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Virtual Screening and Mechanism of Action of DPP-IV Inhibitory Peptides from Pinctada fucata (P. fucata)

Science and Technology of Food Industry 2021年第16期42卷 1-7页

作者： li j. Su j. Chen M. Dai S. Gao Y. Yin H. The Equipment Public Service Center CAS Key Laboratory of Tropical Marine Bio-resources and Ecology Chinese Academy of Sciences South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China University of Chinese Academy of Sciences Beijing 100049 China Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) Guangzhou 511458 China

In order to discover the dipeptidyl peptidase IV (DPP-IV) peptides quickly from Pinctada fucata (P. fucata), in this research, 20 reported DPP-IV inhibitory peptides in the database were used to form a training set and construct pharmacophore models, which were then valuated by test set molecules and fisher random validation. The online website PeptideCutter was employed to perform the virtual hydrolysis with P. fucata meat protein as raw materials. The optimal pharmacophore model (Hypo1) was used to initially screen the 192 low-molecular peptides (the number of amino acids was no more than 5), which were obtained by the virtual hydrolysis, and then the molecular docking was performed for further screening. Furthermore, the potential DPP-IV inhibitory peptides were synthesized using a solid-phase method, and their activities were verified in vitro and the interaction mechanism was analyzed. The results showed that 4 potential DPP-IV inhibitory peptides, namely LPIY, VQDR, PIY, and APSL were screened through pharmacophore combined with molecule docking. Among them, VQDR and PIY did not show inhibitory activity, while LPIY and APSL had strong DPP-IV inhibitory activity, with IC50 values of 521.19 and 258.67 μmol/L respectively. The interaction mechanism indicated both peptides formed multiple hydrogen bonds with the amino acid residues within the active pocket of DPP-IV, and the proline (P) at the second position of the N-terminal constructed Pi-Alkyl interactions with the residues of the active pocket, which promoted the DPP-IV inhibitory activity for LPIY and APSL. The current work would provide a theoretical method for screening DPP-IV inhibitory peptides derived from P. fucata efficiently. © 2021 Editorial Department of Science and Technology of Food Science. All rights reserved.

关键词： dipeptidyl peptidase IV (DPP-IV) molecular docking peptides pharmacophore model Pinctada fucata (P. fucata)

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Males armed with big weapons win fights at limited cost in ant-mimickingjumping spiders

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Current Zoology 2024年第1期70卷 98-108页

作者： Guocheng Yu Boon Hui Wong Christina j.Painting Hongze li Long Yu Zengtao Zhang Shichang Zhang Daiqin li State Key Laboratory of Biocatalysis and Enzyme Engineering and Centre for Behavioral Ecology and Evolution School of Life SciencesHubei UniversityWuhan430062China Departmentof Biological Sciences National University of Singapore14 Science Drive 4Singapore 117543Singapore Te Aka Matuatua School of Science University of WaikatoPrivate Bag 3105Hamilton 3240New Zealand

A core assumption of sexual selection theory is that sexually selected weapons,specialized morphological structures used directly in male con-tests,can improve an individual's reproductive success but only if the bearer can overcome associated costs,the negative effects on the bear-er's fitness components.However,recent studies have shown that producing and wielding exaggerated weapons may not necessarily be costly.Rather,some traits can be selected for supporting,or compensating for,the expense of producing and wielding such exaggerated weapons.n the ant-mimicking jumping spider Myrmarachne gisti,exaggerated chelicerae are borne only by adult males and not females,showing sexual dimorphism and steep positive allometry with body size.Here,we determine the potential benefits of bearing exaggerated chelicerae during male contests and explore the potential for costs in terms of prey-capture efficiency and compensation between chelicera size and neighboring trait size.While males with longer chelicerae won most of their male-male contests,we found no significant differences in prey-capture effi-ciency between males and females regardless of whether prey was winged or flightless.Males'elongated chelicerae thus do not impede their efficiency at capturing prey.Furthermore,we found that the sizes of all neighboring traits are positively correlated with chelicera size,suggesting that these traits may be under correlational selection.Taken together,our findings suggest that M.gisti males armed with the exaggerated chelicerae that function as weapons win more fights at limited cost for performance in prey capture and compensate for neighboring structures.

