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Griseofulvin enantiomers and bromine-containing griseofulvin derivatives with antifungal activity produced by the mangrove endophytic fungus Nigrospora sp.QQYB1

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Marine Life Science & Technology 2024年第1期6卷 102-114页

作者： Ge Zou Wencong Yang Tao Chen Zhaoming Liu Yan Chen Taobo Li Gulab Said Bing Sun Bo Wang Zhigang She School of Chemistry Sun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Applied Microbiology Southern China Guangdong Provincial Key Laboratory of Microbial Culture Collection and ApplicationInstitute of MicrobiologyGuangdong Academy of SciencesGuangzhou 510070China School of Pharmacy Anhui Medical UniversityHefei 230032China Department of Chemistry Women University SwabiSwabi 23430Pakistan

Marine microorganisms have long been recognized as potential sources for drug discovery.Griseofulvin was one of the first antifungal natural products and has been used as an antifungal agent for decades.In this study,12 new griseofulvin derivatives[(±)-1-2,(+)-3,(±)-4,10-12,and 14-15]and two new griseofulvin natural products(9 and 16)together with six known analogues[(-)-3,5-8,and 13]were isolated from the mangrove-derived fungus Nigrospora sp.QQYB1 treated with 0.3%NaCl or 2%NaBr in rice solid medium.Their 2D structures and absolute configurations were established by extensive spectroscopic analysis(1D and 2D NMR,HRESIMS),ECD spectra,computational calculation,DP4+analysis,and X-ray single-crystal diffraction.Compounds 1-4 represent the first griseofulvin enantiomers with four absolute configurations(2S,6'S;2R,6'R;2S,6'R;2R,6'S),and compounds 9-12 represent the first successful production of brominated griseofulvin derivatives from fungi via the addition of NaBr to the culture medium.In the antifungal assays,compounds 6 and 9 demonstrated significant inhibitory activities against the fungi Colletotrichum truncatum,Microsporum gypseum,and Trichophyton mentagrophyte with inhibition zones varying between 28 and 41 mm(10μg/disc).The structure-activity relationship(SAR)was analyzed,which showed that substituents at C-6,C-7,C-6'and the positions of the carbonyl and double bond of griseofulvin derivatives significantly affected the antifungal activity.

关键词： Mangrove endophytic fungus Nigrospora sp. Griseofulvin Antifungal activity

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Efficient and rapid conversion of human astrocytes and ALS mouse model spinal cord astrocytes into motor neuron-like cells by defined small molecules

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Military Medical Research 2021年第1期8卷 62-78页

作者： An-Dong Zhao Hua Qin Meng-Li sun Kui Ma Xiao-bing Fu Tianjin Medical University Tianjin 300070China Research Center for Tissue Repair and Regeneration Affiliated to the Medical Innovation Research Division and 4th Medical Center PLA General Hospital and PLA Medical College28 Fu Xing RoadHaidian DistrictBeijing 100853China PLA Key Laboratory of Tissue Repair and Regenerative Medicine and Beijing Key Research Laboratory of Skin Injury Repair and RegenerationBeijing 100048China Research Unit of Trauma Care Tissue Repair and RegenerationChinese Academy of Medical SciencesBeijing 100048China

Background: Motor neuron degeneration or loss in the spinal cord is the characteristic phenotype of motor neuron diseases or spinal cord injuries. Being proliferative and located near neurons, astrocytes are considered ideal cell sources for regenerating neurons.Methods: We selected and tested different combinations of the small molecules for inducing the conversion of human and mouse astrocytes into neurons. Microscopic imaging and immunocytochemistry analyses were used to characterize the morphology and phenotype of the induced neurons while RT-q PCR was utilized to analyze changes in gene expression. In addition, whole-cell patch-clamp recordings were measured to examine the electrophysiological properties of induced neurons.Results: The results showed that human astrocytes could be rapidly and efficiently converted into motor neuronlike cells by treatment with defined small molecules, with a yield of over 85% motor neuron-like cells attained. The induced motor neuron-like cells expressed the pan-neuronal markers TUJ1, MAP2, Neu N, and Synapsin 1 and motor neuron markers HB9, ISL1, CHAT, and VACh T. During the conversion process, the cells did not pass through a proliferative neural progenitor cell intermediate. The induced motor neurons were functional, showing the electrophysiological properties of neurons. The same chemical cocktail could induce spinal cord astrocytes from an amyotrophic lateral sclerosis mouse model carrying a SOD1 mutation to become motor neuron-like cells that exhibited a decrease in cell survival and an increase in oxidative stress compared to that observed in wild-type MNs derived from healthy mice. Moreover, the chemical induction reduced oxidative stress in the mutant astrocytes.Conclusions: The results of the present study demonstrated the feasibility of chemically converting human and mouse astrocytes into motor neuron-like cells that are useful for neurodegenerative disease modeling and regenerative medicine.

