{"id":38635,"date":"2019-12-12T15:38:27","date_gmt":"2019-12-12T13:38:27","guid":{"rendered":"https:\/\/www.iemn.fr\/?p=38635"},"modified":"2019-12-19T11:01:00","modified_gmt":"2019-12-19T09:01:00","slug":"soutenance-de-these-aleksandra-loczechin-les-nanomateriaux-en-carbone-des-alternatives-antibacteriennes-et-antivirales","status":"publish","type":"post","link":"https:\/\/www.iemn.fr\/en\/actualites\/soutenance-de-these-aleksandra-loczechin-les-nanomateriaux-en-carbone-des-alternatives-antibacteriennes-et-antivirales.html","title":{"rendered":"Soutenance de th\u00e8se: Aleksandra LOCZECHIN \u2013 Les nanomat\u00e9riaux en carbone : des alternatives antibact\u00e9riennes et antivirales"},"content":{"rendered":"<div id='layer_slider_1'  class='avia-layerslider main_color avia-shadow  avia-builder-el-0  el_before_av_heading  avia-builder-el-first  container_wrap sidebar_right'  style='height: 261px;'  ><div id=\"layerslider_58_1kwfdcy5y9yr9\" data-ls-slug=\"homepageslider\" class=\"ls-wp-container fitvidsignore ls-selectable\" style=\"width:1140px;height:260px;margin:0 auto;margin-bottom: 0px;\"><div class=\"ls-slide\" data-ls=\"duration:6000;transition2d:5;\"><img loading=\"lazy\" decoding=\"async\" width=\"2600\" height=\"270\" src=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2019\/01\/sliders_news1.jpg\" class=\"ls-bg\" alt=\"\" srcset=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2019\/01\/sliders_news1.jpg 2600w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2019\/01\/sliders_news1-300x31.jpg 300w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2019\/01\/sliders_news1-768x80.jpg 768w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2019\/01\/sliders_news1-1030x107.jpg 1030w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2019\/01\/sliders_news1-1500x156.jpg 1500w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2019\/01\/sliders_news1-705x73.jpg 705w\" sizes=\"auto, (max-width: 2600px) 100vw, 2600px\" \/><ls-layer style=\"font-size:14px;text-align:left;font-style:normal;text-decoration:none;text-transform:none;font-weight:700;letter-spacing:0px;border-style:solid;border-color:#000;background-position:0% 0%;background-repeat:no-repeat;width:180px;height:30px;left:0px;top:231px;line-height:32px;color:#ffffff;border-radius:6px 6px 6px 6px;padding-left:50px;background-color:rgba(0, 0, 0, 0.57);\" class=\"ls-l ls-ib-icon ls-text-layer\" data-ls=\"minfontsize:0;minmobilefontsize:0;\"><i class=\"fa fa-quote-right\" style=\"color:#ffffff;margin-right:0.8em;font-size:1em;transform:translateY( -0.125em );\"><\/i>ACTUALITES<\/ls-layer><\/div><\/div><\/div><div id='after_layer_slider_1'  class='main_color av_default_container_wrap container_wrap sidebar_right'  ><div class='container av-section-cont-open' ><div class='template-page content  av-content-small alpha units'><div class='post-entry post-entry-type-page post-entry-38635'><div class='entry-content-wrapper clearfix'>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-k42rijr5-73db10d23a2e117f1f6badb2e66ebb04\">\n#top .av-special-heading.av-k42rijr5-73db10d23a2e117f1f6badb2e66ebb04{\nmargin:0 0 10px 0;\npadding-bottom:4px;\n}\nbody .av-special-heading.av-k42rijr5-73db10d23a2e117f1f6badb2e66ebb04 .av-special-heading-tag .heading-char{\nfont-size:25px;\n}\n.av-special-heading.av-k42rijr5-73db10d23a2e117f1f6badb2e66ebb04 .av-subheading{\nfont-size:15px;\n}\n<\/style>\n<div  class='av-special-heading av-k42rijr5-73db10d23a2e117f1f6badb2e66ebb04 av-special-heading-h2  avia-builder-el-1  el_after_av_layerslider  el_before_av_hr  