关键词： allometry ant-mimic costs elongated chelicerae threat devices trait compensations

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Reply to the note by li Piani et al.

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Defence Technology（防务技术） 2024年第1期31卷 603-606页

作者： T.li Piani j.Weerheijm L.j.Sluys TU Delft Stevinweg 12628 CNDelftthe Netherlands TNO PO Box 452280 AARijswijkthe Netherlands NLDA Faculty of Military Sciences1781 CADen Helderthe Netherlands

In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of adobe.The opportunity for a new model in the field revealed from the observation that two older models recently used by the authors of Ref.[2] shared a linear relationship between the penetration depth P and the impacting velocity v_(O).

关键词： Penetration Adobe Modeling

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GO/MgO/Mg interface mediated strengthening and electromagnetic interference shielding in AZ31 composite

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journal of Magnesium and Alloys 2023年第10期11卷 3800-3814页

作者： Z.Y.Xu C.F.Fang C.j.li R.Wang X.P.Zhang j.Tan Y.M.Wang Key Laboratory of Solidification Control and Digital Preparation Technology(liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China College of Materials Science and Engineering Chongqing UniversityChongqing 400045China Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian 116023China

More requirements of electromagnetic interference(EMI) shielding performance are put forward for lightweight structural materials due to the development of aerospace and 5G communications. Herein, graphene oxide(GO) decorated with SnO_(2) coating is introduced as reinforcement into AZ31 Mg alloy. During the smelting process, the MgO layer is in situ gernerated at interface between GO and the molten Mg alloy matrix by consuming SnO_(2). In the solid state, such kind of interface structure can improve the GO-Mg interface bonding intensity,also significantly generate stacking faults. The AZ31 composite reinfoced by trace modified GO(0.1 wt%) exhibits high ultimate strength and almost the same elongation with AZ31 alloy. Compared with AZ31 alloy, the yield strength and ultimate tensile strength of composite are increased by 33.5% and 23.7%, respectively. Meanwhile, the multi-level electromagnetic reflection from the multi-layer structure of GO and the interface polarization caused by the MgO mid-layer can significantly improve EMI shielding performance. The appropriate interface design strategy achieves the effect of “two birds with one stone”.

关键词： Metal-matrix composites Mechanical properties EMI shielding Microstructures

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A REDUCED ORDER SCHWARZ METHOD FOR NONliNEAR MULTISCALE ELliPTIC EQUATIONS BASED ON TWO-LAYER NEURAL NETWORKS

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journal of Computational Mathematics 2024年第2期42卷 570-596页

作者： Shi Chen Zhiyan Ding Qin li Stephen j.Wright Mathematics Department University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics University of California-BerkeleyBerkeley CA 94720USA Mathematics Department and Discovery Institute University of Wisconsin-Madison MadisonWI 53706USA Computer Sciences Department University of WisconsinMadisonWI 53706USA

Neural networks are powerful tools for approximating high dimensional data that have been used in many contexts,including solution of partial differential equations(PDEs).We describe a solver for multiscale fully nonlinear elliptic equations that makes use of domain decomposition,an accelerated Schwarz framework,and two-layer neural networks to approximate the boundary-to-boundarymap for the subdomains,which is the key step in the Schwarz procedure.Conventionally,the boundary-to-boundary map requires solution of boundary-value elliptic problems on each subdomain.By leveraging the compressibility of multiscale problems,our approach trains the neural network offline to serve as a surrogate for the usual implementation of the boundary-to-boundary map.Our method is applied to a multiscale semilinear elliptic equation and a multiscale p-Laplace equation.In both cases we demonstrate significant improvement in efficiency as well as good accuracy and generalization performance.

