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Antiviral Nanomaterials as Potential Targets for Malaria Prevention and Treatment
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Kantrol Kumar Sahu, Sunita Minz, Madhulika Pradhan, Monika Kaurav, Krishna Yadav
Pinocytosis is classified as caveolae-mediated endocytosis, clathrin-mediated endocytosis clathrin- and caveolae-independent endocytosis, and micropinocytosis (Sun et al. 2019) (Table 18.2). Caveolar-mediated endocytosis is a clathrin-independent endocytotic mechanism involving bulb-shaped caveolae. Caveolae are 50-60 nm plasma membrane invaginations. Caveolae are formed by caveolins, which are integral membrane proteins, and cavins are peripheral membrane proteins. Clathrin-mediated endocytosis possesses complex protein machinery that transiently assembles on the plasma membrane and creates clathrin-coated endocytic vesicles. This machinery selects and concentrates cargo molecules and shapes the membrane into a vesicle.
Emerging Antiviral Technology
Published in Peerawatt Nunthavarawong, Sanjay Mavinkere Rangappa, Suchart Siengchin, Mathew Thoppil-Mathew, Antimicrobial and Antiviral Materials, 2022
Vinaya Tari, Karthik Kannan, Vinita Vishwakarma
Hydrophilic therapeutic agents capable of being introduced inside the aqueous core. The liposome is the first commercialized nanostructure introduced in 1965, and it is mainly used as a drug delivery system. Liposome consists of at least one lipid bilayer (natural of synthetic phospholipids), and inside is an aqueous core [9]. There are many types of liposomes, viz. multilamellar vesicles, unilamellar vesicles, large unilamellar vesicles, etc. Usually, liposomes vary from 40 nm to 10 pm as per their synthesis. However, lipophilic agents are formed in the lipid bilayer, and their efficiency depends on hydrophobicity and membrane fluidity. The spleen phagocytic cells recognize liposomes rapidly after introduction in the body. However, the engulfment of liposomes by the phagocytic cells can be reduced with the help of polyethylene glycol (PEG) through chemical modification of liposomes [5-6]. There are some disadvantages of liposome nanostructure, viz. poor stability in vivo and in vitro, high production cost, and low efficacy of therapeutics in the lipid bilayer and aqueous core [5, 9], The cellular translocation enhancement through the transactivator of transcription of HIV, i.e., TAT peptide, was achieved by introducing it into the liposome [10, 32].
Lysosomal Storage Disorders and Enzyme Replacement Therapy
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2020
Lysosomes are spherical membrane-bound vesicles containing more than 60 different enzymes within the organelle’s membrane and its lumen. These enzymes, synthesized in the rough endoplasmic reticulum and tagged with a mannose 6-phosphate residue, are capable of degrading material no longer required by an organism, and the pH value between 4.5-5.0 in the lumen is optimal for degradation of waste molecules by hydrolysis.
Expression levels of selected cytokines and microRNAs in response to vitamin D supplementation in ultra-marathon runners
Published in European Journal of Sport Science, 2020
D. Pastuszak-Lewandoska, D. Domańska-Senderowska, J. Kiszałkiewicz, P. Szmigielska, A. Snochowska, W. Ratkowski, M. Spieszny, T. Klocek, P. Godlewski, P. Cięszczyk, E. Brzeziańska-Lasota, A. V. September, M. J. Laguette
The design of this study, linking the expression levels of mRNAs of several pro-inflammatory factors to inflammatory miRNAs together with the influence of vitamin D supplementation, does not replicate any early work performed in ultra-marathon runners. However, further larger studies are required towards the recognition of the studied cytokines and miRNAs as direct markers of overtraining and adaptation to extreme exercise dose. The origin of the circulating exosomal inflamma-miRs also warrants further investigation. These structures are extracellular vesicles generated by all cell types and play key roles in intercellular communication. It is plausible that they originate from the muscles after the extreme endurance exercise (UM) or immune cells as a result of the strenuous physical activity.
Extracellular vesicles released in response to respiratory exposures: implications for chronic disease
Published in Journal of Toxicology and Environmental Health, Part B, 2018
Birke J. Benedikter, Emiel F. M. Wouters, Paul H. M. Savelkoul, Gernot G. U. Rohde, Frank R. M. Stassen
EV are small membrane-enclosed vesicles that are postulated to be released by all cell types and are detected in a variety of human body fluids, including nasal lavage fluid (Lasser et al. 2011), bronchoalveolar lavage fluid (BALF) (Admyre et al. 2003), and blood (Wolf 1967). These vesicles carry a complex cargo of proteins, RNA, and lipids that makes them potent entities of intercellular communication (Van Niel, D’Angelo, and Raposo 2018). EV-borne proteins bind to cell surface receptors and trigger intracellular signal transduction (Camussi et al. 2011). In addition, EV fuse with the membrane of their target cells and thereby deliver functional RNA and proteins that modulate target cellular activity (Camussi et al. 2011). Finally, certain EV-bound proteins exert functions in the extracellular space, such as remodeling of the extracellular matrix (Lacroix and Dignat-George 2013).
Photoinduced flavin-tryptophan electron transfer across vesicle membranes generates magnetic field sensitive radical pairs
Published in Molecular Physics, 2019
Lewis M. Antill, Shin-ya Takizawa, Shigeru Murata, Jonathan R. Woodward
The magnetic field sensitivity of photochemical reactions is of relevance across diverse disciplines from solid-state photonic devices to animal navigation. In the case of the latter, many different animal species are known to be able to use the geomagnetic field for orientation and navigation, an ability referred to as magnetoreception. The mechanism by which this process operates is still under debate. One hypothesis, chemical magnetoreception, involves the radical pair mechanism (RPM), in which magnetic fields can influence the rate and yield of chemical reactions [1]. The proposed receptor molecule in this hypothesis is the blue-light receptor protein, cryptochrome [2]. Cryptochrome photochemistry involves photoinduced intermolecular electron transfer reactions, which produce radical pairs (RPs) comprised of a reduced flavin cofactor and an oxidised tryptophan (Trp) residue inside the protein [3]. Immobilisation of flavins is desirable to simulate the orientationally structured protein environment of cryptochrome. Vesicles (liposomes) are mimetic systems for cell membranes, which are self-assemblies formed by phospholipid or synthetic surfactants that form bilayers. They can be defined by three distinct regions: the inner water pool, the hydrophobic bilayer, and the homogeneous aqueous solution. Vesicles are more ordered and have longer lifetimes than other aggregates such as micelles [4,5]. In this work, we study the photochemistry and magnetosensitivity of flavins (electron acceptors) and tryptophan (electron donor) in DPPC small unilamellar vesicles (SUV, diameter ∼60 nm), reporting transmembrane electron transfer (ET) reactions across both single and double membrane layers.