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m4C DNA methylation regulates biosynthesis of daptomycin in Streptomyces roseosporus L30

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Synthetic and Systems Biotechnology 2022年第4期7卷 1013-1023页

作者： Jiao-Le Fang Wen-Li Gao wei-Feng Xu Zhong-Yuan Lyu Lie Ma Shuai luo Xin-Ai Chen Xu-Ming Mao Yong-Quan Li Institute of Pharmaceutical Biotechnology Zhejiang University School of MedicineHangzhou310058PR China Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering 310058HangzhouPR China

Despite numerous studies on transcriptional level regulation by single genes in drug producing Actinomyces,the global regulation based on epigenetic modification is not well explored.N4-methylcytosine(m4C),an abundant epigenetic marker in Actinomycetes’genome,but its regulatory mechanism remains *** this study,we identify a m4C methyltransferase(SroLm3)in Streptomyces roseosporus L30 and multi-omics studies were performed and revealed SroLm3 as a global regulator of secondary ***,three BGCs inΔsroLm3 strain exhibited decreased expression compared to wild ***-frame deletion of sroLm3 in *** L30 further revealed its role in enhancing daptomycin *** summary,we characterized a m4C methyltransferase,revealed the function of m4C in secondary metabolism regulation and biosynthesis of red pigment,and mapped a series of novel regulators for daptomycin biosynthesis dominated by m4C *** research further indicated that m4C DNA methylation may contribute to a metabolic switch from primary to secondary metabolism in Actinomyces.

关键词： N4-methylcytosine DNA methyltransferase Daptomycin Transcriptional regulator Secondary metabolism

The existence of identity of periodic semigroup rings

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Chinese Science Bulletin 1997年第7期42卷 614-615页

作者： Yang, HX luo, YF LANZHOU UNIV DEPT MATHLANZHOU 730000PEOPLES R CHINA

IN ref. [1], Ponizovskiǐ raised the following problem: which semigroup rings are rings with identity? In ref. [2], Li investigated orthodox semigroup rings. In this letter we discuss periodic semigroup rings. Using t... 详细信息

关键词： The existence of identity of periodic semigroup rings

Hollow Bio-derived Polymer Nanospheres with Ordered Mesopores for Sodium-Ion Battery

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Nano-Micro Letters 2020年第3期12卷 1-11页

作者： Yan Ai Yuxiu You Facai wei Xiaolin Jiang Zhuolei Han Jing Cui Hao luo Yucen Li Zhixin Xu Shunqi Xu Jun Yang Qinye Bao Chengbin Jing Jianwei Fu Jiangong Cheng Shaohua Liu State Key Laboratory of Precision Spectroscopy and Department of Materials School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241People’s Republic of China Department of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Center for Advancing Electronics Dresden(cfaed)and Department of Chemistry and Food Chemistry Technische Universität Dresden01062 DresdenGermany School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450052People’s Republic of China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050People’s Republic of China

Bio-inspired hierarchical self-assembly provides elegant and powerful bottom-up strategies for the creation of complex ***,the current self-assembly approaches for natural bio-compounds often result in materials with limited diversity and complexity in architecture as well as ***,we develop a novel coordination polymerization-driven hierarchical assembly of micelle strategy,using phytic acid-based natural compounds as an example,for the spatially controlled fabrication of metal coordination bio-derived *** resultant ferric phytate polymer nanospheres feature hollow architecture,ordered meso-channels of^12 nm,high surface area of 401 m2 g−1,and large pore volume of 0.53 cm3 g−*** an advanced anode material,this bio-derivative polymer delivers a remarkable reversible capacity of 540 mAh g−1 at 50 mA g−1,good rate capability,and cycling stability for sodium-ion *** study holds great potential of the design of new complex bio-materials with supramolecular chemistry.

关键词： Self-assembly Biomimetic synthesis Mesoporous polymer Ferric phytate Sodium-ion battery

Impact of Pulmonary Vein Anatomy on Long-term Outcome of Cryoballoon Ablation for Atrial Fibrillation

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Current Medical Science 2018年第2期38卷 259-267页

作者： Shang-wei HUANG Qi JIN Ning ZHANG Tian-you LING Wen-qi PAN Chang-jian LIN Qing-zhi luo Yan-xin HAN Li-qun WU Department of Cardiology Shanghai Ruijin Hospital Shanghai Jiao Tong University School of Medicine Shanghai20025 China

