China
Africa
Explore chapters and articles related to this topic
Plant-based Nanomaterials and their Antimicrobial Activity
Published in Mahendra Rai, Chistiane M. Feitosa, Eco-Friendly Biobased Products Used in Microbial Diseases, 2022
Mayuri Napagoda, Priyalatha Madhushanthi, Dharani Wanigasekara, Sanjeeva Witharana
Electrospun nanofibers are widely applied as materials for wound dressing. The high oxygen porosity and different pore sizes, high surface to volume ratio as well as the comparable texture of these materials to the natural extracellular matrix in the skin could facilitate the wound healing process. In an early attempt, polycaprolactone (PCL) and polyvinyl pyrrolidone nanofiber mat containing Tecomella undulata extract was fabricated and the antibacterial activity was evaluated against P. aeruginosa, S. aureus and E. coli. The T. undulata extract loaded PCL/PVP nanofiber mat inhibited the growth of the tested bacterial species and demonstrated the possible utility as a wound healing matrix (Suganya et al. 2011). More recently, Fayemi et al. (2018) fabricated polyacrylonitrile nanofibers containing moringa (MR) leaf extracts for wound dressing. These nanomaterials displayed a profound antibacterial activity and wound healing potency signifying their potential to develop into effective wound dressings (Fayemi et al. 2018). Zeyohanness et al. (2018) also prepared electrospun nanofibers containing a plant extract for wound dressing purposes. Ethyl acetate extract of Rhodomyrtus tomentosa and PVA solutions were used for the nanofiber production and the antimicrobial effect of the nanomaterial was determined against E. coli, P. aeruginosa, B. subtilis and E. faecalis. Interestingly, the R. tomentosa loaded PVA nanofiber mats were found to be active against all four bacterial strains tested (Zeyohanness et al. 2018).
Versatile Nature of Poly(Vinylpyrrolidone) in Clinical Medicine
Published in P. Mereena Luke, K. R. Dhanya, Didier Rouxel, Nandakumar Kalarikkal, Sabu Thomas, Advanced Studies in Experimental and Clinical Medicine, 2021
K. R. Dhanya, P. Mereena Luke, Sabu Thomas, Didier Rouxel, Nandakumar Kalarikkal
PVP is considered as an efficient additive for membrane fabrication, nano, micro, and macro filtration process in hemodialysis, wastewater treatment, gas separation and many others. Its excellent compatibility with variety of compounds and strong polar nature makes it a successive polymer for wide range of applications. Poly(acrylonitrile copolymerized with butadienestyrene-PVP membrane is used in water treatment, pharmaceutical, and biotechnology applications. PES coated PVP membrane is usually used in water purification studies. PVP is a versatile polymer used as a template to create well-organized mesoporous silica for enzyme immobilization reactions. The extensive use of PVP as hydrophilizer in membranes and PPO-PVP blends are used in carbon molecular sieving (CMS) membranes.
Other Preventive Methods
Published in J G Webster, Prevention of Pressure Sores, 2019
Sutton et al used pads made of highly structured carbon fibers of about 9 μm in diameter. These were made by carbonizing polyacrylonitrile fibers. Preclinical animal experiments showed that the stress–strain behavior of the pads matched that of the skin within 8 weeks (figure 13.4). In addition, histological examination revealed healthy collagen fibers intertwined with carbon fibers within the implanted pad, and no carbon was found in the paraaortic or lymph nodes. Sutton et al reported the insertion of carbon pads in 23 patients. Figure 13.5 shows postoperative pressure recordings which confirm the effectiveness of such pads in distributing ischial pressures over a larger area.
