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polymer and gene

Ewelina Mnich, Ruben Vanholme, Paula Oyarce, Sarah Liu, Fachuang Lu, Geert Goeminne, Bodil Jørgensen, Mohammed Saddik Motawie, Wout Boerjan, John Ralph, Peter Ulvskov, Birger Lindberg Møller, Nanna Bjarnholt, Jesper Harholt
Lignin is a major polymer in the secondary plant cell wall and composed of hydrophobic interlinked hydroxyphenylpropanoid units. The presence of lignin hampers conversion of plant biomass into biofuels; plants with modified lignin are therefore being investigated for increased digestibility. The bacterium Sphingomonas paucimobilis produces lignin-degrading enzymes including LigD, LigF and LigG involved in cleaving the most abundant lignin inter-unit linkage, the β-aryl ether bond. In this study, we expressed the LigD, LigF and LigG (LigDFG) genes in Arabidopsis thaliana to introduce post-lignification modifications into the lignin structure...
October 24, 2016: Plant Biotechnology Journal
Lili Chen, Fangling Ji, Yongming Bao, Jing Xia, Lianying Guo, Jingyun Wang, Yachen Li
The greatest crux in the combination of chemotherapy and gene therapy is the construction of a feasible and biocompatible carrier for loading the therapeutic drug and gene simultaneously. Here, a new amphiphilic bifunctional pullulan derivative (named as PDP) synthesized by grafting lipophilic desoxycholic acid and low-molecular weight (1kDa) branched polyethylenimine onto the backbone of pullulan was evaluated as a nano-carrier for the co-delivery of drug and gene for potential cancer therapy. PDP exhibited good blood compatibility and low cytotoxicity in the hemolysis and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, respectively...
January 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Yi Lin, Eiichiro Mori, Masato Kato, Siheng Xiang, Leeju Wu, Ilmin Kwon, Steven L McKnight
Two complementary approaches were used in search of the intracellular targets of the toxic PR poly-dipeptide encoded by the repeat sequences expanded in the C9orf72 form of amyotrophic lateral sclerosis. The top categories of PRn-bound proteins include constituents of non-membrane invested cellular organelles and intermediate filaments. PRn targets are enriched for the inclusion of low complexity (LC) sequences. Evidence is presented indicating that LC sequences represent the direct target of PRn binding and that interaction between the PRn poly-dipeptide and LC domains is polymer-dependent...
October 20, 2016: Cell
Jinmin Zhang, Jiankun Yu, Jingzheng Jiang, Xiao Chen, Yanping Sun, Zhen Yang, Tianzhi Yang, Cuifang Cai, Xiaoyun Zhao, Pingtian Ding
Polymers of guanidinylated disulfide containing poly(amido amine)s (Gua-SS-PAAs), have shown high transfection efficiency and low cytotoxicity. Previously we synthesized two Gua-SS-PAA polymers, using guanidino containing monomers (i.e., arginine and agmatine, denoted as ARG and AGM, respectively) and N,N'-cystaminebisacrylamide (CBA). In this study, these two polymers, AGM-CBA and ARG-CBA were complexed with plasmid DNA, and their uptake pathway was investigated. Complexes distribution in MCF-7 cells, and changes on cell endosomes/lysosomes and membrane after the cells were exposed to complexes were tested...
October 20, 2016: Journal of Cellular Biochemistry
Yujing Li, Xueqin Huang, Robert J Lee, Yuhang Qi, Kaikai Wang, Fei Hao, Yu Zhang, Jiahui Lu, Qingfan Meng, Shuai Li, Jing Xie, Lesheng Teng
Polyethylenimine (PEI) as a cationic polymer is commonly used as a carrier for gene delivery. PEI-800 is less toxic than PEI-25K but it is also less efficient. A novel nanocarrier was developed by combining PEI-800 with a pH-sensitive lipid to form polymer-lipid hybrid nanoparticles (P/LNPs). They were synthesized by microfluidic focusing (MF). Two microfluidic devices were used to synthesize P/LNPs loaded with VEGF siRNA. A series of P/LNPs with different particle sizes and distributions were obtained by altering the flow rate and geometry of microfluidic chips, and introducing sonication...
October 17, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Marie Jazzara, Ahmed Ghannam, Chadi Soukkarieh, Hossam Murad
BACKGROUND: Sulfated Polysaccharides (SPs) possess spectrum of pharmacological and therapeutic properties that could attributed to their origins variation, chemical structures and biological activities. Various studies have shown the impact of SPs on proliferation in different cancer cell lines. OBJECTIVES: In this study, we have evaluated the biological effects of λ-carrageenan, a highly SP, extracted from the red seaweed Laurencia papillosa, on MDA-MB-231 cancer cell line...
