Science Advances
·
2025
·Vol. 11
·期 29
·
IF 12.5
Zhenyu Li,Kunhong Jiang,Yue Yang,Yijing Pian,Huizhen Liu,Zexuan Zheng,Xiyang Wang,Subhajit Jana,Jiefei Li,Zhuoyuan Ma,Xiaoyun Qiao,Xiaoxin Zou,Xuelu Ma,Bin Zhang,Haibin Chu,Yimin A. Wu
Glycerol oxidation reaction (GOR) represents an economical pathway for transforming renewable feedstock to value-added chemicals. However, the inertness of C(sp 3 )─H bonds of glycerol and intermediates results in the high energy barrier of the dehydrogenation step, relating to poor product selectivity at high glycerol conversion. Here, a carbon nanotube–supported PdBO x @Pd heterostructure catalyst (PdBO x @Pd/CNTs) was synthesized in which in situ–exsoluted PdBO x clusters covalently covered Pd nanoparticles, thus yielding strong electronic interaction between Pd nanoparticles and PdBO x clusters. The strong electronic interaction in PdBO x @Pd/CNTs induces the hybridization between Pd(d), B(s, p), and O(s, p) atom orbits, optimizing the adsorption of reactants and intermediates, thus enhancing the activity for the GOR. The density functional theory calculation result reveals that the strong electronic interaction in PdBO x @Pd/CNTs facilitates the hydrogen transfer in the primary C─H bond of the CH 2 OHCHOHCH 2 O* intermediate, thus reducing the energy barrier of the rate-determining step and improving glyceric acid selectivity toward the GOR.
研究领域:
催化
·
材料科学
·
化学反应工程
·
理论化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELL BIOLOGY INTERNATIONAL
·
2024
·
IF 3.3
Guang Yang,Xin Shi,Meixia Zhang,Kaiwen Wang,Xin Tian,Xiaofeng Wang
Oral squamous cell carcinoma (OSCC) is the most common oral malignancy. DEAD/H-box helicase 11 (DDX11), a DNA helicase, has been implicated in the progression of several cancers. Yet, the precise function of DDX11 in OSCC is poorly understood. The DDX11 expression in OSCC cells and normal oral keratinocytes was evaluated in the Gene Expression Omnibus database (GSE146483 and GSE31853). SCC-4 and CAL-27 cells expressing doxycycline-inducible DDX11 or DDX11 shRNA were generated by lentiviral infection. The role of DDX11 in OSCC cells was determined by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, colony formation assay, flow cytometry assay, TUNEL staining, and western blot. The effects of DDX11 on tumor growth were explored in a xenograft nude mouse model. The relationship between DDX11 and transcription factor Yin Yang-1 (YY1) was researched using the dual luciferase report assay and chromatin immunoprecipitation assay. DDX11 expression was significantly upregulated in OSCC cells. Knockdown of DDX11 inhibited cell proliferation, induced cell cycle arrest, and suppressed PI3K-AKT pathway, while DDX11 overexpression showed opposite effects. The number of apoptotic cells was increased in DDX11 silenced cells. DDX11 upregulation or knockdown accelerated or suppressed tumor growth in vivo, respectively. Moreover, the YY1 bound and activated the DDX11 promoter, resulting in increasing DDX11 expression. Forced expression DDX11 reversed the anticancer effects of YY1 silencing on OSCC cells. DDX11 has tumor-promoting function in OSCC and is transcriptionally regulated by YY1, indicating that DDX11 may serve as a potential target for the OSCC treatment.
