Le Carcinome Hépatocellulaire a une incidence mondiale élevée et est associé à un mauvais pronostic. Les traitements curatifs existants ne sont applicables qu’à une minorité de patients. La radiothérapie sélective interne (SIRT) est un traitement palliatif de plus en plus utilisé. Elle consiste à l’injection sélective intra-tumorale de microsphères d’yttrium-90 par infusion intra-artérielle, et repose sur deux étapes : une étape pré-thérapeutique de simulation du traitement avec l’injection de macroagrégats d’albumines marqués au 99mTc et le traitement en lui-même. Cependant les caractéristiques de ces deux vecteurs diffèrent et peuvent conduire à des variations de biodistribution et à une dosimétrie approximative. Ce travail a pour but de développer un vecteur radiothéranostique unique pour la SIRT : les microparticules à base d’amidon (SBMP), afin de pallier aux différents problèmes rencontrés en clinique. L’optimisation du radiomarquage par le 68Ga et le 188Re sous forme de kits lyophilisés prêts-à-l’emploi, a permis d’obtenir une pureté radiochimique > 98 % et > 95 % respectivement. Une étude préliminaire par imagerie TEP/TDM in vivo chez le rat, suite à l’injection intraartérielle des 68Ga-SBMP a montré une biodistribution spécifique des microparticules avec plus de 95 % de l’activité retrouvée dans le foie et plus particulièrement dans les tumeurs. Les SBMP offrent plusieurs avantages répondant à différents problèmes actuels et constituent un agent théranostique prometteur pour la SIRT. Une présentation de la SIRT, des différentes microparticules en développement pour la SIRT et des modèles animaux de tumeur hépatique existants seront également développées dans ce travail. / The Hepatocellular Carcinoma has a high incidence worldwide and is associated with a bad prognostic. The existing curative treatments can only be apply in a minority of cases. The selective internal radiation therapy (SIRT) is a palliative treatment that is increasingly used. This technique is define by the selective intratumoral injection of yttrium-90microspheres via intra-arterial infusion. It involves two steps : a pre-therapeutic one for treatment simulation purpose with the injection of serum albumin macroaggregates radiolabeled with 99mTc and the treatment itself. However the characteristics of these two vectors are different and can lead to variations in biodistribution and approximate dosimetry. This works aims to develop a unique radiotheranostic vector for the SIRT: the starch-basedmicroparticles (SBMP), in order to overcome the different currents clinical problems. The optimization of the radiolabeling by the 68Ga and the 188Re in the form of ready-to-use radiolabeling kits allowed to obtain a radiochemical purity > 98 % and > 95 % respectively. A preliminary in vivo study by PET/CT imaging in rat, following the intra-arterial injection of 68Ga-SBMP displayed a specific biodistribution of the microparticles with more than 95 % of the activity found in the liver and mostly in the tumors. The SBMP offer several advantages that answer different current issues and area promising theranostic agent for the SIRT. A presentation of the SIRT, the different microparticles in development and the existing animal models of hepatic tumor will also be developed in this work.

<p>Gliklazid je jedan od najče&scaron;će kori&scaron;ćenih lekova u terapiji dijabetes melitusa tip 2. U poslednje vreme, utvrđeno je da gliklazid ispoljava i druge pozitivne farmakolo&scaron;ke efekte kao &scaron;to su imunomodulatorni i anti-koagulacioni efekti, ukazujući na njegovu potencijalnu primenu u terapiji dijabetes melitusa tip 1. Gliklazid se odlikuje varijabilnim stepenom apsorpcije nakon peroralne primene i iz tog razloga pretpostavlja se da bi tehnike njegove ciljane isporuke, kao &scaron;to je mikroinkapsulacija, mogle da dovedu do pobolj&scaron;anja njegove apsorpcije i njegove potencijalne primene u terapiji T1DM. Pokazano je da različite žučne kiseline, uključujući i holnu, imaju stabilizacione efekte u domenu primene mikrovezikula i kontrolisanog osobađanja lekova, te je moguće da bi njihov dodatak u mikrovezikularnu formulaciju gliklazida mogao dodatno da pobolj&scaron;a oslobađanje gliklazida, njegovu apsorpciju i antidijabetičke efekte. S tim u vezi, cilj ovog istraživanja je da se ispita hipoglikemijski efekat gliklazida primenjenog u obliku alginatnih mikrovezikula, sa ili bez dodatka holne kiseline na T1DM modelu pacova. Trideset &scaron;est pacova obolelih od T1DM indukovanog aloksanom i odgovarajuće zdrave kontrolne životinje su nasumično raspoređene u &scaron;est grupa (n=6) i tretirane jednokratnom dozom fiziolo&scaron;kog rastvora, suspenzijom gliklazida, gliklazidom u obliku alginatnih mikrovezikula, samo holnom kiselinom, i mikrovezikulama gliklazida sa ili baz dodatka holne kiseline. Uzorkovana je krv tokom 10 h nakon unete doze i merena je koncentracija glukoze u krvi I koncentracija gliklazida u serumu kori&scaron;ćenjem HPLC metode. Mikrovezikule gliklazida su ispoljile hipo-glikemijski efekat kod pacova obolelih od dijabetesa, uprkos njegovim smanjenim koncentracijama u serumu, dok je dodatak holne kiseline u mikrovezikularnu formulaciju smanjio hipoglikemijski efekat gliklazida. Ovo potvrđuje izostanak sinergističkog efekta između gliklazida i holne kiseline. Takođe, ni proces mikroinkapsulacije niti dodatak holne kiseline nisu doprineli pobolj&scaron;anju apsorpcije gliklazida, &scaron;to ukazuje na činjenicu da su njegovi hipoglikemijski efekti nezavisni od njegove apsorpcije i koncentracije u serumu. Stoga se može pretpostaviti da su hipoglikemijski efekti gliklazida pre pod uticajem crevno-metaboličke aktivacije nego ciljanog oslobađanja u digestivnom traktu sistemske apsorpcije. Mikrovezikule gliklazida ispoljavaju hipoglikemijski efekat kod pacova obolelih od T1DM nezavisno od insulina, te mogu imati potencijalnu primenu u terapiji T1DM. Ovaj rad su podržali: HORIZON 2020 MEDLEM projekat broj 690876; Projekat Sekretarijata naučnog i tehnolo&scaron;kog razvoja Vojvodine broj . 114-451-2072-/2016-02; Projekat Ministarstva obrazovanja, nauke i tehnolo&scaron;kog razvoja Republike Srbije broja 41012.</p> / <p><!