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Synthesis,Urease Inhibition and Molecular Modelling Studies of novel Derivatives of the naturally Occurring b-Amyrenone

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natural Products and Bioprospecting 2019年第1期9卷 49-59页

作者： Jean J.K.Bankeu Hira Sattar Yannick S.F.Fongang Syeda W.Muhammadi Conrad V.Simoben Fidele ntie-Kang Guy R.T.Feuya Marthe A.T.Tchuenmogne Mehreen Lateef bruno n.lenta Muhammad S.Ali Augustin S.ngouela Department of Chemistry Faculty of ScienceThe University of BamendaP.O.Box 39BambiliCameroon International Center for Chemical and Biological Sciences University of KarachiKarachi 75270Pakistan Department of Chemistry Higher Teacher Training CollegeUniversity of MarouaP.O.Box 55MarouaCameroon Department of Pharmaceutical Chemistry Martin-Luther University of Halle-WittenbergWolfgang-Langenbeck-Str.406120 Halle(Saale)Germany Department of Chemistry Faculty of ScienceUniversity of BueaP.O.Box 63BueaCameroon Department of Chemistry Faculty of ScienceScientific and Technical University of MasukuBox 943FrancevilleGabon Department of Chemistry Faculty of ScienceUniversity of Yaounde´IP.O.Box 812Yaounde´Cameroon Multi-Disciplinary Research Laboratory(MDRL) Bahria University Medical and Dental CollegeBahria UniversityKarachiPakistan Department of Chemistry Higher Teacher Training CollegeUniversity of Yaounde´IP.O.Box 47Yaounde´Cameroon

Urease enzyme(UE)has been reported to be a potent virulence factor for Helicobacter pylori(HP)bacteria indicated to be responsible for various gastrointestinal ***,the spread of HP,currently regarded by the World Health Organization as a class 1 carcinogen,could be better controlled by targeting *** is in this line that we have synthesized three new derivatives(2–4)of the naturally occurring olean-12-en-3-one(1),which was previously isolated from the figs of Ficus vallis-choudae Delile(Moraceae).Among the synthesized compounds,3 and 4 contain an indole *** structures were unambiguously assigned by spectroscopic and spectrometric techniques(1D-nMR,2D-nMR and MS).The starting material and the synthesized compounds were screened for UE inhibition activity,and showed significant activities with IC50 values ranging from 14.5 to 24.6 lM,with compound(1)being the most potent as compared to the positive control thiourea(IC50=21.6 lM).Amongst the synthetic derivatives,compound 4 was the most potent(IC50-=17.9 lM),while the others showed activities close to that of the *** addition,molecular docking study of target compounds 2–4 was performed in an attempt to explore their binding mode for the design of more potent UE inhibitors.

关键词： Helicobacter pylori Urease inhibition Docking Olean-12-en-3-one derivatives

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Bone marrow mononuclear cells for joint therapy: The role of macrophages in inflammation resolution and tissue repair

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World Journal of Stem Cells 2021年第7期13卷 825-840页

作者： bruno C Menarim James n MacLeod Linda A Dahlgren Gluck Equine Research Center Department of Veterinary ScienceCollege of AgricultureFood and EnvironmentUniversity of KentuckyLexingtonKY 40546United States Department of Large Animal Clinical Sciences Virginia-Maryland College of Veterinary MedicineVirginia TechBlacksburgVA 24060United States

Osteoarthritis(OA)is the most prevalent joint disease causing major disability and medical *** is a central feature of OA and is primarily driven by *** macrophages not only drive inflammation but also its resolution,through a coordinated,simultaneous expression of pro-and anti-inflammatory mechanisms that are essential to counteract damage and recover *** OA therapies are largely based on anti-inflammatory principles and therefore block pro-inflammatory mechanisms such as prostaglandin E2 and nuclear factor-kappa B signaling ***,such mechanisms are also innately required for mounting a pro-resolving response,and their blockage often results in chronic low-grade *** minor injury,macrophages shield the damaged area and drive tissue *** the damage is more extensive,macrophages incite inflammation recruiting more macrophages from the bone marrow to maximize tissue repair and ultimately resolve ***,sustained damage and inflammation often overwhelms pro-resolving mechanisms of synovial macrophages leading to the chronic inflammation and related tissue degeneration observed in ***,experimental and clinical studies have shown that joint injection with autologous bone marrow mononuclear cells replenishes inflamed joints with macrophage and hematopoietic progenitors,enhancing mechanisms of inflammation resolution,providing remarkable and long-lasting *** creating an ideal environment for resolution with high concentrations of interleukin-10 and anabolic growth factors,macrophage progenitors also have a direct role in tissue *** constitute a large part of the early granulation tissue,and further transdifferentiate from myeloid into a mesenchymal *** cells,characterized as fibrocytes,are essential for repairing osteochondral ***“omics”studies focused on identifying key drivers of macrophagemediated resolution of j

