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Decline and fall of aging astrocytes:the human perspective

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Neural Regeneration Research 2025年第6期20卷 1713-1714页

作者： Alexei Verkhratsky Alexey Semyanov Faculty of biology Medicine and HealthThe University of ManchesterManchesterUK Department of Neurosciences University of the Basque Country UPV/EHU and CIBERNEDLeioaSpain Department of Forensic Analytical Toxicology School of Forensic MedicineChina Medical UniversityShenyangLiaoning ProvinceChina Department of Stem Cell biology State Research Institute Centre for Innovative MedicineVilniusLithuania International Collaborative Center on Big Science Plan for Purinergic Signalling Chengdu University of Traditional Chinese MedicineChengduSichuan ProvinceChina Department of Physiology Jiaxing University College of MedicineJiaxingZhejiang ProvinceChina

“Last scene of all that ends this strange,eventful history,is second childishness and mere oblivion.I am sans teeth,sans eyes,sans taste,sans everything.”William Shakespeare‘As You Like It'Act 2,Sc.7,l.139Aging of the human brain is characterized by a progressive decline of its functional capacity;this decline however varies widely,and cognitive longevity differs substantially between individuals.

关键词： aging teeth progressive

Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期68卷 308-316页

作者： Sili Wang Jiancheng Huang Yanan Du Wei Huang Yufeng Xue Xiaokun Xu Guannan Zhong Yuanyuan Shi Bin Hong Xiaoying Bian Wen Liu State Key Laboratory of Chemical biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

关键词： cbl-dependent radical SAM protein biosynthesis chuangxinmycin stereoselective methylation

IN SITU COMPATIBILIZATION OF LDPE/NYLON-6 BLEND USING LOW MOLECULAR WEIGHT INTERFACIAL AGENT AS A CHEMICAL COMPATIBILIZER

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Chinese Journal of Polymer Science 1997年第3期15卷 205-216页

作者：李蓓张瑞丰蔡忠龙 Department of applied biology and Chemical Technology Department of applied Physics the Hong Kony Polytechnic University Hung Hom Kowloon Hong Kong

In situ, compatibilization of low density polyethylene (LDPE) (30%) and nylon-6 (70%) blends through one-step reactive extrusion using t-BuOOH as an initiator and low molecular weight interfacial agents as compatibilizers was studied. The compatibilizer contained a long chain hydrocarbon, double bond and two polar functional groups which was capable of reacting with both LDPE and nylon-6 in the presence of initiator to form a copolymer at the interface of the two polymer phases. The extruded blends exhibited significant enhancement in their compatibility based on morphological, thermal analysis and mechanical studies. The effect of the hydrocarbon chain length and structure of the functional group of the compatibilizer was also examined. It was found that blends prepared by using the compatibilizer containing longer hydrocarbon chain and amide group had better mechanical properties.

关键词： LDPE nylon-6 reactive extrusion compatibilizer

Therapeutic targeting of cellular prion protein: toward the development of dual mechanism anti-prion compounds

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Neural Regeneration Research 2025年第4期20卷 1009-1014页

作者： Antonio Masone Chiara Zucchelli Enrico Caruso Giovanna Musco Roberto Chiesa Laboratory of Prion Neurobiology Department of NeuroscienceIstituto di Ricerche Farmacologiche Mario Negri IRCCSMilanItaly Biomolecular NMR Unit Division of Genetics and Cell BiologyIRCCS Ospedale San RaffaeleMilanItaly Department of Biotechnology and Life Sciences University of InsubriaVareseItaly

PrPSc,a misfolded,aggregation-prone isoform of the cellular prion protein(PrPC),is the infectious prion agent responsible for fatal neurodegenerative diseases of humans and other *** adopt different pathogenic conformations(prion strains),which can be resistant to potential drugs,or acquire drug resistance,posing challenges for the development of effective *** PrPCis the obligate precursor of any prion strain and serves as the mediator of prion neurotoxicity,it represents an attractive therapeutic target fo r prion *** this minireview,we briefly outline the approaches to target PrPCand discuss our recent identification of Zn(Ⅱ)-Bn PyP,a PrPC-targeting porphyrin with an unprecedented bimodal mechanism of *** argue that in-depth understanding of the molecular mechanism by which Zn(Ⅱ)-Bn PyP targets PrPCmay lead toward the development of a new class of dual mechanism anti-prion compounds.

