Search results for "GOLD"

A Colorimetric Membrane-Based Sensor with Improved Selectivity towards Amphetamine

2021

Due to their simplicity, speed and low cost, chemical spot tests are increasingly demanded for the presumptive identification of illicit drugs in a variety of contexts such as point-of-care assistance or prosecution of drug trafficking. However, most of the colorimetric reactions used in these tests are, at best, drug class selective. Therefore, the development of tests based on chemical reactions with improved discrimination power is of great interest. In this work, we propose a new colorimetric assay for amphetamine (AMP) based on its reaction with solutions of alkaline gold bromide to form an insoluble yellow–orange derivative. The resulting suspensions are then filtered onto nylon membr…

Selected cytotoxic gold compounds cause significant inhibition of 20S proteasome catalytic activities

2014

Abstract Six structurally diverse cytotoxic gold compounds are reported to cause profound and differential inhibition of the three main catalytic activities of purified 20S proteasome whilst auranofin , an established gold(I) drug in clinical use, is nearly ineffective. In particular, the gold(I) complex [( pbiH ) Au ( PPh 3 )] PF 6 , turns out to be the most potent inhibitor of all three enzyme activities with sub-micromolar IC 50 values. The present results further support the view that proteasome inhibition may play a major – yet not exclusive – role in the cytotoxic actions of gold based anticancer agents.

Alternative to oral dicoumarin anticoagulants: Considerations in dental care

2013

Introduction: For over 50 years, vitamin K antagonists such as warfarin (Aldocumar®) and acenocoumarol (Sintrom®) have been the gold standard for reducing the risk of cerebrovascular events. In the last 5 years alternative anticoagulants have been evaluated that act directly upon a concrete target within the coagulation cascade, thereby affording a more predictable anticoagulant effect. The present study offers an update on the new oral anticoagulants and reviews the implications referred to the dental care of patients administered these substances. Material and methods: An exhaustive PubMed-Medline and Cochrane Library search was made of the main alternatives to conventional oral anticoagu…

Sealing ability of five different retrograde filling materials.

1996

The sealing ability of Amalgam, Harvard-Cement, Diaket, gold-leaf, and Ketac-Endo as retrofilling materials was investigated. Paper cones were fixed with Harvard-Cement in the instrumented roots of 100 extracted human incisors. Apicectomy was performed and a 2-mm-deep retrograde cavity was prepared. Teeth were assigned to five groups (n = 20); each group received a different filling material. Surfaces of the roots were isolated with nail polish. Teeth, were stored in 1% methylene blue dye for 72 h. Roots were sectioned, and the depth of dye penetration was evaluated through a stereomicroscope. Retrofills with Ketac-Endo showed significantly less leakage compared with amalgam. There was no s…

Laser-assisted nuclear decay spectroscopy of Au-176,Au-177,Au-179

2021

ispartof: PHYSICAL REVIEW C vol:104 issue:2 status: published

Silver ions mediated photochemical synthesis of water soluble gold nanoparticles with control over size and morphology

2007

La imagen de la Concha de Oro en los impresos de la Edad Moderna

2020

For centuries, an image commonly associated with Santiago de Compostela (the shell) has accompanied the city of Palermo as well. Since the classical tradition and medieval literature, and then during the Renaissance and Baroque age, this symbol has been connected with other urban symbols (the rivers, the eagle and trhe Genius of Palermo), thus contributing to its historical identity, although in a rather idealistic form. Therefore, the expression «Golden Shell» has been used repeatedly in a large number of books printed during the Modern Age, with multiple meanings. The main purpose was to show those attributes linked with the city's landscape (wealth and beauty) within a specific political…

Soil is the best testifier of the diachronous dawn of the Anthropocene

2021

Humans act at worldwide scale as a growing geomorphic agent since mid‐Holocene (8,200–4,200 y BP) through the pervasive impacts of domestication, deforestation, agriculture, urbanization, and mining. The concept of Anthropocene has been introduced exactly to indicate the timespan in which humans have joined with other natural forces in impacting the outermost shell of the planet and the biosphere. Soils, which are the Earth's skin, are sensitive archives of any major human‐induced local to global change. Especially when buried, soils can permanently preserve the primordial traces of a significant impact of man on the environment, which occurred at different times and rates in different area…

Hydrophobic pocket targeting probes for enteroviruses

2015

Visualization and tracking of viruses without compromising their functionality is crucial in order to understand virus targeting to cells and tissues, and to understand the subsequent subcellular steps leading to virus uncoating and replication. Enteroviruses are important human pathogens causing a vast number of acute infections, and are also suggested to contribute to the development of chronic diseases like type I diabetes. Here, we demonstrate a novel method to target site-specifically the hydrophobic pocket of enteroviruses. A probe, a derivative of Pleconaril, was developed and conjugated to various labels that enabled the visualization of enteroviruses under light and electron micros…

A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts

2020

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in‐house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV…