Affiliate stigma and caregiver burden in parents of children with epilepsy.

Objective: This study aimed to investigate the current status of affiliated stigma and caregiver burden among parents of children with epilepsy, analyze their correlation, and identify factors influencing affiliated stigma. Methods: A cross-sectional survey was conducted among 194 parents of children with epilepsy who met the inclusion and exclusion criteria in Shenzhen City, Guangdong Province, China. Data were collected through questionnaires, including a demographic information sheet, an affiliated stigma scale, and a caregiver burden scale. Results: The results revealed that parents of children with epilepsy experienced a moderate level of affiliated stigma, with an average score of 54.92 ± 10.44. Similarly, caregiver burden scores fell within the moderate range, with an average score of 44.14 ± 16.02. Factors influencing affiliated stigma scores included the frequency of epileptic seizures in children, the types of anti-epileptic medications taken by children, and the place of residence. The total caregiver burden score and scores in various dimensions (emotional, cognitive, and behavioral) of caregivers for epilepsy patients were positively correlated with the affiliated stigma score. Affiliated stigma was found to independently explain 21.3 % of the variation in caregiver burden. Conclusion: In the future, healthcare professionals should develop targeted interventions for children with epilepsy and their parents to reduce affiliated stigma, decrease caregiver burden, and enhance the caregiving capabilities of parents of children with epilepsy. These measures are essential to improve the overall well-being of both parents and children affected by epilepsy.

The comparative study revealed that the hTERT-CSF cell line was the most susceptible cell to the Lumpy skin disease virus infection among eleven cells.

Lumpy skin disease virus (LSDV) is a rapidly emerging pathogen in Asia, including China. Improving the propagation of LSDV is important for diagnostics and vaccine production. Our study identified and compared the LSDV susceptibility of eleven standard cells using western blot, indirect immune-fluorescence assay, quantitative PCR, and 50 % tissue culture infectious dose. Our finding revealed that the LSDV strain could infect five cell lines and show a cytopathic effect. Furthermore, the hTERT-CSF cell line had the highest level of virus in the five cell models, followed by BHK-21, MDBK, Vero, and hTERT-ST. Hence, hTERT-CSF could be used as a candidate cell line for basic and applied research, clinical application, and LSDV vaccine development, providing a vital reference in LSDV and other viruses.

Electronic, Magnetic, and Optical Properties of Metal Adsorbed g-ZnO Systems.

2D ZnO is one of the most attractive materials for potential applications in photocatalysis, gas and light detection, ultraviolet light-emitting diodes, resistive memory, and pressure-sensitive devices. The electronic structures, magnetic properties, and optical properties of M (Li, Na, Mg, Ca, or Ga) and TM (Cr, Co, Cu, Ag, or Au) adsorbed g-ZnO were investigated with density functional theory (DFT). It is found that the band structure, charge density difference, electron spin density, work function, and absorption spectrum of g-ZnO can be tuned by adsorbing M or TM atoms. More specifically, the specific charge transfer occurs between g-ZnO and adsorbed atom, indicating the formation of a covalent bond. The work functions of M adsorbed g-ZnO systems are obviously smaller than that of intrinsic g-ZnO, implying great potential in high-efficiency field emission devices. The Li, Na, Mg, Ca, Ga, Ag, or Au adsorbed g-ZnO systems, the Cr adsorbed g-ZnO system, and the Co or Cu adsorbed g-ZnO systems exhibit non-magnetic semiconductor proprieties, magnetic semiconductor proprieties, and magnetic metal proprieties, respectively. In addition, the magnetic moments of Cr, Co, or Cu adsorbed g-ZnO systems are 4 µ B, 3 µ B, or 1 µ B, respectively, which are mainly derived from adsorbed atoms, suggesting potential applications in nano-scale spintronics devices. Compared with the TM absorbed g-ZnO systems, the M adsorbed g-ZnO systems have more obvious absorption peaks for visible light, particularly for Mg or Ca adsorbed g-ZnO systems. Their absorption peaks appear in the near-infrared region, suggesting great potential in solar photocatalysis. Our work contributes to the design and fabrication of high-efficiency field emission devices, nano-scale spintronics devices, and visible-light responsive photocatalytic materials.