avia-builder-el-first'><h2 class='av-special-heading-tag'  itemprop=\"headline\"  >THESE : Les nanomat\u00e9riaux en carbone : des alternatives antibact\u00e9riennes et antivirales<\/h2><div class=\"special-heading-border\"><div class=\"special-heading-inner-border\"><\/div><\/div><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-18u73nj-dad6a947580930e400fc42ba200e80f1\">\n#top .hr.av-18u73nj-dad6a947580930e400fc42ba200e80f1{\nmargin-top:5px;\nmargin-bottom:5px;\n}\n.hr.av-18u73nj-dad6a947580930e400fc42ba200e80f1 .hr-inner{\nwidth:100%;\n}\n<\/style>\n<div  class='hr av-18u73nj-dad6a947580930e400fc42ba200e80f1 hr-custom  avia-builder-el-2  el_after_av_heading  el_before_av_textblock  hr-left hr-icon-no'><span class='hr-inner inner-border-av-border-thin'><span class=\"hr-inner-style\"><\/span><\/span><\/div>\n<section  class='av_textblock_section av-jriy64i8-2f4600354c0449b610997916bbd9b6bc'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" >\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-13ewzjw-68e036126b913e5028f77311dc66b825\">\n.av_font_icon.av-13ewzjw-68e036126b913e5028f77311dc66b825{\ncolor:#bfbfbf;\nborder-color:#bfbfbf;\n}\n.av_font_icon.av-13ewzjw-68e036126b913e5028f77311dc66b825 .av-icon-char{\nfont-size:60px;\nline-height:60px;\n}\n<\/style>\n<span  class='av_font_icon av-13ewzjw-68e036126b913e5028f77311dc66b825 avia_animate_when_visible av-icon-style- avia-icon-pos-left avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue8c9' data-av_iconfont='entypo-fontello' ><\/span><\/span>\n<h5><strong style=\"font-size: 16px;\">Aleksandra LOCZECHIN<\/strong><\/h5>\n<p><strong>Lundi 16 d\u00e9cembre 2019 \u00e0 09h30<br \/>\n<\/strong>IRCICA, 50 avenue de Halley &#8211; Villeneuve d&rsquo;Ascq<\/p>\n<\/div><\/section>\n<section  class='av_textblock_section av-jtefqx33-628129dba2299b2ecd65ebfc92eac29d'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><div  class='hr av-kjh3zw-4dff888f744b728a1aca9b3a0971493a hr-default  avia-builder-el-6  avia-builder-el-no-sibling'><span class='hr-inner'><span class=\"hr-inner-style\"><\/span><\/span><\/div>\n<h5><strong><span style=\"color: #800000;\">Jury:<\/span><\/strong><\/h5>\n<ul>\n<li>Sabine\u00a0SZUNERITS, Professeur, Universit\u00e9 de Lille (Directeur de th\u00e8se)<\/li>\n<li>Nils\u00a0METZLER-NOLTE,\u00a0Professeur,\u00a0Ruhr University Bochum,\u00a0(Co Directeur de th\u00e8se)<\/li>\n<li>Chantal\u00a0PICHON,\u00a0Professeur,\u00a0Universit\u00e9 d&rsquo;Orl\u00e9ans,\u00a0(Rapporteur)<\/li>\n<li>Kevin BRAECKMANS, Professeur, Ghent University, (Rapporteur)<\/li>\n<\/ul>\n<h5>Summary:<\/h5>\n<p>La r\u00e9sistance croissante aux antibiotiques et les limitations dans le d\u00e9veloppement de nouveaux m\u00e9dicaments n\u00e9cessitent la recherche de strat\u00e9gies alternatives afin d\u2019\u00e9radiquer les infections bact\u00e9riennes. Des probl\u00e8mes semblables apparaissent dans le d\u00e9veloppement de th\u00e9rapeutiques antivirales, en raison de l\u2019\u00e9mergence constante de nouveaux virus et leur capacit\u00e9 \u00e0 contourner les th\u00e9rapies par des mutations g\u00e9n\u00e9tiques. Ce travail de recherche examine la potentielle activit\u00e9 antibact\u00e9rienne et\/ou antivirale de nanostructures \u00e0 base de carbone telles que les nanoparticules de diamant et les points quantiques carbon\u00e9s (carbon quantum dots, CQDs), ainsi que l\u2019oxyde de graph\u00e8ne r\u00e9duit (reduced graphene oxide, rGO) combin\u00e9 \u00e0 des cryogels. Les CQDs produits par synth\u00e8se hydrothermale \u00e0 partir de l\u2019acide 