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Lifestyle and Diet
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Polycyclic aromatic hydrocarbons (PAHs) are complex benzenoid compounds formed during incomplete combustion (196). The major sources of PAHs include domestic activities such as wood burning, frying, and barbecuing, as well as external origins like road traffic, fuel combustion in industry, forest fires, and more. Exposure to PAH-containing substances increases the risk of cancer in humans (196). The carcinogenicity of PAHs depends on the different chemical structure of the molecule. Fluoranthene is an important volatile PAH because it occurs at high levels in ambient air and because it has demonstrated carcinogenic property in certain test systems (196). Phenanthrene, anthracene, and pyrene also belong to PAHs and have carcinogenic property (196).
Antihypertensive effects of oriental drugs in human and SHR
Published in H. Saito, Y. Yamori, M. Minami, S.H. Parvez, New Advances in SHR Research –, 2020
Hideaki Higashino, Aritomo Suzuki, Koichiro Komai
I.c: The UV spectrum showed absorption by benzenoid (280 nm) and C=0 and/or NH2 (325 nm) groups. The IR spectrum showed absorption by the -OH (3,300 cm-1), -C=0, -CHO, -COOH (1,700 cm-1) groups and hetero ring (1,550 cm-1). These data suggested that I.c. fraction contained phenol carboxylic acids, cumaline and some alkaloids.
X-Ray, MRI, and Ultrasound Agents Basic Principles
Published in George C. Kagadis, Nancy L. Ford, Dimitrios N. Karnabatidis, George K. Loudos, Handbook of Small Animal Imaging, 2018
Michael F. Tweedle, Krishan Kumar, Michael V. Knopp
XRCAs have progressed to an incredibly high state of development over 100+ years, involving hundreds of researchers and hundreds of millions of dollars spent on their development. Most of the research that produced the currently used nonionic molecules was done within companies, but at this point, very little laboratory research is being done toward new molecular types in industry or academia. The most significant problem in the field is the very rare, deadly, and largely unpredictable anaphylactoid reactions. Animal models do not well mimic the human reactions, although hyperimmune rats have been used (Lasser et al. 1995). Any attempt to create a new XRCA of the iodinated benzenoid type would require a highly significant advance to justify the probable $200–$300 million to develop a commercial example (Nunn 2006). The reasons for the high cost are fourfold: (1) the existing CA are extremely well refined; (2) manufacturing plants must be extremely large capacity to serve 1000-ton annual markets; (3) each clinical indication must be separately proven to be effectively dealt with by a new contrast agent; and (4) the anaphylactoid reactions have no really well-validated animal model and are so rare that many thousands of patients would need to be screened to prove an advantage, which seems unlikely for any but a genuinely new structure. A new structure, for example, a heavy metal chelate, would require considerable work to refine to even the level of acute tolerance of the XRCA (see in the following) and would then require all of the aforementioned hurdles be overcome before a successful candidate could be imagined. There is an ancillary possibility for improving outcomes if an in vitro skin, blood, genetic, or other rapid test can be developed that predicts the serious adverse events, but so far none has appeared, other than older pilot studies (Eaton et al. 1988).
Characterization and initial demonstration of in vivo efficacy of a novel heat-activated metalloenediyne anti-cancer agent
Published in International Journal of Hyperthermia, 2022
Joy Garrett, Erin Metzger, Mark W. Dewhirst, Karen E. Pollok, John J. Turchi, Isabelle C. Le Poole, Kira Couch, Logan Lew, Anthony Sinn, Jeffrey M. Zaleski, Joseph R. Dynlacht
Enediynes are a class of natural products that were first recognized for their potent anti-tumor activities in the late 1980s. Since then, several derivatives have been synthesized, but common to all enediynes are two acetylenic groups conjugated to a double bond commonly situated within a nine- or ten-membered ring [1]. It is this uniquely strained structure that confers the cytotoxic tendencies of these compounds, as an appropriate chemical or physical trigger will induce the enediyne core to undergo Bergman cyclization. This cycloaromatization results in the production of a benzenoid 1,4-diradical intermediate that may go on to abstract H-atoms from DNA, resulting in strand breakage. While the DNA-damaging aspects of enediynes are tantalizing, their clinical utility has been limited due to challenges in controlling the initiation of diradical formation; the mild activation temperatures for enediyne cyclization (generally less than 37 °C) lead to toxicity. Combined with difficulties of synthetic accessibility, these factors discouraged their further development.
Identification of a dual TAOK1 and MAP4K5 inhibitor using a structure-based virtual screening approach
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2021
Min-Wu Chao, Tony Eight Lin, Wei-Chun HuangFu, Chao-Di Chang, Huang-Ju Tu, Liang-Chieh Chen, Shih-Chung Yen, Tzu-Ying Sung, Wei-Jan Huang, Chia-Ron Yang, Shiow-Lin Pan, Kai-Cheng Hsu
Compound 2 forms hydrogen bonds with residues M75, E76 and C78 in MAP4K5 with its S1 sub-structure, pteridine-2,4-diamine (Figure 3(B)). The hinge residue C78 forms a hydrogen bond with the cyclic nitrogen. Residues M75 and E76 form hydrogen bonds with the amino group, which acts as a hydrogen donor for the two residues. Hydrophobic interactions by residues V15, A28, Y77, C78 and A128 sandwich the S1 sub-structure (Figure 3(B)). Attached to the sub-structure S1 are two phenol moieties that form sub-structures S2 and S3 (Figure 3(B)). One phenol group forms a hydrogen bond with residue S9, while the other creates a hydrogen bond with residues K30 and D139. Phenols consist of hydrophobic benzenoid rings. As a result, the two phenol moieties also form hydrophobic interactions with a number of residues, such as V15, L128, and A138 (Figure 3(B)).
Designing safer analgesics: a focus on μ-opioid receptor pathways
Published in Expert Opinion on Drug Discovery, 2018
Joseph V. Pergolizzi, Jo Ann LeQuang, Robert Taylor, Michael H. Ossipov, Daniel Colucci, Robert B. Raffa
Cebranopadol, currently under development, has been called a first-in-class novel analgesic of the benzenoid class [16]. It is an agonist at µ- and to a lesser extent the other opioid receptors and NOP [16]. The mixed µ/NOP receptor action may produce a synergistic enhancement of analgesic effect as suggested in preclinical studies (although the cellular mechanism of the synergy is not known) [17–21]. In addition, cebranopadol might be a G-protein-biased agonist at µ- and NOP-receptors [16]. ‘Biased ligand’ refers to agonists that, upon binding to and activating a G protein-coupled receptor, preferentially activate the G-protein-linked effector pathway over the β-arrestin pathway. This biased receptor activation has been proposed to be associated with lower risk of respiratory depression, and possibly other adverse effects. [4]