MiR-128-3p suppresses tumor proliferation and metastasis via targeting CDC6 in hepatocellular carcinoma cells.

BACKGROUND: MicroRNAs (miRNAs) are known to be involved in the pathogenesis of various cancers. The present study devotes efforts to discover the role of miR-128-3p in hepatocellular carcinoma (HCC). METHODS: MiR-128-3p and cell division cycle 6 (CDC6) expressions in HCC tissue (n = 50) and adjacent normal tissue (n = 50) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). MTT assay and flow cytometry were applied to measure the viability and cell cycle distribution of HuH7 and HCCLM3 cells, respectively. The potential binding sites of miR-128-3p on CDC6 were predicted with Targetscan 7.2 and confirmed by dual-luciferase reporter assay. Expression analysis of CDC6 and survival analysis in HCC were performed by GEPIA2. Wound healing and Transwell assays were used to detect HCC cell migration and invasion, respectively. Expressions of miR-128-3p and epithelial-mesenchymal transition (EMT)-related proteins (MMP2, MMP9, E-Cadherin, N-Cadherin and Vimentin) were quantified using qRT-PCR and western blot, respectively. RESULTS: MiR-128-3p mRNA expression was lower in HCC tissue than in adjacent normal tissues. HCC cell viability was suppressed and cell cycle was arrested in G0/S phase by miR-128-3p mimic. CDC6 was targeted by miR-128-3p and had higher expression in HCC tissue. The promotive effects of overexpressed CDC6 on HCC cell viability, migration and invasion were reversed by up-regulating miR-128-3p. And the effects of overexpressed CDC6 on inhibiting E-Cadherin expression yet promoting MMP2, MMP9, N-Cadherin and Vimentin expressions in HCC cells were reversed by up-regulating miR-128-3p. CONCLUSION: MiR-128-3p may suppress HCC cell proliferation and metastasis via targeting CDC6.

Perturbation of Specific Signaling Pathways Is Involved in Initiation of Mouse Liver Fibrosis.

BACKGROUND AND AIMS: To identify the regulatory role of protein phosphatase 2A (PP2A) in the development of liver disease, we generated a mouse model with hepatocyte-specific deletion of Ppp2r1a gene (encoding PP2A Aα subunit). APPROACH AND RESULTS: Homozygote (HO) mice and matched wild-type littermates were investigated at 3, 6, 9, 12, 15, and 18 months of age. Pathological examination showed that PP2A Aα deficiency in hepatocytes resulted in progressive liver fibrosis phenotype from 9 months of age. No hepatocyte death was observed in HO mice. However, perturbation of pathways including epidermal growth factor receptor 1 (EGFR1), amino acid metabolism, and translation factors as well as leptin and adiponectin led to pronounced hepatic fibrosis. In vitro studies demonstrated the involvement of specific B subunit complexes in the regulation of EGFR1 signaling pathway and cross talk between defected hepatocytes and stimulation of interstitial hyperplasia. It is noteworthy that HO mice failed to develop hepatocellular carcinoma for as long as 22 months of age. We further demonstrate that PP2A Aß-containing holoenzymes played a critical role in preventing hepatocyte apoptosis and antagonizing tumorigenesis through specific pathways on Aα loss. Furthermore, PP2A Aα and Aß were functionally distinct, and the Aß isoform failed to substitute for Aα in the development of inflammation and liver fibrosis. CONCLUSIONS: These observations identify pathways that contribute to the pathogenesis of liver fibrosis and provide putative therapeutic targets for its treatment.

Catalpol inhibits the proliferation, migration and metastasis of HCC cells by regulating miR­140­5p expression.

