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The first enantioselective total synthesis of aryltetralin lignan acetals, (-)-formosanol, (+)-tsugacetal, (+)-methyl β-conidendral, and their enantiomers have been accomplished on the basis of the Pd-catalyzed asymmetric allylic cycloaddition as a key step. Six stereoisomers of the lignan acetals have been synthesized via a 7-8 step sequence in up to 14% overall yield. The

An efficient method for the synthesis of functionalized chiral tetrahydrofuran (THF) acetals via Pd-catalyzed asymmetric allylic cycloaddition has been developed. With a palladium catalyst coordinated by a chiral phosphine ligand, the protocol is enabled to combine readily available vinyl epoxides and β-keto enol ethers to produce THF acetals bearing three stereocenters in a broad substrate scope with uniformly high levels of enantio- and diastereoselectivity.

The first Pd-catalyzed asymmetric three-component reaction of 2,3-allenol, aryl iodides, and 2-arylmethylenemolononitriles has been developed via an allenol carbopalladation and an allylic cycloaddition cascade. This process allows rapid access to substituted tetrahydrofurans bearing diverse functional groups in good yields with high diastereoselectivities and excellent enantioselectivities. The concise total synthesis of a lignan, (-)-2-episesaminone, has been achieved by the elaboration of a functionalized tetrahydrofuran obtained from this reaction.

Pd-Catalyzed allylic substitution of vinylethylene carbonates with 1,2,4-triazoles has been developed to produce N1-allylated 1,2,4-triazoles in high yields with excellent regio- and stereoselectivities.

Diabetes is a disease that seriously endangers human health. Early detection and early treatment can reduce the likelihood of complications and mortality. The predictive model can effectively solve the above problems and provide helpful information for the clinic. Based on this, it is proposed to apply the idea of integrated algorithm in DBN algorithm, collect the hospital data by investigating its related factors, clean and process the collected data, and sample and model the processed data multiple times. It is shown that a single DBN classifier is better than support vector machine and logistic regression algorithm. The model established by the integrated deep confidence network has a significant improvement in classification accuracy compared to a single DBN classifier, and solves the unstable classification effect of a single DBN classifier.

A new asymmetric catalytic protocol for the synthesis of enantioenriched N-allyl 2-pyrodones has been developed via the first Pd-catalyzed regio- and enantioselective aminoarylation of allenols wit...

Pd-catalyzed regio- and enantioselective allylic etherification of vinylethylene carbonates (VECs) with diols has been developed. By using cooperative catalysts of the chiral palladium complex and triethylborane in mild conditions, the process gave monoetherified and bisetherified polyglycol derivatives with tetrasubstituted stereocenters in high yields with complete regioselectivities and high levels of enantio- and diastereoselectivities.

A useful method for the enantioselective preparation of isoxazoline N-oxides via Pd-catalyzed asymmetric allylic cycloaddition of nitro-containing allylic carbonates has been developed. By using pa...

OBJECTIVE The purpose of this study was to assess the fibrinolytic status after cardiopulmonary bypass in rheumatic valvular heart disease patients, and detect the associated factors of post-cardiopulmonary bypass hyperfibrinolysis. METHODS According to the fibrinolytic status after cardiopulmonary bypass, 203 rheumatic valvular heart disease patients were divided into two groups: hyperfibrinolysis group (H group, n = 78) and non-hyperfibrinolysis group (NH group, n = 125). The demographic characteristics, operative variables, and postoperative follow-ups were compared between these two groups. RESULTS The incidence of hyperfibrinolysis was 38.4% after cardiopulmonary bypass. Patients in the H group had a significant higher incidence of preoperative atrial fibrillation than patients in the NH group (92.3% vs. 55.2%, P