关键词： Human astrocyte Motor neuron Reprogramming Transdifferentiation Conversion Regeneration Amyotrophic lateral sclerosis Neurodegenerative

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Changes in ecological stoichiometry and nutrient resorption in Castanopsis hystrix plantations along an urbanization gradient in the lower subtropics

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Journal of Forestry Research 2021年第6期32卷 2323-2331页

作者： Feifan Li Bing Sun Zhaowan Shi Nancai Pei Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou510520People’s Republic of China

The stoichiometry of carbon,nitrogen and phosphorous in plants can reflect the interactions between plants and their environment.The interplay between plant nutrients,climatic factors,and soil properties and the underlying regulatory mechanisms are pillars of ecology but remain underexplored.In this study of plant C-N-P stoichiometry and nutrient resorption in Castanopsis hystrix groves in three cities(Guangzhou,Zhongshan,and Lechang)that represent an urban-rural gradient in Guangdong Province,South China,we explored potential relationships among NO_(2) concentrations,diameter at breast height(DBH),and resident human population.Mean annual temperature,mean annual precipitation,insolation duration per year,and the human resident population differed significantly among the three cities.Soil C-N-P was always highest in suburban Lechang,and the concentration of NO_(2) was highest in urban Guanghzou(55.33±0.67μg m^(-3))and positively correlated with the resident population and leaf N:P.Our findings suggest that C-N-P stoichiometry of C.hystrix was better explained by NO_(2)than by soil C-N-P stoichiometry and that nutrient resorption was better explained by leaf nutrients and DBH than by NO_(2) and soil stoichiometry.Our study supports the hypothesis that rapid urbanization influences NO_(2) concentrations and microclimate,which may jointly change the stoichiometry of plant nutrients in the forest ecosystems.

关键词： Ecological stoichiometry Nutrient cycling Plant-environment interaction Subtropical forest Urban–rural gradient

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Vaginal Delivery in a Primipara with Glanzmann Thrombasthenia

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Maternal-Fetal Medicine 2023年第3期5卷 192-194页

作者： Fangcan sun Jiahui Wang Youguo Chen Jie Yin bing Han Department of Obstetrics and Gynecology The First Affiliated Hospital of Soochow UniversitySuzhou 215006China Department of Hematology The First Affiliated Hospital of Soochow UniversitySuzhou 215006China

To editor:Glanzmann thrombasthenia(GT)is a rare autosomal recessive bleeding disorder that is characterized by a quantitative and/or qualitative defect in the platelet integrinαIIbβ3(previously known as glycoprotein(GP)IIb/IIIa),the major platelet receptor of fibrinogen.DefectiveαIIbβ3 can result in the absence of platelet aggregation.Pregnancy and delivery in women with GT can present specific challenges as there is a significant risk of both maternal and fetal bleeding.

