18 research outputs found

    IMI : global trends in myopia management attitudes and strategies in clinical practice : 2022 update

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    PURPOSE. Surveys in 2015 and 2019 identified a high level of eye care practitioner concern/activity about myopia, but the majority still prescribed single vision interventions to young myopes. This research aimed to provide updated information. METHODS. A self-administered, internet-based questionnaire was distributed in 13 languages, through professional bodies to eye care practitioners globally. The questions examined awareness of increasing myopia prevalence, perceived efficacy and adoption of available strategies, and reasons for not adopting specific strategies. RESULTS. Of the 3195 respondents, practitioners’ concern about the increasing frequency of pediatric myopia in their practices differed between continents (P < 0.001), being significantly higher in Asia (9.0 ± 1.5 of 10) than other continents (range 7.7–8.2; P ≤ 0.001). Overall, combination therapy was perceived by practitioners to be the most effective method of myopia control, followed by orthokeratology and pharmaceutical approaches. The least effective perceived methods were single vision distance undercorrection, spectacles and contact lenses, as well as bifocal spectacles. Practitioners rated their activity in myopia control between (6.6 ± 2.9 in South America to 7.9 ± 1.2/2.2 in Australasia and Asia). Single-vision spectacles are still the most prescribed option for progressing young myopia (32.2%), but this has decreased since 2019, and myopia control spectacles (15.2%), myopia control contact lenses (8.7%) and combination therapy (4.0%) are growing in popularity. CONCLUSIONS. More practitioners across the globe are practicing myopia control, but there are still significant differences between and within continents. Practitioners reported that embracing myopia control enhanced patient loyalty, increasing practice revenue and improving job satisfaction

    Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

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    Contains fulltext : 172380.pdf (publisher's version ) (Open Access

    Evidence For Inhibition Of Topoisomerase 1A By Gold(Iii) Macrocycles And Chelates Targeting Mycobacterium Tuberculosis And Mycobacterium Abscessus

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    Mycobacterium tuberculosis and the fast-growing species Mycobacterium abscessus are two important human pathogens causing persistent pulmonary infections that are difficult to cure and require long treatment times. The emergence of drug-resistant M. tuberculosis strains and the high level of intrinsic resistance of M. abscessus call for novel drug scaffolds that effectively target both pathogens. In this study, we evaluated the activity of bis(pyrrolide-imine) gold(III) macrocycles and chelates, originally designed as DNA intercalators capable of targeting human topoisomerase types I and II (Topo1 and Topo2), against M. abscessus and M. tuberculosis. We identified a total of 5 noncytotoxic compounds active against both mycobacterial pathogens under replicating in vitro conditions. We chose one of these hits, compound 14, for detailed analysis due to its potent bactericidal mode of inhibition and scalable synthesis. The clinical relevance of this compound was demonstrated by its ability to inhibit a panel of diverse M. tuberculosis and M. abscessus clinical isolates. Prompted by previous data suggesting that compound 14 may target topoisomerase/gyrase enzymes, we demonstrated that it lacked cross-resistance with fluoroquinolones, which target the M. tuberculosis gyrase. In vitro enzyme assays confirmed the potent activity of compound 14 against bacterial topoisomerase 1A (Topo1) enzymes but not gyrase. Novel scaffolds like compound 14 with potent, selective bactericidal activity against M. tuberculosis and M. abscessus that act on validated but underexploited targets like Topo1 represent a promising starting point for the development of novel therapeutics for infections by pathogenic mycobacteria

    (1R*,2S*)-N,N&amp;#8242;-Bis[(E)-1H-pyrrol-2-ylmethylidene]cyclohexane-1,2-diamine monohydrate

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    The title compound, C16H20N4&amp;#183;H2O, was synthesized from cis-1,2-diaminocyclohexane (a racemic mixture of the (1R,2S) and (1S,2R) enantiomers). The compound crystallized with two molecules (A and B) in the asymmetric unit with a single water solvent molecule per Schiff base molecule. Molecules A and B have similar conformations as illustrated by the least-squares-fit with an r.m.s. deviation of 0.242&amp;#8197;&amp;#197;. The molecules within the asymmetric unit are bridged by hydrogen bonds to the two water molecules, resulting in a heterotetramer. The water molecule acts as both a hydrogen-bond donor and acceptor. The pyrrole-imine units are not co-planar, making an angle of 73.9&amp;#8197;(3)&amp;#176; and 76.9&amp;#8197;(3)&amp;#176; in molecules A and B, respectively