--[if gte mso 9]><xml> <o:DocumentProperties> <o:Author>mladen</o:Author> <o:Version>16.00</o:Version> </o:DocumentProperties> <o:OfficeDocumentSettings> <o:AllowPNG/> </o:OfficeDocumentSettings></xml><![endif]--><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:TrackMoves/> <w:TrackFormatting/> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:DoNotPromoteQF/> <w:LidThemeOther>EN-US</w:LidThemeOther> <w:LidThemeAsian>X-NONE</w:LidThemeAsian> <w:LidThemeComplexScript>X-NONE</w:LidThemeComplexScript> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <w:DontGrowAutofit/> <w:SplitPgBreakAndParaMark/> <w:EnableOpenTypeKerning/> <w:DontFlipMirrorIndents/> <w:OverrideTableStyleHps/> </w:Compatibility> <m:mathPr> <m:mathFont m:val="Cambria Math"/> <m:brkBin m:val="before"/> <m:brkBinSub m:val="&#45;-"/> <m:smallFrac m:val="off"/> <m:dispDef/> <m:lMargin m:val="0"/> <m:rMargin m:val="0"/> <m:defJc m:val="centerGroup"/> <m:wrapIndent m:val="1440"/> <m:intLim m:val="subSup"/> <m:naryLim m:val="undOvr"/> </m:mathPr></w:WordDocument></xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" DefUnhideWhenUsed="false" DefSemiHidden="false" DefQFormat="false" DefPriority="99" LatentStyleCount="371"> <w:LsdException Locked="false" Priority="0" QFormat="true" Name="Normal"/> <w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 1"/> <w:LsdException Locked="false" Priority="9" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="heading 2"/> <w:LsdException Locked="false" Priority="9" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="heading 3"/> <w:LsdException Locked="false" Priority="9" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="heading 4"/> <w:LsdException Locked="false" Priority="9" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="heading 5"/> <w:LsdException Locked="false" Priority="9" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="heading 6"/> <w:LsdException Locked="false" Priority="9" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="heading 7"/> <w:LsdException Locked="false" Priority="9" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="heading 8"/> <w:LsdException Locked="false" Priority="9" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="heading 9"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 5"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 6"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 7"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 8"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index 9"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 1"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 2"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 3"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 4"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 5"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 6"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 7"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 8"/> <w:LsdException Locked="false" Priority="39" SemiHidden="true" UnhideWhenUsed="true" Name="toc 9"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Normal Indent"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="footnote text"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="annotation text"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="header"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="footer"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="index heading"/> <w:LsdException Locked="false" Priority="35" SemiHidden="true" UnhideWhenUsed="true" QFormat="true" Name="caption"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="table of figures"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="envelope address"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="envelope return"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="footnote reference"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="annotation reference"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="line number"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="page number"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="endnote reference"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="endnote text"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="table of authorities"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="macro"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="toa heading"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Bullet"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Number"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List 5"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Bullet 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Bullet 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Bullet 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Bullet 5"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Number 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Number 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Number 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Number 5"/> <w:LsdException Locked="false" Priority="10" QFormat="true" Name="Title"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Closing"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Signature"/> <w:LsdException Locked="false" Priority="1" SemiHidden="true" UnhideWhenUsed="true" Name="Default Paragraph Font"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Body Text"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Body Text Indent"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Continue"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Continue 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Continue 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Continue 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="List Continue 5"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Message Header"/> <w:LsdException Locked="false" Priority="11" QFormat="true" Name="Subtitle"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Salutation"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Date"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Body Text First Indent"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Body Text First Indent 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Note Heading"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Body Text 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Body Text 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Body Text Indent 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Body Text Indent 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Block Text"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Hyperlink"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="FollowedHyperlink"/> <w:LsdException Locked="false" Priority="22" QFormat="true" Name="Strong"/> <w:LsdException Locked="false" Priority="20" QFormat="true" Name="Emphasis"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Document Map"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Plain Text"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="E-mail Signature"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Top of Form"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Bottom of Form"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Normal (Web)"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Acronym"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Address"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Cite"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Code"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Definition"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Keyboard"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Preformatted"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Sample"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Typewriter"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="HTML Variable"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Normal Table"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="annotation subject"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="No List"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Outline List 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Outline List 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Outline List 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Simple 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Simple 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Simple 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Classic 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Classic 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Classic 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Classic 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Colorful 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Colorful 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Colorful 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Columns 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Columns 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Columns 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Columns 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Columns 5"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Grid 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Grid 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Grid 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Grid 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Grid 5"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Grid 6"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Grid 7"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Grid 8"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table List 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table List 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table List 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table List 4"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table List 5"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table List 6"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table List 7"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table List 8"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table 3D effects 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table 3D effects 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table 3D effects 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Contemporary"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Elegant"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Professional"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Subtle 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Subtle 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Web 1"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Web 2"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Web 3"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Balloon Text"/> <w:LsdException Locked="false" Priority="39" Name="Table Grid"/> <w:LsdException Locked="false" SemiHidden="true" UnhideWhenUsed="true" Name="Table Theme"/> <w:LsdException Locked="false" SemiHidden="true" Name="Placeholder Text"/> <w:LsdException Locked="false" Priority="1" QFormat="true" Name="No Spacing"/> <w:LsdException Locked="false" Priority="60" Name="Light Shading"/> <w:LsdException Locked="false" Priority="61" Name="Light List"/> <w:LsdException Locked="false" Priority="62" Name="Light Grid"/> <w:LsdException Locked="false" Priority="63" Name="Medium Shading 1"/> <w:LsdException Locked="false" Priority="64" Name="Medium Shading 2"/> <w:LsdException Locked="false" Priority="65" Name="Medium List 1"/> <w:LsdException Locked="false" Priority="66" Name="Medium List 2"/> <w:LsdException Locked="false" Priority="67" Name="Medium Grid 1"/> <w:LsdException Locked="false" Priority="68" Name="Medium Grid 2"/> <w:LsdException Locked="false" Priority="69" Name="Medium Grid 3"/> <w:LsdException Locked="false" Priority="70" Name="Dark List"/> <w:LsdException Locked="false" Priority="71" Name="Colorful Shading"/> <w:LsdException Locked="false" Priority="72" Name="Colorful List"/> <w:LsdException Locked="false" Priority="73" Name="Colorful Grid"/> <w:LsdException Locked="false" Priority="60" Name="Light Shading Accent 1"/> <w:LsdException Locked="false" Priority="61" Name="Light List Accent 1"/> <w:LsdException Locked="false" Priority="62" Name="Light Grid Accent 1"/> <w:LsdException Locked="false" Priority="63" Name="Medium Shading 1 Accent 1"/> <w:LsdException Locked="false" Priority="64" Name="Medium Shading 2 Accent 1"/> <w:LsdException Locked="false" Priority="65" Name="Medium List 1 Accent 1"/> <w:LsdException Locked="false" SemiHidden="true" Name="Revision"/> <w:LsdException Locked="false" Priority="34" QFormat="true" Name="List Paragraph"/> <w:LsdException Locked="false" Priority="29" QFormat="true" Name="Quote"/> <w:LsdException Locked="false" Priority="30" QFormat="true" Name="Intense Quote"/> <w:LsdException Locked="false" Priority="66" Name="Medium List 2 Accent 1"/> <w:LsdException Locked="false" Priority="67" Name="Medium Grid 1 Accent 1"/> <w:LsdException Locked="false" Priority="68" Name="Medium Grid 2 Accent 1"/> <w:LsdException Locked="false" Priority="69" Name="Medium Grid 3 Accent 1"/> <w:LsdException Locked="false" Priority="70" Name="Dark List Accent 1"/> <w:LsdException Locked="false" Priority="71" Name="Colorful Shading Accent 1"/> <w:LsdException Locked="false" Priority="72" Name="Colorful List Accent 1"/> <w:LsdException Locked="false" Priority="73" Name="Colorful Grid Accent 1"/> <w:LsdException Locked="false" Priority="60" Name="Light Shading Accent 2"/> <w:LsdException Locked="false" Priority="61" Name="Light List Accent 2"/> <w:LsdException Locked="false" Priority="62" Name="Light Grid Accent 2"/> <w:LsdException Locked="false" Priority="63" Name="Medium Shading 1 Accent 2"/> <w:LsdException Locked="false" Priority="64" Name="Medium Shading 2 Accent 2"/> <w:LsdException Locked="false" Priority="65" Name="Medium