关键词： Obstetrical forceps Glanzmann thrombasthenia Multidisciplinary management Pregnancy rFVIIa Vaginal delivery

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Study of experiment method for triaxial frost heaving constitutive relation of frozen soil

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Research in Cold and Arid Regions 2010年第3期2卷 230-234页

作者： Bing Sun China Railway First Survey and Design Institute Group Xi'an Shaanxi 710043 China

A new experiment method is introduced to study the relations between frost heaving strain and stress of soil or fracture rock under different moisture contents, temperatures and stress states. Based on experiments, a new triaxial frost heaving stress-strain relation is presented aiming at tunnel in cold regions. The experimental equipments are strain-controlled and low temperature buildup, and different restrained conditions are controlled by changing the stiffness of a test-force-ring. Then the frost heaving strain and stress of soil or fracture rock can be obtained under different restrained conditions, and the frost heaving stress-strain relation can be got by regression analysis of some feature points. Experiments of saturated sandy soil conducted by this method show that the triaxial frost heaving stress-strain relation could be expressed by loga- rithmic curves, and the frost heaving stress changes linearly with the logarithm of the frost heaving strain. The stronger the constraint, the smaller the frost heaving strain and the larger the frost heaving stresses. The frost heaving stresses would tend to a limit value with increasing the constraint intensity. The larger the confining pressure, the larger the frost heaving strain and stress.

关键词： triaxial frost heaving stress-strain relation frost heaving stress tunnel in cold region fracture rocks

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SNWPM:A Siamese Network Based Wireless Positioning Model Resilient to Partial Base Stations Unavailable

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中国通信:英文版 2023年第9期20卷 20-33页

作者： Yasong Zhu Jiabao Wang Yi sun bing Xu Peng Liu Zhisong Pan Wangdong Qi Army Engineering University of PLA Nanjing 210007China Purple Mountain Laboratory Nanjing 210000China

Artificial intelligence(AI)models are promising to improve the accuracy of wireless positioning systems,particularly in indoor environments where unpredictable radio propagation channel is a great challenge.Although great efforts have been made to explore the effectiveness of different AI models,it is still an open problem whether these models,trained with the data collected from all base stations(BSs),could work when some BSs are unavailable.In this paper,we make the first effort to enhance the generalization ability of AI wireless positioning model to adapt to the scenario where only partial BSs work.Particularly,a Siamese Network based Wireless Positioning Model(SNWPM)is proposed to predict the location of mobile user equipment from channel state information(CSI)collected from 5G BSs.Furthermore,a Feature Aware Attention Module(FAAM)is introduced to reinforce the capability of feature extraction from CSI data.Experiments are conducted on the 2022 Wireless Communication AI Competition(WAIC)dataset.The proposed SNWPM achieves decimeter-level positioning accuracy even if the data of partial BSs are unavailable.Compared with other AI models,the proposed SNWPM can reduce the positioning error by nearly 50%to more than 60%while using less parameters and lower computation resources.

关键词： wireless positioning indoor positioning generalization ability AI positioning model attention

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Lactate anions participate in T cell cytokine production and function

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Science China(Life Sciences) 2021年第11期64卷 1895-1905页

作者： Jing Wen Shipeng Cheng Yaguang Zhang Ran Wang Jiefang Xu Zhiyang Ling Liyan Ma Xinghao Ai Bing Sun School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Cell Biology CAS Center for Excellence in Molecular Cell ScienceShanghai Institute of Biochemistry and Cell BiologyChinese Academy of SciencesShanghai 200031China School of Life Science University of Science and Technology of ChinaHefei 230026China Shanghai Lung Cancer Center Shanghai Chest HospitalShanghai Jiao Tong UniversityShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China

After antigen stimulation, T cells preferentially increase aerobic glycolysis to meet the bioenergetic and biosynthetic demands of T cell activation, proliferation, and effector functions. Lactate, a by-product of glycolysis, has been reported to function as an important energy source and signaling molecule. Here, we found that lactate anions are involved in cytokine production in Tcells after TCR activation. During ex vivo T cell activation, the addition of excess sodium lactate(Na L) increased the production of cytokines(such as IFNγ/IL-2/TNFα) more than the addition of sodium chloride(NaCl). This enhanced cytokine production was dependent on TCR/CD3 activation but not CD28 activation. In vivo, Na L treatment inhibited tumour growth in subcutaneously transplanted tumour models in a T cell-dependent manner, which was consistent with increased T cell cytokine production in the Na L treatment group compared to the Na Cl treatment group. Furthermore, a mechanistic experiment showed that this enhanced cytokine production was regulated by GAPDH-mediated post-transcriptional regulation. Taken together, our findings indicate a new regulatory mechanism involved in glycolysis that promotes T cell function.

