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Nickel-catalyzed carbonylative four-component 1,4-dicarbofunctionalization of 1,3-enynes

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Science China Chemistry 2024年第6期67卷 2029-2038页

作者： Yan Zhao Qi-Chao Shan Hong Xin Pin Gao Xu Yang Xin-Hua Duan li-na guo Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Material Chemistry and Engineering Research Center of Energy StorageMaterials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China

An efficient Ni-catalyzed four-component 1,4-carbocarbonylation of 1,3-enynes with activated alkyl halides and arylboronic acids under atmospheric pressure of CO is presented.By tuning the electronic and steric effects of alkyl radicals,both electronrich and electron-deficient 1,3-enynes were compatible with this cascade.This protocol features mild conditions,broad substrate scope,excellent functional group compatibility and facile gram-scale synthesis,providing a practical approach to the quaternary carbon center-containing allenyl ketones.Mechanistic study revealed that the acyl-NiIIspecies plays an important role in both the coupling and the alkyl radical generation processes.

关键词： Ni catalysis four-component 1 4-carbocarbonylation 1 3-enynes

Photoinduced copper-catalyzed alkoxyl radical-triggered ring-expansion/aminocarbonylation cascade

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Chinese Chemical Letters 2024年第6期35卷 331-336页

作者： Jing-Qi Tao Shuai liu Tian-Yu Zhang Hong Xin Xu Yang Xin-Hua Duan li-na guo Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Material Chemistry and Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an 710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China

A photoinduced copper-catalyzed alkoxyl triggered C-C bond cleavage/aminocarbonylation cascade is presented.Through adjusting the structure of alkoxyl radical precursors,functionalized lactones and ketoamides were synthesized with good yields and excellent functional group tolerance under redox-neutral conditions.Notably,this protocol enables the integration of lactone fragments with many amine drugs and drug fragments.

关键词： Copper catalysis Ring-expansion Aminocarbonylatioin Macrolactones Keto-amides

Harnessing bacteria for tumor therapy:Current advances and challenges

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Chinese Chemical Letters 2024年第2期35卷 97-106页

作者： lina guo Jinsong Ding Wenhu Zhou Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China Changsha Medical University Academician WorkstationChangsha 410219China Key Laboratory of Biological nanotechnology of national Health Commission Changsha 410008China

After a century of standstill,bacteria-based tumor therapy has resurged recently benefiting from the revolution of tumor immunotherapy,which provides unique solutions to tackle the obstacles of traditional tumor treatments.Obligate and facultative anaerobes with active tropism can selectively colonize at tumor sites and suppress tumor growth via different mechanisms,serving as attractive tools for tumor treatment either as a monotherapy or combining with other therapies for synergistic anti-tumor effects.In this critical review,we introduce the recent advances of bacteria-based tumor therapy from the following aspects.First,the general properties of bacteria are reviewed emphasizing on their structural components related to tumor immunotherapy,and the main bacteria that have been used in tumor therapy are listed.Then,the benefits of bacteria for tumor therapy are illustrated,such as tumor targetability,deep penetration,and facile genetic engineering for attenuation,enhanced efficacy,as well as bioimaging.Next,anti-tumor mechanisms of bacteria are summarized,which refer to intrinsic tumoricidal activities,immune activation,bacteria metabolism,and their capability to regulate gut microbiota homeostasis.Moreover,bacteria could act as carriers to deliver various types of therapeutics to achieve combination therapy with improved efficacy.In addition,several challenges for anti-tumor applications of bacteria are discussed regarding the delivery,efficacy and safety issues,and potential solutions are also provided.Finally,the possible improvements and perspectives are discussed in the end,which provide a guideline for the design of advanced bacteria-based tumor therapeutics in the future.

关键词： Bacteria Tumor targeting Immunotherapy Combination therapy Genetic engineering Surface decoration

An improved deep dilated convolutional neural network for seismic facies interpretation

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Petroleum Science 2024年第3期21卷 1569-1583页

作者： na-Xia Yang guo-Fa li Ting-Hui li Dong-Feng Zhao Wei-Wei Gu State Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical Exploration China University of Petroleum (Beijing) Dagang Branch Research InstituteBGP

With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural networks. These intelligent and automated methods significantly reduce manual labor, particularly in the laborious task of manually labeling seismic facies. However, the extensive demand for training data imposes limitations on their wider application. To overcome this challenge, we adopt the UNet architecture as the foundational network structure for seismic facies classification, which has demonstrated effective segmentation results even with small-sample training data. Additionally, we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader range. The seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies boundaries. Comparative analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results, as evidenced by various evaluation metrics for image segmentation. Obviously, the classification accuracy reaches an impressive 96%. Furthermore, the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method, which accurately defines the range of different seismic facies. This approach holds significant potential for analyzing geological patterns and extracting valuable depositional information.