Variant pulmonary vein anatomy （PVA） has been reported to influence the recurrence of atrial fibrillation （AF） after radiofrequency ablation. However, the effects of PVA on AF in patients undergoing cryoballoon ablation （CBA） remain unknown. The present study aimed to examine the impact of PVA on the long-term outcome of CBA for AF. A total of 78 patients （mean age 60.7±10.9 years, 64.1% males） with symptomatic and drug-refractory paroxysmal AF were enrolled in the study. Left atrium （LA） and PVA acquired at computed tomography angiography （CTA） were reconstructed with CARTO 3 SYSTEM. Patients were routinely evaluated by 24-hour Holter monitoring following CBA. Cox regression was used to detect the predictors of AF recurrence after CBA. The results showed abnormal PVA in 30 patients （38.5%） and 18 patients （23.1%） had left common PV （LCPV）. Electrical pulmonary vein isolation was achieved in all patients. After a mean follow-up of 689.5±103.8 days, it was found that patients with abnormal PVA had similar AF recurrence rate to those with normal PVA （26.7% vs. 25.0%, P=0.54）, and there was no significant difference in AF recurrence rate between LCPV patients and non-LCPV patients （33.7% vs. 23.3%, P=0.29）. Cox regression analysis showed that AF duration （72.9±9.0 vs. 42.3±43.2 months, HR 1.001; 95%CI 1.003- 1.014; P〈0.001） and cryo-applications of right-side PVs （3.0±1.6 vs. 4.7±1.7, HR 0.661; 95% CI 0.473-0.925; P=0.016） were independent predictors of freedom from AF, but PVA was not identified as a predictor of long-term success. In conclusion, the variant PVA cannot significantly influence the long-term outcome of AF patients undergoing CBA; longer AF duration and less cryo-applications of right-side PVs are associated with higher AF recurrent rate.

关键词： atrial fibrillation pulmonary vein anatomy cryoballoon ablation

MODELING ON DYNAMIC PROCESS OF MEMBRANE FOULING DURING FINITE CROSSFLOW ULTRAFILTRATION IN CHARGED SYSTEM

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Journal of Hydrodynamics 2006年第2期18卷 206-210页

作者： luo Ming-Liang PU Chun-sheng ZHAO Jian-qing College of Petroleum Engineering China University of Petroleum （East China） Dongying 257061 China College of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

Flux decline during finite crossflow Ultrafiltration（UF） in charged system was investigated by perceiving membrane fouling as a dynamic process from non-equilibrium to equilibrium. Under the influence of the boundary condition at the initial section and cross flow, the equilibrium is first reached at the initial section of the crossflow filter and the front of the equilibrium region progresses with time toward the end of the filter. A mathematic model was developed to describe this dynamic process of membrane fouling in a charged system. With the model, the time-dependent flux and the time required to reach the steady state in a crossflow filtration can be easily determined. The fouling process under different conditions is simulated as illustrated with a demonstration of the newly developed model. The resulls of simulation show that there are jumps in the local flux at the front of the equilibrium region and the electrokinetic properties of charged UF system have a very substantial influence on the separation performance of membrane.

关键词： fouling dynamics flux decline,Ultrafiltration(UF) charged system modeling

Role of Suprapermafrost Groundwater Recharge in Dissolved Organic Carbon Dynamics of Thermokarst Lakes

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Journal of Earth Science 2024年第6期35卷 2175-2179页

作者： Zeyong Gao Fujun Niu Dongliang luo Yibo Wang Jing luo Guoan Yin Yunhu Shang Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai200234China College of Earth and Environment Sciences Lanzhou UniversityLanzhou730000China

0 INTRODUCTION The Sixth Assessment Report of the Intergovernmental Panel on Climate Change(IPCC AR6)indicated that the global surface temperature had risen by approximately 1.09℃compared to the 1850-1900 average over the past decade(IPCC,2021).The warming rate of air temperature in polar and high-elevation permafrost regions was found to be about two times higher than the average global warming rate(Liu et al.,2023;Hu et al.,2021).

关键词： warming karst global

Enhanced photothermal dehydration of methanol over W_(18)O_(49)/Au/SAPO-34 catalysts with broadened light absorption

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Rare Metals 2024年第3期43卷 1139-1152页

作者： Ya-Qin Tang Meng-Xia Yan Chang-Qian Lu Shao-Yuan Li Kui-Xian wei Tao Qu Wen-HuiMa Yong-Nian Dai Kong-Zhai Li Da-Jun luo Xue-Liang Zhang Yi-Ke Liu Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China School of Materials and Energy Engineering Guizhou Institute of TechnologyGuiyang550003China

