A novel dual-imaging cisplatin-carrying molecular cargo capable of performing simultaneous optical and MR imaging is reported herein. This long-lasting MRI contrast agent (r relaxivity of 23.4 mMs at 3T, 25 C) is a photo-activated cisplatin prodrug () which enables real-time monitoring of anti-cancer efficacy.
View Article and Find Full Text PDFA unique, dual-function, photoactivatable anticancer prodrug, RuEuL, has been tailored that features a ruthenium(II) complex linked to a cyclen-europium chelate via a π-conjugated bridge. Under irradiation at 488 nm, the dark-inactive prodrug undergoes photodissociation, releasing the DNA-damaging ruthenium species. Under evaluation-window irradiation (λ = one-photon 350 nm or two-photon 700 nm), the drug delivery process can be quantitatively monitored in real-time because of the long-lived red europium emission.
View Article and Find Full Text PDFBisphenol A (BPA) glucuronide and sulfate conjugates are major products of Phase II metabolism of BPA in humans. In the past, their determination in body fluids usually involves tedious enzymatic hydrolysis and multiresidual analysis. The recent availability of authentic standards of these conjugates enables our better understand of the human metabolism of BPA and the distribution of their metabolites in body fluids.
View Article and Find Full Text PDFHydroxylated- and methoxylated- polybrominated diphenyl ethers (OH-PBDEs and MeO-PBDEs) are more toxic than PBDEs and occur widely in the marine environment, and yet their origins remain controversial. In this study, four species of microalgae (Isochrysis galbana, Prorocentrum minimum, Skeletonema grethae and Thalassiosira pseudonana) were exposed to BDE-47, which is synthetic and is the predominant congener of PBDEs in the environment. By chemical analysis after incubation of 2 to 6 days, the efficiency of uptake of BDE-47 and, more importantly, the potential of undergoing biotransformation to form OH-PBDEs and MeO-PBDEs by the microalgae were investigated.
View Article and Find Full Text PDF3,3',5,5'-Tetrabromobisphenol-A (TBBPA) is an important brominated flame retardant in epoxy, vinyl esters and polycarbonate resins. Previous studies have already shown the occurrence of its Phase II metabolites, TBBPA-glucuronide and sulfate conjugates, in human urine, after oral administration of TBBPA. The main objective of this work is to examine correlations among level of TBBPA in human blood and those of its Phase II metabolites in human urine.
View Article and Find Full Text PDFHydroxylated polybrominated diphenyl ethers (OH-PBDEs) are attracting more and more attention for the neurodevelopment toxicity effects. We evaluated the concentrations of 15 individual OH-PBDEs and 3 bromophenol (BRP) congeners in 30 mother-newborn paired placenta, breast milk, fetal cord blood, and neonatal urine samples collected from South China. The geometric mean (GM) concentrations of ∑OH-PBDEs were 37.
View Article and Find Full Text PDFOne possible source of urinary bromophenol (BP) glucuronide and sulfate conjugates in mammalian animal models and humans is polybromodiphenyl ethers (PBDEs), a group of additive flame-retardants found ubiquitously in the environment. In order to study the correlation between levels of PBDEs in human blood plasma and those of the corresponding BP-conjugates in human urine, concentrations of 17 BDE congeners, 22 OH-BDE and 13 MeO-BDE metabolites, and 3 BPs in plasma collected from 100 voluntary donors in Hong Kong were measured by gas chromatograph tandem mass spectrometry (GC-MS). Geometric mean concentration of ΣPBDEs, ΣOH-BDEs, ΣMeO-BDEs and ΣBPs in human plasma were 4.
View Article and Find Full Text PDFBromophenol glucuronide and sulfate conjugates have been reported to be products of mammalian metabolism of polybrominated diphenyl ethers (PBDEs), a group of additive flame-retardants found ubiquitously in the environment. In order to explore their occurrence in human urine, four water-soluble bromophenol conjugates, namely, 2,4-dibromophenyl glucuronide, 2,4,6-tribromophenyl glucuronide, 2,4-dibromophenyl sulfate, and 2,4,6-tribromophenyl sulfate, were synthesized, purified, and characterized. An analytical protocol using solid-phase extraction and ion-paired liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS) quantification has been developed for the direct and simultaneous determination of these glucuronide and sulfate conjugates in human urine samples.
View Article and Find Full Text PDFHydroxylated (OH-) and methoxylated (MeO-) polybrominated diphenyl ethers (PBDE) are suspected endocrine disruptors. Little is known about the accumulation or sources of these chemicals in tissues of humans, particularly those residing in Hong Kong, which is one of the most densely populated cities in the world. Seven MeO-BDEs, fifteen OH-BDEs and three bromophenols (BRPs) were analyzed in blood plasma of 116 humans that had been collected by the Hong Kong Red Cross.
View Article and Find Full Text PDFHigh concentrations of polybrominated diphenyl ethers (PBDEs) and their structural analogues (such as methoxylated (MeO) and hydroxylated (OH) PBDEs) had been observed in environmental samples and human tissues. This study evaluated the occurrence, potential source and human exposure of these organobrominated compounds via market fish consumption in Hong Kong. The contamination of 22 PBDEs, 7 MeO-BDEs, 15 OH-BDEs and 3 bromophenols (BRPs) were analyzed in 20 fish species (279 samples).
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