List 1 Accent 2"/> <w:LsdException Locked="false" Priority="66" Name="Medium List 2 Accent 2"/> <w:LsdException Locked="false" Priority="67" Name="Medium Grid 1 Accent 2"/> <w:LsdException Locked="false" Priority="68" Name="Medium Grid 2 Accent 2"/> <w:LsdException Locked="false" Priority="69" Name="Medium Grid 3 Accent 2"/> <w:LsdException Locked="false" Priority="70" Name="Dark List Accent 2"/> <w:LsdException Locked="false" Priority="71" Name="Colorful Shading Accent 2"/> <w:LsdException Locked="false" Priority="72" Name="Colorful List Accent 2"/> <w:LsdException Locked="false" Priority="73" Name="Colorful Grid Accent 2"/> <w:LsdException Locked="false" Priority="60" Name="Light Shading Accent 3"/> <w:LsdException Locked="false" Priority="61" Name="Light List Accent 3"/> <w:LsdException Locked="false" Priority="62" Name="Light Grid Accent 3"/> <w:LsdException Locked="false" Priority="63" Name="Medium Shading 1 Accent 3"/> <w:LsdException Locked="false" Priority="64" Name="Medium Shading 2 Accent 3"/> <w:LsdException Locked="false" Priority="65" Name="Medium List 1 Accent 3"/> <w:LsdException Locked="false" Priority="66" Name="Medium List 2 Accent 3"/> <w:LsdException Locked="false" Priority="67" Name="Medium Grid 1 Accent 3"/> <w:LsdException Locked="false" Priority="68" Name="Medium Grid 2 Accent 3"/> <w:LsdException Locked="false" Priority="69" Name="Medium Grid 3 Accent 3"/> <w:LsdException Locked="false" Priority="70" Name="Dark List Accent 3"/> <w:LsdException Locked="false" Priority="71" Name="Colorful Shading Accent 3"/> <w:LsdException Locked="false" Priority="72" Name="Colorful List Accent 3"/> <w:LsdException Locked="false" Priority="73" Name="Colorful Grid Accent 3"/> <w:LsdException Locked="false" Priority="60" Name="Light Shading Accent 4"/> <w:LsdException Locked="false" Priority="61" Name="Light List Accent 4"/> <w:LsdException Locked="false" Priority="62" Name="Light Grid Accent 4"/> <w:LsdException Locked="false" Priority="63" Name="Medium Shading 1 Accent 4"/> <w:LsdException Locked="false" Priority="64" Name="Medium Shading 2 Accent 4"/> <w:LsdException Locked="false" Priority="65" Name="Medium List 1 Accent 4"/> <w:LsdException Locked="false" Priority="66" Name="Medium List 2 Accent 4"/>

L'objectif principal de ce travail était de comparer l'implication (i) de cellules vasculaires, cellules musculaires lisses vasculaires (CML) et cellules endothéliales (CE), ou des cellules circulantes, les plaquettes, et (ii) des microparticules (MP) issues de ces différentes cellules dans la génération de la thrombine mais également dans son inhibition par les systèmes anticoagulants de la protéine C activée (PCa) et de l'inhibiteur de la voie du facteur tissulaire (TFPI), et d'identifier les mécanismes et les déterminants responsables des différences observées entre ces supports cellulaires pour la coagulation. Nous avons démontré que l'intégrine [alpha]v[gamma]3 qui est le récepteur pour la prothrombine sur les surfaces vasculaires était impliquée dans la génération de thrombine à la surface des CML soumises ou non à des déformations mécaniques cycliques. A l'état de base, les CML et les CE ont un potentiel thrombinique similaire, mais moins important que celui des plaquettes. Nous avons montré un rôle synergique du TFPI avec la PCa dans l'inhibition de la génération de thrombine à la surface de ces cellules plus importante avec les CML qu'avec les CE. L'ensemble de nos résultats suggère que les CML pourraient exercer des effets procoagulants comparables aux CE mais avec des régulations différentes en réponse aux facteurs pro- et anticoagulants, et que les MP issues de cellules vasculaires ont un pouvoir thrombogène très supérieur à leurs cellules d'origine / The main objective of this study was to compare the implication (i) of vascular cells, smooth muscle cells (SMC) and endothelial cells (EC), or circulating cells, platelets, and (ii) microparticles (MP) derived from these different cells in the generation of thrombin but also in its inhibition by the activated protein C (APC) and the tissue factor pathway inhibitor (TFPI), and to identify the mechanisms and determinants responsibles for observed differences between these different cell supports for coagulation. We have demonstrated that [alpha]v[gamma]3 integrin, the prothrombin receptor on the vascular surfaces, was involved in the generation of thrombin on the surface of these cells subjected or not subjected to cyclic mechanical deformations. At baseline, SMC and EC, have equivalent thrombin generating capacities, but less than that of platelets. We have shown a synergistic role of TFPI with APC in the inhibition of thrombin generation at the surface of these cells, more important with SMC than with EC. Taken together, our results suggest that SMC may exert procoagulant effects comparable to EC but with different regulations in response to pro-and anticoagulant factors, and that MP derived from vascular cells have a very higher thrombogenic activity compared to their parent cells

Made available in DSpace on 2017-07-21T14:13:05Z (GMT). No. of bitstreams: 1 Amanda Lyra.pdf: 6099284 bytes, checksum: 8701070289c9fd679c58cb469286e18a (MD5) Previous issue date: 2016-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The efavirenz is the first choice drug of non-nucleoside reverse transcriptase inhibitors used in the treatment of HIV-1 infections. It belongs to class II of the Biopharmaceutics Classification System and your therapeutic dose is of 600 mg, taken before bedtime due the side effects. With the aim of improve the drug’s bioavailability with possible reduction of side effects, microparticles with Eudragit® L100 or S100 were developed by spray drying. The formulations M1 to M4 were prepared in ethanol:water (50:50, V/V) and M5 to M8 in ethanol:phosphate buffer pH 7.4 (50:50, V/V). Microparticles were obtained with yield (40 - 70%), humidity (1.41 - 5.77%), particle size (2.02 - 4.07 μm) and zeta potential (-61 to -43) suitable. The drug’s quantification was realized by high performance liquid chromatography analytical method developed and validated. The method proved to be specific, linear (r = 0.9997, n = 3), precise, accurate and robust in a range of 8.0 to 50.0 μg.mL-1, with analysis and retention time of 5.0 and 3.5 minutes, respectively. M1 to M4 showed spherical morphology with drug content between 90 - 104%, and M5 to M8 exhibited flattened and distorted morphology with drug content between 67 - 75%. No chemical interactions was observed in the Fourier transformed infrared spectrum for microparticles M1 to M4. However, there enlargement and increased intensity of some bands in the spectra of microparticles M5 to M8, suggesting a modification of chemical bonds. The