- A new biomimetic route to engineer enzymatically active mechano-responsive materials
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Using modified β-galactosidase covalently linked to cross-linked polyelectrolyte multilayers (PEM), catalytically active materials have been designed. Their enzymatic activity can be modulated, partially in a reversible way, simply by stretching. This strategy, based on enzyme conformational changes, constitutes a new tool for the development of biocatalytic mechano-responsive materials.
- Rios, César,Longo, Johan,Zahouani, Sarah,Garnier, Tony,Vogt, Cédric,Reisch, Andreas,Senger, Bernard,Boulmedais, Fouzia,Hemmerlé, Joseph,Benmlih, Karim,Frisch, Beno?t,Schaaf, Pierre,Jierry, Lo?c,Lavalle, Philippe
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- Enhanced Reactive Oxygen Species Generation by Mitochondria Targeting of Anticancer Drug to Overcome Tumor Multidrug Resistance
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As a major clinical tumor chemotherapeutic burden, multidrug resistance (MDR) is often a result of up-regulation of P-glycoprotein (P-gp), which strongly enhances anticancer drug efflux. The excess mitochondrial reactive oxygen species (ROS) could not only inhibit the function of P-gp through insufficient adenosine triphosphate supply but also cause apoptosis in MDR cells. Here, we designed a mitochondria targeting nanoparticulate system (GNPs-P-Dox-GA) for overcoming MDR through enhanced ROS generation, where increased cellular uptake as well as mitochondria accumulation were both realized by glycyrrhetinic acid (GA). First, doxorubicin was conjugated with GA (GA-Dox) and then grafted onto a N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer backbone via hydrazone bond (P-Dox-GA). The obtained P-Dox-GA was subsequently attached to the surface of gelatin nanoparticles (GNPs). As gelatin is a substrate of tumor extracellular metal matrix protease-2 (MMP2), GNPs-P-Dox-GA nanoparticles could be degraded and release small size P-Dox-GA to facilitate tumor tissue penetration. After P-Dox-GA internalized by tumor cells under GA mediation, Dox-GA detached from HPMA copolymer through hydrolysis of hydrazone bond and then efficiently delivered to mitochondria. Compared to non-GA modified carriers, GNPs-P-Dox-GA exhibited increased cellular uptake nearly 4-fold and mitochondria distribution 8.8-fold, and increased ROS production level nearly 3-fold, significantly decreased efflux rate (55% compared with Dox group) in drug resistant HepG2/ADR cells, and then led to improved in vitro antitumor efficiency in HepG2/ADR cells (IC50 only 19.5% of unmodified ones) as well as exciting in vivo antitumor efficiency on HepG2/ADR heterotopic tumor nude mice (1.75-fold higher tumor growth inhibition rate than free drug).
- Liu, Yuanyuan,Zhou, Zhou,Lin, Xi,Xiong, Xiaofeng,Zhou, Rui,Zhou, Minglu,Huang, Yuan
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- Nanoscale protein pores modified with PAMAM dendrimers
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We describe nanoscale protein pores modified with a single hyperbranched dendrimer molecule inside the channel lumen. Sulfhydryl-reactive polyamido amine (PAMAM) dendrimers of generations 2, 3 and 5 were synthesized, chemically characterized, and reacted with engineered cysteine residues in the transmembrane pore α-hemolysin. Successful coupling was monitored using an electrophoretic mobility shift assay. The results indicate that G2 and G3 but not G5 dendrimers permeated through the 2.9 nm cis entrance to couple inside the pore. The defined molecular weight cutoff for the passage of hyperbranched PAMAM polymers is in contrast to the less restricted accessibility of flexible linear poly(ethylene glycol) polymers of comparable hydrodynamic volume. Their higher compactness makes sulfhydryl-reactive PAMAM dendrimers promising research reagents to probe the structure of porous membrane proteins with wide internal diameters. The conductance properties of PAMAM-modified proteins pores were characterized with single-channel current recordings. A G3 dendrimer molecule in the channel lumen reduced the ionic current by 45%, indicating that the hyperbranched and positively charged polymer blocked the passage of ions through the pore. In line with expectations, a smaller and less dense G2 dendrimer led to a less pronounced current reduction of 25%. Comparisons to recordings of PEG-modified pores revealed striking dissimilarities, suggesting that differences in the structural dynamics of flexible linear polymers vs compact dendrimers can be observed at the single-molecule level. Current recordings also revealed that dendrimers functioned as ion-selectivity filters and molecular sieves for the controlled passage of molecules. The alteration of pore properties with charged and hyperbranched dendrimers is a new approach and might be extended to inorganic nanopores with applications in sensing and separation technology.
- Martin, Hugh,Kinns, Helen,Mitchell, Nick,Astier, Yann,Madathil, Rethi,Howorka, Stefan
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- NUCLEOSIDE ANALOGUE, PREPARATION METHOD AND APPLICATION
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Nucleoside or nucleotide analog compounds having the structure shown below, a method for preparing them, and applications in nucleic acid sequencing are disclosed. The compounds have formula (I): wherein L1, L2, and L3 are each independently a covalent bond or a covalently linked group; B is a base or a base derivative selected from purines, pyrimidines, or analogs thereof; R1 is —OH, a phosphate group, or a nucleotide; R2 as H or a cleavable group; R3 is a detectable group or a targeting group; R5 is an inhibitory group; R4 is H, —NH2, or —OR6, wherein R6 is H or a cleavable group; and C is a cleavable group or a cleavable bond.
