Introducing defects and in situ topotactic transformation of the electrocatalysts generating heterostructures of mixed‐metal oxides(hydroxides) that are highly active for oxygen evolution reaction (OER) in tandem with metals of low hydrogen adsorption barrier for efficient hydrogen evolution reaction (HER) is urgently demanded for boosting the sluggish OER and HER kinetics in alkaline media. Ascertaining that, metal–organic‐framework‐derived freestanding, defect‐rich, and in situ oxidized Fe–Co–O/Co metal@N‐doped carbon (Co@NC) mesoporous nanosheet (mNS) heterostructure on Ni foam (Fe–Co–O/Co@NC‐mNS/NF) is developed from the in situ oxidation of micropillar‐like heterostructured Fe–Co–O/Co@NC/NF precatalyst. The in situ oxidized Fe–Co–O/Co@NC‐mNS/NF exhibits excellent bifunctional properties by demanding only low overpotentials of 257 and 112 mV, respectively, for OER and HER at the current density of 10 mA cm−2, with long‐term durability, attributed to the existence of oxygen vacancies, higher specific surface area, increased electrochemical active surface area, and in situ generated new metal (oxyhydr)oxide phases. Further, Fe–Co–O/Co@NC‐mNS/NF (+/−) electrolyzer requires only a low cell potential of 1.58 V to derive a current density of 10 mA cm−2. Thus, the present work opens a new window for boosting the overall alkaline water splitting.

Global hypomethylation, gene-specific methylation, and genome instability are common events in tumorigenesis. To date, few studies have examined the aberrant DNA methylation patterns in coke oven workers, who are highly at risk of lung cancer by occupational exposure to polycyclic aromatic hydrocarbons (PAHs). We recruited 82 PAH-exposed workers and 62 unexposed controls, assessed exposure levels by urinary 1-hydroxypyrene, and measured genetic damages by comet assay, bleomycin sensitivity, and micronucleus assay. The PAHs in coke oven emissions (COE) were estimated based on toxic equivalency factors. We used bisulfite-PCR pyrosequencing to quantitate DNA methylation in long interspersed nuclear element-1 (LINE-1) and O(6)-methylguanine-DNA methyltransferase (MGMT). Further, the methylation alteration was also investigated in COE-treated human bronchial epithelial (16HBE) cells. We found there are higher levels of PAHs in COE. Among PAH-exposed workers, LINE-1 and MGMT methylation levels (with CpG site specificity) were significantly lowered. LINE-1, MGMT, and its hot CpG site-specific methylation were negatively correlated with urinary 1-hydroxypyrene levels (r = -0.329, p < 0.001; r = -0.164, p = 0.049 and r = -0.176, p = 0.034, respectively). In addition, LINE-1 methylation was inversely associated with comet tail moment and micronucleus frequency, and a significant increase of micronucleus in low MGMT methylation group. In vitro study revealed that treatment of COE in 16HBE cells resulted in higher production of BPDE-DNA adducts, LINE-1 hypomethylation, hypomethylation, and suppression of MGMT expression. These findings suggest hypomethylation of LINE-1 and MGMT promoter could be used as markers for PAHs exposure and merit further investigation.

In this study, the effect of ionizing radiation on 8-hydroxy-2′-deoxyguanosine (8-OHdG) in human peripheral blood was investigated. Blood samples were collected from 230 radiation workers and 8 patients who underwent radiotherapy for population study. Blood samples from 2 healthy individuals were irradiated with different X-ray doses for in vitro experiment, and levels of 8-OHdG in serum and cell culture supernatants were assessed by enzyme-linked immunosorbent assay. Observations demonstrated the positive relationships between serum 8-OHdG level and radiation dose and working period were observed, and serum 8-OHdG levels were higher among interventional radiation workers than among other hospital radiation workers. In addition, 8-OHdG yields in supernatants increased, peaked at 3 Gy of radiation dose, and then decreased with further increases in radiation; the dose–response curve obtained fitted a polynomial function. By contrast, a similar trend was not found in radiotherapy patients. The present study suggests that 8-OHdG may be a useful biomarker reflecting oxidative damage among workers occupationally exposed to low-dose radiation.

