Biography:

In the past Zhigang Wang has collaborated on articles with Xiaobing Dou and Baiying Xu. One of their most recent publications is A spin-valve memory cell☆. Which was published in journal Journal of Magnetism and Magnetic Materials.

More information about Zhigang Wang research including statistics on their citations can be found on their Copernicus Academic profile page.

Zhigang Wang's Articles: (77)

A spin-valve memory cell☆

AbstractWe designed a binary memory and a quarternary memory, respectively. Both of these modes used spin-valve multilayer for not only data storing but also data sensing. The feasibility has been proved by experiments.

Research paperA yeast whole cell extract supports nucleotide excision repair and RNA polymerase II transcription in vitro

AbstractNucleotide excision repair (NER) and RNA polymerase II transcription are cellular processes that require the transcription/NER factor TFIIH. We have developed a whole cell extract from the yeast Saccharomyces cerevisiae that simultaneously supports both NER and RNA polymerase II transcription of independent substrates. NER activity in the yeast whole cell extract was readily detected in the absence of further supplementation but was stimulated in the presence of overexpressed Rad2 protein. The repair of N-acetyl-2-aminofluorene (AAF)-damaged DNA was dependent on RAD genes required for NER and deficient repair in rad mutant extracts was complemented by mixing different mutant extracts or by purified Rad proteins. Both the NER and transcription activities were stimulated by 5% polyethylene glycol in the whole cell extracts. Transcription activity from the template pCYC1G− was not affected by the presence of uracil-containing or AAF-damaged pUC18 DNA, which was expected to result in base excision repair (BER) and NER, respectively. An in vitro condition was defined that supported simultaneous NER and transcription independently in different substrates in the yeast whole cell extracts.

Regular articleGastrointestinal, hepatobiliary, and pancreatic pathologyInhibition of NF-κB Activation by 4-Hydroxynonenal Contributes to Liver Injury in a Mouse Model of Alcoholic Liver Disease

Long-term alcohol exposure sensitizes hepatocytes to tumor necrosis factor-α (TNF) cytotoxicity. 4-Hydroxynonenal (4-HNE) is one of the most abundant and reactive lipid peroxides. Increased hepatic 4-HNE contents present in both human alcoholics and alcohol-fed animals. In the present study, we investigated the effects of intracellular 4-HNE accumulation on TNF-induced hepatotoxicity and its potential implication in the pathogenesis of alcoholic liver disease. Male C57BL/6 mice were fed an ethanol-containing or a control diet for 5 weeks. Long-term alcohol exposure increased hepatic 4-HNE and TNF levels. Cell culture studies revealed that 4-HNE, at nontoxic concentrations, sensitized hepatocytes to TNF killing, which was associated with suppressed NF-κB transactivity. Further investigation demonstrated that 4-HNE prevented TNF-induced inhibitor of κBα phosphorylation without affecting upstream IκB kinase activity. An immunoprecipitation assay revealed that increased 4-HNE content was associated with increased formation of 4-HNE–inhibitor of κBα adduction in both 4-HNE–treated hepatocytes and in the livers of alcohol-fed mice. Prevention of intracellular 4-HNE accumulation by bezafibrate, a peroxisome proliferator-activated receptor-α agonist, protected hepatocytes from TNF killing via NF-κB activation. Supplementation of N-acetylcysteine, a glutathione precursor, conferred a protective effect on alcohol-induced liver injury in mice, was associated with decreased hepatic 4-HNE formation, and improved hepatic NF-κB activity. In conclusion, increased 4-HNE accumulation represents a potent and clinically relevant sensitizer to TNF-induced hepatotoxicity. These data support the notion that removal of intracellular 4-HNE can serve as a potential therapeutic option for alcoholic liver disease.

Quantitative analysis of RASSF1A promoter methylation in hepatocellular carcinoma and its prognostic implications

Highlights•RASSF1A is one of the tumor suppressor genes that is frequently inactivated by a methylation-based mechanism.•Aberrant methylation of RASSF1A is an accumulated progress in the development of HCC.•Hypermethylation of the RASSF1A promoter in HCC may not be a useful biomarker for the prognosis of HCC.