thermal analysis and X ray diffraction indicated that the incorporation of EFV into the microparticles contributed to the amorphization of the drug. In vitro drug release confirmed the low solubility of the drug in water (22.88%). The microparticles released less than 22% in acid medium promoting higher release at pH 6.8. All formulations evaluated increased the drug solubility and dissolution efficiency, and exhibited biexponential release kinetics according to the applied mathematical models, being interesting strategies to increase the drug’s bioavailability. The M3 accounted for the major release in pH 6.8 (73.69%) and, according to the Korsmeyer-Peppas model showed anomalous transport characteristics (diffusion and erosion of the polymer), while in other microparticles the release process was controlled by diffusion. In in vitro assay the animals subjected to the administration of M3 exhibited less alterations in the biochemical parameters compared to treatment group EFV, suggesting that the microparticles contributed to the reduction of side effects such as increase in cholesterol, LDL, HDL and triglycerides plasmatic levels. It was observed decay in the quantification of pure drug during the period evaluated in the stability study. The microparticles showed no significant changes in the content of EFV during the 180 days. The thermograms showed no difference in the drug melting range and decays of thermogravimetric curves suggesting no formation of new products and consequently loss of stability. The evaluation of Carr index and Hausner factor indicated that M3 showed better flow and compression properties compared to pure EFV, characteristics which can improving the flow and to facilitate industrial routine. / O efavirenz (EFV) é o fármaco de primeira escolha da classe dos inibidores da transcriptase reversa não análogos de nucleosídeo utilizado no tratamento de infecções por HIV-1. Pertence à classe II do sistema de classificação biofarmacêutico e sua dose terapêutica é de 600 mg, tomados antes de dormir devido aos efeitos colaterais. Com objetivo de melhorar a biodisponibilidade do fármaco com possível redução dos efeitos colaterais, foram desenvolvidas micropartículas com Eudragit® L100 ou S100, por spray drying. As formulações M1 a M4 foram preparadas em etanol:água (50:50, V/V), e M5 a M8 em etanol:tampão fosfato pH 7,4 (50:50, V/V). Foram obtidas micropartículas com rendimentos (40 – 70%), umidades (1,41 – 5,77%), tamanhos de partícula (2,02 – 4,07 μm) e potenciais zeta (-61 a -43 mV) adequados. A quantificação do fármaco foi realizada por meio do método analítico por cromatografia líquida de alta eficiência desenvolvido e validado. O método mostrou-se específico, linear (r = 0,9997, n = 3), preciso, exato e robusto, na faixa de 8,0 a 50,0 μg.mL-1, com tempo de corrida e o tempo de retenção de 5,0 e 3,5 minutos, respectivamente. M1 a M4 apresentaram morfologia esférica, com teor de fármaco entre 90 – 104%, e M5 a M8 exibiram morfologia achatada e distorcida, com teor de fármaco entre 67 – 75%. Nenhuma interação química foi observada nos espectros de infravermelho por transformada em Fourier para as micropartículas M1 a M4. No entanto, houve alargamento e aumento da intensidade de algumas bandas nos espectros das micropartículas M5 a M8, sugerindo uma modificação nas ligações químicas. As análises térmicas e de difração de raios X indicaram que a incorporação do EFV às micropartículas contribuiu para a amorfização do fármaco. Ensaios de liberação in vitro confirmaram a baixa solubilidade do fármaco em água (22,88%). As micropartículas liberaram menos de 22% em meio ácido, promovendo maior liberação em pH 6,8. Todas as formulações avaliadas aumentaram a solubilidade e a eficiência de dissolução do fármaco, e exibiram cinética de liberação biexponencial, segundo os modelos matemáticos aplicados, sendo estratégias interessantes para o aumento da biodisponibilidade do fármaco. A M3 foi responsável pela maior liberação em pH 6,8 (73,69%) e, de acordo com o modelo de Korsmeyer-Peppas, apresentou características de transporte anômalo (difusão e erosão do polímero), enquanto que nas demais micropartículas o processo de liberação foi controlado por difusão. No ensaio in vivo, os animais submetidos à administração de M3 apresentaram menos alterações nos parâmetros bioquímicos, quando comparados ao grupo de tratamento com EFV, sugerindo que as micropartículas contribuíram para a redução dos efeitos colaterais tais como aumento nos níveis plasmáticos de colesterol, LDL e HDL e triglicerídeos. Foi observado um decaimento na quantificação do fármaco puro durante o período avaliado no estudo de estabilidade. As micropartículas não mostraram mudanças significativas no teor de EFV durante 180 dias. Os termogramas indicaram que não houve diferença na faixa de fusão do fármaco e nos decaimentos das curvas termogravimétricas, sugerindo que não houve formação de novos produtos e, consequentemente, perda da estabilidade. A avaliação do índice de Carr e do fator de Hausner indicou que a M3 apresentou melhores propriedades de fluxo e de compactação quando comparadas ao EFV puro, características que podem melhorar o escoamento e facilitar a rotina industrial.

Made available in DSpace on 2017-07-21T14:13:10Z (GMT). No. of bitstreams: 1 Fernanda Malaquias Barbosa.pdf: 3020021 bytes, checksum: d88917643a806ad362e493cbc6e1776b (MD5) Previous issue date: 2013-02-21 / Manidipine is a third-generation calcium channel blocking effective in the treatment of hypertension, which its use has been related to further metabolic effects of potential clinical interest. However, its high lipophilicity results in undesirable physicochemical and biopharmaceutical properties. Thus, a pharmaceutical improvement is necessary to achieve a remarkable advance in its absorption and bioavailability. In that sense, the aim of this paper was to microencapsulate the manidipine in order to avoid its spontaneous compartmentalization in adipocytes and make its intestinal transit longer, with appropriate release rates and duration to generate the desired antihypertensive effect. Poly(ε-caprolactone) (PCL) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) microparticles containing manidipine were successfully prepared by simple emulsion/solvent evaporation method. Considering the lack of validated methods for drug quantification in these microparticles, an analytical method by high efficiency liquid chromatography with spectrometric detection in the ultraviolet region was previously developed and validated. This method proved to be selective, linear (r = 0.9992), precise (RSD < 2.08 %) and accurate (recovery capacity between 95.02 and 100.41%) in the range from 10 to 50 μg.mL-1. The chromatography was