Read by QxMD icon Read


Jacob Witten, Tahoura Samad, Katharina Ribbeck
Binding of small molecules to mucus membranes in the body has an important role in human health, as it can affect the diffusivity and activity of any molecule that acts in a mucosal environment. The binding of drugs, and of toxins and signaling molecules from mucosal pathogens, is of particular clinical interest. Despite the importance of mucus-small molecule binding, there is a lack of data revealing the precise chemical features of small molecules that lead to mucus binding. We developed a novel equilibrium dialysis assay to measure the binding of libraries of small molecules to mucin and other mucus components, substantially increasing the throughput of small molecule binding measurements...
February 19, 2019: Biomacromolecules
Cheng Cao, Jiacheng Zhao, Mingxia Lu, Christopher J Garvey, Martina H Stenzel
Drug delivery carriers are now widely established as they can increase the therapeutic efficiency of drugs. In general, the aim in this field is to create effective carriers that have large amounts of drugs loaded in order to minimize drug carrier material that needs to be disposed of. However, there was little attention so far in the literature on the effect of the amount of loaded drugs on the biological activity. In this paper, we are trying to answer the question how the drug loading content will affect the in vitro activity...
February 15, 2019: Biomacromolecules
Victor V Revin, Nikolay A Pestov, Michael V Shchankin, Vladimir M Mishkin, Vladimir I Platonov, Dmitriy A Uglanov
Aerogels with a density of 4.2-22.8 kg/m3 were obtained from bacterial cellulose synthesized in static and dynamic cultivation conditions on a molasses medium. The strength properties and porous structure of the aerogels strongly depended on their density. With a 22.8 kg/m3 aerogel density, the modulus of elasticity at 80% compression of the sample was 0.1 MPa. The decrease in the density of aerogels led to an increase in the pore sizes ranging from 20 µm to 1000 µm and a decrease in the modulus of elasticity...
February 15, 2019: Biomacromolecules
Akihiro Nishiguchi, Tetsushi Taguchi
An injectable bone may serve as a minimally invasive therapy for large orthopedic defects and osteoporosis and an alternative to allografting and surgical treatment. However, conventional bone substitutes lack the desirable biodegradability, bioresponsibility, and functionality to regulate the bone regeneration process. Here, we report an injectable, bioresponsive bone composed of bisphosphonate-modified nanocellulose (pNC) as a bone substitute for bone regeneration. Composites composed of nano-fibrillated cellulose and β-tricalcium phosphate (β-TCP) mimic bone structures in which apatite reinforces collagen fibrils...
February 15, 2019: Biomacromolecules
Takashi Matsuhira, Keizo Yamamoto, Hiromi Sakai
Hemoglobin (Hb), an oxygen-carrying protein, has an α2 β2 tetrameric structure that dissociates reversibly into two αβ dimers (α2 β2 ⇄ 2αβ). We synthesized a cyclic Hb-ring monomer with two β subunits bound through a 10 kDa polyethylene glycol (PEG) chain. The monomer induced ring-opening polymerization to produce a supramolecular polymer via intersubunit interaction of αβ dimers of an Hb molecule at the PEG terminals. Both the ring-closed monomer and the ring-opened supramolecular polymer were then fixed covalently by intramolecular cross-linking of two β subunits...
February 15, 2019: Biomacromolecules
Jun-Jie Yan, Xin-Yu Wang, Meng-Zhen Wang, Dong-Hui Pan, Run-Lin Yang, Yu-Ping Xu, Li-Zhen Wang, Min Yang
Non-conjugated red fluorescent polymers have been increasingly studied to improve the biocompatibility and penetration depth over conventional fluorescent materials. However, the accessibility of such polymers remains challenging due to the scarcity of non-conjugated fluorophores and lacking relevant mechanism of red-shifted fluorescence. Herein, we discovered that the combination of hydrogen bonding and π-π stacking interactions provides non-conjugated poly(amide-imide) with a large bathochromic shift (> 100 nm) from blue-green fluorescence to red emission...
February 14, 2019: Biomacromolecules
Dominik Weber, Sven Knaack, Kay Hettrich, Mindaugas Andrulis, Frank Momburg, Mandy Quade, Michael Gelinsky, Reinhard Schwartz-Albiez
No abstract text is available yet for this article.