    Evidence for Inhibition of Topoisomerase 1A by Gold(III) Macrocycles and Chelates Targeting \u3cem\u3eMycobacterium tuberculosis\u3c/em\u3e and \u3cem\u3eMycobacterium abscessus\u3c/em\u3e

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    Mycobacterium tuberculosis and the fast-growing species Mycobacterium abscessus are two important human pathogens causing persistent pulmonary infections that are difficult to cure and require long treatment times. The emergence of drug-resistant M. tuberculosis strains and the high level of intrinsic resistance of M. abscessus call for novel drug scaffolds that effectively target both pathogens. In this study, we evaluated the activity of bis(pyrrolide-imine) gold(III) macrocycles and chelates, originally designed as DNA intercalators capable of targeting human topoisomerase types I and II (Topo1 and Topo2), against M. abscessus and M. tuberculosis. We identified a total of 5 noncytotoxic compounds active against both mycobacterial pathogens under replicating in vitro conditions. We chose one of these hits, compound 14, for detailed analysis due to its potent bactericidal mode of inhibition and scalable synthesis. The clinical relevance of this compound was demonstrated by its ability to inhibit a panel of diverse M. tuberculosis and M. abscessus clinical isolates. Prompted by previous data suggesting that compound 14 may target topoisomerase/gyrase enzymes, we demonstrated that it lacked cross-resistance with fluoroquinolones, which target the M. tuberculosis gyrase. In vitro enzyme assays confirmed the potent activity of compound 14 against bacterial topoisomerase 1A (Topo1) enzymes but not gyrase. Novel scaffolds like compound 14 with potent, selective bactericidal activity against M. tuberculosis and M. abscessus that act on validated but underexploited targets like Topo1 represent a promising starting point for the development of novel therapeutics for infections by pathogenic mycobacteria

    Gold(III) Macrocycles: Nucleotide-Specific Unconventional Catalytic Inhibitors of Human Topoisomerase I

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    Topoisomerase IB (Top1) is a key eukaryotic nuclear enzyme that regulates the topology of DNA during replication and gene transcription. Anticancer drugs that block Top1 are either well-characterized interfacial poisons or lesser-known catalytic inhibitor compounds. Here we describe a new class of cytotoxic redox-stable cationic Au<sup>3+</sup> macrocycles which, through hierarchical cluster analysis of cytotoxicity data for the lead compound, <b>3</b>, were identified as either poisons or inhibitors of Top1. Two pivotal enzyme inhibition assays prove that the compounds are true catalytic inhibitors of Top1. Inhibition of human topoisomerase IIα (Top2α) by <b>3</b> was 2 orders of magnitude weaker than its inhibition of Top1, confirming that <b>3</b> is a type I-specific catalytic inhibitor. Importantly, Au<sup>3+</sup> is essential for both DNA intercalation and enzyme inhibition. Macromolecular simulations show that <b>3</b> intercalates directly at the 5′-TA-3′ dinucleotide sequence targeted by Top1 via crucial electrostatic interactions, which include π–π stacking and an Au···O contact involving a thymine carbonyl group, resolving the ambiguity of conventional (drug binds protein) vs unconventional (drug binds substrate) catalytic inhibition of the enzyme. Surface plasmon resonance studies confirm the molecular mechanism of action elucidated by the simulations

    Gold(III) Macrocycles: Nucleotide-Specific Unconventional Catalytic Inhibitors of Human Topoisomerase I