4-aminoph\u00e9nylboronique comme pr\u00e9curseur carbon\u00e9 se sont montr\u00e9s efficace en tant qu\u2019inhibiteurs de l\u2019attachement du coronavirus humain HCoV-229E-Luc aux cellules avec une EC50 de 5,2\u00b10.7 \u00b5g mL-1. Les \u00e9tudes m\u00e9canistiques sugg\u00e8rent que les CQDs agissent lors des tout premiers stades de l\u2019infection virale ainsi que lors de l\u2019\u00e9tape de r\u00e9plication du virus. En parall\u00e8le, nous avons tir\u00e9 parti du caract\u00e8re multivalent des CQDs et des nanodiamants pour les modifier en y fixant de courts peptides synth\u00e9tiques antimicrobiens (antimicrobial peptides, AMPs). Ces nanostructures ont \u00e9t\u00e9 test\u00e9es contre des bact\u00e9ries pathog\u00e8nes \u00e0 Gram positif Staphylococcus aureus et \u00e0 Gram n\u00e9gatif Escherichia coli et ont montr\u00e9 une activit\u00e9 antibact\u00e9rienne plus \u00e9lev\u00e9e que celle des AMPs seuls. Dans le cas du rGO combin\u00e9 \u00e0 des cryogels charg\u00e9s en AMPs, l\u2019\u00e9radication des bact\u00e9ries a \u00e9t\u00e9 r\u00e9alis\u00e9e efficacement et \u00e0 la demande en utilisant une irradiation infrarouge comme activateur externe permettant le relargage des AMPs<\/p>\n<h5>Abstract:<\/h5>\n<p>Increasing antibiotic resistance and limited development of new drugs necessitate the search for alternative strategies to eradicate bacterial infections. Similar problems are faced in the development of antiviral therapeutics, due to the constant emergence of new viruses and their ability to escape therapy by genetic mutations. This work investigates the potential antibacterial and\/or antiviral activity of carbon-based nanostructures such as diamond nanoparticles and carbon quantum dots (CQDs) as well as reduced graphene oxide (rGO) in combination with cryogels. CQDs formed by hydrothermal synthesis from 4-aminophenylboronic acid as the carbon precursor showed to be efficient in the inhibition of the viral attachment of human coronavirus HCoV-229E-Luc to cells with an EC50 of 5.2\u00b10.7 \u00b5g mL-1. Mechanistic studies suggest that the CQDs are acting at the early stage of virus infection as well at the viral replication step. In parallel, we took advantage of the multivalent character of CQDs as well as nanodiamonds and modified them with short synthetic antimicrobial peptides (AMPs). Tests of these nanostructures against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli pathogens showed increased antibacterial activity when compared to AMPs alone. In the case of rGO combined with cryogels loaded with AMPs, bacterial eradication was achieved efficiently and on-demand using near-infrared light as an external trigger to release AMPs<\/p>\n<\/div><\/section>","protected":false},"excerpt":{"rendered":"","protected":false},"author":2,"featured_media":38584,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[],"class_list":["post-38635","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-actualites"],"_links":{"self":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/38635","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/comments?post=38635"}],"version-history":[{"count":0,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/38635\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media\/38584"}],"wp:attachment":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media?parent=38635"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/categories?post=38635"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/tags?post=38635"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}