February 13, 2019: Biomacromolecules
Daniel Bermejo-Velasco, Alice Azémar, Oommen P Oommen, Jöns Hilborn, Oommen P Varghese
The disulfide bond plays a crucial role in protein biology and has been exploited by scientists to develop antibody-drug conjugates, sensors, and for the immobilization other biomolecules to materials surfaces. In spite of its versatile use, the disulfide chemistry suffers from some inevitable limitations such as the need for basic conditions (pH > 8.5), strong oxidants, and long reaction times. We demonstrate here that thiol-substrates containing electron-withdrawing groups at the β-position influence the deprotonation of the thiol group, which is the key reaction intermediate in the formation of disulfide bonds...
February 13, 2019: Biomacromolecules
Rahi M Reja, Rajat Patel, Vivek Kumar, Anjali Jha, Hosahudya N Gopi
The ordered supramolecular assemblies of short peptides have been recently gaining momentum due to their wide spread applications in biology and materials sciences. In contrast to the α-peptides, limited success has been achieved from the backbone modified peptides. The proteolytic stability and conformational flexibility of the backbone modified peptides composed of β-, γ- and δ-amino acids can be explored to design ordered supramolecular gels and self-assembled materials. In this article, we are reporting the divergent supramolecular gels from a new class of short hybrid dipeptides composed of conformationally flexible new β(O)-δ5-amino acids...
February 12, 2019: Biomacromolecules
Muneki Oouchi, Jinta Ukawa, Yoshitaka Ishii, Hideaki Maeda
The terminal groups of natural rubber (NR) are widely believed to play a crucial role in defining the excellent mechanical and other physical properties of processed NR products. Despite their presumed importance, the chemical structures of the terminal groups are elusive in widely used NR species with a high degree of polymerization, such as Hevea natural rubber (H-NR). In previous studies, structural analysis by solution NMR has been carried out on the terminal units of NR after chemical treatment involving chemical alterations, such as deproteinization with enzymes and other chemicals...
February 12, 2019: Biomacromolecules
Markus Andersson Trojer, Mats Andersson, Johan Bergenholtz, Paul Gatenholm
A series of thermoresponsive graft copolymers, gelling at physiological conditions in aqueous solution and cell growth media, have been synthesized using quantitative coupling between a small set of amino-functionalized poly(alkylene oxide) copolymers (PAO) and the carboxylate of the biologically important polysaccharides (PSa) carboxymethylcellulose and the less reactive hyaluronate. Quantitative grafting enables the establishment of structure-function relationship which is imperative for controlling the properties of in situ gelling hydrogels...
February 12, 2019: Biomacromolecules
Lucia Lombardi, Yejiao Shi, Annarita Falanga, Emilia Galdiero, Elisabetta de Alteriis, Gianluigi Franci, Igor Chourpa, Helena S Azevedo, Stefania Galdiero
Healthcare-associated infections resulting from bacterial attachment and biofilm formation on medical implants are posing significant challenges in particular with the emergence of bacterial resistance to antibiotics. Here, we report the design, synthesis and characterization of self-assembled nanostructures, which integrate on their surface antibacterial peptides. The antibacterial WMR peptide, which is a modification of the native sequence of the myxinidin, a marine peptide isolated from the epidermal mucus of hagfish, was used considering its enhanced activity against Gram-negative bacteria...
February 8, 2019: Biomacromolecules
Sara Brännström, Mats Johansson, Eva Malmström
This work demonstrates a versatile and environmentally friendly route for the development of new orthogonal monomers that can be used for post-functionalizable polymer networks. A monomer containing both vinyl ether (VE) and cyclic disulfide moieties was synthesized via enzyme catalysis under benign reaction conditions. The bifunctional monomer could be polymerized to form macromolecues with differing architectures by the use of either cationic or radical photopolymerization. When cationic polymerization was performed, a linear polymer was obtained with pendant disulfide units in the side chain, whereas in the presence of radical initiator, the VE reacted with the disulfide to yield a branched structure...
February 7, 2019: Biomacromolecules
Diana L Philip, Elena A Silantyeva, Matthew L Becker, Rebecca K Willits
Stem cell differentiation towards a specific lineage is controlled by its microenvironment. Polymer scaffolds have long been investigated to provide microenvironment cues; however synthetic polymers lack the specific signaling motifs necessary to direct cellular responses on their own. In this study, we fabricated random and aligned poly(ɛ-caprolactone) nanofiber substrates, surface-functionalized with RGD via strain-promoted azide-alkyne cycloaddition, that were used to investigate the role of a covalently tethered bioactive peptide (RGD) and nanofiber orientation on neural differentiation of mouse embryonic stem cells...