Hepatocellular carcinoma (HCC) is a frequent malignant tumor. Catalpol is a Chinese medicine extract with a number of pharmacologically active properties. The present study aimed to investigate the effects and mechanisms of catalpol in HCC. HCC cells were treated with catalpol in the presence or absence of microRNA (miR)­140­5p inhibitor, and assays to determine cell viability, proliferation, invasion and migration were performed. Reverse transcription­quantitative PCR and western blotting were performed to determine the mRNA and protein expression levels of miR­140­5p, vimentin, N­Cadherin and E­Cadherin. Moreover, cells were treated with catalpol in the absence or presence of transforming growth factor (TGF)­ß1, and the cell morphology was observed under a microscope. The results demonstrated that catalpol inhibited cell proliferation, invasion and migration, and decreased the expression levels of vimentin and N­cadherin, but increased the expression levels of E­cadherin and miR­140­5p. Catalpol inhibited morphological changes in epithelial­mesenchymal transformation (EMT) of cells induced by TGF­ß1. Following inhibition of miR­140­5p expression, the proliferation, invasion and migration of HCC cells were promoted, E­cadherin expression was decreased, and the levels of vimentin and N­cadherin were increased. The miR­140­5p inhibitor effectively reversed the inhibitory effect of catalpol on cell proliferation, invasion and migration. Thus, the results suggested that the antitumor potential of catalpol in HCC may be exerted by regulating the expression of miR­140­5p to inhibit proliferation, invasion, migration and EMT of HCC cells.

Boosting the Utilization and Electrochemical Performances of Polyaniline by Forming a Binder-Free Nanoscale Coaxially Coated Polyaniline/Carbon Nanotube/Carbon Fiber Paper Hierarchical 3D Microstructure Composite as a Supercapacitor Electrode.

Nanoscale polyaniline (PANI) is formed on a hierarchical 3D microstructure carbon nanotubes (CNTs)/carbon fiber paper (CFP) substrate via a one-step electrochemical polymerization method. The chemical and structural properties of the binder-free PANI/CNTs/CFP electrode are characterized by field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. The specific capacitance of PANI/CNTs/CFP tested in a symmetric two-electrode system reaches 731.6 mF·cm-2 (1354.7 F·g-1) at a current density of 1 mA·cm-2 (1.8 A·g-1). The symmetric supercapacitor device demonstrates excellent cycling performance up to 10,000 cycles with a capacitance retention of 81.4% at a current density of 1 mA·cm-2 (1.8 A·g-1). The results demonstrate that the binder-free CNTs/CFP composite is a strong backbone for depositing ultrathin PANI layers at a high mass loading. The hierarchical 3D microstructure PANI/CNTs/CFP provides enough space and transporting channels to form an efficient electrode-electrolyte interface for the supercapacitance reaction. The formed nanoscale PANI film coaxially coated on the sidewalls of CNTs enables efficient charge transfer and a shortened diffusion length. Hence, the utilization efficiency and electrochemical performances of PANI are significantly improved. The rational design strategy of a CNT-based binder-free hierarchical 3D microstructure can be used in preparing various advanced energy-storage electrodes for electrochemical energy-storage and conversion systems.

The Moderation Effect of Self-Enhancement on the Group-Reference Effect.

Previous studies have documented that people tend to respond faster and memorize better to the in-group traits. It may be particularly manifest for ethnic minorities, due to their salient ethnic identity. However, few studies have explored how the valence of traits modulates the in-group preference effect. The present study examined the impacts of ethnic identity salience and the valence of traits on the group-preference effect among 33 Han Chinese in a Tibetan-dominant area and 32 Tibetan participants in a Han-dominant area. Two weeks before the experiment, we measured the ethnic identity salience of participants in both groups. In the formal experiment, we used the group-reference effect (GRE) paradigm with three encoding tasks. The results showed that, regardless of whether ethnic identity was salient, both groups responded faster to positive traits than to negative traits when evaluating their own group, whereas there were no significant difference between the processing of positive traits and negative traits in the out-group evaluation and font judgment tasks. This suggested a pervasive processing advantage of the in-group positive characteristics. The results imply that self-enhancement motivation had a moderation effect on the GRE, as well as the ethnic identity salience may not be necessary for a GRE.

Benzene-induced mouse hematotoxicity is regulated by a protein phosphatase 2A complex that stimulates transcription of cytochrome P4502E1.

