989 research outputs found
Copper(II) Complexes of Coumarin-Derived Schiff Bases and their anti-Candida Activity
The condensation of 7-amino-4-methyl-coumarin (1) with a number of substituted salicylaldehydes yielded a series of Schiff bases (2a–2k) in good yields. Subsequent reaction of these ligands with copper( II) acetate yielded Cu(II) complexes (3a–3k) and some were characterised using X-ray crystallography. All of the free ligands and their metal complexes were tested for their anti-Candida activity
Copper(II) complexes of coumarin-derived Schiff bases and their anti-Candida activity.
The condensation of 7-amino-4-methyl-coumarin (1) with a number of substituted salicylaldehydes
yielded a series of Schiff bases (2a–2k) in good yields. Subsequent reaction of these ligands with copper(
II) acetate yielded Cu(II) complexes (3a–3k) and some were characterised using X-ray crystallography.
All of the free ligands and their metal complexes were tested for their anti-Candida activity. A
number of the ligands and complexes exhibited anti-Candida activity comparable to that of the commercially
available antifungal drugs, ketoconazole and Amphotericin B
Silver(I) complexes of 9-anthracenecarboxylic acid and imidazoles: synthesis, structure and antimicrobial activity
[Ag2(9-aca)2] (1) (9-acaH = 9-anthracenecarboxylic acid) reacts with a series of imidazoles to give
[Ag(imidH)2.3(CH3CN)0.7](9-aca) (3), [Ag6(imidH)4(9-aca)6(MeOH)2] (4), {[Ag(1-Me-imid)2]2[Ag4(9-
aca)6]} (5), {[Ag(1-Bu-imid)2]2[Ag4(9-aca)6]} (6) and [Ag(apim)](9-aca)·H2O (7) (imidH = imidazole;
1-Me-imid = 1-methylimidazole; 1-Bu-imid = 1-butylimidazole; apim = 1-(3-aminopropyl)imidazole).
The mononuclear complex 3, hexanuclear 4–6, and polymeric 7, were all characterised using X-ray
crystallography. While many of the complexes possess excellent in vitro antifungal and antibacterial
activities they are, unanimously, more effective against fungal cells. The insect, Galleria mellonella, can
survive high doses of the Ag(I) complexes administered in vivo, and a number of the complexes offer
significant protection to larvae infected with a lethal dose of pathogenic Candida albicans cells
Water-soluble bis(1,10-phenanthroline) Octanedioate Cu2+ and Mn2+ Complexes with Unprecedented Nano and Picomolar in Vitro Cytotoxicity: Promising Leads for Chemotherapeutic Drug Development
Dinuclear CuII and MnII bis-phenanthroline octanedioate complexes exhibit rapid, unprecedented nano and picomolar in vitro cytotoxicity against colorectal cancer lines and are less toxic than cisplatin when examined in vivo. The complexes are potent generators of cellular reactive oxygen species, avid DNA binders and induce O2 dependent cleavage of DNA. The Cu(II) complex was found to have self-cleaving nuclease activity
Copper(II) and silver(I)‑1,10‑phenanthroline‑5,6‑dione complexes interact with double‑stranded DNA: further evidence of their apparent multi‑modal activity towards Pseudomonas aeruginosa
Tackling microbial resistance requires continuous efforts for the development of new molecules with novel mechanisms of action and potent antimicrobial activity. Our group has previously identified metal-based compounds, [Ag(1,10-phenanthroline-5,6-dione)2]ClO4 (Ag-phendione) and [Cu(1,10-phenanthroline-5,6-dione)3](ClO4)2.4H2O (Cu-phendione), with efficient antimicrobial action against multidrug-resistant species. Herein, we investigated the ability of Ag-phendione and Cu-phendione to bind with double-stranded DNA using a combination of in silico and in vitro approaches. Molecular docking revealed that both phendione derivatives can interact with the DNA by hydrogen bonding, hydrophobic and electrostatic interactions. Cu-phendione exhibited the highest binding affinity to either major (− 7.9 kcal/mol) or minor (− 7.2 kcal/mol) DNA grooves. In vitro competitive quenching assays involving duplex DNA with Hoechst 33258 or ethidium bromide demonstrated that Ag-phendione and Cu-phendione preferentially bind DNA in the minor grooves. The competitive ethidium bromide displacement technique revealed Cu-phendione has a higher binding affinity to DNA (Kapp = 2.55 × 106 M−1) than Ag-phendione (Kapp = 2.79 × 105 M−1) and phendione (Kapp = 1.33 × 105 M−1). Cu-phendione induced topoisomerase I-mediated DNA relaxation of supercoiled plasmid DNA. Moreover, Cu-phendione was able to induce oxidative DNA injuries with the addition of free radical scavengers inhibiting DNA damage. Ag-phendione and Cu-phendione avidly displaced propidium iodide bound to DNA in permeabilized Pseudomonas aeruginosa cells in a dose-dependent manner as judged by flow cytometry. The treatment of P. aeruginosa with bactericidal concentrations of Cu-phendione (15 µM) induced DNA fragmentation as visualized by either agarose gel or TUNEL assays. Altogether, these results highlight a possible novel DNA-targeted mechanism by which phendione-containing complexes, in part, elicit toxicity toward the multidrug-resistant pathogen P. aeruginosa
Miniature modular sensor for chemical species tomography with enhanced spatial resolution