robust when underwent slight variations in the mobile phase composition and column temperature. All four formulations showed loading efficiency rates greater than 80% and average particle sizes less than 8 μm. Microparticulate systems showed a spherical shape with smooth and porous surface for PCL and PHBV formulations, respectively. According to Fourier-transformed infrared analysis, initial components were not chemically modified during microencapsulation process, whereas X-ray diffraction patterns and differential scanning calorimetry analysis demonstrated that this process led to drug amorphization. In vitro dissolution profile showed that all microparticles prepared were able to sustain manidipine release, especially which one prepared from PCL, that contained 5% of the drug loaded (PCL-M5). Animal studies demonstrated that PCL-M5 formulation was able to hold the mean arterial pressure variation after phenylephrine administration up to 24 hours. These data demonstrate the sustained antihypertensive effect of the proposed microparticles. Results provided an experimental basis for using PCL-M5 formulation as an oral manidipine carrier. / A manidipina é um bloqueador de canal de cálcio de terceira geração, eficaz no tratamento da hipertensão arterial. Seu uso está relacionado a efeitos metabólicos adicionais de potencial interesse clínico. Entretanto, sua extrema lipofilicidade resulta em propriedades físico-químicas e farmacocinéticas indesejáveis. Assim, torna-se necessário um aprimoramento farmacotécnico para alcançar um avanço expressivo na absorção e na biodisponibilidade desse fármaco. Com esse propósito, o objetivo deste trabalho foi microencapsular a manidipina a fim de evitar sua compartimentalização espontânea nos adipócitos e prolongar seu tempo de trânsito intestinal, com taxas de liberação e duração adequadas para gerar o efeito anti-hipertensivo desejado. Micropartículas de poli(ε-caprolactona) (PCL) e poli(3-hidroxibutirato-co-hidroxivalerato) (PHBV) contendo manidipina foram preparadas com êxito pelo método de emulsão simples/evaporação do solvente orgânico. Diante da ausência de métodos validados para quantificação do fármaco encapsulado nestas micropartículas, um método para o doseamento por cromatografia líquida de alta eficiência com detecção espectrométrica na região do ultravioleta foi previamente desenvolvido e validado. Esse método mostrou-se seletivo, linear (r = 0,9992), preciso (DPR < 2,08 %) e exato (capacidade de recuperação entre 95,02 e 100,41%) no intervalo de 10 a 50 μg.mL-1. Além disso, a cromatografia foi robusta quando submetida a pequenas variações na composição da fase móvel e temperatura da coluna. As quatro formulações apresentaram eficiências de encapsulação superiores a 80% e tamanhos médios de partícula inferiores a 8 μm. Os sistemas microparticulados apresentaram uma forma esférica com superfície lisa e porosa para as formulações de PCL e PHBV, respectivamente. De acordo com as análises por espectroscopia na região do infravermelho com transformada de Fourier, os componentes iniciais não foram quimicamente alterados durante o processo de microencapsulação, ao passo que as análises de difratometria de raios-X e de calorimetria exploratória diferencial demonstraram que esse processo levou a amorfização do fármaco. Os perfis de dissolução in vitro confirmaram a capacidade que as micropartículas apresentam de prolongar a liberação da manidipina, especialmente àquelas preparadas a partir da PCL, que continham 5% de fármaco encapsulado (PCL-M5). Os estudos em animais mostraram que a formulação PCL-M5 foi capaz de minimizar a variação da pressão arterial média, frente à administração de fenilefrina, por até 24 horas. Este dado confirma o efeito anti-hipertensivo prolongado da micropartícula proposta. Os resultados forneceram um embasamento experimental que viabiliza o uso da formulação PCL-M5 como um carreador oral da manidipina.

"The next generation of aluminum alloys will have to operate at temperatures approaching 300°C. Traditional aluminum alloys cannot perform at these temperatures, but aluminum alloys reinforced with fine ceramic particles can. The objective of this research is to develop a process to synthesize Al-TiC composites by the Rotating Impeller Gas-Liquid In-situ method. This method relies on injecting methane into molten aluminum that has been pre-alloyed with titanium. The gas is introduced by means of a rotating impeller into the molten alloy, and under the correct conditions of temperature, gas flow, and rotation speed, it reacts preferentially with titanium to form titanium carbide particles. The design of the apparatus, the multi-physics phenomena underlying the mechanism responsible for particle formation and size control, and the operation window for the process are first elucidated. Then a parametric study that leads to the synthesis of aluminum reinforced with TiC microparticles and nanoparticles is described. Finally, potential technical obstacles that may stand in the way of commercializing the process are discussed and ways to overcome them are proposed. "

Dans le domaine pharmaceutique, la voie orale demeure la voie d’administration de prédilection, car plus simple et mieux acceptée par les patients. Cependant, ce mode d’administration pose problème pour de nombreux principes actifs (PA) présentant une faible solubilité, une faible perméabilité et/ou une instabilité dans l’environnement gastro-intestinal. Leur micro-encapsulation dans des matrices polymériques peut permettre d’y répondre, notamment si les microparticules générées résistent aux environnements rencontrés lors du tractus gastro-intestinal et jouent alors un rôle protecteur, tant pour le principe actif que pour les muqueuses rencontrées. La recherche de nouveaux excipients, issus des agro-ressources tels que les polymères naturels, est en plein essor. Les protéines végétales, grâce à leurs propriétés fonctionnelles telles qu’une bonne solubilité, une viscosité relativement basse, et des propriétés émulsifiantes et filmogènes, représentent des candidats privilégiés. De plus, la grande diversité de leurs groupements fonctionnels permet d’envisager des modifications chimiques ou enzymatiques variées. L’objectif de ce travail était d’étudier l’intérêt de la protéine de soja en tant que matériau enrobant de principes actifs pharmaceutiques destinés à la voie orale, et plus particulièrement en tant que candidat pour l’élaboration de formes gastro-résistantes. Un isolat protéique de soja (SPI) été utilisé comme matière enrobante et l’atomisation comme procédé. L’ibuprofène, anti-inflammatoire non stéroïdien, a été choisi comme molécule modèle du fait de sa faible solubilité nécessitant une amélioration de sa biodisponibilité, et de ses