Background Gastric cancer is one of the most common and deadly malignancies worldwide. Despite recent medical progress, the 5-year survival rate of gastric cancer is still unsatisfactory. 5-fluorouracil (5-Fu) is one of the first-line antineoplastic treatments for gastric cancer, as it can effectively induce cancer cell apoptosis. However, the effect of 5-Fu is limited due to drug resistance of the malignant tumor. Previous studies have reported that Sotetsuflavone from Cycas revoluta Thunb. can markedly suppress lung cancer cell proliferation by apoptosis, though its effect on gastric cancer remains unknown. Aim To investigate the inhibitory effect of Cycas revoluta Thunb. and to determine whether it can overcome gastric cancer cell drug resistance to 5-Fu. Methods Cell viability was examined to determine whether the natural extract of Cycas revoluta Thunb. induced gastric cancer cell death. The half-maximal effective concentration and the half-maximal lethal concentration were calculatede. Wound-healing and transwell assays were performed to examine gastric cancer cell motility. Clonogenic assays were performed to investigate the synergistic effects of Cycas revoluta Thunb. with 5-Fu, and apoptotic bodies were detected by Hoechst staining. Western blotting was performed to examine the expression of related proteins and to investigate the molecular mechanism of Cycas revoluta Thunb.-induced cancer cell apoptosis. The expressions of proteins, including mammalian target of rapamycin (mTOR) and p-AKT, were detected in different combinations of treatments for 48 h, then analyzed by ECL detection. Results Gastric cancer cells were more sensitive to the natural extract of Cycas revoluta Thunb. compared to normal gastric epithelial cells, and the extract effectively inhibited gastric cancer cell migration and invasion. The extract improved the anti-cancer effect of 5-Fu by enhancing the chemosensitization of gastric cancer cells. Extract plus 5-Fu further reduced the expression of the drug-resistance-related proteins p-AKT and mTOR after 48 h compared to 5-Fu alone. Compared to 5-Fu treatment alone, mTOR and p-AKT expression was significantly reduced by about 50% and 75%, respectively. We also found that the natural extract of Cycas revoluta Thunb. further increased 5-Fu-induced gastric cancer cell apoptosis. Expression of apoptosis-related protein X-linked inhibitor of apoptosis protein and apoptosis inducing factor were significantly reduced and increased, respectively, in the 5-Fu-resistant gastric cancer line SGC-7901/R treated with extract plus 5-Fu, while the expression of survivin did not change. Conclusion The natural extract of Cycas revoluta Thunb. effectively inhibited gastric cancer cell growth and enhanced the anti-cancer effect of 5-Fu through the AKT-mTOR pathway.

A series of more than 20 multisubstituted pyrrolidine-2-carboxylates were synthesized via a one-pot cycloaddition of an araldehyde, an amino acid ester, and a chalcone catalyzed by I2/K2CO3 in tetrahydrofuran at 80 °C. The advantages of this method are readily available starting materials, mild conditions, and simple operation, and it is metal free and yields are good to excellent.

Background Guizhi decoction (GZD), a classical Chinese herbal formula, has been widely used to treat hypertension, but its underlying mechanisms remain elusive. The present study aimed to explore its therapeutic effects and potential mechanisms in the treatment of hypertension using network pharmacology and experimental validation. Methods The active ingredients and corresponding targets were collected from Traditional Chinese Medicine Systems Pharmacology database and Analysis Platform (TCMSP). The targets related to hypertension were identified from multiple databases, and multiple networks were constructed to identify key compounds, hub targets, and main biological processes and pathways of GZD against hypertension. The Surflex-Dock software was used to validate the binding affinity between key targets and their corresponding active compounds. The Dahl salt-sensitive rat model was used to evaluate the therapeutic effects of GZD on hypertension. Results A total of 112 active ingredients, 222 targets of GZD and 341 hypertension- related targets were obtained. Furthermore, 56 overlapping targets were identified, five of which were determined as the hub targets to perform experimental verification, including interleukin 6 (IL-6), C-C motif chemokine 2 (CCL2), IL-1β, matrix metalloproteinase 2(MMP-2), and MMP9. Pathway enrichment

Herein, a practical and efficient approach to tetrahydrofurans with three-stereocenters has been developed through Pd-catalyzed asymmetric allylic cycloaddition of vinylethylene carbonates (VECs) with 2-nitroacrylates under mild conditions. By using this asymmetric catalytic reaction as a key step, several furofuran lignans with stereodivergency have been effectively synthesized through 5- or 6-step sequences from readily available starting materials.

An efficient method for the construction of arylated allylic ethers was developed via three-component tandem arylation and allylic etherification of 2,3-allenol with aryl iodides and alcohols. In the cooperative catalytic system of a palladium complex and triethylborane, the process allows rapid access to functionalized 1-arylvinylated 1,2-diol derivatives in good to high yields with complete branch-selectivities. The synthetic utility of the present process was demonstrated by the late-stage functionalization of a drug molecule, the gram-scale synthesis and the elaboration of the products.