Chronic benzene exposure is associated with hematotoxicity and the development of aplastic anemia and leukemia. However, the signaling pathways underlying benzene-induced hematotoxicity remain to be defined. Here, we investigated the role of protein phosphatase 2A (PP2A) in the regulation of benzene-induced hematotoxicity in a murine model. Male mice with a hepatocyte-specific homozygous deletion of the Ppp2r1a gene (encoding PP2A Aα subunit) (HO) and matched wildtype (WT) mice were exposed to benzene via inhalation at doses of 1, 10, and 100 ppm for 28 days. Peripheral white blood cell counts and activation of bone marrow progenitors were attenuated in the HO mice, indicating that Ppp2r1a deletion protects against benzene-induced hematotoxicity. Moreover, elevation of urinary S-phenyl mercapturic acid, a benzene metabolite, was much greater in WT mice than in HO mice. Real-time exhalation analysis revealed more exhaled benzene but fewer benzene metabolites in HO mice than in WT mice, possibly because of the down-regulation of Cyp2e1, encoding cytochrome P4502E1, in hepatocytes of the HO mice. Loss-of-function screening disclosed that PP2A complexes containing the B56α subunit participate in regulating Cyp2e1 expression. Notably, PP2A-B56α suppression in HepG2 cells resulted in persistent ß-catenin phosphorylation at Ser33-Ser37-Thr41 in response to CYP2E1 agonists. In parallel, nuclear translocation of ß-catenin was inhibited, concomitant with a remarkable decrease of Cyp2e1 expression. These findings support the notion that a regulatory cascade comprising PP2A-B56α, ß-catenin, and Cyp2e1 is involved in benzene-induced hematotoxicity, providing critical insight into the role of PP2A in responses to the environmental chemicals.

Sphingosine kinase 1 overexpression is associated with poor prognosis and oxaliplatin resistance in hepatocellular carcinoma.

Sphingosine kinase 1 (SphK1) is a tumor-associated protein overexpressed in numerous types of cancer and is involved in the regulation of resistance to multiple chemotherapeutic agents. However, the role of SphK1 in the resistance of hepatocellular carcinoma (HCC) to oxaliplatin remains unclear. In the present study, the transcriptional levels of SphK1 were analyzed in 21 patients with HCC and the SphK1 expression levels were identified to be significantly upregulated in HCC tissue compared with that in adjacent normal tissue samples (P<0.001). High SphK1 expression correlated with shorter overall survival times in patients with HCC (P<0.05). Furthermore, SphK1 expression levels and activity were analyzed in a series of HCC cell lines and they were both demonstrated to be associated with resistance to oxaliplatin. Conversely, the knockdown of SphK1 protein expression resulted in decreased oxaliplatin resistance in SK-Hep1 and HCCLM3 cell lines. In addition, the results of the current study demonstrated that the downregulation of SphK1 decreased the levels of phosphorylated AKT serine/threonine kinase (Akt) and glycogen synthase kinase-3ß (GSK3ß), suggesting that SphK1 promotes oxaliplatin resistance of HCC cells via modulation of the Akt/GSK3ß signaling pathway. To the best of our knowledge, the present study is the first to report that SphK1 is associated with poor prognosis and oxaliplatin resistance in HCC. Thus, the findings of the current study have provided a direction for the identification of novel therapeutic targets for the treatment of HCC.

Microwave synthesis of three-dimensional nickel cobalt sulfide nanosheets grown on nickel foam for high-performance asymmetric supercapacitors.

A facile and cost-effective microwave method is developed to prepare ternary nickel cobalt sulfide (NiCo2S4) interconnected nanosheet arrays on nickel foam (NF). When acting as an electrochemical supercapacitor electrode material, the as-prepared NiCo2S4/NF shows a high specific capacitance of 1502 F g-1 at a current density of 1 A g-1, and outstanding cycling stability of 91% capacitance retention after 8000 cycles. In addition, a asymmetric supercapacitor (ASC) is composed of NiCo2S4/NF as positive electrode and activated carbon as negative electrode, which exhibits a high energy density of 34.7 W h kg-1 at a power density of 750 W kg-1 and long-term cyclic stability (83.7% capacity retention after 8000 cycles). Even at a high power density of 15 kW kg-1, it still remains an energy density of 17.9 W h kg-1, which is able to light up a light-emitting diode. These findings provide a new and facile approach to fabricate high-performance electrode for supercapacitors.

Enhanced H3K4me3 modifications are involved in the transactivation of DNA damage responsive genes in workers exposed to low-level benzene.