关键词： Nonlinear homogenization Multiscale elliptic problem Neural networks Do-main decomposition

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Convexification of Hybrid AC-DC Optimal Power Flow with line-Commutated Converters

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CSEE journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： Hongyuan liang Zhigang li j.H.Zheng Q.H.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

line-commutated converter (LCC)-based high-voltage DC (HVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. Equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

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Paeoniflorin reduces cardiotoxicity of aconitine in H9c2 cells

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中国药理学与毒理学杂志 2019年第9期33卷 689-689页

作者： li j ZHANG SH HE D WANG jF li jQ School of medicine University of Electronic Science and Technology of China&Department of PharmacySichuan Provincial People′s HospitalChengdu 610072China Personalized Drug Therapy Key Laboratory of Sichuan Province&Sichuan Academy of Medical Sciences Chengdu 610072China

OBjECTIVE Aconitine(ACO)as the main active component in Aconitum carmichaelii debeaux(family Ranunlaceae),has highly toxicity in heart and the mechanisms are not clear yet.Paeoniflorin(PF),the main chemical ingredient in Herbaceous peony,can protect heart hurt by antioxidant,vasodilator effect and other effects.In this study,we focused on investigating the mechanism of PF reducing the cardiotoxicity of ACO.METHODS We chose H9c2 cells as experimental subject.MTT,Western blotting and real-time PCR were used to measure cell proliferation,apoptosis,ion channels and oxidative stress.RESULTS Cell proliferation in ACO+PF group was significantly increased compared with ACO group;the ratio with Bcl-2 and Bax and the level of p53 were upregulated by PF,while the level of caspase-3 was lightly reduced.The expression of SCN5A mRNA significantly was increased in ACO+PF group,while the expres⁃sion of RyR2 and Cx43 mRNA was dropped.Compared with ACO group,extracellular LDH and intracellular MDA were highly decreased,while intracellular SOD was regulated.CONCLUSION Cardiotoxicity of ACO in H9c2 cells was signifi⁃cantly decreased by PF.

关键词： acontine paeoniflorin cardiotoxicity H9c2 cell

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Decoupling the role of chemistry and microstructure in hMSCs response to an osteoinductive calcium phosphate ceramic

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Bioactive Materials 2023年第1期19卷 127-138页

作者： V.P.Galván-Chacon D.de Melo Pereira S.Vermeulen H.Yuan j.li P.Habibovic MERLN Institute for Technology Inspired Regenerative Medicine Maastricht Universitythe Netherlands Kuros Biosciences BV 3723 MBBilthoventhe Netherlands

Calcium phosphates(CaP)are widely used synthetic bone graft substitutes,having bioactivity that is regulated by a set of intertwined physico-chemical and structural properties.While some CaPs have shown to be as effective in regenerating large bone defects as autologous bone,there is still the need to understand the role of individual material properties in CaP performance.Here,we aimed to decouple the effects of chemical composition and surface-microstructure of a beta-tricalcium phosphate(TCP)ceramic,with proven osteoinductive potential,on human mesenchymal stromal cells(hMSCs)differentiation.To this end,we replicated the surface structure of the TCP ceramic into polylactic acid without inorganic additives,or containing the chemical constituents of the ceramic,i.e.,a calcium salt,a phosphate salt,or TCP powder.The microstructure of the different materials was characterized by confocal laser profilometry.hMSCs were cultured on the materials,and the expression of a set of osteogenic genes was determined.The cell culture medium was collected and the levels of calcium and phosphate ions were quantified by inductively-coupled plasma mass spectrometry.The results revealed that none of the tested combinations of properties in polymer/composite replicas was as potent in supporting the osteogenic differentiation of hMSCs as the original ceramic.Nevertheless,we observed some effects of the surface structure in the absence of inorganics,as well as combined effects of surface structure and the added salts,in particular calcium,on osteogenic differentiation.The approach presented here can be used to study the role of independent properties in other CaP-based biomaterials.