关键词： Osteoarthritis Arthropathy Synovitis Hematopoietic progenitor Homeostasis Cell therapy

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Impact of the polymer backbone chemistry on interactions of amino-acid-derived zwitterionic polymers with cells

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Bioactive Materials 2023年第6期24卷 524-534页

作者： Meike n.Leiske bruno G.De Geest Richard Hoogenboom Supramolecular Chemistry Group Centre of Macromolecular Chemistry(CMaC)Department of Organic and Macromolecular ChemistryGhent UniversityKrijgslaan 281 S4B-9000GhentBelgium Department of Pharmaceutics and Cancer Research Institute Ghent(CRIG) Ghent UniversityOttergemsesteenweg 460B-9000GhentBelgium Faculty of Biology Chemistry&Earth SciencesUniversity of BayreuthUniversitätsstraße 3095447 BayreuthGermany

Zwitterionic polymers are known to interact with cells and have been shown to reveal cancer cell *** this work,the importance of the chemistry of the polymer backbone for the cellular specificity of amino-acid-derived polyzwitterions is demonstrated.A series of glutamic acid(Glu)-based vinyl monomers(i.e.,an acrylate,a methacrylate,an acrylamide,and a methacrylamide)were prepared and used for reversible addition-fragmentation chain-transfer(RAFT)polymerisation,yielding defined polymers with narrow size distribution(Ðnctionalised,zwitterionic polymers revealed high cytocompatibility;however,differences in cellular association and specificity were *** particular,the methacrylamide-derived polymers showed high association with both,breast cancer cells and non-cancerous dendritic cells and,consequently,lack *** contrast,high specificity to only breast cancer cells was observed for polyacrylates,-methacrylates,*** analysis of the polymers revealed differences in hydrophobicity,zeta potential,and potential side chain hydrolysis,which are impacted by the polymer backbone and might be responsible for the altered the cell association of these *** is shown that a slightly negative net charge is preferred over a neutral charge to retain cell *** was also confirmed by association experiments in the presence of competitive amino acid transporter *** affinity of slightly negatively charged Glu-derived polymers to the xCT Glu/cystine cell membrane antiporter was found to be higher than that of neutrally charged *** results emphasise the importance of the polymer backbone for the design of cell-specific *** study further highlights the potential to tailor amino-acid-derived zwitterionic materials beyond their side chain functionality.

关键词： Amino-acid-functionalised polymer Zwitterionic polymer Cell-specific polymer Cancer-targeting RAFT-Polymerisation

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Identifying representative days of solar irradiance and wind speed in Brazil using machine learning techniques

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Energy and AI 2024年第1期15卷 151-170页

作者： Rafaela Ribeiro bruno Fanzeres Industrial Engineering Department Pontifical Catholic University of Rio de Janeiro(PUC-Rio)22451-900Rio de JaneiroRJBrazil

The investment levels in electricity production capacity from variable Renewable Energy Sources have substantially grown in Brazil over the last decades,following the worldwide-seeking-goal of a carbon-neutral economy and the country’s incentives in diversifying its generation *** a long-term perspective,the current non-storable capability of renewable energy sources requires an adequate uncertainty characterization over the *** this context,the main objective of this work is to provide a thorough descriptive analytics of the time-linked hourly-based daily dynamics of wind speed and solar irradiance in the main resourceful regions of *** on unsupervised Machine Learning methods,we focus on identifying similar days over the years,Representative Days,that can depict the fundamental underlying behaviour of each *** analysis is based on a historical dataset of different sites with the highest potential and installed capacity of each source spread over the country:three in the northeast and one in the South Regions,for wind speed;and three in the northeast and one in the Southeast Regions,for solar *** use two Partitioning Methods(𝐾-Means and𝐾-Medoids),the Hierarchical Ward’s Method,and a Model-Based Method(Self-Organizing Maps).We identified that wind speed and solar irradiance can be effectively represented,respectively,by only two representative days,and two or three days,depending on the region and method(segments data with respect to the intensity of each source).Analysis with higher Representative Days highlighted important hidden patterns such as different wind speed modulations and solar irradiance peak-hours along the days.

