hydrogen evolution from N2H4BH3 and N2H4·H2O, respectively, which are among the highest values ever reported for Rh-based catalysts. The superior catalytic performances could be attributed to the small particles size, low crystallinity, modified electronic structure, and strong basic sites of Rh NPs induced by the MoOx dopant. The highly rapid and selective Rh-MoOx catalyst may further encourage the deployment and application of N2H4BH3 and N2H4·H2O as safe and convenient sources of hydrogen for fuel cells.

The original version of this article unfortunately contained a mistakes in Fig. 2B and Fig. 4A.

In recent years, the speed of urban development is faster and faster. With the acceleration of urbanization, the nature of land use and planning layout of urban planning area have changed dramatically. This leads to a rapid increase in the amount of urban construction information, and the efficiency of information processing and transmission. Urban planning approval is the core content of urban planning management, which directly affects urban construction and land development mode. The contents of road network analysis, demolition analysis and sunshine analysis in the urban planning system can not be fully displayed in the traditional two-dimensional GIS, so the system can not provi de a reliable basis for planning decision-makers. This paper presents a three-dimensional spatial analysis system for urban planning, which inherits the characteristics of three-dimensional GIS. At the same time, the system can analyze 3D data effectively. The system makes a full study of the more important aspects of urban planning, such as space measurement, demolition management, sunshine analysis, road network planning analysis, etc., and can analyze and audit the planning results.

Recently, the utilization of hydrazine borane (N2H4BH3) and hydrous hydrazine (N2H4·H2O) as promising hydrogen carriers has received increasing research interest. In this work, NiIr alloy nanoparticles (NPs) immobilized on lanthanum oxy-carbonate (NiIr/La2O2CO3) have been successfully synthesized through a sodium–hydroxide-assisted reduction approach at room temperature. It was found that ultrafine NiIr NPs with an average size of around 2.3 nm were effectively and highly dispersed on La2O2CO3. NiIr/La2O2CO3 nanocomposites (NCs) prepared with the assistance of NaOH showed much higher catalytic activity and H2 selectivity toward the N2H4BH3 dehydrogenation reaction as compared to those of NiIr/La2O2CO3–N prepared without addition of NaOH. Among all of the tested samples, the optimized Ni0.75Ir0.25/La2O2CO3 NCs exhibited the highest catalytic performance with 100% hydrogen selectivity for hydrogen generation from an aqueous solution of N2H4BH3. The total turnover frequency (TOF) of Ni0.75Ir0.25/La2O2CO3 NCs for this dehydrogenation reaction was found to be 1250 h−1 at 323 K, which is among the highest values ever reported. Additionally, this catalyst also exhibited a remarkable catalytic performance for efficient and complete decomposition of N2H4·H2O. This excellent catalytic performance could be attributed to the high dispersion of metal NPs and the strong interaction between the metal and support as well as the promotion effect of NaOH.

Hydrogen has been considered as an important alternative energy source for both environmental and economic reasons. The development of highly efficient and selective catalysts for hydrogen evolution from chemical hydrogen storage materials (e.g. hydrous hydrazine, N2H4·H2O) has become one of the most active research areas. In this study, MoOx-doped NiPt nanoparticles (NPs) have been successfully prepared via a simple one-step co-reduction strategy at room temperature. The characterization results show that the surfactant/support-free NiPt–MoOx NPs with a mean particle size of 5.0 nm are well-dispersed and in a low-crystalline/amorphous state. It is found that the prepared NiPt–MoOx samples show much higher catalytic activity toward the decomposition of N2H4 as compared to that of NiPt without the introduction of MoOx. In addition, among all the NiPt–MoOx NPs, the optimized Ni0.6Pt0.4–MoOx nanocatalyst shows 100% H2 selectivity and the best catalytic performance for the decomposition of N2H4 under alkaline conditions at 323 K. The TOF value of Ni0.6Pt0.4–MoOx NPs is found to be 822 h−1, which is among the highest values ever report for the same reaction. The excellent catalytic activities could be attributed to the modified electronic structure and the small particle size of NiPt NPs induced by the MoOx dopant. Other MoOx-doped Ni-based (NiM, M = Rh, Ir, Au, Ag and Ru) bimetallic catalysts also showed excellent catalytic activity. The present highly efficient and selective catalyst system may encourage the practical application of N2H4·H2O as a potential chemical hydrogen storage material.