The introduction of low/zero-carbon fuels in gas turbine engines poses challenges to the stability and efficiency of combustion processes. As a result, there is a growing demand for advanced imaging techniques that can provide enhanced spatial resolution to monitor and analyze the physiochemical parameters involved. Chemical Species Tomography (CST), utilizing multiple line-of-sight Laser Absorption Spectroscopy (LAS) measurements, has gained popularity in industrial applications due to its non-intrusive nature, robustness, and high sensitivity. Typically, existing CST sensors have few centimeters beam spacing and are highly customized for specific applications. Therefore, the limited beam spacing, and lack of generality pose challenges in terms of providing sufficient sampling and adaptability for wider application scenarios. To enhance the spatial resolution as well as improve the reconfiguration of the CST sensors, this paper proposes a miniature modular CST sensor with a 1cm beam spacing. The use of off-the-shelf components significantly reduces the cost of the system, making it more practical for industrial implementation. Experimental evaluation of the prototype sensor has been conducted for measurements of temperature and water vapor concentration. The results show consistent and accurate measurements, indicating good reliability of the sensor. The proposed miniature modular sensor offers increased flexibility and adaptability to the various CST systems, paving the way for its commercialization in industrial settings
"Women's rights, the European Court and Supranational Constitutionalism"
This analysis examines supranational constitutionalism in the European Union. In particular, the study focuses on the role of the European Court of Justice in the creation of women’s rights. I examine the interaction between the Court and member state governments in legal integration, and also the integral role that women’s advocates – both individual activists and groups – have played in the development of EU social provisions. The findings suggest that this litigation dynamic can have the effect of fueling the integration process by creating new rights that may empower social actors and EU organizations, with the ultimate effect of diminishing member state government control over the scope and direction of EU law. This study focuses specifically on gender equality law, yet provides a general framework for examining the case law in subsequent legal domains, with the purpose of providing a more nuanced understanding of supranational governance and constitutionalism
A fast sensor for non-intrusive measurement of concentration and temperature in turbine exhaust
Accurate and rapid measurement of water vapor concentration and temperature in the exhaust of gas turbine engines is critical for monitoring their health and operational performance. To monitor the two parameters simultaneously, a non-intrusive sensor based on tunable diode laser absorption spectroscopy is developed using 8 laser beams targeting 3 transitions of water vapor. The sensor has in situ validated on a commercial auxiliary power unit. Seven parallel laser beams at 5000.2 cm-1 are 6.3 mm spaced at the plume boundary to characterize the edge effect between hot exhaust plume and cold surrounding flow. One beam, operating at the dual wavenumbers of 7185.6 cm-1 and 7444.4 cm-1 penetrates the plume through centerline to measure temperature via ratio thermometry and then use this temperature information to obtain the concentration of water vapor. A temporal resolution of 4 milliseconds is achieved for the 8-beam measurement, enabling high-speed and simultaneous quantification of the edge effects and the plume parameters. Results indicate water vapor concentration and temperature in the exhaust measured by the developed sensor are highly consistent with the traditional benchmarks, e.g., extractive sampling and thermocouples, with a difference of 0.02% and 3°C, respectively. Enabled by its continuous millisecond-level measurements, the sensor, for the first time, reveals hidden engine behaviors and combustion dynamics that are unable to be observed by the traditional methods, thus facilitating next-generation real-time gas turbine engine control towards low emissions
CLIMB-COVID: continuous integration supporting decentralised sequencing for SARS-CoV-2 genomic surveillance.
Funder: Wellcome TrustIn response to the ongoing SARS-CoV-2 pandemic in the UK, the COVID-19 Genomics UK (COG-UK) consortium was formed to rapidly sequence SARS-CoV-2 genomes as part of a national-scale genomic surveillance strategy. The network consists of universities, academic institutes, regional sequencing centres and the four UK Public Health Agencies. We describe the development and deployment of CLIMB-COVID, an encompassing digital infrastructure to address the challenge of collecting and integrating both genomic sequencing data and sample-associated metadata produced across the COG-UK network
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