查找使用阿拉丁产品的科研文献

BMP-2 and VEGF-A modRNAs in collagen scaffold synergistically drive bone repair through osteogenic and angiogenic pathways

Geng Yingnan,Duan Huichuan,Xu Liang,Witman Nevin,Yan Bingqian,Yu Zheyuan,Wang Huijing,Tan Yao,Lin Liqin,Li Dong,Bai Shanshan,Fritsche-Danielson Regina,Yuan Jie,Chien Kenneth,Wei Min,Fu Wei

Bone has a remarkable potential for self-healing and repair, yet several injury types are non-healing even after surgical or non-surgical treatment. Regenerative therapies that induce bone repair or improve the rate of recovery are being intensely investigated. Here, we probed the potential of bone marrow stem cells (BMSCs) engineered with chemically modified mRNAs (modRNA) encoding the hBMP-2 and VEGF-A gene to therapeutically heal bone. Induction of osteogenesis from modRNA-treated BMSCs was confirmed by expression profiles of osteogenic related markers and the presence of mineralization deposits. To test for therapeutic efficacy, a collagen scaffold inoculated with modRNA-treated BMSCs was explored in an in vivo skull defect model. We show that hBMP-2 and VEGF-A modRNAs synergistically drive osteogenic and angiogenic programs resulting in superior healing properties. This study exploits chemically modified mRNAs, together with biomaterials, as a potential approach for the clinical treatment of bone injury and defects.

Unraveling the reaction route and kinetics of 3-methyl-3-penten-2-one synthesis for synthetic ketone fragrances

Ling Li,Peng Hong,Anton A Kiss,Hui Tian,Xiaoda Wang,Ting Qiu

BACKGROUND 3-Methyl-3-penten-2-one (3M3P) is an indispensable raw material used for the synthesis of OTNE (octahydrotetramethyl acetophenone), a synthetic ketone fragrance known by commercial trade names, such as Iso E Super® , which is one of the most important ingredients in perfumes. This work is the first to unravel the reaction route and kinetics for the synthesis of 3M3P via the cross-aldol condensation of acetaldehyde with butanone, catalyzed by the heterogeneous acidic ion exchange resin (NKC-9). RESULTS An effective method was developed to evaluate this complex reaction system: the reaction routes were determined experimentally from the product structures detected by Gas Chromatography Mass Spectrometry (GC-MS), and the significance of side reactions were evaluated by the Yoneda group contribution method. The major side reactions are the self-condensation of acetaldehyde (significant even under optimized reaction conditions) and the cross-aldol condensation of acetaldehyde with 3M3P (which could be effectively suppressed at high butanone-acetaldehyde molar ratio). The reaction kinetics was investigated at temperatures of 60–90 °C, catalyst mass fraction of 5 to 15%, and molar ratio of 5–20. At optimized reaction conditions, the yield of 3M3P was up to 90.85%, which is 2.4 times higher than that for the classic homogeneous catalysts (yield <38%). CONCLUSION Acidic ion exchange resin NKC-9 is a high-selective green catalyst for the cross-aldol condensation of acetaldehyde with butanone. Integrating experimental determination and thermomechanical analysis is an effective method to unravel the main reaction routes for a complex system. © 2020 Society of Chemical Industry (SCI)

Experimental and correlated liquid–liquid equilibrium data for (water + 1,6-hexanediol + 1-butanol or 2-methyl-1-propanol)

Xingchuan Yang,Xiangmeng Chen,Chunmei Cao,Li Xu,Guoji Liu

Solubility and liquid–liquid equilibria data for ternary systems for (water + 1,6-hexanediol + 1-butanol/2-methyl-1-propanol) were obtained at (293.15–323.15) K under atmospheric pressure. The LLE data were determined using a double-jacketed glass vessel, and the solubility curves were acquired by the cloud-point method. The distribution coefficient and separation factors were calculated and the reliability of experimental data was assessed by the Othmer–Tobias equation and Hand equation. The measured LLE data were fitted by NRTL and UNIQUAC models and binary parameters were obtained by using of Aspen Plus software. The calculated root-mean-square deviation values show that the calculated results from models showed good agreement with experimental data.