In this study, we explore whether altered global histone modifications respond to low-level benzene exposure as well as their association with the hematotoxicity. We recruited 147 low-level benzene-exposed workers and 122 control workers from a petrochemical factory in Maoming City, Guangdong Province, China. The internal exposure marker level, urinary S-phenylmercapturic acid (SPMA), in benzene-exposed workers was 1.81-fold higher than that of the controls (P < 0.001). ELISA method was established to examine the specific histone modifications in human peripheral blood lymphocytes (PBLCs) of workers. A decrease in the counts of white blood cells (WBC), neutrophils, lymphocytes, and monocytes appeared in the benzene-exposed group (all P < 0.05) compared to the control group. Global trimethylated histone 3 lysine 4 (H3K4me3) modification was enhanced in the benzene-exposed group (P < 0.05) and was positively associated with the concentration of urinary SPMA (ß = 0.103, P = 0.045) and the extent of DNA damage (% Tail DNA: ß = 0.181, P = 0.022), but was negatively associated with the leukocyte count (WBC: ß = -0.038, P = 0.023). The in vitro study revealed that H3K4me3 mark was enriched in the promoters of several DNA damage responsive (DDR) genes including CRY1, ERCC2, and TP53 in primary human lymphocytes treated with hydroquinone. Particularly, H3K4me3 modification was positively correlated with the expression of CRY1 in the PBLCs of benzene-exposed workers. These observations indicate that H3K4me3 modification might mediate the transcriptional regulation of DDR genes in response to low-dose benzene exposure.

Red warning for air pollution in China: Exploring residents' perceptions of the first two red warnings in Beijing.

Air pollution early warnings have been issued in China to mitigate the effects of high pollution days. Public perceptions and views about early warning signals can affect individual behaviors and play a major role in the public's response to air pollution risks. This study examined public attitudes and responses to the first two red warnings for air pollution in Beijing in 2015. An online survey was sent out, and 664 respondents (response rate = 90%) provided their perspectives on the red warnings. Descriptive statistics, sign tests and binary logit models were used to analyze the data. More than half of the respondents reported that their life and work were affected by the red warning in December 2015. In contrast to their perceptions about the second red warning period, the public thought that the first red warning should have been issued earlier and that the number of consecutive days of warnings should have been reduced. The respondents also recommended that instead of reducing the number of red warnings, the red warning emergency measures should be adjusted. Specifically, the public preferred the installation of air purifiers in schools rather than closing schools and strengthening road flushing and dust pollution controls over restrictions on driving. Data analyses were conducted to examine the affected groups and different groups' perceptions of the necessity of implementing emergency measures. The results indicated that men and more educated respondents were more likely to be affected by driving limitations, and men were less supportive of these limitations. The age and education of respondents were significantly negatively associated with the opinion that schools should be closed, whereas wealthier respondents were more supportive of school closings. The finding of a negative attitude among the public toward the first two red warnings may be used to help local governments modify protective measures and pollution mitigation initiatives to increase acceptance.

Hydrothermal synthesis of flower-like molybdenum disulfide microspheres and their application in electrochemical supercapacitors.

Three-dimensional flower-like molybdenum disulfide microspheres composed of nanosheets were prepared by a hydrothermal method using ammonium molybdate as the molybdenum source and thiourea as the sulfur source. Structural and morphological characterizations were performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy and X-ray photoelectron spectroscopy (XPS). The electrochemical properties of MoS2 electrode were studied by performing cyclic voltammetry (CV), galvanostatic charge-discharge analysis and electrochemical impedance spectroscopy (EIS). When used as an electrode material for supercapacitor, the hybrid MoS2 showed a high specific capacity of 518.7 F g-1 at a current density of 1 A g-1 and 275 F g-1 at a high discharge current density of 10 A g-1. In addition, a symmetric supercapacitor composed of MoS2 as positive and negative electrodes was prepared, which exhibited a high energy density of 12.46 W h kg-1 at a power density of 70 W kg-1 and still maintains an impressive energy density of 6.42 W h kg-1 at a large power density of 7000 W kg-1. The outstanding performance of the MoS2 electrode material indicates its great potential for applications in high-performance energy storage systems.

