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Mechanically cartilage-mimicking poly(PCL-PTHF urethane)/collagen nanofibers induce chondrogenesis by blocking NF–kappa B signaling pathway

Biomaterials - Sun, 2018-06-24 02:17
Publication date: September 2018
Source:Biomaterials, Volume 178

Author(s): Tongmeng Jiang, Dan Kai, Sijia Liu, Xianyuan Huang, Shujun Heng, Jinmin Zhao, Benjamin Qi Yu Chan, Xian Jun Loh, Ye Zhu, Chuanbin Mao, Li Zheng

Cartilage cannot self-repair and thus regeneration is a promising approach to its repair. Here we developed new electrospun nanofibers, made of poly (ε-caprolactone)/polytetrahydrofuran (PCL-PTHF urethane) and collagen I from calf skin (termed PC), to trigger the chondrogenic differentiation of mesenchymal stem cells (MSCs) and the cartilage regeneration in vivo. We found that the PC nanofibers had a modulus (4.3 Mpa) lower than the PCL-PTHF urethane nanofibers without collagen I from calf skin (termed P) (6.8 Mpa) although both values are within the range of the modulus of natural cartilage (1–10 MPa). Both P and PC nanofibers did not show obvious difference in the morphology and size. Surprisingly, in the absence of the additional chondrogenesis inducers, the softer PC nanofibers could induce the chondrogenic differentiation in vitro and cartilage regeneration in vivo more efficiently than the stiffer P nanofibers. Using mRNA-sequence analysis, we found that the PC nanofibers outperformed P nanofibers in inducing chondrogenesis by specifically blocking the NF–kappa B signaling pathway to suppress inflammation. Our work shows that the PC nanofibers can serve as building blocks of new scaffolds for cartilage regeneration and provides new insights on the effect of the mechanical properties of the nanofibers on the cartilage regeneration.





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Poly(2-oxazoline)s based biomaterials: A comprehensive and critical update

Biomaterials - Sun, 2018-06-24 02:17
Publication date: September 2018
Source:Biomaterials, Volume 178

Author(s): Thomas Lorson, Michael M. Lübtow, Erik Wegener, Malik S. Haider, Solomiia Borova, Daniel Nahm, Rainer Jordan, Marina Sokolski-Papkov, Alexander V. Kabanov, Robert Luxenhofer

Poly(2-oxazoline)s have been investigated for decades as biomaterials. Pioneering early work suggested that hydrophilic poly(2-oxazoline)s are comparable to poly(ethylene glycol) regarding their potential as biomaterials, but the ready commercial availability of the latter has led to its meteoric rise to become the gold standard of hydrophilic synthetic biomaterials. In contrast, poly(2-oxazoline)s almost fell into oblivion. However, in the last decade, this family of polymers has gained much more interest in general and as biomaterials in particular. The rich chemistry and comparably straightforward synthesis of poly(2-oxazoline)s gives many opportunities for tailoring the properties of the resulting biomaterials, allowing the chemist to explore new conjugation chemistry, and to fine-tune the molar mass, hydrophilic-lipophilic balance as well as architecture. Thus, the wide range of demands for various applications of biomaterials can be suitably addressed. This review aims to give a comprehensive and critical update of the development of poly(2-oxazoline) based biomaterials, focusing on the last 5 years, which have seen an explosive increase of interest. We believe that the research regarding this diverse family of polymers will remain strong and will keep growing, in particular after the promising first-in-human studies of a poly(2-oxazoline) drug conjugate. This review aims at researchers and students new to this polymer family and seasoned poly(2-oxazoline) experts alike and attempts to showcase how the chemical diversity of poly(2-oxazoline)s allows a relatively facile and broad access to biomaterials of all kinds.





