- Interaction of acyclovir and its squalenoyl-acyclovir prodrug with DMPC in monolayers at the air/water interface
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Acyclovir has been conjugated to the acyclic isoprenoid chain of squalene to form the squalenoyl-acyclovir prodrug. Its interaction with biomembrane models constituted by dimyristoylphosphatidylcholine (DMPC) monolayers has been studied by employing the Langmuir-Blodgett technique. The aim of the work was to gain information on the interaction of these compounds with phospholipid membranes. DMPC/acyclovir or squalenoyl-acyclovir prodrug mixed monolayers have been prepared at increasing molar fractions of the compound and the isotherm mean molecular area/surface pressure has been registered at 10 and 37 °C. Results reveal that the squalenoyl moiety enhances the affinity of acyclovir for the biomembrane model.
- Sarpietro, Maria Grazia,Rocco, Flavio,Micieli, Dorotea,Ottimo, Sara,Ceruti, Maurizio,Castelli, Francesco
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- Preactivated oxazaphosphorines designed for isophosphoramide mustard delivery as bulk form or nanoassemblies: Synthesis and proof of concept
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Oxazaphosphorines are alkylating agents used in routine clinical practices for treatment of cancer for many years. They are antitumor prodrugs that require cytochrome P450 bioactivation leading to 4-hydroxy derivatives. In the case of ifosfamide (IFO), the bioactivation produces two toxic metabolites: acrolein, a urotoxic compound, concomitantly generated with the isophosphoramide mustard; and chloroacetaldehyde, a neurotoxic and nephrotoxic compound, arising from the oxidation of the side chains. To improve the therapeutic index of IFO, we have designed preactivated IFO derivatives with the covalent binding of several O- and S-alkyl moieties including polyisoprenoid groups at the C-4 position of the oxazaphosphorine ring to avoid cytochrome bioactivation favoring the release of the active entity and limiting the chloroacetaldehyde release. Thanks to the grafted terpene moieties, some of these new conjugates demonstrated spontaneous self-assembling properties into nanoassemblies when dispersed in water. The cytotoxic activities on a panel of human tumor cell lines of these novel oxazaphosphorines, in bulk form or as nanoassemblies, and the release of 4-hydroxy-IFO from these preactivated IFO analogues in plasma are reported.
- Skarbek, Charles,Lesueur, Lea L.,Chapuis, Hubert,Deroussent, Alain,Piochedurieu, Catherine,Daville, Aurore,Caron, Joachim,Rivard, Michael,Martens, Thierry,Bertrand, Jean-Rémi,Le Cam, Eric,Vassal, Gilles,Couvreur, Patrick,Desmaele, Didier,Paci, Angelo
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- Inulin-based polymer coated SPIONs as potential drug delivery systems for targeted cancer therapy
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This paper deal with the synthesis and characterization of PEGylated squalene-grafted-inulin amphiphile capable of self-assembling and self-organizing into nanocarriers once placed in aqueous media. It was exploited as coating agent for obtaining doxorubicin loaded superparamagnetic iron oxide nanoparticles (SPIONs) endowed with stealth like behavior and excellent physicochemical stability. Inulin was firstly modified in the side chain with primary amine groups, followed in turn by conjugation with squalenoyl derivatives through common amidic coupling agents and PEGylation by imine linkage. Polymer coated SPIONs were so obtained by spontaneous self-assembling of inulin copolymer onto magnetite surface involving hydrophobic-hydrophobic interactions between the metallic core and the squalene moieties. The system was characterized in terms of hydrodynamic radius, zeta potential, shape and drug loading capacity. On the whole, the stealth-like shell stabilized the suspension in aqueous media, though allowing the release of the doxorubicin loaded in therapeutic range. The cytotoxicity profile on cancer (HCT116) cell line and in vitro drug uptake were evaluated both with and without an external magnetic field used as targeting agent and uptake promoter, displaying that magnetic targeting implies advantageous therapeutic effects, that is amplified drug uptake and increased anticancer activity throughout the tumor mass.
- Scialabba,Licciardi,Mauro,Rocco,Ceruti,Giammona
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- Synthesis of n-squalenoyl cytarabine and evaluation of its affinity with phospholipid bilayers and monolayers
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Cytarabine (1-β-d-arabinofuranosylcytosine, Ara-C), a pyrimidine nucleoside analogue, is an attractive therapeutic agent for the treatment of both acute and chronic myeloblastic leukemias. 1,1′,2-tris-nor-Squalene acid (squaleneCOOH) has been conjugated to cytarabine with the formation of the squalenoyl-cytarabine prodrug, in order to improve the drug lipophilicity and, consequently, the affinity towards the environment of biological membranes, as well as of lipophilic carriers. The interaction of cytarabine and its prodrug with dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles and monolayers has been studied by the differential scanning calorimetry and the Langmuir-Blodgett techniques. The interaction has been evaluated considering the effect of the compounds on the DMPC MLV and monolayers behaviour. The aim was to have information on the interaction of the drug and the prodrug with the biological membranes and on the possibility to use liposomes as carriers for the prodrug. The results showed an improved affinity of the prodrug with MLV and monolayers with respect to the free drug.