TRIM36 hypermethylation is involved in polycyclic aromatic hydrocarbons-induced cell transformation.

Long term exposure to polycyclic aromatic hydrocarbons (PAHs) is associated with the increasing risk of lung cancer. To identify differentially hypermethylated genes associated with PAHs-induced carcinogenicity, we performed genome-wide DNA methylation analysis in 20 µM benzo(a)pyrene (BaP)-transformed human bronchial epithelial (HBE) cells at different stages of cell transformation. Several methylated genes (CNGA4, FLT1, GAREM1, SFMBT2, TRIM36) were differentially hypermethylated and their mRNA was suppressed in cells at both pre-transformed and transformed stages. Similar results were observed in HBE cells transformed by 20 µg/mL coke oven emissions (COEs) mixture collected from a coking manufacturing facility. In particular, hypermethylation of TRIM36 and suppression of TRIM36 expression were gradually enhanced over the time of COEs treatment. We developed bisulfite pyrosequencing assay and assessed TRIM36 methylation quantitatively. We found that hypermethylation of TRIM36 and reduced gene expression was prevalent in several types of human cancers. TRIM36 hypermethylation appeared in 90.0% (23/30) of Non-Small Cell Lung Cancer (NSCLCs) tissues compared to their paired adjacent tissues with an average increase of 1.32 fold. Furthermore, an increased methylation rate (5.90% v.s 7.38%) and reduced levels of TRIM36 mRNA were found in peripheral lymphocytes (PBLCs) of 151 COEs-exposed workers. In all subjects, TRIM36 hypermethylation was positively correlated with the level of urinary 1-hydroxypyrene (P < 0.001), an internal exposure marker of PAHs, and the DNA damage (P = 0.013). These findings suggest that aberrant hypermethylation of TRIM36 might be involved in the acquisition of malignant phenotype and could be served as a biomarker for risk assessment of PAHs exposure.

Effects of plant species richness on 13C assimilate partitioning in artificial grasslands of different established ages.

Artificial grasslands play a role in carbon storage on the Qinghai-Tibetan Plateau. The artificial grasslands exhibit decreased proportions of graminate and increased species richness with age. However, the effect of the graminate proportions and species richness on ecosystem C stocks in artificial grasslands have not been elucidated. We conducted an in situ13C pulse-labeling experiment in August 2012 using artificial grasslands that had been established for two years (2Y), five years (5Y), and twelve years (12Y). Each region was plowed fallow from severely degraded alpine meadow in the Qinghai-Tibetan Plateau. The 12Y grassland had moderate proportions of graminate and the highest species richness. This region showed more recovered 13C in soil and a longer mean residence time, which suggests species richness controls the ecosystem C stock. The loss rate of leaf-assimilated C of the graminate-dominant plant species Elymus nutans in artificial grasslands of different ages was lowest in the 12Y grassland, which also had the highest species richness. Thus the lower loss rate of leaf-assimilated C can be partially responsible for the larger ecosystem carbon stocks in the 12Y grassland. This finding is a novel mechanism for the effects of species richness on the increase in ecosystem functioning.

Persistent phosphorylation at specific H3 serine residues involved in chemical carcinogen-induced cell transformation.

Identification of aberrant histone H3 phosphorylation during chemical carcinogenesis will lead to a better understanding of the substantial roles of histone modifications in cancer development. To explore whether aberrant H3 phosphorylation contributes to chemical carcinogenesis, we examined the dynamic changes of H3 phosphorylation at various residues in chemical carcinogen-induced transformed human cells and human cancers. We found that histone H3 phosphorylation at Ser10 (p-H3S10) and Ser28 (p-H3S28) was upregulated by 1.5-4.8 folds and 2.1-4.3 folds, respectively in aflatoxin B1 -transformed hepatocytes L02 cells (L02RT-AFB1 ), benzo(a)pyrene-transformed HBE cells (HBERT-BaP), and coke oven emissions-transformed HBE cells (HBERT-COE). The ectopic expression of histone H3 mutant (H3S10A or H3S28A) in L02 cells led to the suppression of an anchorage-independent cell growth as well as tumor formation in immunodeficient mice. In addition, an enhanced p-H3S10 was found in 70.6% (24/34) of hepatocellular carcinoma (HCC), and 70.0% (21/30) of primary lung cancer, respectively. Notably, we found that expression of H3 carrying a mutant H3S10A or H3S28A conferred to cells the ability to maintain a denser chromatin and resistance to induction of DNA damage and carcinogen-induced cell transformation. Particularly, we showed that introduction of a mutant H3S10A abolished the bindings of p-H3S10 to the promoter of DNA repair genes, PARP1 and MLH1 upon AFB1 treatment. Furthermore, we revealed that PP2A was responsible for dephosphorylation of p-H3S10. Taken together, these results reveal a key role of persistent H3S10 or H3S28 phosphorylation in chemical carcinogenesis through regulating gene transcription of DNA damage response (DDR) genes.