关键词： Partitioning clustering methods Hierarchical clustering methods Model-based clustering methods Representative days Solar irradiance Wind speed

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L^1-Poincaré and Sobolev inequalities for differential forms in Euclidean spaces Dedicated to Professor Jean-Yves Chemin on the Occasion of His 60th Birthday

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Science China Mathematics 2019年第6期62卷 1029-1040页

作者： Annalisa Baldi bruno Franchi Pierre Pansu Dipartimento di Matematica Università di Bologna Laboratoire de Mathématiques d'Orsay Université Paris-Sud CNRSUniversité Paris-Saclay

In this paper, we prove Poincaré and Sobolev inequalities for differential forms in L^1(R^n). The singular integral estimates that it is possible to use for L^p, p > 1, are replaced here with inequalities which go ba... 详细信息

关键词： differential forms Sobolev-Poincaré inequalities homotopy formula

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A Recursive Basis for Primitive Forms in Symplectic Spaces and Applications to Heisenberg Groups

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Acta Mathematica Sinica,English Series 2016年第3期32卷 265-285页

作者： Annalisa BALDI Marilena BARnABEI bruno FRAnCHI Dipartimento di Matematica Piazza di Porta S.Donato 540126 BolognaItaly

This paper is divided in two parts： in Section 2, we define recursively a privileged basis of the primitive forms in a symplectic space（V^（2n）, ω）. Successively, in Section 3, we apply our construction in the setting of Heisenberg groups H^n, n ≥ 1, to write in coordinates the exterior differential of the so-called Rumin＇s complex of differential forms in H^n.

关键词： Symplectic manifolds differential forms Heisenberg groups combinatorial functions

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Avalonia,get bent!–Paleomagnetism from SW Iberia confirms the Greater Cantabrian Orocline

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Geoscience Frontiers 2021年第2期12卷 805-825页

作者： bruno Daniel Leite Mendes Daniel Pastor-Galan Mark J.Dekkers Wout Krijgsman Paleomagnetic Laboratory Fort Hoofddijk Department of Earth SciencesUtrecht UniversityBudapestlaan 173584CDthe Netherlands Frontier Research Institute for Interdisciplinary Sciences Tohoku UniversityJapan Department Earth Science Tohoku UniversityJapan Center for north East Asia Studies Tohoku University980-857641 KawauchiAoba-kuSendaiMiyagiJapan

The amalgamation of Pangea formed the contorted Variscan-Alleghanian orogen,suturing Gondwana and Laurussia during the *** all swirls of this orogen,a double curve in Iberia stands out,the coupled Cantabrian Orocline and Central Iberian *** Cantabrian Orocline formed at ca.315–290 Ma subsequent to the Variscan *** formation mechanism of the Cantabrian Orocline is disputed,the most commonly proposed mechanisms include either(1)that south-westernmost Iberia would be an Avalonian(Laurussian)indenter or(2)that the stress field changed,buckling the *** contrast,the geometry and kinematics of the Central Iberian curve are largely *** some authors defend both curvatures are genetically linked,others support they are distinct and formed at different *** uncertainty adds an extra layer of complexity to our understanding of the final stages of Pangea’s *** solve these issues,we study the late Carboniferous–early Permian vertical-axis rotations of SW Iberia with *** results show up to 70counterclockwise vertical-axis rotations during late Carboniferous times,concurring with the anticipated kinematics if SW Iberia was part of the southern limb of the Cantabrian *** results do not allow the necessary penecontemporaneous clockwise rotations in Central Iberia to support a concomitant formation of both Cantabrian and Central Iberian *** coherent rotation of both Gondwanan and Avalonian pieces of SW Iberia discards the Laurussian indenter hypothesis as a formation mechanism of the Cantabrian Orocline and confirms the Greater Cantabrian Orocline *** Greater Cantabrian Orocline likely formed as a consequence of a change in the stress field during the late Carboniferous and extended beyond the Rheic Ocean suture affecting the margins of both Laurussia and Gondwana.

关键词： Pangea Variscan orogeny Greater Cantabrian Orocline Paleomagnetism Central Iberian curve

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A new Ceramide (Rumexamide) and Other Chemical Constituents from <i>Rumex abyssinicus</i>Jacq (Polygonaceae): Isolation, Characterization, Antibacterial Activities and Chemophenetic Significance

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Advances in Biological Chemistry 2021年第5期11卷 266-282页

作者： Léonel Donald Feugap Tsamo Lorette Victorine Yimgang Steven Collins n. Wouamba Pierre Mkounga Augustin Ephrem nkengfack Laurence Voutquenne-nazabadioko David ngnokam bruno ndjakou lenta norbert Sewald Research Unit of Applied and Environmental Chemistry Department of Chemistry Faculty of Science University of Dschang Dschang Cameroon Department of Organic Chemistry Faculty of Science University of Yaoundé I Yaoundé Cameroon Antimicrobial Agents Unit Laboratory for Phytobiochemistry and Medicinal Plants Studies University of Yaoundé I Yaoundé Cameroon Department of Chemistry Higher Teacher Training College University of Yaounde I Yaoundé Cameroon Groupe Isolement et Structure Institut de Chimie Moléculaire de Reims (ICMR) Reims France Organic and Bioorganic Chemistry Faculty of Chemistry Bielefeld University Bielefeld Germany