The Rhei radix rhizoma-based carbon dots ameliorates dextran sodium sulphate-induced ulcerative colitis in mice
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2023
Yifan Zhang, Jie Zhao, Yusheng Zhao, Xue Bai, Yumin Chen, Yuhan Liu, Yue Zhang, Hui Kong, Huihua Qu, Yan Zhao
For UC, inflammation and oxidative stress have been most extensively studied as common cause. RRR-CDs have significant therapeutic effects, both symptomatic treatment and underlying mechanisms of treatment. The mouse tail tip bleeding experiment showed that RRR-CDs can effectively shorten the tail tip bleeding time in mice and achieve the purpose of hemostasis; at the same time, the nanoparticles have a physical adsorption effect [42]. Studies have shown that polyacrylonitrile-based nanofibers obtain hydrophilicity by adding nanoparticles and simulate body fluids to analyse their water absorption capacity [44]. Based on these studies, RRR-CDs can play an effective role in treating acute symptoms such as diarrhoea and blood in the stool to significantly reduce the DAI score and alleviate colon damage.
Acrylonitrile’s genotoxicity profile: mutagenicity in search of an underlying molecular mechanism
Published in Critical Reviews in Toxicology, 2023
Richard J. Albertini, Christopher R. Kirman, Dale E. Strother
ACN is an important high volume industrial chemical. Occupational exposure may occur during its production or use in the manufacture of fibers, resins, polymers, and other chemical intermediates (IARC 1999; EC 2004, USEPA 2011; NTP 2021). Major uses of ACN are in the production of acrylic fibers, which find their way into clothing, carpeting and a multitude of other consumer products, in the manufacture of polyacrylonitrile-based carbon fibers and in the production of polymers of ACN that include butadiene and styrene or styrene alone. Consumers of these products may also be exposed to ACN although levels leached from them are quite small (NTP 2021; Page and Charbonneau 1983, 1985). The greatest potential for high to moderate levels of ACN exposure is occupational. At the environmental level, tobacco is an important source of low-level but chronic exposure to a large segment of the population (IARC 2004 and references therein; Laugesen and Fowles 2005; De Jesús et al. 2020, 2021; NTP 2021). Small amounts of ACN are released during the combustion of plant matter such as biomass and timber. Several studies have quantified emissions of ACN from tropical fires and the burning of biomass (Yokelson et al. 2007; Warneke et al. 2011).
Efficacy and safety of nafamostat mesilate anticoagulation in blood purification treatment of critically ill patients: a systematic review and meta-analysis
Published in Renal Failure, 2022
Yao Lin, Yiming Shao, Yuchun Liu, Ruoxuan Yang, Shuanglin Liao, Shuai Yang, Mingwei Xu, Junbing He
It should be noted that previous studies have demonstrated NM to be adsorbed to the negatively charged dialysis membrane via an ionic bond, including polyacrylonitrile (AN69), acrylonitrile and methallyl sulfonate copolymer (AN69-ST) and J-PAN membranes but not polysulfone (PS), Cuprophan (CU), hemophan (HE), cellulose triacetate (CTA) or polymethylmethacrylate (PMMA) membranes during hemodialysis in vivo [62–66]. These three membrane dialyzers, especially AN69 and AN69-ST, observably adsorb NM and may affect the management of anticoagulant therapy. Since most of the enrolled studies in the present meta-analysis did not provide detailed information regarding hemofilter material, the beneficial effect of NM anticoagulation might have been influenced in patients applied with AN69, AN69-ST or J-PAN membrane dialyzers. Thus, in dialysis circuits using these membrane dialyzers, administration of additional post-hemofilter doses of NM may be useful for the management of anticoagulant therapy. Finally, NM was still not cheap. Although using 16.5 mg/h of NM cost US$160 per day more than heparin (US$5 per day) in Korea in 2013, it may save money through prolongation of filter survival due to the expensive filter [33]. Furthermore, NM might improve the survival outcomes of critically ill patients who received blood purification treatments without increasing the rate of significant bleeding events, which ultimately reduced the medical cost. Thus, NM may be recommended for BPT in patients with high-risk bleeding tendencies, while UFH or other anticoagulants with lower prices can be used for the low-risk groups.