Publications by authors named "Joseph I Ambrus"

Article Synopsis
  • The study identifies dansylcadaverine as a moderate inhibitor of dynamin I (dynI) GTPase activity, affecting clathrin-mediated endocytosis in U2OS cells.
  • A new class of inhibitors, termed Sulfonadyns™, showed enhanced dynI inhibition with certain chemical modifications, notably the addition of a terminal cinnamyl group.
  • The most effective compound, Sulfonadyn-47, demonstrated significant anti-seizure effects in animal tests, comparable to established medications, suggesting potential for new anti-seizure drugs targeting dynamin.
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Formation of highly possessive antitermination complexes is crucial for the efficient transcription of stable RNA in all bacteria. A key step in the formation of these complexes is the protein-protein interaction (PPI) between N-utilisation substances (Nus) B and E and thus this PPI offers a novel target for a new antibiotic class. A pharmacophore developed via a secondary structure epitope approach was utilised to perform an in silico screen of the mini-Maybridge library (56,000 compounds) which identified 25 hits of which five compounds were synthetically tractable leads.

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The α4β2 nicotinic acetylcholine receptors (nAChRs) are widely expressed in the brain and are implicated in a variety of physiological processes. There are two stoichiometries of the α4β2 nAChR, (α4)2(β2)3 and (α4)3(β2)2, with different sensitivities to acetylcholine (ACh), but their pharmacological profiles are not fully understood. Methyllycaconitine (MLA) is known to be an antagonist of nAChRs.

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Background: Effective control of the use of anabolic-androgenic steroids (AASs) in animal sports is essential in order to ensure both animal welfare and integrity. In order to better police their use in Australian and New Zealand greyhound racing, thorough metabolic studies have been carried out on a range of registered human and veterinary AASs available in the region.

Results: Canine metabolic data are presented for the AASs boldenone, danazol, ethylestrenol, mesterolone, methandriol, nandrolone and norethandrolone.

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The 3-methylmaleimide congeners of the natural product methyllycaconitine (MLA) and an analogue covalently attach to functional cysteine mutants of the α7 nicotinic acetylcholine receptor (nAChR).

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Neuronal nicotinic acetylcholine receptors (nAChR) are ligand gated ion channels that mediate fast synaptic transmission. Methyllycaconitine (MLA) is a selective and potent antagonist of the α7 nAChR, and its anthranilate ester side-chain is important for its activity. Here we report the influence of structure on nAChR inhibition for a series of novel MLA analogs, incorporating either an alcohol or anthranilate ester side-chain to an azabicyclic or azatricyclic core against rat α7, α4β2, and α3β4 nAChRs expressed in Xenopus oocytes.

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The synthesis of 22 2-aryl-1H-indoles, including 12 new compounds, has been achieved via Pd- or Rh-mediated methodologies, or selective electrophilic substitution. All three methods were based on elaborations from simple indole precursors. SAR studies on these indoles and 2-phenyl-1H-indole in Staphylococcus aureus as NorA efflux pump inhibitors indicated 5-nitro-2-(3-methoxycarbonyl)phenyl-1H-indole was a slightly more potent inhibitor than the lead INF55.

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This review collates and analyses recent work done on dual action approaches to tackling the mounting health problem of resistance by human pathogenic bacteria to antibacterial agents. In particular the areas reviewed include the use of two drugs in combination, dual action prodrugs, and dual action drugs (or hybrid drugs).

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