- Sarpietro, Maria Grazia,Ottimo, Sara,Giuffrida, Maria Chiara,Rocco, Flavio,Ceruti, Maurizio,Castelli, Francesco
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- Design and characterization of Squalene-Gusperimus nanoparticles for modulation of innate immunity
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Immunosuppressive drugs are widely used for the treatment of autoimmune diseases and to prevent rejection in organ transplantation. Gusperimus is a relatively safe immunosuppressive drug with low cytotoxicity and reversible side effects. It is highly hydrophilic and unstable. Therefore, it requires administration in high doses which increases its side effects. To overcome this, here we encapsulated gusperimus as squalene-gusperimus nanoparticles (Sq-GusNPs). These nanoparticles (NPs) were obtained from nanoassembly of the squalene gusperimus (Sq-Gus) bioconjugate in water, which was synthesized starting from squalene. The size, charge, and dispersity of the Sq-GusNPs were optimized using the response surface methodology (RSM). The colloidal stability of the Sq-GusNPs was tested using an experimental block design at different storage temperatures after preparing them at different pH conditions. Sq-GusNPs showed to be colloidally stable, non-cytotoxic, readily taken up by cells, and with an anti-inflammatory effect sustained over time. We demonstrate that gusperimus was stabilized through its conjugation with squalene and subsequent formation of NPs allowing its controlled release. Overall, the Sq-GusNPs have the potential to be used as an alternative in approaches for the treatment of different pathologies where a controlled release of gusperimus could be required.
- Navarro Chica, Carlos E.,de Haan, Bart J.,Faas,Smink, Alexandra M.,Sierra, Ligia,de Vos, Paul,López, Betty L.
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- OLIGONUCLEOTIDE COMPOSITIONS AND METHODS THEREOF
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Among other things, the present disclosure relates to designed oligonucleotides, compositions, and methods thereof. In some embodiments, provided oligonucleotide compositions provide altered splicing of a transcript. In some embodiments, provided oligonucleotide compositions have low toxicity. In some embodiments, provided oligonucleotide compositions provide improved protein binding profiles. In some embodiments, provided oligonucleotide compositions have improved delivery. In some embodiments, provided oligonucleotide compositions have improved uptake. In some embodiments, the present disclosure provides methods for treatment of diseases using provided oligonucleotide compositions.
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- OLIGONUCLEOTIDES, COMPOSITIONS AND METHODS THEREOF
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The present disclosure pertains to the recognition that immune responses mediated by CpG oligonucleotides can be affected by the stereochemistry of modified internucleotidic linkages such as phosphorothioates. In some embodiments, the present disclosure relates to chirally controlled CpG oligonucleotide compositions comprising CpG oligonucleotides comprising multiple modified internucleotidic linkages such as phosphorothioate linkages, wherein the oligonucleotides comprise one or more CpG region motifs having defined stereochemistry patterns of chiral internucleotidic linkages. In some embodiments, CpG oligonucleotides comprising one or more CpG region motifs are capable of agonizing an immune response. In some embodiments, CpG oligonucleotides comprising one or more CpG region motifs are antagonistic. Methods for making and using chirally controlled CpG oligonucleotide compositions are also described. In some embodiments, no immune modulation is desired, and the present disclosure provides methods of identifying chirally controlled oligonucleotide compositions which have decreased immune modulation.
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- VITAMIN C COMPLEXES
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A complex formed of at least one molecule of 5-(1,2-dihydroxy-ethyl)-3,4-dihydroxy-5H-furan-2-one or a derivative covalently bonded with at least one hydrocarbon radical with formula (A) as follows: wherein: ?-m 1=1, 2, 3, 4, 5 or 6; ?-m 2=0, 1, 2, 3, 4, 5 or 6; and represents the site of the bond with the molecule of 5-(1,2-dihydroxy-ethyl)-3,4-dihydroxy-5H-furan-2-one or derivative. Formula (I)
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Paragraph 0184-0190
(2015/02/25)
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- NANOPARTICLES OF BETA-LACTAM DERIVATIVES
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The present invention relates to a complex made up of at least one beta-lactam molecule covalently bonded to at least one hydrocarbon radical including at least 18 carbon atoms and containing at least one unit of 2-methyl-buta-2-ene, to nanoparticles of s
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Page/Page column 9
(2011/11/12)
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- Methodology for the preparation of pure recombinant S. cerevisiae lanosterol synthase using a baculovirus expression system. Evidence that oxirane cleavage and A-ring formation are concerted in the biosynthesis of lanosterol from 2,3-oxidosqualene
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Lanosterol synthase [(S)-2,3-epoxysqualene mutase (cyclizing, lanosterol forming), EC 5.4.99.7], the enzyme from Saccharomyces cerevisiae which catalyzes the complex cyclization/rearrangement step in sterol biosynthesis, was overexpressed in baculovirus-infected cells and purified to homogeneity in three steps. Using pure enzyme the kinetics of cyclization were determined using Michaelis-Menten analysis for 2,3-oxidosqualene (1) and two analogs in which the C-6 methyl was replaced by H (3) or Cl (4). The measured V(max)/K(M) ratios for 1, 3, and 4 were found to be 138, 9.4, and 21.9, respectively, a clear indication that oxirane cleavage and cyclization to form the A-ring are concerted, since the nucleophilicity of the proximate double bond influences the rate of oxirane cleavage. No catalytic metal ions could be detected in purified lanosterol synthase by atomic absorption analysis. Site-directed mutagenesis studies of each of the six strongly conserved aspartic acid residues (D → N mutation) and each of the nine conserved glutamic acid residues (E → Q) revealed that only one, D456, is essential lor catalytic function of the enzyme. The essential D456 residue is a likely candidate for electrophilic (specifically protic) activation of the oxirane function.
- Corey,Cheng, Hengmiao,Baker, C. Hunter,Matsuda, Seiichi P. T.,Li, Ding,Song, Xuelei
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p. 1277 - 1288
(2007/10/03)
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