An efficient method for the enantio- and diastereoselective construction of multisubstituted tetrahydrofurans via asymmetric decarboxylative cycloaddition of vinylethylene carbonates with β-nitroolefins under a cooperative catalysis of palladium complex and squaramide is developed. By using a palladium complex generated in situ from Pd2(dba)3·CHCl3 and phosphoramidite L1 and chiral squaramide OC4 as cooperative catalysts under mild conditions, the process provided multisubstituted tetrahydrofurans bearing a quaternary stereocenter in good to high yields with acceptably high enantio- and diastereoselectivities.

Synergistic effects of synthetic phosphonium sulfonates (PhSs) bearing different groups with expandable graphite (EG) on flame retardancy properties in poly(ethylene-co-vinyl acetate) (EVA) rubber blends have been studied by limiting oxygen index (LOI), UL-94 test, cone calorimeter test (CCT), and thermogravimetric analysis (TGA). The EVA/EG/PhS composites revealed excellent flame retardancies. Upon adding 2.5 wt% of PhSs and 20 wt% of EG to EVA matrix, V-0 rating can be achieved. The heat release rate (HRR) and the total heat release (THR) of EVA/PhS-2(2.5 wt%)/EG(20 wt%) and EVA/PhS-4(2.5 wt%)/EG(20 wt%) blends decreased remarkably based on CCT. In addition, the thermal stabilities and mechanical properties of EVA/EG/PhS composites did not deteriorate comparing with those of EVA/EG composites.

An efficient method for the construction of furanobenzodihydropyran skeletons has been developed through Pd-catalyzed asymmetric decarboxylative cycloaddition of vinylethylene carbonates with 3-cyanochromones. By using a palladium complex generated in situ from [Pd2(dba)3]·CHCl3 and phosphoramidite L3 as a catalyst under mild reaction conditions, the process afforded furanobenzodihydropyrans bearing vicinal quaternary stereocenters in high yields with good to high enantio- and diastereoselectivities.

Hypoxia is an important risk factor for pulmonary arterial remodeling in pulmonary arterial hypertension (PAH). Vascular remodeling in hypoxia-induced PAH is driven by excessive proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs). The purpose of the present study was to explore the expression of CTRP9 in rats model of hypoxia-induced PAH and investigate the effects of CTRP9 on HPASMCs function in vitro and determine the underlying mechanisms. We established a rat model of hypoxic PAH, which showed a downregulation of CTRP9 expression. In HPASMCs cultured under the condition of hypoxia, treatment with CTRP9 notably restrained cell proliferation responses to hypoxia accompanied with decreased two biomarkers of cell proliferation Ki-67 and PCNA. Meanwhile, CTRP9 strikingly promoted hypoxia-mediated cell apoptosis as reflected by upregulation of Bax and downregulation of Bcl-2, as well as enhanced Caspase 3 activity. Additionally, CTRP9 treatment dramatically prevented the migratory potential by declined the expression of MMP-2 and MMP-9. Moreover treatment with CTRP9 augmented hypoxia-mediated differentiation by elevating the expression level of differentiation markers α-SMA and SM22. Mechanistically, anti-proliferative effects conferred by CTRP9 are mediated through suppression of TGF-β1/ERK1/2 pathway. Collectively, we identified CTRP9 as a novel mediator of PASMC growth in hypoxia-mediated PAH, indicating that CTRP9 in the pulmonary vasculature may be an underlying mechanism in the development of hypoxia-induced PAH. Our study, for the first time, established that CTRP9 plays a protective role of CTRP9 in pulmonary vascular remodeling, pointing to its potential clinical value for patients with PAH.

Ultrasound promoted enantioselelctive decarboxylative protonation reaction of α-aminomalonate hemiesters 1 in the presence of chiral cinchona-derived squaramide Bronsted bases under mild conditions afforded both the (S) and (R) enantiomers of α-amino acid derivatives 2 in excellent yields (>90%) and excellent enantioselectivities (up to 98% ee).

MATPOWER is one of wide used authoriterative open source software of power flow calculation in the world. However, it only provides a model of the two-winding transformer thus limiting its application in power system with a three-winding transformer which is very popular in the power system. This paper proposes a method to convert three -winding transformer into a model with two-winding transformer structure. The effectiveness of treatment method has been proved through a case study of the power system.

An efficient method for the enantioselective synthesis of cyclic ureas has been developed through Pd-catalyzed asymmetric allylic cycloaddition of readily accessible nitrogen-containing allylic carbonates with isocyanates. By using a palladium complex in situ generated from Pd

A useful method for the enantioselective preparation of isoxazoline

An efficient method for the asymmetric synthesis of N-substituted 2-pyridones via Pd-catalyzed regio- and enantioselective allylic substitution of hydroxyl-containing allylic carbonates with 2-pyridones has been developed. By using a palladium complex in situ generated from Pd2(dba)3·CHCl3 and phosphoramidite L2 as a ligand, the process allowed rapid access to N-substituted 2-pyridones with complete chemo- and regioselectivities and good to high enantioselectivities.