关键词： anti-prion drug anti-PrPC antibody antisense oligonucleotide neurodegeneration pharmacological chaperone porphyrin prion disease PrPC degrader PrPC shedding zinc finger repressor

A review:Advances in microbial remediation of trichloroethylene (TCE)

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Journal of Environmental Sciences 2010年第1期22卷 116-126页

作者： Prabhakar Pant Sudhakar Pant applied Research Center Florida International University Department of biology St. Xavier's College

Research works in the recent past have revealed three major biodegradation processes leading to the degradation of trichloroethylene. Reductive dechlorination is an anaerobic process in which chlorinated ethenes are used as electron acceptors. On the other hand, cometabolism requires oxygen for enzymatic degradation of chlorinated ethenes, which however yields no benefit for the bacteria involved. The third process is direct oxidation under aerobic conditions whereby chlorinated ethenes are directly used as electron donors by microorganisms. This review presented the current research trend in understanding biodegradation mechanisms with regard to their field applications. All the techniques used are evaluated, with the focus being on various factors that influence the process and the outcome.

关键词： biodegradation trichloroethylene reductive dechlorination cometabolism direct oxidation

The Susceptibilities of Oxya chinensis(Orthoptera:Acridoidea) to Malathion and Comparison of the Esterase Properties from Three Collected Populations in Tianjin Area,China

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Agricultural Sciences in China 2009年第1期8卷 76-82页

作者： WU Hai-hua YANG Mei-ling GUO Ya-ping MA En-bo Institute of applied biology Shanxi University Taiyuan 030006 P.R.China

The susceptibilities of Oxya chinensis to malathion were studied in three populations collected from outskirt of Tianjin, China, using bioassays and biochemical analysis. Populations were chosen to represent different exposure to insecticides： BDG （Beidagang; low exposure）, BD （Baodi; high exposure previously but low exposure now）, and JN （Jinnan; high exposure）. The results showed that the LD50 values of BD and JN populations were 3.95- and 12.02-fold and 3.64- and 10.07- fold higher than that of BDG population in females and males, respectively. The LD50 values in females were higher than those in males. The results of biochemical analysis indicated that the esterase （EST） activities in JN population were higher than those in BD and BDG populations. They showed that when α-NA, α-NB, and α-NA were used as substrates, females＇ EST activities of JN population were 1.11-, 1.30-, and 1.14-fold and 1.39-, 1.59-, and 1.54-fold higher than those of BD and BDG populations, respectively. When α-NA, α-NB, and β-NA were used as substrates, males＇ EST activities of JN population were 1.13-, 1.12-, and 1,00-fold and 1.20-, 1.14-, and 1.07-fold higher than those of BD and BDG populations, respectively. The results also showed that the specific activities of the females were higher than those of the males in the BD and JN populations, whereas the specific activities of the males were higher than those of the females in the BDG population. The results of bioassay were consistent with those of biochemical analysis. Thus, it was inferred that the elevated ESTs activities might play an important role in conferring the differences of susceptibility of O. chinensis to malathion in the three collected populations. Enzyme kinetic studies indicated that the Km and Vmax values were different among the three collected populations and between the females and the males. The observed changes in the kinetic parameters might be explained by differential expression patterns of isozymes so that th

关键词： Oxya chinensis esterase enzyme kinetics malathion susceptibility

Non-noble metal-based bifunctional electrocatalysts for hydrogen production

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Rare Metals 2022年第7期41卷 2169-2183页

作者： Tong Wu Ming-Zi Sun Bo-Long Huang Department of applied biology and Chemical Technology the Hong Kong Polytechnic UniversityHong Kong 999077China

Hydrogen is a promising candidate for clean and sustainable energy resources to substitute fossil fuels to mitigate global environmental *** hydrogen production has been regarded as a viable and promising *** overall water splitting is currently the predominant electrochemical hydrogen production method,which could be driven by renewable energy to achieve sustainable ***,the current challenges are the intrinsically sluggish and energy-intensive oxygen evolution reduction(OER)at the anode and the expensive noble metal-based catalysts for overall water splitting,which limit the practical *** efforts have been made to develop bifunctional non-noble metal-based electrocatalysts to boost hydrogen production efficiency and lower the ***,alternative oxidation reactions with faster kinetics and less energy requirement than OER are being explored as the anodic reaction to couple with the hydrogen evolution reaction for energy-saving hydrogen *** this review,the non-noble metal-based bifunctional electrocatalysts for overall water splitting,as well as other novel energy-saving hydrogen productions have been introduced and *** challenges and outlooks are commented on at the end of the article.