A meta-analysis of the relationship between lymphatic microvessel density and clinicopathological parameters in breast cancer

AbstractBackgroundBreast cancer is a common malignant neoplasm that is a leading cause of cancer death in women despite recent advances in treatment and research. The role of lymphangiogenesis in breast cancer development remains a source of controversy in current research.ObjectiveThe relationship between lymphatic microvessel density (LMVD) and the clinicopathological parameters of breast cancer can be effectively examined by meta-analysis of recent studies.MethodsA total of 10 relevant studies consisting of 1,044 total patients were examined by electronic searches of PubMed and Embase databases. Weighted mean difference (WMD) and 95% confidence intervals (CI) were estimated and pooled according to standard methods. LMVD data was pooled by tumor size, lymphatic node metastases, and tumor hormone receptor status of estrogen receptors (ER) and progesterone receptors (PR).ResultsA remarkable correlation between LMVD and lymph node metastases was observed in pooled analyses using a random-effects model (WMD: 2.72; 95%CI: 2.27, 3.16; P = 0.000). LMVD and tumor size showed a pooled WMD value of 0.00 (95%CI: -0.49, 0.50; P = 0.009), indicating no significant correlation between LMVD and tumor size. LMVD and either ER or PR status showed pooled WMD values of 0.24 (95%CI: -0.30, 0.79; P = 0.004) and -0.12 (95%CI: -0.81, 0.56, P = 0.301), respectively, also indicating no significant correlation between LMVD and ER or PR status.ConclusionA close relationship was observed between LMVD and lymph node metastases, though no correlation between LMVD and other important clinicopathological parameters was apparent. The current meta-analysis suggests that LMVD may be associated with increased metastatic activity in breast cancer, though the full role of lymphangiogenesis in breast cancer remains uncertain.

Fabrication of superhydrophobic surfaces with non-aligned alkyl-modified multi-wall carbon nanotubes

AbstractFilms of superhydrophobic multi-wall carbon nanotubes (MWCNTs) have been obtained by using alkyl-modified MWCNTs (MWCNT(COOC18H37)n) and a simple and effective preparation method. The films show both a high contact angle and a small sliding angle for water droplets. A particular characteristic is that on the superhydrophobic surface the alkyl-modified MWCNTs are not intentionally aligned, thus avoiding the preparation techniques using aligned carbon nanotubes to produce the same effect.

Transformation mechanism of a H2 molecule from physisorption to chemisorption in pristine and B-doped C20 fullerenes

AbstractUsing different density function methods, we examined the transformation processes from the physisorption state (state P) to the chemisorption state (state C) of a H2 molecule in a pristine fullerene C20 and a B-doped fullerene C19B system, models of hydrogen-storage solid materials. We explored the precise potential energy surfaces (PES) for the transformation process by fully optimizing all the stationary points including the stable points and the transition states without any restriction. Our results demonstrate that both the two transformation processes could undergo transition states. We anticipate that the results obtained in the present Letter are helpful to understand the adsorption mechanism of the H2 molecule in solid materials.

Research paperTheoretical study on electronic and vibrational properties of hydrogen bonds in glycine-water clusters

Highlights•Successful evidences of the covalent-like characteristics of H-bonds.•H-bond retains two effects on nuclear motions in water.•The redshifts of stretching modes indicate a strengthening of H-bonds.

Research paperAltered superatomic properties of [email protected]28 by the electron rearrangement via adatom defects

Highlights•The adatom changes the origin of 32-electron principle.•Covalent interaction plays a major role between the adatom and [email protected]28.•The thermal movement path of the carbon adatom is a two-step process.

Exome sequencing reveals a novel PTHLH mutation in a Chinese pedigree with brachydactyly type E and short stature

Highlights•We identified a novel PTHLH gene mutation in a pedigree with brachydactyly Type E and short stature by exome sequencing.•SignalP 4.1 Server analysis suggested that the p.L15R mutation can change the signal peptide cleavage site.•The functional analysis indicated that the PTHLHL15R led to the signal sequences not being cleaved off.