Interfacial electronic interaction of atomically dispersed IrClx on ultrathin Co(OH)2/CNTs for efficient electrocatalytic water oxidation

Yiwen Huang,Guijuan Wei,Jia He,Cuihua An,Min Hu,Miao Shu,Junfa Zhu,Shuang Yao,Wei Xi,Rui Si,Zhi-Ming Zhang,Changhua An

The exploration of highly-efficient oxygen evolution reaction (OER) electrocatalyst with well-defined structure to understand specific structure-performance relationship is crucial to meet the requirement of water-splitting. Herein, we firstly used atomically dispersed IrCl x to uniformly decorate ultrathin Co(OH) 2 nanosheets to dramatically improve electrocatalytic activity. The synthesized IrCl x -Co(OH) 2 nanosheets/carbon nanotubes (CNTs) exhibits an overpotential of 230 mV to reach 10 mA/cm 2 , which was much enhanced compared to that of pristine Co(OH) 2 /CNTs (308 mV) and commercial benchmark IrO 2 (309 mV). X-ray absorption fine structure and density functional theory simulations demonstrate strong interfacial interaction between IrCl x and Co(OH) 2 nanosheets via the Cl-Ir-O and Ir-Cl-Co bond can efficiently boost its electronic conductivity. The accelerated charge transfer promotes the formation of more positively charged O atoms around cobalt centers, which is beneficial for the deprotonation on IrCl x -Co(OH) 2 and makes the catalyst facilitate OER.

Dielectric strength of glass fibre fabric reinforced epoxy by nano-Al2O3

Shuang Wang,Yu Chen,Jiale Mao,Cong Liu,Lei Zhang,Yonghong Cheng,Chaoyun Du,Toshikatsu Tanaka

Synthesis of Generation-2 polyamidoamine based ionic liquid: Efficient dendrimer based catalytic green fuel production from yellow grease

Balaji Panchal,Kai Bian,Tao Chang,Zheng Zhu,Jinxi Wang,Shenjun Qin,Cunliang Zhao,Yuzhuang Sun

A new series of acidic, dendrimeric polyamidoamine based polymeric ionic liquids of [PAMAM 3256 C n ] were synthesized with a second generation polyamidoamine dendrimer , alkyl bromides and 1, 3-propane sultone via a two-step procedure. The structure of functional ionic liquids was characterized by Fourier-transform infrared spectroscopy, nuclear magnetic resonance spectroscopy. The polyamidoamine -1- dodecyl [PAMAM 3256 C 12 ] catalyst was used for green fuel production via the transesterification of yellow grease. The influence of reaction variables on the green fuel yield was studied using this catalyst. The catalyst was effective having achieved a 93% green fuel yield from yellow grease after 6 h of reaction at 65 °C, using 306.8 mol (10 mmol) (wt % based on molar concentration of lipids) of [PAMAM 3256 C 12 ] catalyst, a yellow grease-to-methanol molar ratio of 1:20 with a constant agitation speed 800 rpm. The catalyst was showed excellent stability for yellow grease transesterification over four cycles. Additionally, catalysts showed excellent transesterification activity of Jatropha curcas , Ricinus communis , and Pistacia chinensis oil, with green fuel yields of 90, 91, and 92%, respectively. The properties of green fuel were met the ASTM D6751-02 standards. Results indicate that the [PAMAM 3256 C 12 ] catalyst system shows promising potential as a viable industrial-scale alternative.

Ultrasensitive supersandwich-type electrochemical sensor for SARS-CoV-2 from the infected COVID-19 patients using a smartphone

Hui Zhao,Feng Liu,Wei Xie,Tai-Cheng Zhou,Jun OuYang,Lian Jin,Hui Li,Chun-Yan Zhao,Liang Zhang,Jia Wei,Ya-Ping Zhang,Can-Peng Li

The recent pandemic outbreak of COVID-19 caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses a threat to public health globally. Thus, developing a rapid, accurate, and easy-to-implement diagnostic system for SARS-CoV-2 is crucial for controlling infection sources and monitoring illness progression. Here, we reported an ultrasensitive electrochemical detection technology using calixarene functionalized graphene oxide for targeting RNA of SARS-CoV-2. Based on a supersandwich-type recognition strategy, the technology was confirmed to practicably detect the RNA of SARS-CoV-2 without nucleic acid amplification and reverse-transcription by using a portable electrochemical smartphone. The biosensor showed high specificity and selectivity during in silico analysis and actual testing. A total of 88 RNA extracts from 25 SARS-CoV-2-confirmed patients and eight recovery patients were detected using the biosensor. The detectable ratios (85.5 % and 46.2 %) were higher than those obtained using RT-qPCR (56.5 % and 7.7 %). The limit of detection (LOD) of the clinical specimen was 200 copies/mL, which is the lowest LOD among the published RNA measurement of SARS-CoV-2 to date. Additionally, only two copies (10 μL) of SARS-CoV-2 were required for per assay. Therefore, we developed an ultrasensitive, accurate, and convenient assay for SARS-CoV-2 detection, providing a potential method for point-of-care testing.