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Biodegradable PEG-poly(ω-pentadecalactone-co-p-dioxanone) nanoparticles for enhanced and sustained drug delivery to treat brain tumors

Biomaterials - Fri, 2018-06-22 08:17
Publication date: September 2018
Source:Biomaterials, Volume 178

Author(s): Evan M. Chen, Amanda R. Quijano, Young-Eun Seo, Christopher Jackson, Alexander D. Josowitz, Seth Noorbakhsh, Andrea Merlettini, Ranjini K. Sundaram, Maria Letizia Focarete, Zhaozhong Jiang, Ranjit S. Bindra, W. Mark Saltzman

Intracranial delivery of therapeutic agents is limited by penetration beyond the blood-brain barrier (BBB) and rapid metabolism of the drugs that are delivered. Convection-enhanced delivery (CED) of drug-loaded nanoparticles (NPs) provides for local administration, control of distribution, and sustained drug release. While some investigators have shown that repeated CED procedures are possible, longer periods of sustained release could eliminate the need for repeated infusions, which would enhance safety and translatability of the approach. Here, we demonstrate that nanoparticles formed from poly(ethylene glycol)-poly(ω-pentadecalactone-co-p-dioxanone) block copolymers [PEG-poly(PDL-co-DO)] are highly efficient nanocarriers that provide long-term release: small nanoparticles (less than 100 nm in diameter) continuously released a radiosensitizer (VE822) over a period of several weeks in vitro, provided widespread intracranial drug distribution during CED, and yielded significant drug retention within the brain for over 1 week. One advantage of PEG-poly(PDL-co-DO) nanoparticles is that hydrophobicity can be tuned by adjusting the ratio of hydrophobic PDL to hydrophilic DO monomers, thus making it possible to achieve a wide range of drug release rates and drug distribution profiles. When administered by CED to rats with intracranial RG2 tumors, and combined with a 5-day course of fractionated radiation therapy, VE822-loaded PEG-poly(PDL-co-DO) NPs significantly prolonged survival when compared to free VE822. Thus, PEG-poly(PDL-co-DO) NPs represent a new type of versatile nanocarrier system with potential for sustained intracranial delivery of therapeutic agents to treat brain tumors.





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Editorial Board

Biomaterials - Fri, 2018-06-22 08:17
Publication date: September 2018
Source:Biomaterials, Volume 177









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[ASAP] Phase Transition of Graphene-Templated Vertical Zinc Phthalocyanine Nanopillars

Journal of the American Chemical SocietyDOI: 10.1021/jacs.8b03078
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[ASAP] Direct Access to Versatile Electrophiles via Catalytic Oxidative Cyanation of Alkenes

Journal of the American Chemical SocietyDOI: 10.1021/jacs.8b03704
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[ASAP] Integrating Organic Lewis Acid and Redox Catalysis: The Phenalenyl Cation in Dual Role

Journal of the American Chemical SocietyDOI: 10.1021/jacs.8b04786
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[ASAP] A Highly-Reduced Cobalt Terminal Carbyne: Divergent Metal- and a-Carbon-Centered Reactivity

Journal of the American Chemical SocietyDOI: 10.1021/jacs.8b05019
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[ASAP] Asymmetric Photocatalytic C–H Functionalization of Toluene and Derivatives

Journal of the American Chemical SocietyDOI: 10.1021/jacs.8b05240
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[ASAP] Computational Design To Reduce Conformational Flexibility and Aggregation Rates of an Antibody Fab Fragment

Molecular Pharmaceutics - Thu, 2018-06-21 21:00

Molecular PharmaceuticsDOI: 10.1021/acs.molpharmaceut.8b00186
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[ASAP] Morphology-Controlled Synthesis of Rhodium Nanoparticles for Cancer Phototherapy

ACS Nano - Thu, 2018-06-21 21:00

ACS NanoDOI: 10.1021/acsnano.8b02698
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[ASAP] Palladium-Catalyzed Regiocontrollable Reductive Heck Reaction of Unactivated Aliphatic Alkenes

Journal of the American Chemical SocietyDOI: 10.1021/jacs.8b03619
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