Effect of Agkistroden blomhoffi (mamushi) on the proliferation of human fibroblasts

AbstractObjectives: The purpose of this study is to investigate the effect of Agkistroden blomhoffi (mamushi) aqueous extract on human patellar tendon cells in vitro, to pharmacologically explain the natural medicine's healing effect on tendon, bone and muscle injuries.Design and methods: Human patellar tendon fibroblasts (HPTF) were incubated in media containing different concentrations of mamushi aqueous extract. Cell proliferation was studied by microscopic observations and total protein, actin, collagen I, and cyclooxygenase-2 (Cox 2) expressions.Results: Mamushi aqueous extract enhanced HPTF proliferation when its concentration was lower than 333 μg/ml. Cells cultured in manushi-containing medium showed developed intercellular structure and increased protein production. However, mamushi extract higher than 500 μg/ml oppressed cell growth. At 667 μg/ml, mamushi induced Cox 2 production, a sign of cytotoxicity.Conclusion: A. blomhoffi aqueous extract was found to directly stimulate the proliferation and protein production, particularly collagen I synthesis, of HPTF in a dose-dependent manner.

Efficient and stable nanoporous functional composited electrocatalyst derived from Zn/Co-bimetallic zeolitic imidazolate frameworks for oxygen reduction reaction in alkaline media

Highlights•Doping CNTs and the synergetic effect enhanced the poor conductivity of conventional MOFs and the blocked transfer of active substances in MOFs crystals.•Optimal catalyst [email protected] coexists exposed Co-Nx active sites and abundant N atomic species.•The ORR mainly favors a dominant four-electron transfer pathway.•[email protected] delivers remarkable durability and electrocatalytic activity in alkaline solution.

Studies on blends of LLDPE and ethylene-methacrylic acid random copolymer

AbstractBlends of linear low-density polyethylene (LLDPE) and poly(ethylene-co-methacrylic acid) (EMA) random copolymer were studied by differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and excimer fluorescence. In binary blends, crystallization of EMA was studied, and no modification of crystal structure was detected. In excimer fluorescence measurements, emission intensities of blends of EMA and naphthalene-labeled LLDPE were measured. The ratio of the excimer emission intensity (ID) to the emission intensity of the isolated “monomer” (IM) decreases upon addition of EMA, indicating that PE segments of EMA interpenetrate into the amorphous phase of LLDPE.

An improved preparation of α-fluorinated propargylphosphonates and the solid phase synthesis of α-hydroxy-γ-TIPS propargylphosphonate ester

AbstractDiethyl-3-triisopropylsilyl-1-propynephosphonate was fluorinated using NFSI to give the corresponding monofluoroderivative in good yield. The synthesis of diethyl-1,1-difluoro-3-triisopropylsilylpropynephosphonate was efficiently achieved following Burton’s methodology using CuCl/Cd to promote the coupling reaction of diethyl bromodifluoromethylphosphonate with the corresponding alkynyl iodide. Although the solid phase synthesis of α-hydroxy-γ-TIPS propargylphosphonate ester was carried out successfully, its fluorination — using DAST — failed.

P(MeNMCH2CH2)3N: an effective catalyst for trimethylsilycyanation of aldehydes and ketones

AbstractThe title non-ionic phosphazane base promotes the trimethylsilycyanation of aryl and alkyl aldehydes and ketones in moderate to high yields at room temperature. 29Si-NMR spectral evidence for the intermediacy of a phosphazane phosphorus–silicon adduct is presented.

Synthesis and characterization of Cr-MSU-1 and its catalytic application for oxidation of styrene

AbstractChromium-containing mesoporous silica material Cr-MSU-1 was synthesized using lauryl alcohol–polyoxyethylene (23) ether as templating agent under the neutral pH condition by two-step method. The sample was characterized by XRD, TEM, FT-IR, UV–Vis, ESR, ICP-AES and N2 adsorption. Its catalytic performance for oxidation of styrene was studied. Effects of the solvent used, the styrene/H2O2 mole ratio and the reaction temperature and time on the oxidation of styrene over the Cr-MSU-1 catalyst were examined. The results indicate that Cr ions have been successfully incorporated into the framework of MSU-1 and the Cr-MSU-1 material has a uniform worm-like holes mesoporous structure. After Cr-MSU-1 is calcined, most of Cr3+ is oxidized to Cr5+ and Cr6+ in tetrahedral coordination and no extra-framework Cr2O3 is formed. The Cr-MSU-1 catalyst is highly active for the selective oxidation of styrene and the main reaction products over Cr-MSU-1 are benzaldehyde and phenylacetaldehyde. Its catalytic performance remains stable within five repeated runs and no leaching is noticed for this chromium-based catalyst.