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Paragraph 0157; 0158; 0193
(2020/09/22)
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- With deficiency oxygen target tropism of polyvalent ligand drug conjugates (by machine translation)
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The invention discloses a deficiency oxygen target tropism of polyvalent ligand drug conjugates, through containing mercapto homeotropic deficiency oxygen target drug derivative molecule ligand and with the maleimide derivatized dextran of connected, can realize the corresponding drug molecules on tumor tissues to [...], has good anti-tumor activity. . (by machine translation)
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Paragraph 0074; 0076; 0079; 0080
(2019/06/05)
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- Modulated Fragmentation of Proapoptotic Peptide Nanoparticles Regulates Cytotoxicity
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Peptides perform a diverse range of physiologically important functions. The formulation of nanoparticles directly from functional peptides would therefore offer a versatile and robust platform to produce highly functional therapeutics. Herein, we engineered proapoptotic peptide nanoparticles from mitochondria-disrupting KLAK peptides using a template-assisted approach. The nanoparticles were designed to disassemble into free native peptides via the traceless cleavage of disulfide-based cross-linkers. Furthermore, the cytotoxicity of the nanoparticles was tuned by controlling the kinetics of disulfide bond cleavage, and the rate of regeneration of the native peptide from the precursor species. In addition, a small molecule drug (i.e., doxorubicin hydrochloride) was loaded into the nanoparticles to confer synergistic cytotoxic activity, further highlighting the potential application of KLAK particles in therapeutic delivery.
- Suma, Tomoya,Cui, Jiwei,Müllner, Markus,Fu, Shiwei,Tran, Jenny,Noi, Ka Fung,Ju, Yi,Caruso, Frank
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supporting information
p. 4009 - 4018
(2017/03/31)
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- A Programmable Signaling Molecular Recognition Nanocavity Prepared by Molecular Imprinting and Post-Imprinting Modifications
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Inspired by biosystems, a process is proposed for preparing next-generation artificial polymer receptors with molecular recognition abilities capable of programmable site-directed modification following construction of nanocavities to provide multi-functionality. The proposed strategy involves strictly regulated multi-step chemical modifications: 1) fabrication of scaffolds by molecular imprinting for use as molecular recognition fields possessing reactive sites for further modifications at pre-determined positions, and 2) conjugation of appropriate functional groups with the reactive sites by post-imprinting modifications to develop programmed functionalizations designed prior to polymerization, allowing independent introduction of multiple functional groups. The proposed strategy holds promise as a reliable, affordable, and versatile approach, facilitating the emergence of polymer-based artificial antibodies bearing desirable functions that are beyond those of natural antibodies.
- Horikawa, Ryo,Sunayama, Hirobumi,Kitayama, Yukiya,Takano, Eri,Takeuchi, Toshifumi
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supporting information
p. 13023 - 13027
(2016/10/30)
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- Mass spectrometry-based assay for the rapid detection of thiol-containing natural products
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Natural products are privileged scaffolds due to their high propensity to possess bioactivity. To expedite discovery of thiol-containing compounds, we devised a selective solid-supported reagent for their immobilization, followed by cleavage of a photocleavable linker to yield stable natural product conjugates for direct detection by mass spectrometry. Importantly, the natural products can also be tracelessly released to yield the native structures for chemical and biological evaluation.
- Capehart, Stacy L.,Carlson, Erin E.
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supporting information
p. 13229 - 13232
(2016/11/17)
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- CONVENIENT METHOD FOR THE PREPARATION OF 3-(2-PYRIDYL DITHIO) PROPIONIC ACID N-HYDROXY SUCCINIMID ESTER
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A new efficient and simple method for the preparation of 3-(2-pyridyl dithio) propionic acid N-hydroxy succinimid ester using diethyl azo dicarboxylate, is described.
- Loccufier, J.,Schacht, E.
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p. 535 - 540
(2007/10/02)
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- Desmosine derivatives having a disulfide bond and preparation of artificial antigen using the same
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A novel desmosine derivative, which is useful for preparing a desmosine artificial antigen, has an activated, disulfide bond on the side chain at 3 or 5 position of the pyridinium ring. The derivative can combine with a polymer having thiel groups by a disulfide bond to form the effective artificial antigen.
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- Pyridine disulfide compounds
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Novel pyridine compounds having the formula R1 -S-S-A-Z are disclosed, in which formula R1 is 2-pyridyl, 5-nitro-2-pyridyl or 4-pyridyl, A is a hydrocarbon residue having 1-10 carbon atoms and Z is a group STR1 or acid addition salts of the last mentioned group, where n is 2 or 3, R1 has the same significance as R1 above and is equal thereto and R2 is methyl or ethyl. These compounds are particularly useful as bifunctional coupling agents and as thiolating agents.
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