The Experts below are selected from a list of 390969 Experts worldwide ranked by ideXlab platform
Tiziano Marzo - One of the best experts on this subject based on the ideXlab platform.
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auranofin and its analogues show potent antimicrobial activity against multidrug resistant pathogens Structure activity relationships
ChemMedChem, 2018Co-Authors: Damiano Cirri, Tiziano Marzo, Simona Pollini, Marco Prato, Stefania Fallani, Maria Iris Cassetta, Andrea Novelli, Gian Maria Rossolini, Luigi MessoriAbstract:Due to the so-called "antibiotic resistance crisis" new antibacterial agents are urgently sought to treat multidrug-resistant pathogens. A group of gold- or silver-based complexes, of general formula [M(PEt3 )X] (with M=Au or Ag, and X=Cl, Br or I), alongside with three complexes bearing a positive or negative charge-[Au(PEt3 )2 ]Cl, K[Au(CN)2 ] and [Ag(PEt3 )2 ]NO3 -were prepared and comparatively tested with auranofin on a representative panel of pathogens including Gram-positive, Gram-negative and Candida strains. Interestingly, all the gold and silver complexes tested were active on Gram-positive strains, with the gold complexes having greater efficacy. The effects of the gold compounds were potentiated to a larger extent than silver compounds when tested in combination with a permeabilizing agent. A number of Relevant Structure-activity relationships emerged from the comparative analysis of the observed antibacterial profiles, shedding new light on the underlying molecular mechanisms of the action of these compounds.
Luigi Messori - One of the best experts on this subject based on the ideXlab platform.
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auranofin and its analogues show potent antimicrobial activity against multidrug resistant pathogens Structure activity relationships
ChemMedChem, 2018Co-Authors: Damiano Cirri, Tiziano Marzo, Simona Pollini, Marco Prato, Stefania Fallani, Maria Iris Cassetta, Andrea Novelli, Gian Maria Rossolini, Luigi MessoriAbstract:Due to the so-called "antibiotic resistance crisis" new antibacterial agents are urgently sought to treat multidrug-resistant pathogens. A group of gold- or silver-based complexes, of general formula [M(PEt3 )X] (with M=Au or Ag, and X=Cl, Br or I), alongside with three complexes bearing a positive or negative charge-[Au(PEt3 )2 ]Cl, K[Au(CN)2 ] and [Ag(PEt3 )2 ]NO3 -were prepared and comparatively tested with auranofin on a representative panel of pathogens including Gram-positive, Gram-negative and Candida strains. Interestingly, all the gold and silver complexes tested were active on Gram-positive strains, with the gold complexes having greater efficacy. The effects of the gold compounds were potentiated to a larger extent than silver compounds when tested in combination with a permeabilizing agent. A number of Relevant Structure-activity relationships emerged from the comparative analysis of the observed antibacterial profiles, shedding new light on the underlying molecular mechanisms of the action of these compounds.
Carmine Iodice - One of the best experts on this subject based on the ideXlab platform.
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biological effects of prenylated hydroquinones Structure activity relationship studies in antimicrobial brine shrimp and fish lethality assays
Journal of Natural Products, 1994Co-Authors: Salvatore De Rosa, Augusto Di Giulio, Carmine IodiceAbstract:: Twenty-three hydroquinone and quinone derivatives were assayed for antimicrobial effects and brine shrimp and fish lethalities, to establish Relevant Structure-activity relationships (SAR). Linear 2-prenyl-1,4-hydroquinones used for bioassay were obtained either by isolation from the sponge Ircinia spinosula or by synthesis. Corresponding quinones, as well as hydroquinones possessing saturated side-chains composed of one to eight isopentane units, were also synthesized and biologically evaluated. Terpenoid 1,4-benzoquinones displayed moderate antimicrobial activity against three microorganisms, SAR studies indicate the optimum length of the side-chain is in the range of five to fifteen carbon atoms.
Brian J Quiter - One of the best experts on this subject based on the ideXlab platform.