February 6, 2019: Biomacromolecules
Svetlana Bratskaya, Yuliya Privar, Denis Nesterov, Evgeny Modin, Mikhail I Kodess, Arseny Slobodyuk, Dmitry V Marinin, Alexander V Pestov
Here we show that the efficacy of the chitosan interaction with diglycidyl ethers of glycols significantly depends on pH and the nature of acid used to dissolve chitosan. In solutions of hydrochloric acid, cross-linking with diglycidyl ethers of ethylene glycol (EGDGE) and polyethylene glycol (PEGDGE) at room and subzero temperatures yields mechanically stable chitosan gels and cryogels, while in acetic acid solutions only weak chitosan gels can be formed under the same conditions. Combination of elemental analysis, FT-IR spectroscopy, and solid state 13C and 15N NMR spectroscopy was used to elucidate possible differences in the mechanism of chitosan cross-linking in alkaline and acidic media at room and subzero temperatures...
February 6, 2019: Biomacromolecules
Ammu Prhashanna, Phillip A Taylor, Jingya Qin, Kristi L Kiick, Arthi Jayaraman
Elastin-like polypeptides (ELPs) are thermoresponsive biopolymers that undergo an LCST-like phase transition in aqueous solutions. The temperature of this LCST-like transition, Tt  , can be tuned by varying the number of repeat units in the ELP, sequence and composition of the repeat units, the solution conditions, and via conjugation to other biomacromolecules. In this study, we show how and why the choice of guest (X) residue in the VPGXG pentad repeat tunes the Tt of short ELPs, (VPGXG)4 , in the free state and when conjugated to collagen-like peptides (CLPs)...
February 4, 2019: Biomacromolecules
Micha Gorzkiewicz, Marco A Deriu, Maciej Studzian, Anna Janaszewska, Gianvito Grasso, Łukasz Pułaski, Dietmar Appelhans, Andrea Danani, Barbara Klajnert-Maculewicz
Fludarabine is an anticancer antimetabolite essential for modern chemotherapy, but its efficacy is limited due to the complex pharmacokinetics. We demonstrated the potential use of maltose-modified poly(propyleneimine) dendrimer as drug delivery agent to improve the efficiency of therapy with fludarabine. In this study, we elaborated a novel synthesis technique for radioactively-labelled fludarabine triphosphate to prove for the first time the direct ability of nucleotide-glycodendrimer complex to enter and kill leukaemic cells, without the involvement of membrane nucleoside transporters and intracellular kinases...
February 1, 2019: Biomacromolecules
Ya Gao, Mengmeng Hou, Ruihao Yang, Lei Zhang, Zhigang Xu, Yuejun Kang, Peng Xue
Polymeric microneedles have attracted increasing attention as a minimally invasive platform for delivering drugs or vaccines in a more patient-friendly manner. However, traditional microfabrication techniques using negative molds with needle-shaped cavities usually require cumbersome centrifugation and vacuum degassing processes, which have restricted the scaled-up mass production of polymeric microneedles. Herein, a novel polydimethylsiloxane (PDMS)-based negative mold with cavities packed with silk fibroin scaffold is developed for rapid fabrication of polymeric microneedles, which comprise primarily the composition of poly(ethylene glycol) diacrylate (PEGDA) and sucrose as the needle matrix...
January 31, 2019: Biomacromolecules
Zhangchuan Peng, Xi Yang, Chun Liu, Zhaoming Dong, Feng Wang, Xin Wang, Wenbo Hu, Xia Zhang, Ping Zhao, Qingyou Xia
Silkworm silk has excellent mechanical properties, biocompatibility, and promising applications in biomedical sector. Silkworms spin silk at the beginning and end of each of their five instar stages, as well as spinning mature silk after the fifth instar. We evaluated the mechanical properties and structure of 10 kinds of silk fibers from different stages. A tensile test showed that instar beginning silk, instar end silk, and mature silk possess distinct properties. Attenuated total reflectance Fourier-transform infrared spectroscopy and X-ray diffraction results showed that the excellent mechanical properties of instar end silk are attributed to higher β-sheet content and suitable crystallinity...
January 31, 2019: Biomacromolecules
Cuiping Jiang, Zitong Qi, Hengbo Jia, Yilei Huang, Yunbo Wang, Wenli Zhang, Zimei Wu, Hu Yang, Jianping Liu
No abstract text is available yet for this article.
January 30, 2019: Biomacromolecules
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"