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From Conventional Approaches to Sol-gel Chemistry and Strategies for the Design of 3D Additive Manufactured Scaffolds for Craniofacial Tissue Engineering
Published in Vincenzo Guarino, Marco Antonio Alvarez-Pérez, Current Advances in Oral and Craniofacial Tissue Engineering, 2020
A. Gloria, T. Russo, M. Martorelli, De Santis R.
Regarding synthetic polymers, polylactic acid (PLA), polyglycolide (PGA), poly(lactide-co-glycolide) (PLGA), poly(E-caprolactone) (PCL), polyhydroxyalkanoates (PHAs) and (propylene fumarate) (PPF). Such polymers have been developed to tailor the mechanical properties of the scaffolds by varying the degrees of cross-linking and concentration or by means of copolymerization strategies (Thrivikraman et al. 2017).
Packaging and Shelf-Life Evaluation of Shoots
Published in Nirmala Chongtham, Madho Singh Bisht, Bamboo Shoot, 2020
Nirmala Chongtham, Madho Singh Bisht
Some of the packaging materials mainly plastic-based are non-degradable, non-reusable and non-recyclable which augment environmental waste and there is also an issue of mobilization of low molecular weight constituents like stabilizers, plasticizers, monomers and oligomers from the packaging material to the food product. The use of biopolymers for packaging can overcome these drawbacks, like polyesters, which could either directly be extracted from proteins, lipids and polysaccharides or can be synthesized by polymerization e.g. aliphatic-aromatic copolymers, aliphatic polyesters, polylactic aliphatic copolymers. Bio-based polymers that are renewable like poly lactic acid, oil-based monomers such as polycaprolactone, micro-organisms generated material like polyhydroxyalkanoates can be used to prepare packaging material and thereafter their application on bamboo shoots can be studied. Application of nanocomposites has also been introduced for food packaging but there is limited scientific data on their toxicological effect on humans or migration of nanoparticles to food, which must further be explored.
Polymeric Colloidal Carriers for Natural Polyphenolic Compounds
Published in Madhu Gupta, Durgesh Nandini Chauhan, Vikas Sharma, Nagendra Singh Chauhan, Novel Drug Delivery Systems for Phytoconstituents, 2020
Maria Rosaria Lauro, Teresa Musumeci, Francesca Sansone, Giovanni Puglisi, Rosario Pignatello
In recent years, different authors have developed colloidal carriers to protect and control the release of polyphenols using aliphatic polyesters, which can be of microbial origin or obtained by chemical synthesis. They include poly-lactide (PLA), poly (lactide-co-glycolide) (PLGA), poly-ε-caprolactone (PCL), polyhydroxyalkanoates (PHAs), and their copolymers and derivatives. Due to their controlled delivery properties, biodegradability, and biocompatibility, their application is of great interest to the biomedical field. These polymers show ideal features for encapsulating lipophilic compounds. Biodegradable polyesters can be classified with regard to the mode of bonding of the constituent monomers: (i) poly (hydroxy acid)s with –O–R–CO– as repeating monomeric units, such as poly (3-hydroxybutyrate) [P (3HB)], PLA, poly (glycolic acid) (PGA), PCL, etc.; and (ii) poly (alkylenedicarboxylate)s, i.e., poly (ethylene succinate) (PESu), poly (butylene succinate) (PBSu), poly (ethylene adipate) (PEA), and poly (butylene adipate) (PBA). Biodegradable polyesters can be further split into two groups: (i) biomass-based polyesters (microbial origin), such as PLA, P (3HB), and their copolymers, and (ii) petroleum-based aliphatic polyesters such as PGA, PCL, PBA, poly (3-hydro propionate) (PHP), and PBSu. Synthetic polymers offer the advantage of higher purity and reproducibility with respect to natural polymers. Conversely, polyesters from microbial origin can be produced from renewable raw materials, thus playing a potential role in environmentally-friendly industry and green chemistry strategies (Chanprateep, 2010).