August 2016: Iranian Journal of Cancer Prevention
Kimberly F Starr, Eric A Porsch, Patrick C Seed, Christian Heiss, Radnaa Naran, L Scott Forsberg, Uri Amit, Pablo Yagupsky, Parastoo Azadi, Joseph W St Geme
Kingella kingae is an encapsulated gram-negative organism that is a common cause of osteoarticular infections in young children. In earlier work, we identified a glycosyltransferase gene called csaA that is necessary for synthesis of the [3)-β-GalpNAc-(1→5)-β-Kdop-(2→] polysaccharide capsule (type a) in K. kingae strain 269-492. In the current study, we analyzed a large collection of invasive and carrier isolates from Israel and found that csaA was present in only 47% of the isolates. Further examination of this collection using primers based on the sequence that flanks csaA revealed three additional gene clusters (designated the csb, csc, and csd loci), all encoding predicted glycosyltransferases...
October 2016: PLoS Pathogens
Junyi Che, Anqi Tao, Shun Chen, Xiaoming Li, Yi Zhao, Weien Yuan
Small interfering RNA (siRNA) has increased the hope for highly-efficient treatment of gene-related diseases. However, the stable and efficient delivery of therapeutic nucleic acids is a prerequisite for the successful clinical translation of RNA interfering therapy. To achieve this, we condensed the low molecular weight polyethyleneimine (PEI, Mw < 2000) with 2,6-pyridinedicarboxaldehyde (PDA) to synthesize a biologically responsive and degradable cationic polymer (abbreviated to PDAPEI) which was utilized as a gene vector for the delivery of a VEGF-A shRNA expression plasmid DNA (pDNA)...
October 19, 2016: Scientific Reports
Mark O'Driscoll
Accurate and efficient replication of the human genome occurs in the context of an array of constitutional barriers including regional topological constraints imposed by chromatin architecture and processes such as transcription, catenation of the helical polymer and spontaneously generated DNA lesions including base modifications and strand breaks. DNA replication is fundamentally important for tissue development and homeostasis; differentiation programmes are intimately linked with stem cell division. Unsurprisingly, impairments of the DNA replication machinery can have catastrophic consequences for genome stability and cell division...
October 18, 2016: Journal of Pathology
Boriphat Methachan, Kamolrat Thanapprapasr
The emergence of theranostics with ultrasound technology is a promising development, as it opens pathways to providing more effective treatments for cancer. Advancements in ultrasound imaging would give a more detailed and accurate image for better diagnosis and treatment planning. Polymeric ultrasound contrast agents (UCAs) are appealing because they are stable and easily modified for active targeting. In addition, a better therapy could be achieved in conjunction with advancements in UCAs. The active targeting not only makes the precise imaging possible, but also leads to targeted delivery of active components to specific local treatment sites...
October 14, 2016: Ultrasound in Medicine & Biology
Anne-Laure Chateigner-Boutin, José J Ordaz-Ortiz, Camille Alvarado, Brigitte Bouchet, Sylvie Durand, Yves Verhertbruggen, Yves Barrière, Luc Saulnier
Cell walls are comprised of networks of entangled polymers that differ considerably between species, tissues and developmental stages. The cell walls of grasses, a family that encompasses major crops, contain specific polysaccharide structures such as xylans substituted with feruloylated arabinose residues. Ferulic acid is involved in the grass cell wall assembly by mediating linkages between xylan chains and between xylans and lignins. Ferulic acid contributes to the physical properties of cell walls, it is a hindrance to cell wall degradability (thus biomass conversion and silage digestibility) and may contribute to pest resistance...
2016: Frontiers in Plant Science
Jacob Barlow, Kevin Gozzi, Chase P Kelley, Benjamin M Geilich, Thomas J Webster, Yunrong Chai, Srinivas Sridhar, Anne L van de Ven
Encapsulating bacteria within constrained microenvironments can promote the manifestation of specialized behaviors. Using double-emulsion droplet-generating microfluidic synthesis, live Bacillus subtilis bacteria were encapsulated in a semi-permeable membrane composed of poly(ethylene glycol)-b-poly(D,L-lactic acid) (mPEG-PDLLA). This polymer membrane was sufficiently permeable to permit exponential bacterial growth, metabolite-induced gene expression, and rapid biofilm growth. The biodegradable microparticles retained structural integrity for several days and could be successfully degraded with time or sustained bacterial activity...
October 15, 2016: Applied Microbiology and Biotechnology
Rosemeyre A Cordeiro, Daniela Santo, Dina Farinha, Arménio Serra, Henrique Faneca, Jorge F J Coelho
: Cationic polymer-based vectors have been considered a promising strategy in gene therapy area due to their inherent ability to condense genetic material and successfully transfect cells. However, they usually exhibit high cytotoxicity. In this work, it is proposed the use of a tailor-made gene carrier based on a tri-block copolymer of poly[2-(dimethylamino)ethyl methacrylate] and poly(β-amino ester) (PDMAEMA-b-PβAE-b-PDMAEMA), the influence of the PβAE length being assessed. For this purpose, three different block copolymers were prepared varying the molecular weight of this segment...
