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Pharmacological Management of Parkinson’s Disease
Published in Sahab Uddin, Rashid Mamunur, Advances in Neuropharmacology, 2020
Newman Osafo, Samuel Obeng, David D. Obiri, Oduro K. Yeboah, Leslie B. Essel
Cabergoline is well absorbed when orally administration. The drug undergoes extensive hydrolysis in the liver leading to the breaking of the acylurea bond of the urea moiety and is excreted in the bile and feces. Its extremely long half-life is advantageous, as it alleviates the problem of “off” reactions and a once daily administration is favored (Andreotti et al., 1995).
Gene Delivery
Published in Danilo D. Lasic, LIPOSOMES in GENE DELIVERY, 2019
In addition to the possibilities discussed above, some systems were already tested in vivo. Conjugates of cationic polymer and targeting ligand may act as an efficient delivery vehicle for systemic application. Targeting of liver hepatocytes via internalizing an asialoglycoprotein receptor by covalent conjugates of polylysine and targeting molecule (asialorosomucoid) demonstrated therapeutic activity (see Chapter 13). Polylysine conjugated to transferrin was used to target neoplastic cells which exhibit this receptor because rapidly dividing cells require a high level of iron. Similarly, insulin conjugated to positively charged N-acylurea albumin was also used as a receptor-specific carrier to cells expressing insulin receptor. Macrophages can be targeted by macrophage-expressed lectins which bind mannose, glycans, galactose, or fucosyl-glycoconjugates (Monsigny et al., 1994).
Affinity Modification — Organic Chemistry
Published in Dmitri G. Knorre, Valentin V. Vlassov, Affinity Modification of Biopolymers, 1989
Dmitri G. Knorre, Valentin V. Vlassov
Nucleophile HX may be an amino, SH, or hydroxy group. The formation of N-acyl urea is interesting since it allows the reaction with carbodiimide for specific modification of carboxyl groups in proteins.
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
BCDI can also be used as a bifunctional crosslinker to directly crosslink adjacent HA chains. In this technique, the carboxyl functionality on the HA main chain is utilized under mildly acidic medium to form a stable HA acylurea with the biscarbodiimide on both ends in the absence of a nucleophile (such as amines) or any other polyanionic polysaccharide other than HA itself [39]. The reaction proceeds by protonation of the carbodiimide, followed by attack of the carboxylate anion on the carbon atom of the BCDI to form an O-acylisourea intermediate. In acidic medium, the intermediate then undergoes O-to-N migration to form the more stable N-acylurea depicted in Figure 1. This reaction is carried out in the presence of a pH buffer usually between pH 4.5 and 5.5. One of the specifications of this method is keeping the pH of the medium within the required range as carbodiimides are unstable at lower pH values while the reaction rate is diminished [40]. Since the rearrangements at both ends of the biscarbodiimide are non-concerted, the O-to-N migration can be incomplete which would result in a mixture of N-acylurea at both ends, a mixture one N-acylurea and one O-acylisourea at either end, and O-acylisourea at both ends.
Fumigant toxicity of three Satureja species on tomato leafminers, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)
Published in Toxin Reviews, 2021
Chemical control was considered as the first method of management against T. absoluta. The insecticides used against this pest have been very diverse including organophosphates, pyrethroids, cartap, thiocyclam, and chemicals with new sites of action such as abamectin, spinosad, fipronil, chlorantraniliprole, flubendiamide, tebufenozide, acylurea insect growth regulators and chlorfenapyr (Desneux et al. 2010, Khani et al. 2020, Kumar et al. 2020, Mohanny et al. 2020). Generally, the feeding behavior of larvae (leaf mining) causes problems in the chemical control effectiveness (Lietti et al. 2005). Moreover, resistance to insecticides may be the most important reason of control failure. The primary reports of insecticide resistance were seen in South American countries such as Chile, Brazil, and Argentina. In these countries, different levels of resistance to organophosphates (e.g. methamidophos), pyrethroids (e.g. permethrin and deltamethrin), cartap, and abamectin, have been evaluated (Salazar and Araya 1997, Siqueira et al. 2000, Lietti et al. 2005). In addition, resistance to pyrethroid, indoxacarb, diamide and spinosyn spinosad has been reported in South America and Europe (Silva et al. 2011, Guedes and Siqueira 2012, Gontijo et al. 2013, Roditakis et al. 2013, Campos et al. 2015, Roditakis et al. 2015). In addition to insecticide resistance which may cause control failure, insecticides have adverse effects on non-target organisms such as beneficial arthropods either through direct acute toxicity in short-term and/or sublethal effects in entire organism life (Martinou et al. 2014).
Overcoming multidrug resistance through targeting ABC transporters: lessons for drug discovery
Published in Expert Opinion on Drug Discovery, 2022
Mohammad Feyzizadeh, Ashkan Barfar, Zeinab Nouri, Muhammad Sarfraz, Parvin Zakeri-Milani, Hadi Valizadeh
A new set of derivatives having 5-cyano-6-phenyl pyrimidine structure was assessed for their inhibitory activity against ABC transporters. Among these derivatives, one molecule having an acylurea group exhibited the strongest activity in inverting resistance to PTX in colon adenocarcinoma cell line (SW620/AD300). Additional tests showed that the aforementioned compound increased intracellular concentration of PTX, disturbed ABCB1-facilitated Rh123 accretion and outflow, and particularly had no impact on CYP3A4 activity, which evades drug–drug interactions and substantial adverse effects. Furthermore, this compound meaningfully improved the cytotoxic activity of PTX against xenografted SW620/AD300 cells to mice without noticeable adverse events when given orally [114]. In another study, the common phenethyl tetrahydroisoquinoline group in the structure of third-generation chemosensitizers of P-gp and common active groups of BCRP modulators were connected by carboxamide linker. Also, the common pyrimidine aminobenzene group in TKIs was combined with the third-generation inhibitors chemical scaffold in order to get another series of compounds. Reversal potency of furan ring is stronger than that observed with thiophene ring. This kind of activity in methylbenzene groups is improved in benzene rings substituted with other groups, against either P-gp or BCRP. Molecular docking tests demonstrated a compound with pyrimidine ring interacting with P-gp in two separate hydrophobic parts and with BCRP in one hydrophobic region and also via a strong hydrogen bond. This compound raised the accretion of adriamycin (ADM) and mitoxantrone (MX) inside human leukemic K562/A02 cell line, signifying repressive impact on the activity of P-gp and BCRP transporters. More interestingly, coadministration of this compound considerably raised the intestinal absorption of PTX [115]. Using imatinib in combination with DOX in a pH-responsive liposome reversed resistance of MCF-7/ADR cells against DOX. Imatinib reverses MDR via reducing production of p-gp and BCRP transporters. This leads to higher levels of chemotherapeutic drug inside tumor cells [116].