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modeling aerial gamma ray backgrounds using non negative matrix factorization
IEEE Transactions on Nuclear Science, 2020Co-Authors: Mark S Bandstra, Tenzing Joshi, K J Bilton, Andreas Zoglauer, Brian J QuiterAbstract:Airborne gamma-ray surveys are useful for many applications, ranging from geology and mining to public health and nuclear security. In all these contexts, the ability to decompose a measured spectrum into a linear combination of background source terms can provide useful insights into the data and lead to improvements in the techniques that use spectral energy windows. Multiple methods for the linear decomposition of spectra exist but are subject to various drawbacks, such as allowing negative photon fluxes or requiring detailed Monte Carlo modeling. We propose using non-negative matrix factorization (NMF) as a data-driven approach to spectral decomposition. Using aerial surveys that include flights over water, we demonstrate that the mathematical approach of NMF finds physically Relevant Structure in the aerial gamma-ray background, namely, that measured spectra can be expressed as the sum of nearby terrestrial emission, distant terrestrial emission, and radon and cosmic emission. These NMF background components are compared with the background components obtained by noise-adjusted singular value decomposition (NASVD), which contain negative photon fluxes and, thus, do not represent the emission spectra in as straightforward a way. Finally, we comment on the potential areas of research that are enabled by NMF decompositions, such as new approaches to spectral anomaly detection and data fusion.
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modeling aerial gamma ray backgrounds using non negative matrix factorization
arXiv: Instrumentation and Methods for Astrophysics, 2020Co-Authors: Mark S Bandstra, Tenzing Joshi, K J Bilton, Andreas Zoglauer, Brian J QuiterAbstract:Airborne gamma-ray surveys are useful for many applications, ranging from geology and mining to public health and nuclear security. In all these contexts, the ability to decompose a measured spectrum into a linear combination of background source terms can provide useful insights into the data and lead to improvements over techniques that use spectral energy windows. Multiple methods for the linear decomposition of spectra exist but are subject to various drawbacks, such as allowing negative photon fluxes or requiring detailed Monte Carlo modeling. We propose using Non-negative Matrix Factorization (NMF) as a data-driven approach to spectral decomposition. Using aerial surveys that include flights over water, we demonstrate that the mathematical approach of NMF finds physically Relevant Structure in aerial gamma-ray background, namely that measured spectra can be expressed as the sum of nearby terrestrial emission, distant terrestrial emission, and radon and cosmic emission. These NMF background components are compared to the background components obtained using Noise-Adjusted Singular Value Decomposition (NASVD), which contain negative photon fluxes and thus do not represent emission spectra in as straightforward a way. Finally, we comment on potential areas of research that are enabled by NMF decompositions, such as new approaches to spectral anomaly detection and data fusion.
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Modeling Aerial Gamma-Ray Backgrounds Using Non-negative Matrix Factorization
eScholarship University of California, 2020Co-Authors: Bandstra Ms, K J Bilton, Joshi Thy, Zoglauer A, Brian J QuiterAbstract:© 1963-2012 IEEE. Airborne gamma-ray surveys are useful for many applications, ranging from geology and mining to public health and nuclear security. In all these contexts, the ability to decompose a measured spectrum into a linear combination of background source terms can provide useful insights into the data and lead to improvements in the techniques that use spectral energy windows. Multiple methods for the linear decomposition of spectra exist but are subject to various drawbacks, such as allowing negative photon fluxes or requiring detailed Monte Carlo modeling. We propose using non-negative matrix factorization (NMF) as a data-driven approach to spectral decomposition. Using aerial surveys that include flights over water, we demonstrate that the mathematical approach of NMF finds physically Relevant Structure in the aerial gamma-ray background, namely, that measured spectra can be expressed as the sum of nearby terrestrial emission, distant terrestrial emission, and radon and cosmic emission. These NMF background components are compared with the background components obtained by noise-adjusted singular value decomposition (NASVD), which contain negative photon fluxes and, thus, do not represent the emission spectra in as straightforward a way. Finally, we comment on the potential areas of research that are enabled by NMF decompositions, such as new approaches to spectral anomaly detection and data fusion
Salvatore De Rosa - One of the best experts on this subject based on the ideXlab platform.
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biological effects of prenylated hydroquinones Structure activity relationship studies in antimicrobial brine shrimp and fish lethality assays
Journal of Natural Products, 1994Co-Authors: Salvatore De Rosa, Augusto Di Giulio, Carmine IodiceAbstract:: Twenty-three hydroquinone and quinone derivatives were assayed for antimicrobial effects and brine shrimp and fish lethalities, to establish Relevant Structure-activity relationships (SAR). Linear 2-prenyl-1,4-hydroquinones used for bioassay were obtained either by isolation from the sponge Ircinia spinosula or by synthesis. Corresponding quinones, as well as hydroquinones possessing saturated side-chains composed of one to eight isopentane units, were also synthesized and biologically evaluated. Terpenoid 1,4-benzoquinones displayed moderate antimicrobial activity against three microorganisms, SAR studies indicate the optimum length of the side-chain is in the range of five to fifteen carbon atoms.
