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Marine-Based Carbohydrates as a Valuable Resource for Nutraceuticals and Biotechnological Application
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Rajni Kumari, V. Vivekanand, Nidhi Pareek
The molecular weight of any molecule is defined by the average of all the molecules present in a sample. Molecular weight is one of the significant key characteristics of chitosan that influences various biological and physicochemical properties such as biodegradability, immunogenicity, biocompatibility, mucoadhesion, hydrophilicity, viscosity, solubility, adsorption on solids, elasticity, and water uptake ability. The molecular weight of commercially available chitosan varies from 200 to 1000 KDa according to the use of the initial source material, and it also depends on the type of preparation method used (Ibrahim and EL-Zairy, 2015; Szymańska and Winnicka, 2015).
Drug Design, Synthesis, and Development
Published in Nathan Keighley, Miraculous Medicines and the Chemistry of Drug Design, 2020
Organic synthesis is of paramount importance for creating new drugs. Knowledge of the chemistry of different functional groups enables medicinal chemists to select particular chemical reactions to use to combine molecular fragments and build a predetermined molecular structure of a drug molecule, based on the outcome of computational analysis and lead optimisation processes. Similarly, the required functional groups that are needed for binding to the target can be introduced to the molecular structure by selecting the appropriate chemical reactions for adding a new functional group, or transforming an existing functional group into the one that is required. The chemical reactions needed to produce the novel compound are set out chronologically to yield a recipe for making the new drug, and this is referred to as a synthetic strategy.
Immunology
Published in Rachel U Sidwell, Mike A Thomson, Concise Paediatrics, 2020
Rachel U Sidwell, Mike A Thomson
The MHC genes code for HLA antigens (cell surface glycoproteins) which are present on all tissues and help to identify self from non-self. There are two classes of molecules: Class I HLA-A, B, and C – on all cells except erythrocytes and trophoblast cellsClass II HLA-DP, DQ and DR – on T and B cells, monocytes and dendritic cells; inducible on endothelial and epithelial cells
In silico QSAR modeling to predict the safe use of antibiotics during pregnancy
Published in Drug and Chemical Toxicology, 2023
Feyza Kelleci Çelik, Gül Karaduman
Molecular descriptors are defined as mathematical representations of the properties of molecules created by algorithms. Molecular descriptors’ numerical values are utilized to quantitatively describe the chemical and physical information of the molecules (Chandrasekaran et al.2018). The appropriate descriptors chosen for each model may differ depending on the structure of the molecules and the expected toxicological effect. For example, it has been shown that among the prominent descriptors adopted in toxicity prediction applications, ‘molecular property’, ‘connectivity’, and ‘topological’ are the three most essential descriptors for toxicity prediction applications (Li 2020). Our study also included the descriptors in the Chi Connectivity Indices, Electrotopological State Indices (E-State), Constitutional Descriptors, and Molecular Fragments sections that contributed to creating the most successful model.
Application of plant-derived exosome-like nanoparticles in drug delivery
Published in Pharmaceutical Development and Technology, 2023
Mohadeseh Barzin, Amir Mohammad Bagheri, Mandana Ohadi, Amir Masoud Abhaji, Soodeh Salarpour, Gholamreza Dehghannoudeh
Proteins are macro-biomolecules composed of amino acid residues and perform a wide variety of functions, including DNA replication, stimuli responding, transferring molecules, and catalyzing metabolic reactions (Whitford 2013; Fuxreiter and Vendruscolo 2021). Suharta et al. (2021) revealed that PELNs have a low concentration of protein; Further, most proteins in PELNs are cytosolic proteins, including proteases, actin, and membrane proteins that act as transporters within the membrane. However, determining a complete protein profile inside PELNs is challenging due to various sets of protein databases in different plants (Suharta et al. 2021; Woith et al. 2021). For instance, Ju et al. (2013) identified 580 proteins of lemon-derived exosomes. On the other hand, compared to exosomes extracted from animal cells, PELNs have lower protein content. Somehow, mammalian-derived exosomes contain more than 1000 proteins, whereas plant exosomes derived from ginger have only 28 proteins (Raimondo et al. 2015; Zhang et al. 2016; Salek et al. 2020; Suharta et al. 2021). Moreover, it should be noted that proteins are assumed to play a critical role in interspecies recognition within the plant and mammalian cells (Song et al. 2020; Nemati et al. 2022). For example, lectin proteins, which have a high specific affinity for saccharides and are abundantly found in some plant-derived exosomes such as garlic and mushrooms, are supposed to be the primary interspecies communication mediators between these exosomes and mammalian cells (Song et al. 2020).
Crosslinking hyaluronic acid soft-tissue fillers: current status and perspectives from an industrial point of view
Published in Expert Review of Medical Devices, 2021
Jimmy Faivre, Amos I. Pigweh, Julien Iehl, Pauline Maffert, Peter Goekjian, François Bourdon
Between its functional groups, the crosslinker bears a spacing backbone that has a prevailing role during the gel manufacturing. Indeed, the solubility of the crosslinker in aqueous media, mainly due to the spacer physico-chemical properties, must be sufficient to avoid precipitation during manufacturing and promote efficient chemical bonding with HA. To meet this criterion, molecules with polar functionality are preferred. For instance, BDDE and DVS both have a LogP of 0.4 conferring sufficient miscibility in water despite the presence of central butanediol or divinyl chains, respectively (Table 1). PEGDE is a hydrophilic polymer which has a size distribution (dispersity) centered around a mean value of several hundreds of daltons, in other words, it is a mixture of oligomers, which differentiate PEGDE from all the other commercially used crosslinkers. PEGDE has a negative LogP value that indicates high-water solubility and also an increased capacity to adsorb water. On the other hand, the less soluble crosslinker is BCDI has a LogP of 2.4. The poor water solubility of this crosslinker due to the presence of a phenyl ring generally leads to the use of organic co-solvents during the crosslinking step that requires extensive purification and characterization of the resulting gel.