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3D-Printed Nanocrystals for Oral Administration of the Drugs
Published in Yasser Shahzad, Syed A.A. Rizvi, Abid Mehmood Yousaf, Talib Hussain, Drug Delivery Using Nanomaterials, 2022
Lucía Lopez-Vidal, Daniel Andrés Real, Alejandro J. Paredes, Juan Pablo Real, Santiago Daniel Palma
Enhanced adhesion to cell-surface membranes: Drug delivery systems must cross several barriers to reach their site of action. One such barrier is the dynamic semi-permeable barrier of mucus. Mucus is a complex aqueous mixture of glycoproteins, lipids, and salts that coats the epithelial barriers of various organs (gastrointestinal, ocular, respiratory, etc.). These polymers form a negatively charged hydrophilic network that prevents or limits the absorption of mainly hydrophobic substances.
Basic Chemical Hazards to Human Health and Safety — I
Published in Jack Daugherty, Assessment of Chemical Exposures, 2020
Sputum production increases with irritation, and the nasal passages become inflamed, as well as the trachea and upper bronchial passages. Development of bronchitis means that the cilial clearance mechanism is compromised. The accumulation of mucus increases the risk of secondary bacterial infection. Wheezing may develop where the exposed person has a history of hyperactive airway disease.
Mucoadhesive Chitosan-Based Nanoparticles for Oral Drug Delivery
Published in Emmanuel Opara, Controlled Drug Delivery Systems, 2020
Xin Zhang, Jian Guan, Shirui Mao
The surface of the gastrointestinal tract is covered with a mucus layer. The multifunction of mucus including lubricating and selective permeation, which allows the body’s required nutrients to enter the human body and blocks the harmful substances such as most bacteria and pathogens, is vital to the human body.
Influence of o,p′-DDT on MUC5AC expression via regulation of NF-κB/AP-1 activation in human lung epithelial cells
Published in Journal of Toxicology and Environmental Health, Part A, 2021
Gi Ho Lee, Sun Woo Jin, Jae Ho Choi, Eun Hee Han, Yong Pil Hwang, Chul Yung Choi, Hye Gwang Jeong
Airway mucus is a complex hydrophilic gel composed of mucins, proteins, salts, lipids, and water. Mucins are high-molecular-weight glycoproteins composed of repeating structures with varying numbers of specific amino acids including serine, threonine, and proline (Kim 2012). At least 16 mucin genes are expressed in the human lung (MUC1, 2, 4, 5AC, 5B, 7, 8, 11, 13, 15, 16, 18, 19, 20, 21, and 22) (Davies et al. 2007; Rose and Voynow 2006). Mucin 5AC (MUC5AC) is a major gel-forming mucin present in secretions from goblet cells, and its expression is inducible during airway inflammation (Choi et al. 2011). Inflammatory mediators including phorbol myristate acetate (PMA) and tumor necrosis factor-α (TNF-α) induce airway MUC5AC formation through the activity of transcription factors, including nuclear factor kappa-b (NF-κB), activator protein 1 (AP-1), and specificity protein-1(SP-1) (Choi et al. 2011; Hewson, Edbrooke, and Johnston 2004; Lim et al. 2009). Further, oxidants generated from irritant chemicals, such as cigarette smoke and fine particulate matter, produce lung inflammation via reactive oxygen species, Akt, and the mitogen-activated protein kinase (MAPK) signaling pathway in lung epithelial cells (Arooj et al. 2020; Kovacic and Somanathan 2009; Lee et al. 2019; Liu et al. 2018; Mossman, Lounsbury, and Reddy 2006).
Analysis of the volume of fluid (VOF) method for the simulation of the mucus clearance process with CFD
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
Concepción Paz, Eduardo Suárez, Jesús Vence, Adrián Cabarcos
A thin mucus layer covers the respiratory epithelium of healthy people. The function of the airway mucus is to trap inhaled toxins and particles and expel them by mucociliary beating and coughing (Fahy and Dickey 2010; Zanin et al. 2016). Paradoxically, excessive mucus may cause coughing (Fontana and Lavorini 2006). Three steps are usually distinguished in a cough. The first step is inspiration, followed by a short compressive phase, and finally an explosive expiration accompanied by a characteristic sound. Secretions are removed in this violent expulsive phase, which is executed very quickly—around 0.4–0.5 s.
The complex puzzle of dietary silver nanoparticles, mucus and microbiota in the gut
Published in Journal of Toxicology and Environmental Health, Part B, 2020
Yuqiang Bi, Andrew K. Marcus, Hervé Robert, Rosa Krajmalnik-Brown, Bruce E. Rittmann, Paul Westerhoff, Marie-Hélène Ropers, Muriel Mercier-Bonin
The existence of bidirectional relationships between intestinal mucus and environmental pollutants/food additives was recently illustrated by Gillois et al. (2018). Due to its barrier properties, mucus may trap chemicals, thereby decreasing their toxicity to the host. Conversely, toxicants may affect mucus characteristics (e.g., number of goblet cells, thickness, mucin expression and composition) all along the GIT subsequently influencing gut and overall host health.