Human mercaptolactate-cysteine disulfiduria (MCDU) was first recognized and reported in 1968. Most cases of MCDU are associated with mental retardation, while the pathogenesis remains unknown. To investigate it, we generated homozygous 3-mercaptopyruvate sulfurtransferase (MST: EC 2.8.1.2) knockout (KO) mice using C57BL/6 embryonic stem cells as an animal model. The MST-KO mice showed significa...

Epidemiological studies suggest potent anticancer effects of tea catechins. Previously, we have reported (I. Naasani et al., Biochem. Biophys. Res. Commun., 249: 391–396, 1998) that epigallocatechin gallate (EGCG), a major tea catechin, strongly and directly inhibits telomerase, a ribonucleoprotein that maintains telomeres and has been implicated in tumorigenesis. Here, we describe newly synthe...

The nanomechanical properties of solvent-cast polymer thin films have been investigated using PeakForceTM Quantitative Nanomechanical Mapping. The samples consisted of films of polystyrene (PS) and poly(methyl methacrylate) (PMMA) obtained after the dewetting of toluene solution on a polymeric brush layer. Additionally, we have probed the mechanical properties of poly(styrene-b-methyl methacryl...

This study reports the first attempt to employ a potassium–graphite intercalation compound (KC24) as an initiator for one-pot synthesis of multi-block copolymer. The results obtained show that KC24 successfully initiated copolymerization, leading copolymer consisting poly(styrene), poly(methyl methacrylate) and poly(ethylene oxide) blocks. When all three comonomers were introduced simultaneousl...

Monosodium titanates (MST) are a relatively novel form of particulate titanium dioxide that have been proposed for biological use as metal sorbents or delivery agents, most recently calcium (II). In these roles, the toxicity of the titanate or its metal complex is crucial to its biological utility. The aim of this study was to determine the cytotoxicity of MST and MST-calcium complexes with MC3...

BACKGROUND Previous studies have suggested that occupational exposure to styrene is associated with increased serum levels of the anterior pituitary hormone prolactin (PRL). AIMS To test the hypotheses that: (1) the effect of styrene exposure on PRL secretion is an acute effect, not a subchronic or chronic effect; (2) blood styrene, as a measure of absorbed dose, is a stronger predictor of se...

ALDH2 is involved in the metabolism of styrene, a widely used industrial material, but no data are available regarding the influence of this enzyme on the metabolic fate as well as toxic effects of this chemical. In this study, we recruited 329 workers occupationally exposed to styrene and 152 unexposed controls. DNA strand breaks, DNA-base oxidation in leukocytes and urinary 8-hydroxydeoxyguan...

aim : this study reports the prevalence observed in minimal standard terminology (mst) writing in three hospital endoscopy centers in tehran. background : in 1991 european association decided to recognize the minimal essential terms for preparing the endoscopy reports using computer software. these activities have led to the arrangement of mst. patients and methods : the cross - sectional study...

Ionomers containing sodium 4-styrene sulfonate (4SS) and poly(ethylene glycol) methyl ether acrylate (PEGA) were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. The polymerization was mediated by 1-phenylethyl dithiobenzoate chain transfer agent in a dimethylformamide/water solvent system. Well-defined copolymers of pPEGA-co-4SS were produced with molecula...

Dispersions of isolated single wall carbon nanotubes (SWNTs) in pure organic solvents can usually be prepared only at low concentrations (∼0.01-0.02 g/L). Here, we use poly(vinylpyrrolidone) as a dispersant for unfunctionalized SWNTs in N-methyl-2-pyrrolidone and achieve concentrations of up to ∼0.16 g/L. Such dispersions remain stable by visual inspection for at least 1 year after preparation....