Publications by authors named "Russell S Addison"

Metabolic chemical probes are small-molecule reagents that utilize naturally occurring biosynthetic enzymes for incorporation into biomolecules of interest. These reagents can be used to label, detect, and track important biological processes within living cells including protein synthesis, protein glycosylation, and nucleic acid proliferation. A limitation of current chemical probes, which have largely focused on mammalian cells, is that they often cannot be applied to other organisms due to metabolic differences.

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forms stable biofilms, providing a major barrier for multiple classes of antibiotics and severely impairing treatment of infected patients. The biofilm matrix of this Gram-negative bacterium is primarily composed of three major exopolysaccharides: alginate, Psl, and Pel. Here, we studied the antibiofilm properties of sponge-derived natural products ianthelliformisamines A-C and their combinations with clinically used antibiotics.

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Article Synopsis
  • * Researchers screened 7,616 extracts from marine invertebrates in Australian waters and identified 58 extracts that significantly reduced larval motility of the barber's pole worm, with a hit rate of about 0.8%.
  • * Most active extracts came from sponges, with a few from chordates and coral, and the study plans in-depth chemical analysis of prioritized samples to discover potential new nematocidal compounds.
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Chemical investigations of two specimens of the Australian crinoid afforded five new taurine-conjugated anthraquinones, comatulins A-E (-), together with 11 known marine natural products (-). The chemical structures of all the compounds were elucidated by detailed spectroscopic and spectrometric data analysis. The first X-ray crystal structure of a crinoid-derived acyl anthraquinone, rhodocomatulin 5,7-dimethyl ether (), is reported here.

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There is an urgent need to discover and develop new anthelmintics for the treatment of parasitic nematodes of veterinary importance to circumvent challenges linked to drug resistant parasites. Being one of the most diverse natural ecosystems, the marine environment represents a rich resource of novel chemical entities. This study investigated 2000 extracts from marine invertebrates, collected from Australian waters, for anthelmintic activity.

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Due to the widespread occurrence and spread of anthelmintic resistance, there is a need to develop new drugs against resistant parasitic nematodes of livestock animals. The Nobel Prize-winning discovery and development of the anti-parasitic drugs avermectin and artemisinin has renewed the interest in exploring natural products as anthelmintics. In the present study, we screened 7500 plant extracts for in vitro-activity against the barber's pole worm, Haemonchus contortus, a highly significant pathogen of ruminants.

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A sensitive high-performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) assay has been developed for the quantitative analysis of vardenafil in human plasma. Vardenafil and the internal standard, alprazolam, were extracted from 0.2 mL aliquots of alkalinized plasma by a single solvent extraction into hexane : dichloromethane.

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The two fixed-dose combinations of dihydroartemisinin and piperaquine (Artekin and Arterakine) were found to be bioinequivalent in healthy Vietnamese subjects. However, because the peak plasma concentrations and areas under the concentration-time curves of dihydroartemisinin and piperaquine were only marginally different between the two formulations, similar therapeutic efficacies are expected in the treatment of malaria infections.

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Lamotrigine concentrations were measured simultaneously (as far as was feasible) in stimulated and unstimulated saliva samples, and in plasma, from seven adult volunteers over a 32 h period following a single 50 mg dose of the drug, and in 20 children and adolescents during the course of routine antiepileptic therapy. In individuals there was a close correlation between the measurements at least 2 h after ingestion of the drug. Concentrations in stimulated and unstimulated saliva were similar; the stimulation produced little change in the saliva secretion rate.

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Article Synopsis
  • PI-88 is a mixture of sulfated oligosaccharides that inhibits heparanase and angiogenesis, showing potential for treating advanced solid tumors.
  • In a study involving 42 patients, the maximum tolerated dose of PI-88 was determined to be 250 mg/d, with dose-limiting toxicity mainly from thrombocytopenia and pulmonary embolism.
  • The drug was well tolerated overall, and one patient with melanoma saw a significant response lasting over 50 months, suggesting further evaluation in phase II trials is warranted.
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  • PI-88 is a mix of highly sulfated oligosaccharides being tested for its anticancer effects and other biological activities in cancer patients.
  • Researchers created analogues with a pentasaccharide backbone to better understand the structure and function of these compounds.
  • All analogues showed the ability to inhibit heparanase and block herpes simplex virus spread, with one derivative being cleared more slowly from the body, suggesting potential for longer exposure in treatment.*
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