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Skin tissue engineering is a possible solution for the treatment of extensive skin defect. The ultimate goal of skin tissue engineering is to restore the complete functions of native skin, but until now the structures and functions of skins are only partially restored. By negative immunoselection (CD45 and glycophorin A), we isolated and cultivated adult human bone marrow stem cells (hBMSCs) that are of multilineage differentiation potential. In this study, we first demonstrated that by using gelatin/thermo-sensitive poly N-isopropylacrylamide (pNIPAAm) and the immunocompromised mice model, the hBMSCs possess the differentiation potential of epidermis and the capability of healing skin wounds. The in vitro observations and the results of the scanning electron microscope showed that the hBMSCs can attach and proliferate in the gelatin/thermo-sensitive pNIPAAm. To further monitor the in vivo growth effect of the hBMSCs in the skin-defected nude mice, the green fluorescence protein (GFP) gene was transduced into the hBMSCs by the murine stem cell viral vector. The results showed that the rates of cell growth and wound recovery in the hBMSC-treated group were significantly higher than those in the control group, which was only treated with the gelatin/pNIPAAm (p < 0.01). More importantly, the re-epithelialization markers of human pan-cytokeratin and E-cadherin were significantly increased on day 7, day 14, and day 21 after the hBMSC-scaffold with the pNIPAAM in the mice with skin defects (p < 0.05). Moreover, the stem cell markers of human CD13 and CD105 were gradually decreased during the period of wound healing. In sum, this novel method provides a transferring system for cell therapies and maintains its temperature-sensitive property of easy-peeling by lower-temperature treatment. In addition, the in vitro and in vivo GFP imaging systems provide a new imaging modality for understanding the differentiation process and the effective expression of stem cells in wound healing.

Enhancement of IPC differentiation from EB-dissociated ES cells can be revealed by simply using pax4 expressing plasmid delivery. Not only more IPCs but also pancreatic differentiation-related genes can be detected by SQ-PCR. Expression of relative genes, such as foxa 2, mixl 1, pdx-1, insulin 1 and somatostatin after nucleofection, suggests that pax4 accelerates the whole differentiation progress. The higher insulin production with glucose dependent modulation suggests that pax4 expression can drive more mature IPCs. Although further determination of the entire mechanism is required, the potential of pax-4-nucleofected cells in medical treatment is promising.

DNA repair is an essential mechanism for cells to maintain their genomic integrity under endogenous or exogenous assault. Reduced DNA repair capacity (DRC) is associated with increased risk for several environmentally related cancers. The micronucleus in peripheral lymphocytes has been validated as a biomarker of chromosomal damage, increasing cancer risk in human populations. We hypothesized that suboptimal DRC is associated with the increase in chromosomal damage among 94 coke-oven workers and 64 noncoke-oven controls. DRC was evaluated in isolated lymphocytes by comet assay. Chromosomal damage in peripheral lymphocytes was detected by cytokinesis-block micronucleus assay. Four common coding single nucleotide polymorphisms in the XRCC1 gene were genotyped. Coke-oven workers have significantly increased urinary 1-hydroxypyrene (9.0; 6.8-11.7 Mg/L versus 1.5, 1.3-1.7 Mg/L; P < 0.01) and micronucleus frequency (7.4% F 4.3% versus 3.0% F 3.0%; P < 0.01), and decreased DRC (55.9% F 16.4% versus 63.6% F 18.5%; P < 0.01) compared with controls. Significant correlations between DRC and micronucleus frequency were found in coke-oven workers (r = À0.32; P < 0.01; n = 94) and all study subjects (r = À0.32; P < 0.001; n = 158) but not in controls (r = À0.21; P = 0.11; n = 64). Variants of the Arg399Gln polymorphism were associated with a decreased DRC in both coke-oven workers (51.6% F 16.1% versus 60.6% F 15.7%; P < 0.01) and controls (59.1% F 18.5% versus 68.4% F 17.5%; P = 0.04). The complicated interrelationship of these multiple biomarkers was also identified by path analysis. These findings should facilitate developing a biomarkerbased risk assessment model for lung cancer in this occupational population. (Cancer Epidemiol Biomarkers Prev 2009;18(3):987 -93)