MGMT hypomethylation is associated with DNA damage in workers exposed to low-dose benzene.

OBJECTIVE: This study aims to assess the effects of low-dose benzene on DNA damage and O6-methylguanine-DNA methyltransferase (MGMT) methylation in occupational workers. MATERIALS AND METHODS: We recruited 96 nonsmoking male petrochemical industry workers exposed to low-dose benzene and 100 matched control workers. Urinary S-phenylmercapturic acid (SPMA) and S-benzylmercapturic acid (SBMA) were measured for indicating internal exposure of benzene and toluene. The degree of DNA damage was determined by the Comet assay. The levels of MGMT methylation were detected quantitatively by bisulphite-PCR pyrosequencing assay. RESULTS: The benzene-exposed workers had significantly higher levels of urinary SPMA, degree of DNA damage but decreased MGMT methylation than the controls (all p < 0.05). In contrast, the level of urinary SBMA does not differ between benzene-exposed workers and the controls. In all participants, MGMT methylation was negatively associated with the urinary SPMA and the degree of DNA damage, indicating that epigenetic regulation might be involved in response to low-dose benzene exposure-induced genetic damage. DISCUSSION AND CONCLUSION: MGMT methylation could be a potent biomarker associated with low-dose benzene exposure and benzene-induced DNA damage.

Selective demineralisation of dentine extrafibrillar minerals-A potential method to eliminate water-wet bonding in the etch-and-rinse technique.

OBJECTIVE: The present study tested the central hypothesis that selective demineralisation of dentine extrafibrillar minerals by lowering the phosphoric acid concentration improves the quality of the resin-dentine interface. METHODS: Dentine surfaces were etched with different concentrations of phosphoric acid (1, 5, 10, 20, 30 or 40wt%). Scanning electron microscopy was used to observe the micromorphology of the etched dentine surfaces. Energy dispersive X-ray analysis was performed to determine the residual Ca-content of the demineralised dentine matrix. Atomic force microscopy-based nanoindentation was used to analyse the nanomechanical properties of the treated dentine surfaces. The influence of H3PO4 concentration on resin-dentine bond strength was evaluated by microtensile bond strength testing. One-way ANOVA was used to compare the residual Ca-content ratio, reduced elastic modulus (Er) of the treated dentine surfaces and microtensile bond strength among groups. RESULTS: Collagen fibrils appeared to be wider in diameter after etching with 5% and 10% H3PO4. The partially-demineralized collagen scaffold retained part of its rigidity to maintain an uncollapsed three-dimensional structure. Etching with 1% H3PO4 resulted in the highest residual Ca-content ratio and Er of demineralised dentine matrix, followed by 5% H3PO4. Those values were all significantly higher than values derived from the other groups. Etching with 30% H3PO4 resulted in the lowest Ca-content ratio and Er. Using 5% H3PO4 as etchant resulted in the highest resin-dentine bond strength. CONCLUSIONS: Selective demineralisation of the dentine matrix may be achieved by lowering the H3PO4 concentration to 5wt%, to achieve better bonding performance. CLINICAL RELEVANCE: By retaining intrafibrillar minerals, more through air-drying of the partially demineralised collagen matrix may be accomplished without the need to worry about collapsing a mineral-free collagen matrix during air-drying. This may result in the elimination of water-wet bonding during the application of etch-and-rinse adhesives.