研究领域:
肿瘤学
·
分子生物学
·
细胞生物学
·
转化医学
✓ 已验证
DOI
PubMed
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-12
·
IF 15.7
Hu Yaqi,Liu Runze,Lu Kaiyun,Wu Daoning,Gao Pan,Hou Guangjin,Zhang Hongbo,Dai Weili
Hydrated hydronium ions formed in the pores/cages of zeolite catalysts are suggested as the active species that could impact the adsorption of reactant, the stability of intermediates or transition states, and the reaction mechanism in the aqueous phase alcohol dehydration. Nevertheless, under a typical vapor phase reaction condition, the relevant situation is still debatable. Herein, the promotion of water on cyclohexanol (CyOH) adsorption and dehydration under a vapor phase condition was clarified by in situ 1 H MAS NMR, 2D 1 H DQ MAS NMR and 2D 1 H- 27 Al HMQC NMR spectroscopy, systematic kinetic studies, isotope tracing and thermodynamic measurements. The water promoting effects were ascribed to water facilitating the formation of H 3 O + cluster (H 3 O + (H 2 O) n-1 ), and per Brønsted acid site (BAS) could be saturated by about 5 water at ambient temperature. The CyOH dehydration pathway was found to be highly dependent on the water concentrations, and a dimer reaction route with the C-H bond rupture as the kinetically relevant step (KRS) was verified as the main reaction pathway at high water concentrations. All these findings provide the deep insights into how water regulating the zeolite catalyzed dehydration reaction at a molecular level.
研究领域:
催化化学
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物理化学
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材料科学
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核磁共振波谱学
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反应机理
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表面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2023
·
IF 3.6
Shuo Li,Xian Xu,Qianlin Sun,Xin Xu
This work reports an intramolecular C(sp3)–H annulation of functionalized 2,6-lutidines catalyzed by an organocalcium hydride [{(DIPPnacnac)CaH(thf)}2] (DIPPnacnac = CH{(CMe)(2,6-iPr2–C6H3N)}2). This reaction constitutes a streamlined approach for producing a new family of tetrahydro-1,5-naphthyridines and hexahydropyrido[3,2-b]azocines derivatives in good to excellent yields with high atom efficiency and broad substrates scope. A calcium alkyl complex was isolated from the stoichiometric reaction between calcium hydride and the substrate through deprotonation, which was structurally characterized and confirmed as the catalytic intermediate.
研究领域:
有机化学
·
催化
·
合成化学
✓ 已验证
DOI
高影响因子
Science China-Chemistry
·
2022
·Vol. 66
·期 2
·548-561
·
IF 10.138
Zhao Ying-Han,Li Wenhao,Shen Tao,Zhao Yan,Liu Yunqi,Wang Yang
The development of readily accessible high-mobility n-type semiconducting polymers is in great demand for realizing high-performance p-n junction-based organic electronics. In this study, we demonstrate that with the combination of dual-acceptor strategy and C-H direct arylation polymerization (DArP), unipolar n-type semiconducting polymers can be conveniently synthesized. By tuning the monomer concentration, three dual-acceptor polymers, namely, poly(naphthalene diimide- alt -dithiophenyl pyrrolopyrrole-dione) (PNDI-DPP), poly(naphthalene diimide- alt -dithiophenyl isoindigo) (PNDI-IID), and poly (naphthalene diimide- alt -dithiophenyl bezothiadiazole) (PNDI-BT) can be obtained via C-H activation with decent number average molecular weight of ∼10 to 30 kg mol −1 and relatively narrow polydispersity index of ∼2. In addition, these polymers are defect-free in nature as evidenced by the nuclear magnetic resonance. Moreover, we attribute the different molar masses of the three copolymers under the same DArP condition to the different α-C-H acidity, which may stem from different electron-withdrawing capability of the hydrogenated acceptor units. Furthermore, the influence of the hydrogenated acceptor monomers on the optical, electrochemical and charge transporting properties is comprehensively studied. Among the three dual-acceptor polymers, PNDI-BT demonstrates the highest electron mobilities of up to 0.6 cm 2 V −1 s −1 in unipolar n-type organic transistors because of its relatively planar backbone, larger overlaps of the lowest unoccupied molecular orbital and strong H-aggregation. Note that the transistor performance of PNDI-BT synthesized via C-H activation in this study is at least comparable to the one made by conventional C(sp 2 )-C(sp 2 ) Stille or Suzuki cross-coupling polymerization. This study demonstrates the presented protocol can be a useful platform for sustainable and convenient synthesis of high-performance n-type semiconducting polymers.