Iodine-promoted direct diamination of α,β-unsaturated ketone to form two C-N bonds has been developed starting from chalcone and secondary amine. This reaction was performed in THF at 50 °C in the presence of I2 and K2 CO3. The protocol is metal-free, operationally simple and carried out under mild conditions, providing an effective new way for directing diamination reactions.

Gastric cancer is one of the most common and deadly malignancies worldwide. Despite recent medical progress, the 5-year survival rate of gastric cancer is still unsatisfactory. 5-fluorouracil (5-Fu) is one of the first-line antineoplastic treatments for gastric cancer, as it can effectively induce cancer cell apoptosis. However, the effect of 5-Fu is limited due to drug resistance of the malignant tumor. Previous studies have reported that Sotetsuflavone fromTo investigate the inhibitory effect ofCell viability was examined to determine whether the natural extract ofGastric cancer cells were more sensitive to the natural extract ofThe natural extract of

Phosphonium sulfonates (PhSs) as flame retardants have been synthesized from organic sulfonates and triphenylphosphine as starting materials. The PhSs revealed good thermal stability and efficient flame retardancy for polycarbonate (PC). The LOI values increased with the increase of PhS-1 contents to PC and reached 33.7 when the PhS-1 content is 10 phr, and the V-0 rating can be achieved when only 5 phr PhSs are added. The cone calorimeter analysis indicated that the HRR and THR were reduced with the addition of PhSs to the PC matrix. The PhS bearing alkene group revealed highest LOI values and lowest peak HRR (pHRR) values for PC. The morphology of the residual chars after LOI test and the element content of the chars after CONE test were also investigated by SEM and EDX.

A practical and greener method of the cross-coupling of vinylethylene carbonates (VECs) with arylboronic acids has been described. The coupling reaction was catalyzed by in situ generated palladium nanoparticles (PdNPs) without any ligands and additional stabilizers in water under ambient conditions to provide useful 4-hydroxylprenylarenes and their derivatives in good to high yields.

The pursuit of highly efficient phosphorous flame retardants for polymer-matrix composites is of great sense in industrial and academic community. In the contribution, a phosphorous-phosphorous (P-P) synergy between structurally well-defined phosphonium sulfonates (PhS) and triphenyl phosphate (TPP) or bisphenol A bis (diphenyl phosphate) (BDP) was specifically revealed in PC/ABS alloy. Compared with TPP and BDP loadings of respective 14 wt% and 12 wt% to pass UL-94 V-0, the mere 8 wt% FRs was required via an exceptional synergy of 2% allyl-substituted PhS and 6 wt% TPP (or BDP). In parallel, the studied P-P synergy reduced heat release rate and total heat release significantly. Deep mechanism analysis by solid NMR and Py/GC-MS unveiled a concurrent optimization of condensed-phase and vapor-phase effect. Additionally, the multifunctional reinforcement of tensile property, thermal resistance and hydrolytic resistance was sysmatically investigated. In perspective, the P-P synergy between structurally tailored PhSs and phosphates exploits a pathway for highly efficiently fire-safe polymers.

An efficient and practical approach to phosphonium salts has been developed. By the reaction of phosphines and different acid sources with orthoformates in one-step operation, the process allowed rapid access to phosphonium salts with diverse counterions in high yield after the purification by recrystallization. The flame retardant performance in PC has also been examined by blending several phosphonium salts to PC respectively. Phosphonium phosphates showed excellent flame retardancy in PC with only 2 phr blending.

Communities are virtually ubiquitous in real-world networks, and the statistic of modularity index Q is the classical measurement for community detection algorithms. However, the relationship between the modularity property and network multilever micro-scale structures is still not clear. In this paper, we study community detection results both in artificial and real-life complex networks by constructing different order null networks, and the results uncover that how micro-structures (such as degree distribution, assortativity and clustering coefficient) affect community properties. Meanwhile, we also propose two novel null networks (increasing or decreasing community structures) to verify the robustness of different community detection algorithms. Our results indicate that the modularity index Q is not a suitable statistic to measure the weak community property which is widely available in empirical networks. Our findings can not only be used to test the robustness of different community detection methods, but also be helpful to uncover the correlation of network structures between microcosmic and mesoscopic scales.