关键词： Seismic facies interpretation Dilated convolution Spatial pyramid pooling Internal feature maps Compound loss function

light People:Prof.Eric Mazur speaks about ultrafast optics and education

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light(Science & Applications) 2024年第3期13卷 402-406页

作者： Chenzi guo Yang li Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina State Key Laboratory of Precision Measurement Technology and Instrument Department of Precision InstrumentTsinghua UniversityBeijingChina

Prof.Eric Mazur is a great influencer over and beyond the optics community.As a physicist,he is a pioneer of ultrafast optics and was one of the inventors of colliding-pulse mode-locked laser.As an educator,he not only gave talks to thousands,but also revolutionized teaching with his globally renowned methodology“Peer Instruction”.As a leader and entrepreneur,he co-founded several companies and was President of Optica(formerly the Optical Society)and currently is the Chair of the Optica Foundation.Here,light:Science&Applications talked with Prof.Eric Mazur about his opinions on research,education and industry.The full interview video can be found in the Supplementary File.

关键词： optics education companies

Predictive model for non-malignant portal vein thrombosis associated with cirrhosis based on inflammatory biomarkers

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1213-1226页

作者： guo-Le Nie Jun Yan Ying li Hong-Long Zhang Dan-na Xie Xing-Wang Zhu Xun li The First School of Clinical Medicine Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of General Surgery The First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BACKGROUND Portal vein thrombosis(PVT),a complication of liver cirrhosis,is a major public health concern.PVT prediction is the most effective method for PVT diagnosis and treatment.AIM To develop and validate a nomogram and network calculator based on clinical indicators to predict PVT in patients with cirrhosis.METHODS Patients with cirrhosis hospitalized between January 2016 and December 2021 at the First Hospital of Lanzhou University were screened and 643 patients with cirrhosis who met the eligibility criteria were retrieved.Following a 1:1 propensity score matching 572 patients with cirrhosis were screened,and relevant clinical data were collected.PVT risk factors were identified using the least absolute shrinkage and selection operator(LASSO)and multivariate logistic regression analysis.Variance inflation factors and correlation matrix plots were used to analyze multicollinearity among the variables.A nomogram was constructed to predict the probability of PVT based on independent risk factors for PVT,and its predictive performance was verified using a receiver operating characteristic curve(ROC),calibration curves,and decision curve analysis(DCA).Finally,a network calculator was constructed based on the nomograms.RESULTS This study enrolled 286 cirrhosis patients with PVT and 286 without PVT.LASSO analysis revealed 13 variables as strongly associated with PVT occurrence.Multivariate logistic regression analysis revealed nine indicators as independent PVT risk factors,including etiology,ascites,gastroesophageal varices,platelet count,D-dimer,portal vein diameter,portal vein velocity,aspartate transaminase to neutrophil ratio index,and platelet-to-lymphocyte ratio.LASSO and correlation matrix plot results revealed no significant multicollinearity or correlation among the variables.A nomogram was constructed based on the screened independent risk factors.The nomogram had excellent predictive performance,with an area under the ROC curve of 0.821 and 0.829 in the training and testing groups,respectively.Calibr

关键词： Portal vein thrombosis liver cirrhosis Nomogram Inflammatory markers Aspartate aminotransferase to neutrophil ratio index Platelet-to-lymphocyte ratio

Strategies and prospects for melatonin to alleviate abiotic stress in horticultural plants

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Horticultural Plant Journal 2024年第3期10卷 601-614页

作者： Xiaoyun Wang Meng Cao Hongxin li Ying liu Shuangxi Fan na Zhang Yangdong guo College of Horticulture China Agricultural UniversityBeijing100193China College of Plant Science and Technology Beijing University of AgricultureBeijing102206China Beijing Bei Nong Enterprise Management Co. Ltd.Beijing102206China Sanya Institute of China Agricultural University SanyaHainan572000China