研究领域:
材料科学
·
有机电子学
✓ 已验证
DOI
高影响因子
GREEN CHEMISTRY
·
2021
·Vol. 24
·期 1
·384-393
·
IF 10.182
Qi Zhang,Shouxin Liu,Xia Tian,Yidong Liu,Shiming Fan,Baibiao Huang,Andrew Whiting
A highly selective, green and sustainable chlorination of aliphatic C–H bonds is reported using MCln under the co-catalysis of visible light and nano-Cu@CuCl, which was synthesised via a one-step, hydrothermal strategy using copper(II) sulfate and D-glucose as the reducing agent in a KCl solution. A novel cascade method of producing Cl2 occurs in situ chlorinating C(sp3)–Hs, achieved through nano-Cu@CuCl catalysis using inorganic chloride MCln as a chlorine source under visible light and without the need for a strong oxidant. The reaction was applied to the chlorination of different alkylarene α-Hs and cyclic hydrocarbons C–HS and was developed for use in a photocatalytic serial reactor system which accomplished the chlorination of toluene α-Hs to give 92% conversion, 90% yield and 98% selectivity. Electron spin resonance (ESR) studies of DMPO-Cl. revealed that the reaction mechanism belonged to a free radical process.
研究领域:
有机化学
·
绿色化学
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材料科学
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2022
·
IF 3.574
Feifei Zhou,Ganghua Pan,Haining Meng,Hailong Sun
For preparing finer and well-dispersed calcium-silicate-hydrate (C-S-H) seeds at a lower cost, the waste solution of acid treatment of recycled concrete aggregates (RCAs) and black liquor from pulping were used for the synthesis of C-S-H seeds. The results show that C-S-H seeds can be successfully fabricated by chemical co-precipitation reaction using the two waste solutions. Interestingly, it was globular rather than traditional foil-like. Furthermore, C-S-H seeds synthesized using the two waste solutions had smaller particle size and better dispersibility. More importantly, it had a more prominent accelerating effect to the strength development of mortar, significantly enhancing the early and long-term compressive strength of mortar.
研究领域:
材料科学
·
土木工程
·
环境科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Yuhui Fu,Lijuan Dai,Sisi Wei,Yuxin Fang,Zhe Zhang,Hongtao Zhu,Tongwei Zhang,Lianmei Zhao,Baoen Shan
Esophageal squamous cell carcinoma (ESCC) represents a globally prevalent malignancy characterized by a poor prognosis, largely due to the challenges that patients face in tolerating invasive diagnostic procedures. Therefore, it is imperative to explore strategies to enhance the early diagnostic rate for patients with ESCC. Based on the property of H-chain ferritin-based magnetic ferritin nanoparticles (M-HFn) as contrast agents that can target cluster of differentiation 71 (CD71), this study provides a comprehensive evaluation of the expression levels and diagnostic potential of CD71 to investigate the feasibility of utilizing M-HFn for non-invasive diagnosis. Following the synthesis and the characterization of M-HFn, an orthotopic mouse model is developed to simulate the progression of ESCC. Subsequently, magnetic resonance imaging (MRI) scans are conducted after administering M-HFn to the mice. The results indicate a progressive increase of CD71 expression in tissues, transitioning from normal epithelium to esophageal squamous precancerous lesions (ESPL) and ultimately to ESCC. M-HFn injected into the mice selectively target cells with heightened CD71 expression, resulting in accumulation at the lesion sites. Consistent with pathological diagnoses, MRI images demonstrate a reduction in signal intensity at the lesion site in T 2 -weighted sequences, thereby facilitating the visualization of ESCC and ESPL. CD71 demonstrates high accuracy and specificity as a diagnostic target, positioning M-HFn-mediated targeted diagnostic strategy as a promising approach for the early detection of ESCC, with the potential to significantly improve patient prognosis.
研究领域:
肿瘤学
·
纳米医学
·
诊断影像学
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分子靶向治疗
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ORGANOMETALLICS
·
2020
·
IF 3.804
Liangwei Zhang,Long Liu,Tianzeng Huang,Qizhi Dong,Tieqiao Chen
A palladium-catalyzed cyclobutanation of aryl sulfonates with strained alkenes has been developed. The methodology is featured to achieve the cleavage of both C–O and C–H bonds of phenol derivatives in one pot. Under the reaction conditions, in addition to reactive triflates, the relatively inactive tosylates and mesylates can also be transformed into the corresponding benzocyclobutanes in high yields. This reaction can be carried out in gram-scale experiments with a low loading of the palladium catalyst and is applicable to the cyclobutanative modification of bioactive molecules, highlighting its synthetic value in organic synthesis.