effets indésirables gastriques nécessitant une mise en forme entérique. Deux modifications chimiques des protéines (l’acylation et la succinylation) ont été étudiées dans le but de modifier la solubilité de la protéine de soja. Ces modifications ont été effectuées dans le respect des principes de la Chimie Verte, notamment en absence de solvant organique. Les microcapsules obtenues par atomisation ont été caractérisées en termes de taux et efficacité d'encapsulation, morphologie et distribution de tailles des particules, état physique du PA encapsulé et capacité de libération en milieu gastrique et intestinal simulé. Les résultats obtenus ont permis de valider l’intérêt des modifications chimiques de la protéine de soja pour moduler les cinétiques de libération d’actif. Les modifications chimiques sont apparues particulièrement adaptées pour l’encapsulation de principes actifs hydrophobes, et ont permis de l’obtention de cinétiques de libération d’ibuprofène ralenties à pH acide (gastrique). La dernière partie de ce travail a permis de valider cette dernière hypothèse par la réalisation de formes gastro-résistantes sur le modèle des comprimés MUPS (multiple unit pellet system). Les résultats de ce travail exploratoire démontrent que les protéines de soja, associées à un procédé de mise en forme multi-particulaire couplé à de la compression directe, peuvent constituer une alternative biosourcée, respectueuse de l’environnement (manipulation en solvant aqueux, temps de séchage et étapes de compression réduits) et sûre à l’enrobage utilisé dans les formes gastro-résistantes traditionnelles. / In the pharmaceutical field, the oral route remains the preferred route of administration because it is simpler and better accepted by patients. However, this mode of administration is problematic for many active pharmaceutical ingredients (API) with low solubility, low permeability and/or instability in the gastrointestinal environment. Their microencapsulation in polymeric matrices can make them able to respond to these factors, especially if the microparticles generated resist the environments encountered during the gastrointestinal tract and then play a protective role, both for the API and for the mucous membranes encountered. The search for new excipients, from agroresources such as natural polymers, is booming. Vegetable proteins, thanks to their functional properties such as good solubility, relatively low viscosity, and emulsifying and film-forming properties, are preferred candidates. In addition, the great diversity of their functional groups makes it possible to envisage various chemical or enzymatic modifications. The aim of this work was to study the interest of soy protein as a coating material for API intended for the oral route, and more particularly as a candidate for the development of gastro-resistant forms. A soy protein isolate (SPI) was used as a coating material and the atomization as a process. Ibuprofen, a nonsteroidal anti-inflammatory drug, was chosen as a model molecule because of its low solubility requiring an improvement in its bioavailability, and its gastric side effects requiring an enteric shaping. Two chemical modifications of proteins (acylation and succinylation) have been studied in order to modify the solubility of the soy protein. These modifications were carried out in accordance with the principles of Green Chemistry, especially in the absence of organic solvent. The microcapsules obtained by spray-drying were characterized in terms of rate and encapsulation efficiency, morphology and size distribution of the particles, physical state of the encapsulated API and capacity of release in simulated gastric and intestinal medium. The results obtained validated the interest of the chemical modifications of the soy protein to modulate the release kinetics of API. The chemical modifications appeared particularly suitable for the encapsulation of hydrophobic active ingredients, and allowed to obtain ibuprofen release kinetics decreased to acidic pH (gastric). The last part of this work allowed to validate this last hypothesis by the realization of gastro-resistant forms on the model of MUPS tablets (multiple unit pellet system). The results of this exploratory work demonstrate that soy protein, combined with a multiparticle shaping process coupled with direct compression, can be a biosourced, environmentally friendly alternative (aqueous solvent handling, drying and compression steps reduced) and confident to the coating used in traditional gastroresistant forms.

No description available.

Background: Tissue factor (TF) is a 47 kDa transmembrane glycoprotein known as the main initiator of blood coagulation. TF is over-expressed on many malignant cells and apart from increasing the risk of thrombosis, the presence of TF/FVIIa also promotes the progression of cancer and metastasis by intracellular signaling. TF expressing microparticles (MP) are, moreover, often found in the circulation of cancer patients. Aim: The aim of this thesis was to study different aspects of TF activity, e.g. the importance of procoagulant MP and TF-induced intracellular signaling pathways, with focus on cell migration (chemotaxis) and apoptosis. Results: The TF signaling complexes were shown to prevent apoptosis induced by serum starvation and TRAIL in cancer cells by reduced activation of caspase-8 in a PI3k/AKT-dependent manner. FVIIa also decreased transcription of pro-apoptotic genes in cancer cells treated with TRAIL. Simvastatin triggered apoptosis by transcriptional reduction of BCL-2 due to cytosolic retention of NFκB. Simvastatin also inactivated the PI3k/AKT pathway and reduced the production of the MP-like prostasomes which, respectively, impaired the anti-apoptotic signaling by TF and reduced the procoagulant activity in the vicinity of prostate cancer cells. Intracellular events conducted by the TF/FVIIa complex selectively enhanced PDGF-BB induced chemotaxis which was partly explained by the TF/FVIIa-induced transactivation of the PDGFβ-receptor. This was dependent on Src-family members and engagement of PAR2. Conclusions: The results presented in this thesis extend the current knowledge of TF-mediated signaling. We report the TF complexes to govern the extrinsic pathway of apoptosis, present data on FVIIa-dependent regulation of apoptosis-related genes, and exclude known surface proteins as transmitters of the anti-apoptotic signals. We moreover describe TF/FVIIa to transactivate the PDGFβ-receptor and play a decisive role in the potentiated chemotaxis toward PDGF-BB in a number of cell types. Finally, we explain the mechanism behind simvastatin-induced apoptosis in cancer cells and how statins interfere with TF-dependent signaling and coagulation.