关键词： lactate glycolysis TCR activation immunometabolism

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Fabrication of azobenzene-functionalized porous polymers for selective CO_(2) capture

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Chinese Journal of Chemical Engineering 2022年第3期35卷 24-30页

作者： Ding-Ming Xue Wen-Juan Zhang Xiao-Qin Liu Shi-Chao Qi Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

Many solid adsorbents have been prepared for the CO_(2)capture.In particular,the photoresponsive adsorbents have attracted extensive interests because of their tunable pore structure and variable responsive behaviors provoked by the external light.However,it is challenging to fabricate the photoresponsive adsorbents featured the big CO_(2)capacity and high CO_(2)selectivity.Herein,copolymerized between 4-phenylazobenzoyl chloride,2,4,6-trichloro-1,3,5-triazine and melamine,a series of azobenzenefunctionalized porous polymers(PTM-AZOs)are successfully synthesized.The PTM-AZOs are verified in possession of proper pore structures,large surface area and photoconductive properties through a series of characterization.The PTM-AZO-2 with the trans-isomerization exhibits the best CO_(2)adsorption amount of 2.7 mmol·g^(-1)(273 K and 0.1 MPa),while the CO_(2)/N_(2)selectivity can reach 2459 and 607 on the trans-and cis-isomerization,respectively.The regulatable pore structures controlled by the photoresponsive azobenzene groups affect the CO_(2)capture performance of the PTM-AZOs.

关键词： Adsorption CO_(2)capture Selectivity Azobenzene Photoresponse

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A multi-AUVs Cooperative Hunting Algorithm for Environment with Ocean Current

A multi-AUVs Cooperative Hunting Algorithm for Environment w...

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第37届中国控制会议

作者： Qingqin Liu Bing Sun Daqi Zhu Laboratory of Underwater Vehicles and Intelligent Systems Shanghai Maritime University

Multi-AUV cooperative hunting is a very challenging research area,a novel multi-AUVs bio-inspired cooperative hunting algorithm is presented.Firstly,a bio-inspired Neural Network model（BINN） is established to represent the AUV underwater working environment.Each point in the grid map corresponds to the activity of a neural activity in the BINN,and the next target point of the hunting AUV can be planned autonomously according to the neuron activity of the neurons in the BINN.Secondly,the direction decision algorithm is embedded into the BINN hunting model for the ocean current environment,and the four hunting AUVs all move from the left side of the map,with the rhombic formation to hunt the evader AUV.And the integrated algorithm proposed is compared with the hunting method without direction decision.Finally,simulation results are presented to demonstrate that the proposed algorithm is effective for cooperative hunting mission.

关键词： Autonomous underwater vehicle cooperative hunting direction decision algorithm bio-inspired neural network

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Trajectory Re-planning and Tracking Control of Unmanned Underwater Vehicles on Dynamic Model

Trajectory Re-planning and Tracking Control of Unmanned Unde...

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第30届中国控制与决策会议

作者： Caicha Cui Daqi Zhu Bing Sun Laboratory of Underwater Vehicles and Intelligent Systems Shanghai Maritime University

The trajectory tracking control In UUV’s control system is an important research topic. Its kinematic model can help people understand the motion, while it is the thrusters that makes UUV move. Based on the dynamic model, this paper study about the tracking control problem of UUV. A trajectory re-planning controller based on model predictive control(MPC) is designed and added in the trajectory tracking control layer to form a new control system to produce a re-planned trajectory with obstacle avoidance. Firstly, an obstacle avoidance function is used for the design of MPC trajectory re-planning controller. Then, the tracking control law is obtained by the MPC model with speed and thrust constraints and the sequential quadratic programming optimization algorithm. Lastly, compared to the backstepping tracking algorithm, the speed jump of backstepping is sharp, while the MPC tracking controller can solve the speed jump problem well, and the MPC controller has a lower requirement for the thrust. Simulation results of different obstacles demonstrate its efficiency of the proposed the MPC trajectory re-planning tracking control algorithm for UUV.

关键词： Unmanned Underwater Vehicles Dynamic Model Model Predictive Control Trajectory Re-planning Trajectory Tracking

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