关键词： Overall water splitting Hydrogen production Bifunctional electrocatalyst Energy-saving hydrogen production Non-noble metal electrocatalysts

Heterologous expression and characterization of two chitinase 5 enzymes from the migratory locust Locusta migratoria

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Insect Science 2016年第3期23卷 406-416页

作者： Ying-Long Li Hui-Fang Song Xue-Yao Zhang Da-Qi Li Ting-Ting Zhang En-Bo Ma Jian-Zhen Zhang Research Institute of applied biology College of Life Science Shanxi University Taiyuan China

Insect chitinases are involved in degradation of chitin from the exoskeleton or peritrophic metrix ofmidgut. In Locusta migratoria, two duplicated Cht5s （LmCht5-1 and LmCht5-2） have been shown to have distinct molecular characteristics and biological roles. To explore the protein properties of the two LmCht5s, we heterologously expressed both enzymes using baculovirus expression system in SF9 cells, and characterized kinetic and carbohydrate-binding properties of purified enzymes. LmCht5-1 and LmCht5-2 exhibited similar pH and temperature optimums. LmCht5-1 has lower Km value for the oligomeric substrate （4MU-（GlcNAe）3）, and higher Km value for the longer substrate （CM-Chitin- RBV） compared with LmCht5-2. A comparison of amino acids and homology modeling of catalytic domain presented similar TIM barrel structures and differentiated amino acids between two proteins. LmCht5-1 has a chitin-binding domain （CBD） tightly bound to colloidal chitin, but LmCht5-2 does not have a CBD for binding to colloidal chitin. Our results suggested both LmCht5- I and LmCht5-2, which have the critical glutamate residue in region II of catalytic domain, exhibited chitinolytic activity cleaving both polymeric and oligomeric substrates. LmCht5-1 had relatively higher activity against the oligomeric substrate, 4MU-（GlcNAc）3, whereas LmCht5-2 exhibited higher activity toward the longer substrate, CM-Chitin-RBE These findings are helpful for further research to clarit}g their different roles in insect growth and development.

关键词： chitinase 5 enzyme kinetics heterologous expression Locusta migratoria

Transformation of leather waste into microwave-activated and N-doped carbon for Li-S batteries

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新型炭材料(中英文) 2025年

作者： Carolina Pano-Azucena Roberto Rosas-Rangel Miguel Olvera-Sosa David Salvador González-González Rene Rangel-Mendez Luis Felipe Chazaro-Ruiz Miguel Avalos-Borja Javier Antonio Arcibar-Orozco CIATEC.Center for applied Innovation in Competitive Technologies Tecnologico de Monterrey School of Engineering and Sciences Instituto Potosino de Investigación Científica y Tecnológica Universidad Autónoma de Coahuila Facultad de SistemasCiudad Universitaria

The use of carbon from waste biomass has the potential to buffer the drawbacks of Li-S batteries and improve their overall performance. Chrome-Tanned-LeatherShavings(CTLS) are undesirable wastes, highly available for transformation into porous carbon. Microwave activation is an efficient state-of-the-art procedure to obtain unique porous structures and nitrogen incorporation can improve the performance of porous carbons. This study proposes the transformation of CTLS into a microwave activated porous carbon, and then was modified to introduce nitrogen. A microporous activated carbon with a specific surface area of 556 m2g-1 with honeycomb-like structure was obtained. Both urea thermal decomposition and ethanolamine impregnation improves the nitrogen and amine presence of surface groups. However,the results indicated that only urea treatment was effective in improving the initial capacity of the cell(1363 mAhg-1), which is probably linked with the sorption of long-chain polysulfides. This investigation confirms that it is possible to obtain carbon materials from CTLS, for use as sulfur-host cathodes in Li-S batteries, and improve their performance with urea thermal decomposition. Furthermore, a Radial basis function neural network was fitted to provide statistical support to the experimental results. The trained model corroborated the importance of nitrogen content of the carbons in the discharge capacity of the cells.

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