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Detection and Description of Tissue Disease: Advances in the Use of Nanomedicine for Medical Imaging
Published in Dan Peer, Handbook of Harnessing Biomaterials in Nanomedicine, 2021
Jason L. J. Dearling, Alan B. Packard
Gold nanoparticles (AuNPs) also have potential application in this field, with gold’s higher atomic number (79) than iodine (53) resulting in greater attenuation of x-rays. As with bismuth particles, AuNPs have to be coated, for example with gum Arabic, to reduce their hematological and renal toxicity [19]. They have been shown to be stable in vivo and to produce good contrast in CT applications [19, 20]. Another advantage of AuNPs is that they have a large surface-area-to-volume ratio, providing more opportunity for surface modification. For example, Aydogan et al. reported the modification of AuNPs with a structural analogue of glucose, 2-deoxy-D-glucose (2DG) [21]. This modification increased their uptake by tumor cells in vitro by a factor of 4 compared with unmodified AuNPs, although the exact mechanism of uptake has yet to be fully defined. In another example, targeting was achieved by entrapping AuNPs in dendrimers, then targeting the combined nanoparticle using folate attached to the outside of the dendrimer, resulting in improved binding to KB cells (human epithelial carcinoma cells) in vitro [22].
Amphiphilic Systems as Biomaterials Based on Chitin, Chitosan, and Their Derivatives
Published in Severian Dumitriu, Valentin Popa, Polymeric Biomaterials, 2020
Chitosan is a linear polysaccharide obtained by extensive deacetylation of chitin. It is mainly composed of two kinds of β (1 → 4) linked structural units: 2-amino-2-deoxy-d-glucose and N-acetyl-2-amino-2-deoxy-d-glucose. However, since it is virtually impossible to completely deacetylate chitin, what is usually known as chitosan is a family of chitins with different degrees of acetylation (defined as the molar fraction of acetylated units) lower than 50%. The capacity of chitosan to dissolve in dilute aqueous solutions is the commonly accepted criterion to differentiate it from chitin. Chitosan is also present in significant quantities in some fungi, such as Mucor rouxii (30%) and Choanephora cucurbitarum (28%), although again associated with other polysaccharides.
Advances in imaging simulation for lung cancer IGRT
Published in Jing Cai, Joe Y. Chang, Fang-Fang Yin, Principles and Practice of Image-Guided Radiation Therapy of Lung Cancer, 2017
Jing Cai, Daniel Low, Tinsu Pan, Yilin Liu, Zheng Chang, Wei Lu
Radiation therapy of lung cancer is among the most common and important areas of image-guided radiation therapy. Imaging simulations including computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography with 2-fluorine-18 fluoro-2-deoxy-D-glucose (FDG-PET) and FDG-PET combined with CT (FDG-PET/CT) are currently being used for clinical assessment of lung cancer. Recent technological advances in these imaging systems hold great promises to produce marked improvements toward more precise treatment of lung cancer. In this chapter, we will focus on recent advances in CT, MRI, PET, and other imaging methods in lung cancer applications, and discuss their potentials and limitations for use in clinical practice.
Novel chitosan/citric acid modified pistachio shell/halloysite nanotubes cross-linked by glutaraldehyde biocomposite beads applied to methylene blue removal
Published in International Journal of Phytoremediation, 2023
Chitosan is a highly preferred biopolymer today because it is produced from economically very cheap and renewable resources. Chitosan, a deacetylated derivative of chitin, is a cationic polysaccharide that contains β-(1,4)-2-acetoamido-2-deoxy-D-glucose and β-(1,4)-2-amino-2-deoxy-D-glucose. due to the presence of amino (–NH2) groups in the chitosan structure, it dissolves in acidic environments (pH < 6), in some acid solutions such as formic acid, acetic acid, lactic acid, and becomes a polycationic polymer. Acetic acid is generally used as the standard solvent (Figure 1). The solubility of chitosan in acidic media limits its use for adsorbing dyes. Since chitosan is a cationic structure, its use in the adsorption of some substances is advantageous, but the adsorption amount and adsorption rate need to be improved (Liu et al. 2013). Therefore, supporting modifications or compositing methods were used in studies (Peng et al. 2015).
Glucosamine modulates membrane and cellular ionic homeostasis: studies on accelerated senescent and naturally aged rats
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Komal Saraswat, Raushan Kumar, Syed Ibrahim Rizvi
Glucosamine (GlcN), 2-amino-2-deoxy-D-glucose, is a naturally occurring amino sugar found in the human body. It is an important component of glycoproteins, proteoglycans, and glycosaminoglycans, which is a major component of joint cartilage [10]. GlcN has a potent background as a glycolytic inhibitor [11,12]. Its entry into cells is stimulated by insulin and involves the glucose-transporter system [13]. GlcN in its phosphorylated form (GlcN-6-phosphate), acts as an inhibitor of hexokinase, the first enzyme of glycolysis. Researchers have introduced a novel biological and pharmacological application of GlcN as a caloric restriction mimetic (CRM) [14]. Recently, we have reported that GlcN supplementation results in an improvement in aging biomarkers in erythrocytes and plasma by inducing a transient mitohormetic increase in ROS [15].
Subtraction technique on 18F-fluoro-2-deoxy-d-glucose positron emission tomography (18F-FDG-PET) images
Published in The Imaging Science Journal, 2022
Xuewei Mao, Wei Shan, Wilson Fox, Jinpeng Yu
Autoimmune encephalitis (AE) associated with leucine-rich glioma-inactivated 1 (LGI1) antibody is a rare but severe neurological disease [1]. 18F-fluoro-2-deoxy-d-glucose positron emission tomography (18F-FDG-PET) plays a crucial role in the diagnosis of anti-LGI1 encephalitis [2–4]. According to previous reports, 18F-FDG-PET mainly presents with hypermetabolism in the medial temporal lobe (MTL) and basal ganglia (BG) [5]. However, the results of PET can be influenced by many factors [6,7], such as patient status, radioactive medicine, and scanning time, which may easily induce lower accuracy and different metabolism of background tissues. Therefore, previous hypermetabolism studies on subjects with anti-LGI1 encephalitis may be inaccurate due to the interference of the altered cortical metabolism of different individuals. For example, the cortex may exhibit different degrees of hypermetabolism, while PET showed similar degrees in the BG. In that case, the accuracy of the BG is unclear, and only limited pure visual analysis is conducted.