Melatonin is a conserved pleiotropic molecule in animals and plants.Melatonin is involved in many development processes and stress responses;thus,exploring its function in plants,particularly in horticultural plants,has become a rapidly developing field.Many studies have revealed that phytomelatonin acts as a plant biostimulant and increase its tolerance to various abiotic stressors,including extreme temperature,drought,osmotic disturbance,heavy metals,and ultraviolet(UV).Melatonin appears to have roles in the scavenging of reactive oxygen species(ROS)and other free radicals,affecting the primary and secondary metabolism of plants,regulating the transcripts of stress-related enzymes and transcription factors,and crosstalk with other hormones under different environmental conditions.This pleiotropy makes phytomelatonin an attractive regulator to improve resistance to abiotic stress in plants.The recent discovery of the potential phytomelatonin receptor CAND2/PMTR1 and the proposition of putative models related to the phytomelatonin signaling pathways makes phytomelatonin a new plant hormone.Based on relevant studies from our laboratory,this review summarizes the phytomelatonin biosynthetic and metabolic pathways in plants and the latest research progress on phytomelatonin in abiotic stress of horticultural plants.This study will provide a reference for elucidating the regulatory mechanism of phytomelatonin affecting the resistance to abiotic stress in plants.

关键词： Abiotic stress Biostimulant Horticultural plants Phytomelatonin

The infection kinetics and transmission potential of two Guaico Culex viruses in Culex quinquefasciatus mosquitoes

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Virologica Sinica 2024年第2期39卷 228-234页

作者： Ru-Yi Chen Teng Zhao Jing-Jing guo Feng Zhu na-na Zhang Xiao-Feng li Hai-Tao liu Fei Wang Yong-Qiang Deng Cheng-Feng Qin College of Bioscience and Bioengineering Jiangxi Agricultural UniversityNanchang330045China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMSBeijing100071China School of life Sciences Southwest Forestry UniversityKunming650224China

Guaico Culex virus(GCXV)is a newly identified segmented Jingmenvirus from Culex spp.mosquitoes in Central and South America.The genome of GCXV is composed of four or five single-stranded positive Rna segments.However,the infection kinetics and transmission capability of GCXV in mosquitoes remain unknown.In this study,we used reverse genetics to rescue two GCXVs(4S and 5S)that contained four and five Rna segments,respectively,in C6/36 cells.Further in vitro characterization revealed that the two GCXVs exhibited comparable replication kinetics,protein expression and viral titers.Importantly,GCXV Rnas were detected in the bodies,salivary glands,midguts and ovaries of Culex quinquefasciatus at 4–10 days after oral infection.In addition,two GCXVs can colonize Cx.quinquefasciatus eggs,resulting in positive rates of 15%–35%for the second gonotrophic cycle.In conclusion,our results demonstrated that GCXVs with four or five Rna segments can be detected in Cx.quinquefasciatus eggs during the first and second gonotrophic cycles after oral infection.

关键词： Guaico Culex virus(GCXV) Jingmenvirus Culex quinquefasciatus Vertical transmission

Impacts of pancreatic exocrine insufficiency on gut microbiota

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 271-279页

作者： Yulin guo Feng CAO Fei li Department of General Surgery Xuanwu Hospital of Capital Medical UniversityBeijing 100053China Acute Pancreatitis Clinical Center of Capital Medical University Beijing 100053China

Pancreatic exocrine insufficiency(PEI)can be induced by various kinds of diseases,including chronic pancreatitis,acute pancreatitis,and post-pancreatectomy.The main pathogenetic mechanism of PEI involves the decline of trypsin synthesis,disorder of pancreatic fluid flow,and imbalance of secretion feedback.Animal studies have shown that PEI could induce gut bacterial overgrowth and dysbiosis,with the abundance of Lactobacillus and Bifidobacterium increasing the most,which could be partially reversed by pancreatic enzyme replacement therapy.Clinical studies have also confirmed the association between PEI and the dysbiosis of gut microbiota.Pancreatic exocrine secretions and changes in duodenal p H as well as bile salt malabsorption brought about by PEI may affect and shape the abundance and composition of gut microbiota.In turn,the gut microbiota may impact the pancreatic exocrine acinus through potential bidirectional crosstalk.Going forward,more and higher-quality studies are needed that focus on the mechanism underlying the impact of PEI on the gut microbiota.

关键词： Pancreatic exocrine insufficiency Gut microbiota Gut microbiome Pancreatic enzyme replacement therapy