The fatality rate of ovarian cancer ranks first among gynecological tumors, and the prognosis is poor. Diosmetin (Dio), a natural flavonoid obtained from citrus fruits, has been shown to have anti-tumor effects in lung, liver, and skin cancers. We aimed to investigate the effects of Dio on ovarian cancer A2780 and SKOV3 cells along with the underlying mechanisms. Our data showed that Dio inhibited the proliferation, migration, and invasion of these cells and induced their apoptosis. Moreover, Dio upregulated the levels of Bax and cleaved Caspase-3 and PARP while downregulating the level of Bcl2. Mechanistically, our results revealed that Dio inhibited Nrf2 and induced the production of reactive oxygen species (ROS). The ROS scavenger N-acetyl-L-cysteine (NAC) suppressed the inhibitory effect of Dio on the proliferation of the ovarian cancer cells. Additionally, overexpression of Nrf2 partially suppressed the Dio-induced apoptosis and proliferation inhibition in these cells. These findings indicate that Dio exerts an anti-tumor activity by upregulating ROS levels and inhibiting Nrf2, indicating that Dio is a promising chemotherapeutic candidate for the treatment of ovarian cancer.

Hydrogen is a potentially ideal alternative energy source for both environmental and economic reasons. The development of sustainable, efficient, and economical catalysts towards hydrogen generation from hydrogen storage materials (e.g., ammonia borane, AB) has been one of the active and challenging research areas. In this work, noble-metal-free CuCoMo nanoparticles (NPs) without any surfactant or support have been prepared via a facile co-reduction method at room temperature and used as highly efficient catalysts for hydrogen generation from an aqueous AB solution. Compared to their monometallic and bimetallic counterparts, the obtained trimetallic Cu0.72Co0.18Mo0.1 NPs exhibit the highest catalytic activity for the hydrolysis of AB with a total turnover frequency (TOF) value of 46.0 min−1 at room temperature under ambient atmosphere. The Cu0.72Co0.18Mo0.1 NPs only needed 0.63 min to completely hydrolyse AB in the presence of a basic solution (NaOH, 1 M) with a TOF value as high as 119.0 min−1 at room temperature, which is among the highest values of all the noble-metal-free catalysts ever reported for the same reaction, wherein NaOH plays an important role in improving the catalytic activity. In addition, it is found that the hydrogen generation rate can be improved by adding a base (e.g., NaOH, KOH, etc.) into the reaction solution, while the presence of NH4+ species (e.g., NH3·H2O, NH4Cl, etc.) is unfavorable for the hydrolysis of AB.

A transmission reflection selective ultranarrow-band metamaterial filter based on electromagnetically induced transparency (EIT) operating at visible wavelengths is demonstrated theoretically and experimentally. The theoretical work starts with the design of an EIT structure with two separate resonance parts. Then the two resonance parts are connected and the hardness of the metamaterial filter is further increased by adding a glass substrate. Numerical simulation results show that the metamaterial filter not only exhibits ultranarrow-band transmission reflection selective spectra, but also exhibits wavelength tunable spectra for both transmission and reflection. To verify the simulation results, a filter sample is fabricated and the spectral responses are measured.

A nonpolarizing narrow band metamaterial transmission filter based on EIT operating at visible wavelengths is demonstrated theoretically and experimentally. The two separated resonance components that are able to generate EIT effect are connected using a SiO2 film layer and the hardness of the metamaterial filter is further improved by adding a glass substrate. The theoretical results are calculated by using the finite-difference time-domain simulation method and a metamaterial filter sample is fabricated and measured to verify the simulation spectrum. The full width at half-maximums of simulation and measured spectra are 0.74 nm and 1.61 nm respectively. Electric field distributions are also calculated to illustrate the physical mechanism. The novel method might be helpful to improve the processability of the narrow band metamaterial transmission filter, and also to further promote the applications of this kind of metamaterial filter.

As one of the main forms of urbanization in my country, urban construction is the process of building original natural or semi-natural ecosystems into urban artificial ecosystems from the perspective of ecology. It is the construction and replacement of ecosystem types and the process of encroachment. Urban planning must pay particular attention to the forward-looking nature of its ecological planning. While truly enhancing the city’s overall ecosystem service capabilities, it also prevents new ecological and environmental problems from being induced. Through theoretical analysis of the characteristics of ecosystem changes in the process of urban construction, combined with typical cases, several key issues in urban ecological planning have been summarized and condensed, and corresponding planning strategies and techniques have been proposed, with a view to providing ecological solutions for large-scale urban development in my country. Provide theoretical support for environmental protection work.

The paper selects a garden as a typical object to study urban garden plants, and uses methods such as video statistics, digital camera record analysis, manual counting, and questionnaire survey statistics (CTVM) to analyse the laws of garden plants in different time periods Based on the analysis and research, a mathematical model was established to explain the temporal and spatial behaviour of garden plants, so as to evaluate the landscape planning of urban gardens and provide a basis for studying the landscape planning of urban gardens. At the same time, the paper designs a web-based urban garden plant protection management system to improve the level of intelligent management of urban gardens.