    No full text
    Topoisomerase IB (Top1) is a key eukaryotic nuclear enzyme that regulates the topology of DNA during replication and gene transcription. Anticancer drugs that block Top1 are either well-characterized interfacial poisons or lesser-known catalytic inhibitor compounds. Here we describe a new class of cytotoxic redox-stable cationic Au<sup>3+</sup> macrocycles which, through hierarchical cluster analysis of cytotoxicity data for the lead compound, <b>3</b>, were identified as either poisons or inhibitors of Top1. Two pivotal enzyme inhibition assays prove that the compounds are true catalytic inhibitors of Top1. Inhibition of human topoisomerase IIα (Top2α) by <b>3</b> was 2 orders of magnitude weaker than its inhibition of Top1, confirming that <b>3</b> is a type I-specific catalytic inhibitor. Importantly, Au<sup>3+</sup> is essential for both DNA intercalation and enzyme inhibition. Macromolecular simulations show that <b>3</b> intercalates directly at the 5′-TA-3′ dinucleotide sequence targeted by Top1 via crucial electrostatic interactions, which include π–π stacking and an Au···O contact involving a thymine carbonyl group, resolving the ambiguity of conventional (drug binds protein) vs unconventional (drug binds substrate) catalytic inhibition of the enzyme. Surface plasmon resonance studies confirm the molecular mechanism of action elucidated by the simulations

    Gold(III) Macrocycles: Nucleotide-Specific Unconventional Catalytic Inhibitors of Human Topoisomerase I

    No full text
    Topoisomerase IB (Top1) is a key eukaryotic nuclear enzyme that regulates the topology of DNA during replication and gene transcription. Anticancer drugs that block Top1 are either well-characterized interfacial poisons or lesser-known catalytic inhibitor compounds. Here we describe a new class of cytotoxic redox-stable cationic Au<sup>3+</sup> macrocycles which, through hierarchical cluster analysis of cytotoxicity data for the lead compound, <b>3</b>, were identified as either poisons or inhibitors of Top1. Two pivotal enzyme inhibition assays prove that the compounds are true catalytic inhibitors of Top1. Inhibition of human topoisomerase IIα (Top2α) by <b>3</b> was 2 orders of magnitude weaker than its inhibition of Top1, confirming that <b>3</b> is a type I-specific catalytic inhibitor. Importantly, Au<sup>3+</sup> is essential for both DNA intercalation and enzyme inhibition. Macromolecular simulations show that <b>3</b> intercalates directly at the 5′-TA-3′ dinucleotide sequence targeted by Top1 via crucial electrostatic interactions, which include π–π stacking and an Au···O contact involving a thymine carbonyl group, resolving the ambiguity of conventional (drug binds protein) vs unconventional (drug binds substrate) catalytic inhibition of the enzyme. Surface plasmon resonance studies confirm the molecular mechanism of action elucidated by the simulations

    Gold(III) Macrocycles: Nucleotide-Specific Unconventional Catalytic Inhibitors of Human Topoisomerase I

    No full text
    Topoisomerase IB (Top1) is a key eukaryotic nuclear enzyme that regulates the topology of DNA during replication and gene transcription. Anticancer drugs that block Top1 are either well-characterized interfacial poisons or lesser-known catalytic inhibitor compounds. Here we describe a new class of cytotoxic redox-stable cationic Au<sup>3+</sup> macrocycles which, through hierarchical cluster analysis of cytotoxicity data for the lead compound, <b>3</b>, were identified as either poisons or inhibitors of Top1. Two pivotal enzyme inhibition assays prove that the compounds are true catalytic inhibitors of Top1. Inhibition of human topoisomerase IIα (Top2α) by <b>3</b> was 2 orders of magnitude weaker than its inhibition of Top1, confirming that <b>3</b> is a type I-specific catalytic inhibitor. Importantly, Au<sup>3+</sup> is essential for both DNA intercalation and enzyme inhibition. Macromolecular simulations show that <b>3</b> intercalates directly at the 5′-TA-3′ dinucleotide sequence targeted by Top1 via crucial electrostatic interactions, which include π–π stacking and an Au···O contact involving a thymine carbonyl group, resolving the ambiguity of conventional (drug binds protein) vs unconventional (drug binds substrate) catalytic inhibition of the enzyme. Surface plasmon resonance studies confirm the molecular mechanism of action elucidated by the simulations
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