Sulforaphane Attenuates H2O2-induced Oxidant Stress in Human Trabecular Meshwork Cells (HTMCs) via the Phosphatidylinositol 3-Kinase (PI3K)/Serine/Threonine Kinase (Akt)-Mediated Factor-E2-Related Factor 2 (Nrf2) Signaling Activation.

BACKGROUND The aim of this study was to investigate whether and how sulforaphane (SFN), a novel promising nuclear factor-E2-related factor 2 (Nrf2) activator, exerted antioxidative stress through activating Nrf2 signaling. MATERIAL AND METHODS Cultured human trabecular meshwork cells (HTMCs) were treated with SFN for 6 hours after establishing the oxidative stress model by hydrogen peroxide (H2O2). The cell viability, the level of intercellular reactive oxygen species (ROS), and the apoptosis rate were observed using various kits. In addition, the gene and protein expression of Nrf2 and the phase II antioxidative enzymes were determined by performing qRT-PCR and western blotting. RESULTS In H2O2-treated HTMCs, SFN protected HTMCs from oxidative stress damage and decreased the intracellular ROS accumulation, thus inhibiting cell apoptosis. SFN also increased the gene and protein expression of phase II antioxidative enzymes such as NAD(P)H: quinone oxidoreductase 1 (NQO-1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC), and glutamate-cysteine ligase modifier subunit (GCLM) by Nrf2-dependent pathway. Furthermore, investigations of the pathway showed that HTMCs pretreated with LY294002, an inhibitor of phosphatidylinositol 3-kinase (PI3K), downregulated the expression of phase II antioxidative enzymes, partly. CONCLUSIONS These results indicated a novel application for SFN in attenuating H2O2-induced oxidative stress in HTMCs through activating PI3K/Akt/Nrf2 signaling pathway.

Determination of four main components of gentamicin in animal tissues after solid-phase extraction by high-performance liquid chromatography/tandem mass spectrometry.

RATIONALE: An analytical method for gentamicin in animal tissues was developed and validated. An alkaline mobile phase with an HPH C8 column was selected so that all the four gentamicin components were retained and eluted without using fluorinated ion-pairing reagents. METHODS: The method is sufficiently sensitive and highly selective, using a strong cation-exchange solid-phase extraction cartridge (PCX) to clean up the samples. Different types of solid-phase extraction columns and membranes were considered to obtain a high recovery. The method was validated on spiking samples, recovery, inter- and intra-assay variation, to ensure its accuracy and precision. RESULTS: The LOQ (S/N ≥ 10) for gentamicin in goat meat, liver, kidney and adipose tissue was 25, 50, 30 and 30 ng/g, respectively; the LOD (S/N ≥ 3) was 5, 10, 10 and 10 ng/g, respectively. The recoveries were between 88% and 106%. The method in all animal tissues was calibrated from 10 to 1000 µg/L in the matrix-assisted standard solution. CONCLUSIONS: The novelty of this method is that the commonly used fluorinated ion-pairing reagent was not used in the mobile phase in our analysis, greatly reducing the contamination of the ESI source in negative mode. Moreover, the four gentamicin components were clearly separated via chromatographic separation.

Inhibition of Glucose-6-Phosphate Dehydrogenase Could Enhance 1,4-Benzoquinone-Induced Oxidative Damage in K562 Cells.

Benzene is a chemical contaminant widespread in industrial and living environments. The oxidative metabolites of benzene induce toxicity involving oxidative damage. Protecting cells and cell membranes from oxidative damage, glucose-6-phosphate dehydrogenase (G6PD) maintains the reduced state of glutathione (GSH). This study aims to investigate whether the downregulation of G6PD in K562 cell line can influence the oxidative toxicity induced by 1,4-benzoquinone (BQ). G6PD was inhibited in K562 cell line transfected with the specific siRNA of G6PD gene. An empty vector was transfected in the control group. Results revealed that G6PD was significantly upregulated in the control cells and in the cells with inhibited G6PD after they were exposed to BQ. The NADPH/NADP and GSH/GSSG ratio were significantly lower in the cells with inhibited G6PD than in the control cells at the same BQ concentration. The relative reactive oxygen species (ROS) level and DNA oxidative damage were significantly increased in the cell line with inhibited G6PD. The apoptotic rate and G2 phase arrest were also significantly higher in the cells with inhibited G6PD and exposed to BQ than in the control cells. Our results suggested that G6PD inhibition could reduce GSH activity and alleviate oxidative damage. G6PD deficiency is also a possible susceptible risk factor of benzene exposure.