研究领域:
有机化学
·
催化化学
·
合成化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Ping Ye,Weimiao Wang,Xiaodong Li,Zhiqiang Qiao,Yirui Lu,Bing Huang,Liangfei Bai,Liang Chen,Xiaoqing Tu,Rui Li,Guangcheng Yang,Guoqing Lv
Although laser ignition is considered to be one of the most promising ways to detonate energetic materials due to its high safety and reliability, it is still a challenge to achieve direct ignition of energetic materials by a laser with low-power and near-infrared (NIR) band. In this paper, a molecular self-assembly strategy based on recrystallization was utilized to prepare 4,4′,5,5′-tetranitro-1H,1′H-[2,2′-biimidazole]-1,1′-diamine (DATNBI) crystals with various micro-nano structures. The characterization results suggest that DATNBI crystals with different degrees of roughness and defects by the induction of solvents and surfactants. The crystal defects can not only bring about the enhancement of light absorption of DATNBI in NIR band, but also advance its thermal decomposition, providing reliable support for direct laser ignition of DATNBI profit from the hot spot ignition theory. Combined with density functional theory, it is speculated that electrons of defect states achieve electron-hole recombination by laser radiation, thereby enhancing photothermal conversion. Compared with raw DATNBI, DATNBI crystals with rough surface and abundant defects can be directly ignited by a NIR laser and exhibits self-sustainable combustion. In summary, a direct NIR laser-ignitable energetic material has been prepared via appropriate crystal structure design.
研究领域:
材料科学
·
光学工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MedChemComm
·
2013
·Vol. 5
·期 2
·147-152
·
IF 2.722
Haiqing Dong,Chunyan Dong,Wenjuan Xia,Yongyong Li,Tianbin Ren
A novel prodrug of pegylated methotrexate conjugates (PMCs) with a high drug-carrying capability and a redox sensitive drug release mechanism was reported for intracellular drug delivery. The PMC was structured in a H-shape with four molecules of anticancer drug methotrexate (MTX) linked to both ends of the PEG main chain via disulfide linkers, resulting in the conjugates with a high and constant drug loading efficiency of up to 26 wt%. The amphiphilic property of PMCs enables them to self-assemble into nanoparticles in aqueous solution, while the cleavable disulfide linkers allow the conjugated MTX to exert its therapeutic activity due to the fast cleavage of disulfide linkers when exposed to the intracellular concentration of glutathione (GSH). Cell proliferation assays performed with HepG2 cancer cells confirmed the pharmacological efficacy.
研究领域:
药理学
·
癌症研究
·
纳米医学
·
药物递送系统
✓ 已验证
DOI
高影响因子
Advanced Science
·
2024
·
IF 14.3
Lijiao He,Xiao Zhang,Shengwei Zhang,Yi Wang,Weichao Hu,Jie Li,Yunyi Liu,Yu Liao,Xue Peng,Jianjun Li,Haiyan Zhao,Liting Wang,Yang-Fan Lv,Chang-Jiang Hu,Shi-Ming Yang
Persistent H. pylori infection triggers the repair program of the mucosa, such as spasmolytic polypeptide-expressing metaplasia (SPEM). However, the mechanism underlying the initiation of SPEM in gastric tissues by H. pylori remains unclear. Here, an increase in telomerase reverse transcriptase (TERT) protein expression is observed in chief cells upon infection with cagA -positive H. pylori . Tert knockout significantly ameliorated H. pylori -induced SPEM and single-cell RNA sequencing demonstrated that the Wnt/β-Catenin pathway is suppressed in gastric cells with Tert knockout. Mechanism study revealed that CagA elevated TERT abundance by disrupting the interaction between TERT and its novel E3 ligase, SYVN1. Interestingly, Nitazoxanide effectively relieved SPEM via inhibition of the Wnt/β-Catenin signaling in vivo. This results clarified the mechanism underlying which CagA activated the TERT/Wnt/β-Catenin pathway, thus promoting the dedifferentiation of chief cells and the occurrence of SPEM in gastric mucosa. This highlights a molecular basis for targeting CagA-activated Wnt signaling in chief cells for the treatment of gastric precancerous lesions.
研究领域:
胃肠病学
·
分子生物学
·
肿瘤学
·
病理学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）