The chemical study of Rumex abyssinicus Jacp (Polygonaceae) led to the isolation of a new ceramide named (R)-2'-hydroxy-n-[(2S,3S,4R,16E)-1,3,4-trihydroxyhexacos-16-en-2-yl]hexadecanamide (rumexamide) (1) together wit... 详细信息

The chemical study of Rumex abyssinicus Jacp (Polygonaceae) led to the isolation of a new ceramide named (R)-2n>'-hydroxy-N-[(2S,3S,4R,16E)-1,3,4-trihydroxyhexacos-16-en-2-yl]hexadecanamide (rumexamide) (1) together with sixteen known compounds: bis-(2-ethylhexyl) phthalate (2), chrysophanol (3), physcion (4), citreorosein (5), emodin (6), chrysophanein (7), physcionin (8), lupeol (9), 3β,28-dihydroxylup-20(29)-ene (10), 3β-dihydroxylup-20(29)-en-28-oic acid (11), oleanolic acid (12), ergosta-6,22-diene-3,5,8-triol (13), stigmastane-3,6-dione (14), a mixture of β-sitosterol (15) and stigmasterol (16), and stigmasterol 3-O-β-D-glucoside (17). Their structures were determined by interpretation of their spectroscopic 1D NMR (1H and 13C NMR), 2D NMR (COSY 1H-1H, HSQC and HMBC) data in conjunction with mass spectrometry (TOFESIMS and HR-TOFESIMS) and by comparison with those reported in the literature. Among all the known compounds, twelve (2, 5, 8n>-17) were firstly isolated from Rumex abyssinicus, seven (2, 10-14 and 17) from the genus Rumex and three (13, 14, 17) from family Polygonaceae. The in vitro antibacterial activities of extracts (MeOH, n-BuOH and EtOAc),n style="font-family:""> as well as compounds 9,

关键词： Polygonaceae Rumex abyssinicus Rumexamide Antibacterial Activities Chemophenetic Significance

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Symmetrization for Fractional Elliptic and Parabolic Equations and an Isoperimetric Application(Dedicated to Haim Brezis,great master of analysis,on his 70th birthday)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 661-686页

作者： Yannick SIRE Juan Luis VAZQUEZ bruno VOLZOnE johns hopkins university Krieger Hall3401 N.Charles StBaltimoreM D21218USA. departamento de matemticas universidad autnoma de madrid28049 M adridSpain dipartimento di ingegneria universit degli studi di napoli"parthenope"80143 Italia.

This paper develops further the theory of symmetrization of fractional Laplacian operators contained in recent works of two of the authors. This theory leads to optimal estimates in the form of concentration comparison inequalities for both elliptic and parabolic equations. The authors extend the theory for the so-called restricted fractional Laplacian defined on a bounded domain Ω of R^n with zero Dirichlet conditions outside of Ω. As an application, an original proof of the corresponding fractional Faber-Krahn inequality is derived. A more classical variational proof of the inequality is also provided.

关键词： Symmetrization, Fractional Laplacian, nonlocal elliptic and parabolicequations, Faber-Krahn inequality

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Planar matrices and arrays of Feynman diagrams

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Communications in Theoretical Physics 2024年第3期76卷 15-32页

作者： Freddy Cachazo Alfredo Guevara bruno Umbert Yong Zhang Perimeter Institute for Theoretical Physics WaterlooON N2L 2Y5Canada Department of Physics and Astronomy University of WaterlooWaterlooON N2L 3G1Canada CECs Valdivia y Departamento de Física Universidad de ConcepciónCasilla 160-CConcepciónChile Center for the Fundamental Laws of nature Society of Fellows and Black Hole InitiativeHarvard UniversityCambridgeMA 02138United States of America Department of Applied Mathematics Western UniversityLondonON N6A 5B7Canada CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan RoadBeijing 100049China

Recently,planar collections of Feynman diagrams were proposed by Borges and one of the authors as the natural generalization of Feynman diagrams for the computation of k=3 biadjoint *** collections are one-dimensional arrays of metric trees satisfying an induced planarity and compatibility *** this work,we introduce planar matrices of Feynman diagrams as the objects that compute k=4 biadjoint *** are symmetric matrices of metric trees satisfying compatibility *** introduce two notions of combinatorial bootstrap techniques for finding collections from Feynman diagrams and matrices from *** applications of the first,we find all 693,13612 and 346710 collections for(k,n)=(3,7),(3,8)and(3,9),*** applications of the second kind,we find all90608 and 30659424 planar matrices that compute(k,n)=(4,8)and(4,9)biadjoint amplitudes,*** an example of the evaluation of matrices of Feynman diagrams,we present the complete form of the(4,8)and(4,9)biadjoint *** also start a study of higher-dimensional arrays of Feynman diagrams,including the combinatorial version of the duality between(k,n)and(n-k,n)objects.

关键词： Feynman diagrams biadjoint amplitudes tropical Grassmannian

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