Methanol-to-olefins(MTO)process is one of the most critical pathways to produce low carbon ***,the reaction is driven by thermal catalysis,which inevitably needs to consume large amounts of fossil *** a new technique to substitute for the fuel burning is urgent for MTO process to improve the industry prospects and ***,we report a novel W_(18)O_(49)/Au/SAPO-34(W/Au/S),a multifunctional photothermal catalyst for the MTO reaction.A high methanol conversion was achieved under xenonum(Xe)lamp irradiation,yielding methyl ether(ME)and ethylene as the main *** optimized W/Au/S catalysts showed ethylene yield as high as 250μmol in 60 min,which was 2.5 times higher than that of Au/*** physiochemical characterization revealed that the SAPO-34 molecular sieves were surrounded by Au and W_(18)O_(49)nanoparticles,which exhibited a strong localized surface plasmon resonance excitation around 540 nm and light absorption beyond 500 *** multifunctional catalysts showed a strong photothermal effect,arising from the broadened light absorption of Au and W_(18)O_(49)nanoparticles,leading to a temperature as high as 250℃on the surface of the *** study showed that the superior ethylene selectivity of W/Au/S catalysts was attributed to the moderating acidic sites of W_(18)O_(49)for methanol dehydration to *** research may provide new insight for designing heterostructures to improve photo-to-chemical conversion performance and is expected to accelerate progress toward the excellent multifunctional photothermal catalysts with broad light absorption for methanol activation and C-C bond formation.

关键词： Methanol conversion Ethylene Photothermal catalysis W_(18)O_(49) BrΦnsted-acid

Oral delivery of ferroptosis inducers for effective treatment of hepatic fibrosis

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Nano Research 2024年第8期17卷 7621-7630页

作者： Yinglan Yu Shunlong Zhang Yongfeng Xu Hao Shao Lei luo College of Pharmaceutical Sciences Southwest UniversityChongqing 400715China

Liver fibrosis is characterized by the excessive accumulation of extracellular matrix(ECM),which is primarily produced by activated hepatic stellate cells(HSCs).However,effective therapies for hepatic fibrosis are currently *** is a promising anti-fibrotic drug candidate,but its clinical application is hindered by limited ***,we present a novel oral delivery platform that enhances the HSCs uptake of artesunate and induces potent *** platform is vitamin Adecorated nanoparticles encapsulated with *** multifunctional ligand vitamin A interacts with retinol-binding proteins that are highly expressed on the intestinal epithelium to promote transcytosis,highly expressed on the surface of HSCs but lowly expressed in normal *** oral administration,this oral delivery platform enhances transepithelial transport in the intestine,improves drug accumulation in the liver,and continuously increases HSCs uptake of *** drug release in HSCs,artesunate depletes glutathione peroxidase 4 and glutathione,effectively initiating *** vivo experiments demonstrate that this strategy induces pronounced ferroptosis,efficiently relieving liver *** work provides a proof-ofconcept demonstration that an oral delivery strategy for ferroptosis inducers may be beneficial for liver fibrosis treatment.

关键词： liver fibrosis hepatic stellate cells oral delivery intestinal epithelium ferroptosis

Molecular behaviors in thin film lubrication——Part one: Film formation for different polarities of molecules

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Friction 2019年第4期7卷 372-387页

作者： Shaohua ZHANG Yijun QIAO Yuhong LIU Liran MA Jianbin luo State Key Laboratory of Tribology Tsinghua UniversityBeijing100084China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of ControlEngineeringBeijing100094China

There are three unsolved problems in thin film lubrication(TFL) since it was proposed 20 years ago, i.e., the determination of the type of molecules that can enter the contact region efficiently during sliding, the orientation of molecules in the contact region, and the effect of solid surfaces on the liquid molecular orientation in TFL. In order to answer the first two questions, an in situ measurement system comprising a self-designed Raman microscopy and relative optical interference intensity(ROⅡ) system was set up to study the molecular behaviors. A variety of binary mixtures were used as lubricants in the test, and the concentration distribution profile and orientation of the additive molecules in TFL were characterized. The molecular behavior was determined via a combination of shearing, confinement, and surface adsorption. Furthermore, the difference in molecular polarity resulted in different competing effect of surface adsorption and intermolecular interaction, the influence of which on molecular behavior was discussed. Polar additive molecules interacted with the steel surface and exhibited an enrichment effect in the Hertz contact region when added into a nonpolar base oil. No enrichment effect was observed for nonpolar molecules that were added into the nonpolar base oil and polar molecules added into polar base oil. The enrichment of additive molecules enhanced the film-forming ability of the lubricant and resulted in a reduction in the friction coefficient of up to 61%. The orderly arrangement of the additive molecules was another reason for the friction-reducing. A binary multilayer model was proposed to illuminate the molecular behavior in the TFL, and the model was supported by contrary experiment results in elastohydrodynamic lubrication. This research may aid in understanding the nanoscale lubrication mechanism in TFL and the development of novel liquid lubricants.

关键词： thin film lubrication in situ Raman spectroscopy molecular distribution molecular orientation