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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

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Recent Advancements in the Optimization Capacity Configuration and Coordination Operation Strategy of Wind-Solar Hybrid Storage System

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Energy Engineering 2025年第1期122卷 285-306页

作者： Hongliang Hao Caifeng wen Feifei Xue HaoQiu Ning Yang Yuwen Zhang Chaoyu Wang Edwin E.Nyakilla Department of New Energy Storage Peking University Ordos Research Institute of EnergyOrdos017010China School of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot010080China key Laboratory of Wind Energy and Solar Energy Utilization Technology Inner Mongolia University of TechnologyHohhot010051China

Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy *** paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,***/Simulink was used for simulation *** optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 ***,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations *** proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.

关键词： Electric-thermal hybrid storage modal decomposition multi-objective genetic algorithm capacity optimization allocation operation strategy

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Thermoresponsive helical dendronized poly(arylacetylene)s:modulating the dynamic chirality

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Science China Chemistry 2025年

作者： Xueting Lu Lei Wang Liangxuan Ren wen Li Afang Zhang International Joint Laboratory of Biomimetic&Smart Polymers School of Materials Science and EngineeringShanghai University

Helical poly(arylacetylene)s have formed an intriguing class of polymers,whose chiralities are dynamic and liable to external *** combining dendronized polymer topology with dendritic oligoethylene glycols (OEGs),we here report on synthesis of a homologous series of thermoresponsive dendronized poly(arylacetylene)s with either poly(phenyl acetylene) or poly(naphthalene acetylene) as the backbones,and investigate tunability of their helical *** polymers carry dendritic OEG pendants with either methoxyl-or ethoxyl-terminals to tune their unprecedent thermoresponsive behaviors,and at the same time,dendritic shielding plays an important role in mediating their thermal phase transition *** of these polymers is originated from the chiral alanine or phenylalanine moieties within the dendritic pendants,which can be tailored through manipulating solvation in different organic solvents or via thermal dehydration and collapse in ***,achiral additives such as linear or dendritic OEGs and benzene derivatives can act similarly as thermal dehydration to induce chirality transitions of these polymers in aqueous phase through interplay competitions between the additives and the polymers against their hydration.

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The potential mechanism and clinical application value of remote ischemic conditioning in stroke

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Neural Regeneration Research 2025年第6期20卷 1613-1627页

作者： Yajun Zhu Xiaoguo Li Xingwei Lei Liuyang Tang Daochen wen Bo Zeng Xiaofeng Zhang Zichao Huang Zongduo Guo The First Affiliated Hospital of Chongqing Medical University ChongqingChina

Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved.

关键词： Akt apoptosis autophagy cerebral perfusion cerebral vascular stenosis clinical transformation hemorrhagic stroke ischemic stroke neuroinflammation neuroprotection Notch1 PI3K remote ischemic conditioning stroke

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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats

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Neural Regeneration Research 2025年第4期20卷 1164-1177页

作者： Pengfei Wang Yuewei Bi Min Li Jiazhi Chen Zhuyong Wang Huantao wen Ming Zhou Minjie Luo Wangming Zhang Neurosurgery Center Department of Pediatric NeurosurgeryGuangdong Provincial Key Laboratory on Brain Function Repair and RegenerationZhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

Long-term levodopa administration can lead to the development of levodopa-induced *** oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced ***,studies have reported increased oscillation power in cases of levodopa-induced ***,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced ***,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is *** found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s ***,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma *** of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum ***,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum *** findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia.

关键词： aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials neuromodulation Parkinson’s disease primary motor cortex

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Weight Choosability of Graphs with Maximum Degree 4

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Acta Mathematica Sinica,English Series 2020年第6期36卷 723-732页

作者： You LU Chong LI Zheng ke miao School of Mathematics and Statistics and Xi'an-Budapest Joint Research Center for Combinatorics Northwestern Polytechnical UniversityXi'an710129P.R.China Department of Mathematics West Virginia UniversityMorgantownWV 26506USA Research Institute of Mathematical Science and School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou221116P.R.China

Let k be a positive integer.A graph G is k-weight choosable if,for any assignment L(e)of k real numbers to each e∈E(G),there is a mapping f:E(G)→R such that f(uv)∈L(uv)and∑e∈∂(u)^f(e)≠∑e∈∂(u)^f(e)for each uv∈E(G),where?(v)is the set of edges incident with *** a strengthening of the famous 1-2-3-conjecture,Bartnicki,Grytczuk and Niwcyk[Weight choosability of *** Theory,60,242–256(2009)]conjecture that every graph without isolated edge is 3-weight *** conjecture is wildly open and it is even unknown whether there is a constant k such that every graph without isolated edge is k-weight *** this paper,we show that every connected graph of maximum degree 4 is 4-weight choosable.

关键词： 1-2-3 conjecture weighting weight choosability Combinatorial Nullstellensatz

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Integrating lipidomics and gut microbiota to study the anti-hyperlipidemia effect of Sargentodoxae Caulis extract

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Traditional Medicine Research 2025年第1期10卷 1-11页

作者： Xiao-Xiao Zhang Li Jia Xiu-Jun Zhan Charity Ngina Qing-Rui Zhang Xiao-Ge Li Qi-Bao Jiang Shi Bai miao-miao Jiang National key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjin 301617China Haihe Laboratory of Modern Chinese Medicine Tianjin 301617China School of Medicine Taizhou UniversityTaizhou 318000China.