Effect of powder size on the microstructure and dielectric properties of ZnO ceramics

Highlights•Porous structure ZnO ceramics were achieved using high pressure treated powders.•Giant dielectric constant (1.14 × 104 at 100 Hz) was achieved for the sample using ∼300 nm powders.•Ceramics using different size of powders present apparently different micro-structure.

Two-step error-prone bypass of the (+)- and (−)-trans-anti-BPDE-N2-dG adducts by human DNA polymerases η and κ

AbstractBenzo[a]pyrene is a polycyclic aromatic hydrocarbon (PAH) associated with potent carcinogenic activity. Mutagenesis induced by benzo[a]pyrene DNA adducts is believed to involve error-prone translesion synthesis opposite the lesion. However, the DNA polymerase involved in this process has not been clearly defined in eukaryotes. Here, we provide biochemical evidence suggesting a role for DNA polymerase η (Polη) in mutagenesis induced by benzo[a]pyrene DNA adducts in cells. Purified human Polη predominantly inserted an A opposite a template (+)- and (−)-trans-anti-BPDE-N2-dG, two important DNA adducts of benzo[a]pyrene. Both lesions also dramatically elevated G and T mis-insertion error rates of human Polη. Error-prone nucleotide insertion by human Polη was more efficient opposite the (+)-trans-anti-BPDE-N2-dG adduct than opposite the (−)-trans-anti-BPDE-N2-dG. However, translesion synthesis by human Polη largely stopped opposite the lesion and at one nucleotide downstream of the lesion (+1 extension). The limited extension synthesis of human Polη from opposite the lesion was strongly affected by the stereochemistry of the trans-anti-BPDE-N2-dG adducts, the nucleotide opposite the lesion, and the sequence context 5′ to the lesion. By combining the nucleotide insertion activity of human Polη and the extension synthesis activity of human Polκ, effective error-prone lesion bypass was achieved in vitro in response to the (+)- and (−)-trans-anti-BPDE-N2-dG DNA adducts.

Repair of DNA lesions: mechanisms and relative repair efficiencies

AbstractDNA is frequently damaged by endogenous agents inside the cells. Some exogenous agents such as polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the environment and may thus contribute to the `background' DNA damage in humans. DNA lesions are normally removed by various repair mechanisms. The major repair mechanisms for various DNA lesions are summarized. In contrast to the extensively studied repair mechanisms, much less is known about the relative repair efficiencies of various DNA lesions. Since DNA repair is a crucial defense against carcinogenesis, it may constitute an important factor affecting the carcinogenicity of DNA damaging agents. We have adopted a human cell-free system for measuring relative DNA repair efficiencies based on the concept of repair competition between acetylaminofluorene adducts and other DNA lesions of interest. Using this in vitro system, we determined the relative repair efficiencies of PAH adducts induced by: anti-(±)-benzo[a]pyrene-trans-7,8-dihydrodiol-9,10-epoxide (BPDE), anti-(±)-benz[a]anthracene-trans-3,4-dihydrodiol-1,2-epoxide (BADE-I), anti-(±)-benz[a]anthracene-trans-8,9-dihydrodiol-10,11-epoxide (BADE-II), anti-(±)-benzo[b]fluoranthene-trans-9,10-dihydrodiol-11,12-epoxide (BFDE), anti-(±)-chrysene-trans-1,2-dihydrodiol-3,4-epoxide (CDE), and anti-(±)-dibenzo[a,l]pyrene-trans-11,12-dihydrodiol-13,14-epoxide (DBPDE). While damage by BPDE, DBPDE, CDE, and BFDE were repaired by nucleotide excision repair as efficiently as AAF adducts, the repair of BADE-I and BADE-II adducts were significantly slower in human cell extracts. Damage by DBPDE at 3 μM in vitro yielded ∼5-fold higher DNA adducts than BPDE as determined by quantitative PCR. This potent DNA reactivity may account in part for the potent carcinogenicity of dibenzo[a,l]pyrene. The correlation of these results to the carcinogenic properties of the PAH compounds is discussed. Furthermore, we show that NER plays a role in AP site repair in vivo in the eukaryotic model organism yeast.

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