High-risk Human papillomaviruses (HPVs) types are associated with more than 90% of premalignant and malignant squamous lesions of the uterine cervix. The E6 oncoprotein of high-risk HPVs is a key determinant in cell transformation because it induces the degradation of the host pro-apoptotic tumor suppressor p53. E6 recruits the intracellular ubiquitin ligase E6AP and subsequently induces proteasome-dependent p53 degradation. Neither E6 nor E6AP alone interact with p53; however, the precise mechanism of the functional regulation of the E6/E6AP/p53 complex is unclear. Here, we showed that the high-risk HPV E6 proteins are ubiquitinated during E6/E6AP/p53 complex assembly and degraded by the proteasome system. Increasing p53 expression enhanced E6/E6AP/p53 assembly and facilitated E6 ubiquitination and degradation. The dominant negative mutant of p53 R175H, which does not efficiently bind E6, decreased E6 ubiquitination and increased stability. Furthermore, we showed that the ubiquitin ligase E6AP is essential for E6 ubiquitination, and downregulation of E6AP expression increased E6 stability. We also showed that p53 R175H inhibited E6-mediated p53 degradation. Consistently, the host deubiquitinating enzyme USP15 removed ubiquitin chains from E6 proteins and inhibited E6-mediated p53 degradation. Crucially, ectopic expression of either p53 R175H or USP15 promoted p53-triggered apoptosis in human cervical cancer cells. Considering the importance of ubiquitinated E6 on p53 degradation, the disruption of E6 ubiquitination represents an attractive pharmacological intervention against HPV-positive human cervical cancer. Importance Virtually 100% of cervical cancers are linked to HPV infection. Commercial HPV vaccines are estimated to prevent up to 90% of HPV-associated cancers, while they do not eliminate persistent HPV infections and have no effect on the progression to malignancy. Hence, the development of novel therapeutic interventions against HPV is urgently required. The HPV oncoprotein E6 binds to the intracellular E3 ubiquitin ligase E6AP and p53 resulting in the degradation of p53. In this study, we demonstrate that HPV E6 is ubiquitinated by E6AP in presence of p53. Crucially, ubiquitination of E6 is important for p53 degradation and blockage of E6 ubiquitination negatively interferes with E6-mediated p53 degradation and enhances the apoptotic effects of p53 and the cytotoxicity of DNA damage in HPV-positive cervical cancer cells. Importantly, our data suggest that the HPV oncogene E6 might be an optimal pharmacologic.

Surgery and chemotherapy are the gold-standard treatments for ovarian cancer. The major cause of treatment failure in patients with ovarian cancer is tumoral heterogeneity and drug resistance. Paclitaxel (PTX) is one of the most commonly used first-line drugs for ovarian cancer chemotherapy. Unfortunately, the mechanisms of PTX chemoresistance remain unclear. Here, we examined the effects of post-translational neddylation on the sensitivity of ovarian cancer cells (OCCs) to PTX-induced apoptosis. Disruption of protein neddylation with the first-in-class inhibitor MLN4924 dramatically neutralized PTX-mediated antiproliferative, antimigration, and apoptotic effects in human OCCs. Moreover, MLN4924 treatment interrupted PTX-induced microtubule polymerization. Importantly, two neddylation conjugating E2 enzymes, UBE2M and UBE2F, were found to play essential roles in PTX-induced cytotoxicity and tubulin polymerization in OCCs. In summary, our findings demonstrated that disruption of protein neddylation by MLN4924 conferred resistance to PTX and provided insights into the potential mechanisms of PTX chemoresistance in ovarian cancer.

As an ideal hydrogen supplier in liquid phase, hydrous hydrazine has gained a lot of attention for safe and efficient storage as well as transportation of hydrogen. Herein, a low Pt-containing Ni–Pt bimetallic catalyst immobilized on novel MIL-101/rGO composite has been prepared by a facile impregnation-reduction approach. Unexpectedly, the resultant Ni0.9Pt0.1/MIL-101/rGO catalyst exhibits optimal catalytic performance and 100% H2 selectivity for hydrogen evolution from hydrous hydrazine under alkaline conditions at 323 K, giving a turnover frequency (TOF) value of 960.0 h−1, which is a relatively higher value ever reported heterogeneous catalysts. Even at room temperature, Ni0.9Pt0.1/MIL-101/rGO catalyst shows excellent catalytic activity for dehydrogenation of hydrazine as well as hydrazine borane. In addition, the Ni0.9Pt0.1/MIL-101/rGO catalyst also exhibits excellent durability. Even after eight recycles, the catalytic activity is no significant decrease, and the H2 selectivity still remains 100%.