October 12, 2016: Acta Biomaterialia
Mohammad T Abu-Rub, Ben Newland, Michelle Naughton, Wenxin Wang, Siobhan McMahon, Abhay Pandit
Reactive astrocytosis and the subsequent glial scar is ubiquitous to injuries of the central nervous system, especially spinal cord injury (SCI) and primarily serves to protect against further damage, but is also a prominent inhibitor of regeneration. Manipulating the glial scar by targeting chondroitin sulphate proteoglycans (CSPGs) has been the focus of much study as a means to improve axon regeneration and subsequently functional recovery. In this study we investigate the ability of small interfering RNA (siRNA) delivered by a non-viral polymer vector to silence the rate-limiting enzyme involved in CSPG synthesis...
October 12, 2016: Neuroscience
Leise Riber, Mette Burmølle, Martin Alm, Stefan M Milani, Peter Thomsen, Lars H Hansen, Søren J Sørensen
The spread of antimicrobial resistance, usually mediated by horizontal transfer of plasmids, limits the options of treating bacterial infections and thereby poses a crucial human health problem. The disturbance of plasmid stability within bacterial species in clinical environments serves as a novel strategy to reduce the development and dissemination of antibiotic resistance. We tested the ability of irgasan to destabilize plasmids from Escherichia coli K-12 cells when added directly into liquid growth medium at concentrations below levels of marked bacterial growth inhibition, or when released into liquid growth medium from irgasan-impregnated Interpenetrating Polymer Network (IPN) silicone hydrogel objects, a novel technology developed as drug-delivery platform...
October 12, 2016: Plasmid
Yi Zhang, Junkun Duan, Lingguang Cai, Dong Ma, Wei Xue
For cancer gene therapy, a safe and high-efficient gene carrier is a must. To resolve the contradiction between gene transfection efficiency and cytotoxicity, many polymers with complex topological structures have been synthesized, although their synthesis processes and structure control are difficult as well as the high molecular weight also bring high cytotoxicity. We proposed an alternative strategy that using supramolecular inclusion to construct the aggregate from the small molecules for gene delivery, and to further explore the relationship between the topological assembly structure and their ability to deliver gene...
October 14, 2016: ACS Applied Materials & Interfaces
Yuran Xie, Bryan Killinger, Anna Moszczynska, Olivia M Merkel
The use of small interference RNA (siRNA) to target oncogenes is a promising treatment approach for cancer. However, siRNA cancer therapies are hindered by poor delivery of siRNA to cancer cells. Transferrin receptor (TfR) is overexpressed in many types of tumor cells and therefore is a potential target for the selective delivery of siRNA to cancer cells. Here, we used the TfR binding peptide HAIYPRH (HAI peptide) conjugated to cationic polymer branched polyethylenimine (bPEI), optimized the coupling strategy, and the TfR selective delivery of siRNA was evaluated in cells with high (H1299) and low TfR expression (A549 and H460)...
October 10, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Nathan D Schwalm, Guy E Townsend, Eduardo A Groisman
: The utilization of simple sugars is widespread across all domains of life. In contrast, the breakdown of complex carbohydrates is restricted to a subset of organisms. A regulatory paradigm for integration of complex polysaccharide breakdown with simple sugar utilization was established in the mammalian gut symbiont Bacteroides thetaiotaomicron, whereby sensing of monomeric fructose regulates catabolism of both fructose and polymeric fructans. We now report that a different regulatory paradigm governs utilization of monomeric arabinose and the arabinose polymer arabinan...
October 11, 2016: MBio
Jae Ho Shin, Seok Hyun Park, Young Hoon Oh, Jae Woong Choi, Moon Hee Lee, Jae Sung Cho, Ki Jun Jeong, Jeong Chan Joo, James Yu, Si Jae Park, Sang Yup Lee
BACKGROUND: 5-Aminovaleric acid (5AVA) is an important five-carbon platform chemical that can be used for the synthesis of polymers and other chemicals of industrial interest. Enzymatic conversion of L-lysine to 5AVA has been achieved by employing lysine 2-monooxygenase encoded by the davB gene and 5-aminovaleramidase encoded by the davA gene. Additionally, a recombinant Escherichia coli strain expressing the davB and davA genes has been developed for bioconversion of L-lysine to 5AVA...
October 7, 2016: Microbial Cell Factories
Jisoo Shin, Jung Ho Cho, Yoonhee Jin, Kisuk Yang, Jong Seung Lee, Hyun-Ji Park, Hyung-Seop Han, Jinkyu Lee, Hojeong Jeon, Heungsoo Shin, Seung-Woo Cho
Using small interfering RNA (siRNA) to regulate gene expression is an emerging strategy for stem cell manipulation to improve stem cell therapy. However, conventional methods of siRNA delivery into stem cells based on solution-mediated transfection are limited due to low transfection efficiency and insufficient duration of cell-siRNA contact during lengthy culturing protocols. To overcome these limitations, a bio-inspired polymer-mediated reverse transfection system is developed consisting of implantable poly(lactic-co-glycolic acid) (PLGA) scaffolds functionalized with siRNA-lipidoid nanoparticle (sLNP) complexes via polydopamine (pDA) coating...
September 26, 2016: Small
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