关键词： Calcium phosphate Microstructure Chemical composition Mesenchymal stromal cells Osteogenic differentiation

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Computed tomography-based radiomics diagnostic approach for differential diagnosis between early-and late-stage pancreatic ductal adenocarcinoma

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World journal of Gastrointestinal Oncology 2024年第4期16卷 1256-1267页

作者： Shuai Ren li-Chao Qian Ying-Ying Cao Marcus j Daniels li-Na Song Ying Tian Zhong-Qiu Wang Department of Radiology Jiangsu Province Hospital of Chinese MedicineAffiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Geratology Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing 210022Jiangsu ProvinceChina Department of Radiology NYU Langone HealthNew YorkNY 10016United States

BACKGROUND One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma(PDAC)is that most patients are usually diagnosed at late stages.There is an urgent unmet clinical need to identify and develop diagnostic methods that could precisely detect PDAC at its earliest stages.METHODS A total of 71 patients with pathologically proved PDAC based on surgical resection who underwent contrast-enhanced computed tomography(CT)within 30 d prior to surgery were included in the study.Tumor staging was performed in accordance with the 8th edition of the American joint Committee on Cancer staging system.Radiomics features were extracted from the region of interest(ROI)for each patient using Analysis Kit software.The most important and predictive radiomics features were selected using Mann-Whitney U test,univar-iate logistic regression analysis,and minimum redundancy maximum relevance(MRMR)method.Random forest(RF)method was used to construct the radiomics model,and 10-times leave group out cross-validation(LGOCV)method was used to validate the robustness and reproducibility of the model.RESULTS A total of 792 radiomics features(396 from late arterial phase and 396 from portal venous phase)were extracted from the ROI for each patient using Analysis Kit software.Nine most important and predictive features were selected using Mann-Whitney U test,univariate logistic regression analysis,and MRMR method.RF method was used to construct the radiomics model with the nine most predictive radiomics features,which showed a high discriminative ability with 97.7%accuracy,97.6%sensitivity,97.8%specificity,98.4%positive predictive value,and 96.8%negative predictive value.The radiomics model was proved to be robust and reproducible using 10-times LGOCV method with an average area under the curve of 0.75 by the average performance of the 10 newly built models.CONCLUSION The radiomics model based on CT could serve as a promising non-invasive method in differential diagnosis between early and late stage PDAC.

关键词： Pancreatic ductal adenocarcinoma Radiomics Computed tomography American joint Committee on Cancer staging

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Berberine improves central memory formation of CD8^(+)T cells:Implications for design of natural product-based vaccines

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Acta Pharmaceutica Sinica B 2023年第5期13卷 2259-2268页

作者： Mingyan li Yaling Wang lingzhi Zhang Changxing Gao jing jli jiandong jiang Qing Zhu State Key Laboratory of Bioactive Substance and Function of Natural Medicines and Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation StudyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China College of Chinese Materia Medica and Yunnan Key Laboratory of Southern Medicinal Utilization Yunnan University of Chinese MedicineYunnan 650500China

Berberine(BBR)as one of the most effective natural products has been increasingly used to treat various chronic diseases due to its immunosuppressive/tolerogenic activities.However,it is unknown if BBR can be applied without abrogating the efforts of vaccination.Here we show that priming of CD8^(+)T cells in the presence of BBR lead to improved central memory formation(Tcm)with substantially reduced effector proliferation,primarily orchestrated through activation of AMPK and Stat5.Tcm derived from vaccinated mice fed with BBR were able to adoptively transfer protective immunity to naIve recipients.Vaccination of BBR-fed mice conferred better memory protection against infection without losing immediate effector efficacy,suggesting appreciable benefits from using BBR in vaccination.Thus,our study may help to lay the groundwork for mechanistic understanding of the immunomodulatory effects of natural products and their potential use as adjuvant that allows the design of novel vaccines with more desirable properties.

关键词： Berberine CD8^(+)T cell T cell priming Central memory AMPK Stat5 Vaccine design Naturally occurring compound

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