A comprehensive proteomics analysis of the response of Pseudomonas aeruginosa to nanoceria cytotoxicity
Published in Nanotoxicology, 2023
Lidija Izrael Živković, Nico Hüttmann, Vanessa Susevski, Ana Medić, Vladimir Beškoski, Maxim V. Berezovski, Zoran Minić, Ljiljana Živković, Ivanka Karadžić
The downregulation of glutathione (GSH)-related enzymes (glutathione peroxidase and hydrolase), (Table 1) and unaltered levels of glutathione reductase (Supplementary Table 1) is intriguing, since disturbed redox homeostasis usually increases the amount of glutathione and related enzymes in the cell. The reduction potentials of pyocyanin and GSH point out their direct reaction, as well as the reaction between GSH and ROS induced by pyocyanin, both depleting intracellular GSH levels. This is only partially reimbursed by glutathione reductase, leaving cells deficient in GSH and more sensitive to redox stress (Das et al. 2017). Interestingly, the downregulation of polyhydroxyalkanoate synthesis protein, PhaF, was found. This enzyme can cause lowered synthesis of polyhydroxyalkanoates, which function as a reducing equivalent pool to maintain cellular redox balance (Ayub, Tribelli, and Lopez 2009). The lack of polyhydroxylalkanoate implies altered redox homeostasis and fatty acid biosynthesis, as found in this study. Upregulation of flavoprotein pyridine nucleotide transhydrogenase, responsible for the conversion of NADPH to NADH, and ferredoxin-NADP reductase (Table 1), was observed, aligning with enhanced superoxide radical production.
Nanomaterials in tuberculosis DNA vaccine delivery: historical perspective and current landscape
Published in Drug Delivery, 2022
Xing Luo, Xiaoqiang Zeng, Li Gong, Yan Ye, Cun Sun, Ting Chen, Zelong Zhang, Yikun Tao, Hao Zeng, Quanming Zou, Yun Yang, Jieping Li, Hongwu Sun
Polyhydroxy biopolyester nanoparticles include poly (3-hydroxybutyrate) (PHB) and polyhydroxyalkanoates (PHA); PHB is commonly extracted and purified from E. coli and Lactococcus lactis. Antigens carried on specific nanoparticles are preferentially recognized and presented, enhancing the ability of cells to respond to immunogens (Khader et al., 2007). TB DNA vaccines containing PHB nanoparticles with ESAT-6 or Ag85A (the dominant antigens of M. tuberculosis) on the surface of biological beads induce high levels of cytokines interleukin (IL)-2, IFN-γ, tumor necrosis factor (TNF)-α, IL-17A, and IL-6 on intramuscular injection. According to Parlane et al., these bovine-TB vaccines cause a high T-cell immune response, with both CD4+ and CD8+ involved in the induction of IFN-γ release (Parlane et al., 2014). In TB DNA vaccines, PHA nanoparticles have been produced using bacteria (via bioengineering) as intracellular contents when carbon sources are abundant (Grage et al., 2009).
Understanding the basis of medical use of poly-lactide-based resorbable polymers and composites – a review of the clinical and metabolic impact
Published in Drug Metabolism Reviews, 2019
Sergiu Vacaras, Mihaela Baciut, Ondine Lucaciu, Cristian Dinu, Grigore Baciut, Liana Crisan, Mihaela Hedesiu, Bogdan Crisan, Florin Onisor, Gabriel Armencea, Ileana Mitre, Ioan Barbur, Winfried Kretschmer, Simion Bran
Other biodegradable polyesters in use are:PHA – polyhydroxyalkanoatesPHH – polyydroxyhexanoatesPHB – polyhydroxybutyratePHV – polyhydroxyvaleratePCL – polycaprolactonePBS – polybutylene succinatePBSA – polybutylene succinate adipateAAC – aliphatic–aromatic copolyestersPET – polyethylene terephthalatePBAT – polybutylene adipate/terephthalatePTMAT – polymethylene adipate/terephthalate (Nampoothiri et al. 2010)