Simultaneous determination of p-arsanilic acid and roxarsone in feed by liquid chromatography-hydride generation online coupled with atomic fluorescence spectrometry.

A novel, simple and sensitive liquid chromatography-hydride generation online coupled with atomic fluorescence spectrometry (LC-HG-AFS) method was developed for simultaneous determination of p-arsanilic acid (p-ASA) and roxarsone in feed. 20% Methanol aqueous was used as extraction reagent, after preprocessing samples by ultrasonic oscillation, then injected into the chromatography Waters symmetry shield RP18 analytical column (150mm x 4.6mm, 5 microm), finally detected by an atomic fluorescence spectrometer. The calibration curves of analyses were linear over a range of concentrations (0.2-4mg L-1 and the correlation coefficients were higher than 0.9990. The limits of detection were 0.2 mg L-1. The method has been validated by linearity, precision and recovery. p-ASA and roxarsone in feed can be successfully and simultaneously determined using the developed method without a tedious pretreatment procedure.

Intragenic microdeletion of RUNX2 is a novel mechanism for cleidocranial dysplasia.

Cleidocranial dysplasia (CCD; MIM 119600) is a rare autosomal dominant disorder characterized by facial, dental, and skeletal malformations. To date, rearrangement and mutations involving RUNX2, which encodes a transcription factor required for osteoblast differentiation on 6p21, has been the only known molecular etiology for CCD. However, only 70% patients were found to have point mutations, 13% large/contiguous deletion but the rest of 17% remains unknown. We ascertained a family consisted of eight affected individuals with CCD phenotypes. Direct sequencing analysis revealed no mutations in the RUNX2. Real time quantitative PCR were performed which revealed an exon 2 to exon 6 intragenic deletion in RUNX2. Our patients not only demonstrated a unique gene change as a novel mechanism for CCD, but also highlight the importance of considering "deletion" and "duplication" in suspected familial cases before extensive effort of gene hunting be carried.

Ethyl 1-(6-chloro-3-pyridylmeth-yl)-5-methyl-1H-1,2,3-triazole-4-carboxyl-ate.

In the title compound, C(12)H(13)ClN(4)O(2), the triazole ring carries methyl and ethoxy-carbonyl groups, and is bound via a methyl-ene bridge to a chloro-pyridine unit. There is evidence for significant electron delocalization in the triazolyl system. Intra-molecular C-H⋯O and inter-molecular C-H⋯N hydrogen bonds stabilize the structure.

Ethyl 1-(6-chloro-3-pyridylmeth-yl)-5-ethoxy-methyl-eneamino-1H-1,2,3-triazole-4-carboxyl-ate.

In the title compound, C(14)H(16)ClN(5)O(3), there is evidence for significant electron delocalization in the triazolyl system. Intra-molecular C-H⋯O and inter-molecular C-H⋯O and C-H⋯N hydrogen bonds stabilize the structure.

Ethyl 1-[(2-chloro-1,3-thia-zol-5-yl)methyl]-5-methyl-1H-1,2,3-triazole-4-carboxylate.

In the title compound, C(10)H(11)ClN(4)O(2)S, the triazole ring carries methyl and ethoxy-carbonyl groups and is bound via a methyl-ene bridge to a chloro-thia-zole unit. There is also evidence for significant electron delocalization in the triazolyl system. Intra- and inter-molecular C-H⋯O hydrogen bonds together with strong π-π stacking inter-actions [centroid-centroid distance 3.620 (1) Å] stabilize the structure.

[Study on the presence of hepatitis B virus in first-trimester villi in pregnant women with hepatitis B surface antigen positive].

OBJECTIVE: To observe the presence of hepatitis B virus (HBV) in first-trimester villi cells from pregnant women carrying HBsAg. METHODS: Immunohistochemical streptavidin-biotin peroxidase complex (SABC) staining with monoclonal HBsAg, hepatitis B core antigen (HBcAg) and PCR, in situ hybridization were used for detection of HBV infection markers in villi. Positive villi ultramicrostructures were observed with transmission electron microscope. RESULTS: HBV was detected in 8 of 25 villi of HBsAg positive pregnant women, the positive rate was 32%. HBsAg was located in the decidual cell, trophoblastic cell and villous mesenchymal cell. HBV analog was detected in rough endoplasmic reticulum of trophoblastic cell. CONCLUSIONS: HBV may infect villous cells in first-trimester pregnancy. It would be impossible for HBV to transmit the desmosomes.