The overwhelming amount of knowledge discovered form product data necessitates mechanisms for efficient information filtering during complex product design. In order to overcome the incompatibility of the traditional collaborative filtering algorithm in product design knowledge recommendation, A process-centric design knowledge management model is given, in which knowledge is reasonably classified and effectively organized. A task based knowledge recommendation algorithm considering task similarity and time factor is given. Application of the model and algorithm on construction machinery engine design support system is introduced and discussed.

BACKGROUND MicroRNA (miR) has been proved to be an important biomarker for tumors because it can regulate occurrence, progression, invasion, and metastasis of cancer. A previous study has shown the involvement of miR-503 in multiple gastrointestinal tumors. Its detailed role and immune regulatory function in esophagus carcinoma, however, remains unknown. This study thus investigated the effect of miR-503 in regulating growth, proliferation, and invasion of esophagus cancer and its influence on cytokine secretion. MATERIAL AND METHODS Esophagus carcinoma cell line EC9706 and normal esophageal epithelial cell line HEEC were transfected with miR-503 inhibitor. MTT assay was used to quantify the cell proliferation, and a Transwell chamber was used to evaluate cell invasion. Release of cytokines, including interleukin-2 (IL-2), IL-4, IL-10, and interferon-γ (IFN-γ), was measured by enzyme-linked immunosorbent assay (ELISA). RESULTS MiR-503 expression was significantly elevated in esophagus carcinoma cells (p

N-[4-(4,6-Dimethyl-2-pyrimidinyloxy)-3-methylphenyl]-N'-[2-(dimethylamino)]benzoylurea (SUD) is a novel synthesized benzoylurea derivative. We selected several human cancer cell lines to investigate whether SUD can inhibit the growth of cancer cells. We selected the liver cell line L-02 to investigate the effect of SUD on the normal cells. Flow cytometric analysis was used to detect the effect of SUD on cell cycle, Hoechst 33258 staining was used to evaluate the apoptosis induced by SUD, real-time fluorescence quantitative PCR was used to investigate the expression of the cell cycle-relevant and apoptosis-relevant genes, a reactive oxygen species (ROS) assay was used to observe the production of ROS, and western blotting was used to determine the level of cell cycle-relevant and apoptosis-relevant proteins. According to the results of the MTT assay, the growth of human cancer cell lines was significantly inhibited by SUD treatment in a time-dependent and concentration-dependent manner; however, the growth of human normal cells was not significantly inhibited by SUD treatment. The results of flow cytometric analyses showed that SUD induced cell-cycle arrest at the G2-phase in MCF-7 cells and at the G1-phase in BGC-823 cells. The results of Hoechst 33258 staining showed that SUD induced apoptosis in MCF-7 and BGC-823 cells. The results of the ROS assay showed that the production of ROS was increased by SUD in MCF-7 and BGC-823 cells. Our research suggests that the growth-inhibitory effect of SUD on MCF-7 cells was related to G2-phase arrest, which was associated with the upregulated expression of p53 and Chk1 proteins, and downregulation of the cyclin B1 gene, cdc25a, and cyclin-dependent kinase 1 (CDK1) proteins; the growth-inhibitory effect of SUD on BGC-823 cells was related to G1-phase arrest, which was associated with upregulation of the p53 gene and Chk1 protein and downregulation of cdc25a protein and the CDK4 gene. SUD also induced apoptosis in MCF-7 and BGC-823 cell lines through the mitochondrial pathway in a p53-dependent manner.

Due to the lack of condition monitoring and health analysis of the equipment in the daily operations, serious accident happened and it caused the incorrect results of fault diagnosis. We propose a method of condition monitoring and fault prediction based on extension theory. The method established a matter element mode to give the formal description of the state of the equipment. It used dependent function to do the qualitative and quantitative analysis of the equipment state. Through the method, we can change the model of maintenance which is always done after fault occurred. We use the method on the example of turbines to prove the feasibility and effectiveness of the method.

A practical and greener process for the allyl–aryl coupling of allylic carbonates with arylboronic acids catalyzed by in situ generated palladium nanoparticles (PdNPs) in ionic liquid (IL) has been described. The PdNPs showed high catalytic activity for the coupling reaction in the IL to afford allyl–aryl coupling products in good to high yields with complete regio- and E/Z selectivities. The PdNPs were readily immobilized in the IL phase and the catalyst can be reused several times without significant loss of catalytic activity and stereospecificity.