Le seul traitement actuellement disponible pour les accidents vasculaires cérébraux d’origine ischémique est la thrombolyse par l’activateur tissulaire du plasminogène recombinant (rt-PA). Cependant, l’efficacité du rt-PA est souvent partielle ou absente, et des phénomènes de réocclusion du vaisseau peuvent être observés. Par ailleurs, l’administration de rt-PA est associée à un risque hémorragique. Il apparaît donc indispensable de rechercher les mécanismes à l’origine de la toxicité vasculaire du rt-PA, afin de pouvoir développer des stratégies capables de protéger le lit vasculaire. Parmi ces stratégies, notre équipe a montré dans des modèles expérimentaux que l’inhibition d’une enzyme nucléaire, la poly(ADP-ribose) polymérase ou PARP, permet de protéger la barrière hémato-encéphalique, de réduire les hémorragies et d’améliorer la reperfusion cérébrale suite à l’administration post-ischémique de rt-PA. Dans ce contexte, mon travail a consisté à étudier les mécanismes impliqués dans les altérations vasculaires associées à l’administration de rt-PA à la suite de l’ischémie. Mes travaux de recherche ont comporté un volet in vivo et un volet in vitro. Les études réalisées in vivo ont été menées dans un modèle murin d’ischémie cérébrale thrombo-embolique. Nos résultats indiquent que ni l’ischémie, ni le rt-PA, ni l’association au rt-PA d’un puissant inhibiteur de PARP, le PJ34, ne modifient à 24 heures la présence de dépôts de fibrine, marqueur d’hypoperfusion et de réocclusion. Nous nous sommes ensuite intéressés à deux marqueurs endothéliaux d’inflammation : VCAM-1 et ICAM-1, et avons montré que leur expression, qui augmente 24 heures après l’ischémie, n’est pas modifiée par le rt-PA. Enfin, l’association du PJ34 au rt-PA réduit significativement l’expression post-ischémique de VCAM-1, ce qui suggère le rôle de la PARP dans l’expression de cette molécule d’adhésion. La seconde partie de mon travail a été réalisée in vitro sur une lignée de cellules endothéliales cérébrales murines (bEnd.3). Le rt-PA est à l’origine de changements caractéristiques au niveau de l’organisation et de la morphologie de ces cellules. Ces changements ne sont pourtant associés ni à une dégradation de l’expression des molécules de jonctions inter-endothéliales (occludine, VE-cadhérine), ni à une augmentation de l’expression des marqueurs endothéliaux pro-inflammatoires (VCAM-1, ICAM-1). Nous nous sommes également intéressés à d’autres marqueurs de dysfonction endothéliale, les microparticules endothéliales (MPE). Nos résultats montrent que le rt-PA est à l’origine d’une augmentation importante de la libération des MPE. L’utilisation d’un inhibiteur de la protéine p38, le SB203580, et d’un inhibiteur de PARP, le PJ34, permet de réduire cette augmentation, ce qui suggère que p38 et la PARP pourraient être impliquées dans la production de MPE induite par le rt-PA. En conclusion, l’ensemble de ce travail contribue à préciser les effets vasculaires du rt-PA. Parmi ces effets, la mise en évidence de la production de MPE, via la PARP, est particulièrement novatrice. / Thrombolysis with recombinant tissue plasminogen activator (rt-PA) is currently the only approved pharmacological strategy for acute ischemic stroke. However, the efficacy of rt-PA is rarely complete, and arterial reocclusion can be observed. Furthermore, administration of rt-PA increases the risk of hemorrhagic transformations. Therefore, it is essential to seek mechanisms underlying the vascular toxicity of rt-PA in order to develop strategies protecting the vascular bed. Among these strategies, our laboratory has previously shown that inhibition of poly (ADP-ribose) polymerase (PARP), a nuclear enzyme, protects the blood-brain barrier, reduces hemorrhagic transformations and improves cerebral reperfusion following the post-ischemic administration of rt-PA. In this context, the aim of the present work was to establish the post-ischemic mechanisms of rt-PA-induced vascular alterations. The research was divided into (1) in vivo experiments and (2) in vitro studies to examine the effect of rt-PA on the endothelium. The in vivo studies were performed in a mouse model of thrombo-embolic stroke induced by thrombin injection in the middle cerebral artery. Our results showed that neither ischemia, nor rt-PA, nor the association to rt-PA of the potent inhibitor of PARP PJ34 alter cerebral fibrin deposits, a marker of hypoperfusion and reocclusion, at 24 hours after ischemia. We then evaluated the expression of two endothelial markers of inflammation : VCAM-1 (vascular cell adhesion molecule-1) and ICAM-1 (intercellular adhesion molecule-1). Our results showed that their expressions increase 24 hours after ischemia and are not modified by rt-PA. Finally, the association of PJ34 to rt-PA significantly reduced the post-ischemic expression of VCAM-1, suggesting a role for PARP in the expression of this adhesion molecule. The second part of my work was carried out in vitro in cultures of mouse brain-derived endothelial cells bEnd.3. In the presence of rt-PA, the organization and the morphology of the endothelial cells radically changed. However, these changes were associated neither to a degradation of endothelial junction proteins (occludin, VE-cadherin (vascular endothelial-cadherin)), nor to an increase in the expression of pro-inflammatory endothelial markers (VCAM-1, ICAM-1). We were also interested in a recently identified marker of endothelial dysfunction : endothelial microparticles (EMP). Our results showed that rt-PA induces a significant increase in the EMP released by bEnd.3 cells. The use of a p38 inhibitor, SB203580, and the PARP inhibitor, PJ34, reduced this increase, suggesting that p38 and PARP could be involved in the EMP production induced by rt-PA. In conclusion, this work helps to clarify the vascular effects of rt-PA. Among these effects, the highlight of EMP production, through PARP pathway, is particularly original.