2-Bromoanthraquinone as a highly efficient photocatalyst for the oxidation of sec-aromatic alcohols: experimental and DFT study

Shengfu Liao,Jianguo Liu,Long Yan,Qiying Liu,Guanghui Chen,Longlong Ma

Anthraquinones are recognized as high efficiency photocatalysts which can perform various redox reactions in aqueous or organic phases. We have experimentally proven that 2-BrAQ can undergo hydrogen transfer with an alpha-aromatic alcohol under light conditions, thereby efficiently oxidizing the aromatic alcohol to the corresponding product. The yield of 1-phenethanol to acetophenone can reach more than 96%. In subsequent catalyst screening experiments, it was found that the electronegativity of the substituent at the 2 position of the anthraquinone ring and the acidity of the solvent affect the photocatalytic activity of anthraquinones. After using various aromatic alcohol substrates, 2-BrAQ showed good conversion and selectivity for most aromatic alcohols, but showed C–C bond cleavage and low selectivity with non-α-position aromatic alcohols. In order to explore the mechanism of the redox reaction of 2-BrAQ in acetonitrile solution, the corresponding free radical reaction pathway was proposed and verified by density functional theory (DFT). Focusing on calculations for 2-BrAQ during the reaction and the first-step hydrogen transfer reaction between the 2-BrAQ triplet molecule and the 1-phenylethanol molecule, we recognized the changes that occurred during the reaction and thus have a deeper understanding of the redox reaction of anthraquinone compounds in organic systems.

Synthesis of 3,4-dihydroquinolin-2(1H)-one derivatives with anticonvulsant activity and their binding to the GABAA receptor

Shiben Wang,Hui Liu,Kang Lei,Guangyong Li,Jun Li,Yuyu Wei,Xuekun Wang,Renmin Liu

In this study, a series of 3,4-dihydroquinolin-2(1 H )-one derivatives were designed and synthesized using two experimental models, namely maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ), to test the anticonvulsant activity of the target compound in vivo (i.p. in Kunming mice). The neurotoxicity (NT) of the target compound was measured by the rotating rod method (i.p. in Kunming mice). Six compounds with potential activity were selected from the two experimental models to test the 50% effective dose (ED 50 ). In vitro binding experiments with the GABA A receptor were also performed. The results of the pharmacological experiments showed that compound 7-((5-(pentylthio)-1,3,4-oxadiazol-2-yl)methoxy)-3,4-dihydroquinolin-2(1 H )-one ( 5b ) showed the best anticonvulsant activity (MES, ED 50  = 10.1 mg/kg; scPTZ, ED 50  = 9.3 mg/kg), which was superior to activities shown by carbamazepine and ethosuximide, and it also exhibited the most potent binding affinity to GABA A receptors (IC 50  = 0.12 μM). The GABA content in Wistar rat brains (i.p.) was also investigated, and the results showed that compound 5b may have a certain effect on the GABA system, as it increased the GABA concentration in the brain of rats. Molecular docking was used to study the binding mode of compound 5b and the GABA A receptor. Compound 5b showed significant interactions with residues at the benzodiazepines binding site on the GABA A receptor. The physicochemical and pharmacokinetic properties of the target compounds were predicted using Discovery Studio 2019 and ChemBioDraw Ultra 14.0.

