Optical Nanoprobes for Diagnosis
D. Sakthi Kumar, Aswathy Ravindran Girija in Bionanotechnology in Cancer, 2023
Polyesters exemplify the most extensively employed class of polymers, owing to their biodegradable and biocompatible qualities. These include polylactide (PLA), polyglycolide (PGA), poly(e-caprolactone) (PCL), and poly(g-valerolactone) (PVL), and most of them are generally synthesized by ring-opening polymerization of lactide, lactide/glycolide, e-caprolactone, and gvalero-lactone, respectively. PLGA copolymer of lactide and glycolide is the Food and Drug Administration (FDA) approved polymer for drug delivery applications. Amphiphilic PLGA-b-PEG or PLA-b-PEG copolymers, comprising hydrophobic PLGA or PLA block and a hydrophilic PEG, have been used to prepare NPs, polymersomes, or micelles, where the hydrophobic part (PLGA or PLA) and hydrophilic PEG results in the formation of core and shell of nanocarriers, respectively. PEGylated NPs demonstrate the potential to be functionalized with various ligands, such as small molecules, peptides, antibodies, and aptamers conjugated to PEG chain. There have been several reports on the application of PNPs as diagnostic as well as therapeutic (theragnostic) multifunctional agents. PLGA NPs carrying various drugs (curcumin, paclitaxel, gemcitabine, 5-Fluorouracil (5FU), etc.) with different targeting moieties (folate, aptamer, peptide, transferrin, etc.) against pancreatic as well as breast cancer cells have been reported [175–178].
Polymeric Colloidal Carriers for Natural Polyphenolic Compounds
Madhu Gupta, Durgesh Nandini Chauhan, Vikas Sharma, Nagendra Singh Chauhan in Novel Drug Delivery Systems for Phytoconstituents, 2020
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).
Synthetic Polymers in Cosmetics
E. Desmond Goddard, James V. Gruber in Principles of Polymer Science and Technology in Cosmetics and Personal Care, 1999
When considering the many cosmetically useful synthetic polymers, it is interesting to find that very few condensation polymers, that is, polyesters and polyamides, have found widespread cosmetic utility (we will see a few examples of condensation polymers in the sections on hair fixative and encapsulating polymers). The reason for this lies in the nature of the chemical bonds that hold these condensation polymers together. These polymers, in most cases, are the result of a condensation reaction that itself expels a molecule of water or a low-molecular-weight alcohol. Consequently, these polymers tend to be unstable in the aqueous environments of most cosmetic formulations. Also, if a cosmetic is applied to the hair or skin, it must be removed later. The polyesters and polyamides typically have low water solubility and are, consequently, not readily removed in the washing process.
Nose-to-brain delivery of borneol modified tanshinone IIA nanoparticles in prevention of cerebral ischemia/reperfusion injury
Published in Drug Delivery, 2021
Luting Wang, Lin Xu, Junfeng Du, Xiao Zhao, Mei Liu, Jianfang Feng, Kaili Hu
TSA is the major active ingredient of a Traditional Chinese Medicine (TCM) Salvia miltiorrhiza, which has been widely used for the treatment of cerebrovascular diseases (Han et al., 2008). Modern clinical and pharmacological studies have shown a variety of activities of TSA such as significant inhibition of the degree of peroxidation, decrease the toxicity of excitatory amino acid, inhibit Ca2+ overload, decrease NO release, inhibit mitochondrial damage, decrease oxygen free radicals level, regulate the immunoinflammatory process, and inhibit apoptosis (Dong et al., 2018). Besides the notable curative effects for cardiovascular and cerebrovascular diseases, TSA also indicates various activities that might be effective in protection for CIRI (Tang et al., 2010; Liu et al., 2010a, 2011). However, due to the poor solubility of TSA, rapid plasma clearance, and P-gp efflux, it is difficult to pass through the blood–brain barrier (BBB), which greatly limits its therapeutic effect on CIRI. In this study, polymeric NPs were chosen to improve the brain targeting of TSA after IN administration. The variability of polymer carrier can give drug delivery system many new characteristics. Polyester materials are widely used because of their biodegradability, good biocompatibility, and safety. Free design of polymer chain length can produce different particle size, drug delivery capacity, and biological effects.
Artificial hair implantation for hair restoration
Published in Journal of Dermatological Treatment, 2022
Aditya K. Gupta, Maanasa Venkataraman, Emma M. Quinlan
In the early days, artificial fibers consisted of synthetic fibers made of monoacrylic,polyacrylic, or polyester materials, or natural fibers, such as processed human hair (21). Manufacturers of present-day synthetic fibers (Biofibre®, Nido Z-type) state that the problems associated with earlier fibers such as non-biocompatibility, tolerability, and safety have been resolved; currently available synthetic fibers are made of polyamide material which are claimed to be inert, safe, and tolerable (21). Biofibre® medical hairs are available in 13 colors, different lengths (15, 30, or 45 cm), and various shapes (straight, wavy, and curly) (13,21). MHD® (released in 2014) is a high-density version of regular Biofibre® hairs which are implanted only in the crown area, while the lightweight regular Biofibre® hairs are used to populate the front hairline, which has thin dermal tissue (23). Besides androgenetic alopecia, the use of synthetic hair fibers has been reported in the treatment of other alopecias, for example, pharmacological, primary cicatricial (scarring alopecia due to innate hair follicle-directed causes), and secondary cicatricial (scarring alopecia due to incidental causes such as traumatic burns and surgical scars) (23,26). However, the role of artificial hair implantation in treating other types of alopecias, such as triangular temporal alopecia, has not been reported.
Wet-wrap therapy with halometasone cream for severe adult atopic dermatitis
Published in Postgraduate Medicine, 2018
Wei Xu, Yan Li, Zeyu Chen, Teng Liu, Shan Wang, Linfeng Li
In the current study, we treated the 12 patients with WWT and found significant reductions in the scores of SCORAD, pruritus, IGA, and DLQI after the WWT. These results suggest that the WWT appears to effectively relieve symptoms such as pruritus, reduce skin lesions, and improve quality of life in patients with severe AD. Our previous studies have demonstrated that halometasone cream can treat chronic generalized eczema quickly and effectively [20]. Halometasone cream at a dosage of 15 g daily for 14 days may not effect patients’ endogenous cortisol levels, but halometasone cream at >20 g daily can significantly reduce serum cortisol levels [20]. In the current study, we used 15 g halometasone cream daily on the lesions on the torso and limps in the WWT and used 0.1% tacrolimus ointment on head and neck. The TCS was used together with Vaseline ointment. The treatment frequency and duration was twice daily for two hours every time for 7 days. The quality of the AllerMate wet-wrap bandage used in the current study was comparable to that of Tubifast®. The material is lightweight and breathable, made from spandex, viscose, and polyester, and is very comfortable and safe to wear.
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