Background:Sargentodoxae Caulis(SC)is the vine stem of Sargentodoxa Cuneata(Oliv.)Rehd.&*** in ***,and it in traditional Chinese medicine has been known for promoting blood circulation and removing blood stasis as recorded in the ancient book“Illustrated Classics of Materia Medica”.It has been used effectively to treat blood stasis too in modern clinical ***,the anti-hyperlipidemia effect of SC is not fully *** paper aims at exploring the use of SC stems to improve the balance of blood lipids in the body,and its new role in treating ***:The effects of SC extract on hyperlipidemia were explored by combining lipidomics and gut ***,we explored the potential mechanism of SC in treating hyperlipidemia by pathway ***:The results showed that the stem extract of SC could restore the physiological and biochemical indices of hyperlipidemia in mice,as well as repair the morphological and structural damage to *** to the Model group,the SC extract significantly reduced the liver index,epididymal fat index,and Lee’s *** also significantly decreased serum levels of total cholesterol,triglycerides,low-density lipoprotein cholesterol,peroxisome proliferator-activated receptor gamma(PPAR-γ),D-lactate,and free fatty acids,while significantly increasing the relative content of peroxisome proliferator-activated receptor alpha(PPAR-α).These changes were statistically ***-targeted lipidomics,based on LC-MS,were utilized to investigate the lipid metabolism characteristics in serum,liver,and epididymal fat of the *** was observed that,compared to the blank group,the Model group exhibited significant changes primarily in glycerol lipids and *** treatment group also displayed alterations in these lipids.A total of 38,81,and 27 differential lipids were identified in serum,liver,and epididymal fat samples,*** these,14 common differenti

关键词： hyperlipidemia Sargentodoxae Caulis lipidomics intestinal flora

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NASTCNN: a spatio-temporal convolutional neural network with non-local attention mechanism for image-induced brain activity pattern recognition

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Optoelectronics Letters 2025年

作者： TAN Xiangxin SHAO Mingxiong ZENG ke GU Yue School of Computer Science and Engineering， Tianjin University of Technology Engineering Research Center of Learning-Based Intelligent System (Ministry of Education)， Tianjin University of Technology Krembil Research Institute， University Health Network

Deciphering the brain’s visual processing mechanisms has always been a hot topic. Using neural signal patterns to predict the corresponding external visual stimuli is crucial in understanding the interaction of real visual scenes. There are some challenges in the study of image-induced brain activity pattern recognition based on electroencephalogram (EEG)， e.g. how to fully utilize the effective features of EEG signals to improve the classification， and how the frequency and the length of EEG effect the model performance. We design an experimental paradigm that minimizes the interaction between visual stimuli， and propose a spatio-temporal convolutional neural network with non-local attention mechanism (NASTCNN) for image-induced brain activity pattern recognition. The framework utilizes non-local feature extraction operations to realize global information interaction between EEG signals over long distances and enhance the feature expression of some important information. Our model achieves the best performance on both MNIST-EEG and ImageNet-EEG datasets. The classification results are 24.00% and 50.10% respectively， higher than the random probability. We also analyze the effects of different EEG frequency bands and time subsequences of different lengths on the classification performance and which brain regions are activated over time. The results show that when full frequency band and entire length sequence are selected， the classification result is optimal. The occipital region is essential for processing visual tasks， and the temporal region and some frontal regions also play important role in the later stage of visual decoding. This research can help us better understand the visual processing mechanism of the brain.

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3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei Chen Nian Liu Jing He Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie Yong He State key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

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Study on pyrolysis and gasification of wood in MSW

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Journal of Environmental Sciences 2006年第2期18卷 407-415页

作者： NI Ming-jiang XIAO Gang CHI Yong YAN Jian-hua miao Qi ZHU wen-li CEN ke-fa Institute for Thermal Power Engineering State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

In order to develop municipal solid waste（MSW） pyrolysis/gasification and melting technology with low emission and high efficiency, it was planed that all the main components in MSW and some typical kinds of MSW were pyrolyzed/gasified to propose an expert system for raw MSW. In this paper, wood, which was a prevalent component in MSW, was pyrolyzed and gasified in fluidized-bed reactors at different apparent excess air ratios （EARs）, temperatures and fluidizing velocities. For pyrolysis, with tem- perature increasing from 400℃ to 700℃, the yield of pyrolysis char decreased while that of pyrolysis gas increased （in this paper respectively from 28% to 20% and from 10% to 35%）, and when temperature was 500℃, the yield of pyrolysis tar reached the highest, up to 38% in this paper. It was the optimum for gasification when temperature was 600℃ and apparent EAR was 0.4. Under the experimental conditions of this paper, gasification efficiency achieved 73%, lower heat value（LHV） reached 5800 kJ/（Nm^3） and yield of syngas was 2.01 Nm^3/kg. Lower fluidizing velocity was useful to upgrade gasification efficiency and LHV of syngas for wood gasification. Based on the results, the reactive courses and mechanism were analyzed respectively for wood pyrolysis and gasification.

关键词： wood pyrolysis gasification municipal solid waste(MSW)

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