TRIM65 Promotes Invasion of Endometrial Stromal Cells by Activating ERK1/2/C-myc Signaling via Ubiquitination of DUSP6

Wu Ying-Ting,Ma Si-Yu,Sun Wen-Qin,Shen Wei-Wei,Zhu Hui-Ting,Zhang Qin,Chen Hui-Fen

BackgroundEndometriosis (EM) is a benign gynecological disease that shares some characteristics with malignancy, such as proliferation and invasion. So far, the pathogenesis of EM is still unclear. In this study, we investigated whether TRIM65 can play a role in the development of EM.MethodsTRIM65 expression levels in eutopic, ectopic, and normal endometrium were detected by quantitative real-time PCR and Western blot. Cell proliferation and invasion of primary endometrial stromal (EMS) cells were detected by CCK-8 and Transwell analysis. The interaction between TRIM65 and DUSP6 or C-myc was measured by coimmunoprecipitation, ubiquitylation, dual luciferase, and chromatin immunoprecipitation analysis.ResultsWe found that TRIM65 was identified as an up-regulated gene in ectopic endometrial tissues and EMS cells compared with control groups without EM. TRIM65 expression was positively correlated with the levels of p-ERK1/2, C-myc, matrix metalloproteinase-2, and integrin β1 in ectopic endometrial tissues in patients and mice. TRIM65 promoted the cell proliferation and invasion of EMS cells via the ERK1/2/C-myc pathway through ubiquitination of DUSP6. C-myc promoted TRIM65 expression through inducing TRIM65 promoter activity. Additionally, the increased expression of TRIM65, C-myc, matrix metalloproteinase-2, integrin β1, and p-ERK1/2 and the decreased expression of DUSP6 in ectopic endometrial tissues were significantly suppressed by inhibition of ERK1/2 signaling pathway in ectopic endometrial tissues in experimental mice model.ConclusionIn conclusion, TRIM65 promotes invasion of ectopic EMS cells by activating a feedback loop with the ERK1/2/C-myc signaling pathway and may be a potential therapeutic target for EM.

Smartphone-based photoelectrochemical biosensing system with graphitic carbon nitride/gold nanoparticles modified electrodes for matrix metalloproteinase-2 detection

Qingqing Zhang,Zetao Chen,Zhenghan Shi,Yaru Li,Zijian An,Xin Li,Jianzhen Shan,Yanli Lu,Qingjun Liu

Photoelectrochemical analysis has been widely used in the field of biosensing due to its high sensitivity and strong anti-interference ability. Herein, a portable and versatile smartphone-based photoelectrochemical biosensing platform was developed for the rapid and on-site biomedical analysis. In the system, light excitation and photocurrent measurements were accomplished by a miniaturized and integrated circuit board. Smartphone with a specifically designed application was utilized to wirelessly control the system via Bluetooth. For photoelectrochemical sensor, graphitic carbon nitride (g-C 3 N 4 ) and gold nanoparticles loaded on indium tin oxide electrodes were utilized as photoactive materials and signal amplification elements, respectively. The gold nanoparticles were also used to immobilized matrix metalloproteinase-2 (MMP-2) specific cleavage peptide that modified with bovine serum albumin (BSA) on the terminal. In the presence of MMP-2, the peptide was specifically hydrolyzed and cleaved. Thus, parts of the peptide chain and BSA were detached from the electrode resulting in the decrease of steric hindrance and the increase of photoelectrochemical currents. The photocurrents changed linearly with the logarithm of MMP-2 concentrations ranging from 1 pg/mL to 100 ng/mL in both buffer and artificial serum with correlation coefficient of 0.9943 and 0.9698. The limit of detections were as low as 0.48 pg/mL in buffer and 0.55 pg/mL in artifical serum. It indicated that the biosensor has good linearity and high sensitivity, which also verified the effectiveness of the portable instrument. This system provides a pioneering solution for the development of miniaturized and portable photoelectrochemical analysis instruments used for the field monitoring of different analytes .

Amide Gemini surfactants linked by rigid spacer group 1,4-dibromo-2-butene: Surface properties, aggregate and application properties

Weiguang Yang,Yupeng Cao,Hongbin Ju,Yakui Wang,Yajie Jiang,Tao Geng

Novel amide Gemini surfactants were synthesized from aliphatic acid amide propyl dimethylamine (PKO-12, 16, 18) and trans-1,4-dibromo-2-butene with one-step reaction. The steady-state surface tension, dynamic surface tension, and interfacial tension of kerosene surfactant solutions of synthesized Gemini surfactants with different hydrophobic chain lengths were studied and compared. Besides, surface tension, and negative staining TEM methods were applied to study the aggregation properties of synthesized Gemini surfactants in the aqueous medium. Also, it was revealed that the Gemini surfactants possess good antistatic and antibacterial properties.