Effect of H2O2 modification of H3PW12O40@carbon for m-xylene oxidation to isophthalic acid

Zhou-wen Fang,Di Wen,Zhi-hao Wang,Xiang-li Long 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.11

The production of isophthalic acid (IPA) from the oxidation of m-xylene (MX) by air is catalyzed by H3PW12O40 (HPW) loaded on carbon and cobalt. We used H2O2 solution to oxidize the carbon to improve the catalytic activity of HPW@C catalyst. Experiments reveal that the best carbon sample is obtained by calcining the carbon at 700oC for 4h after being impregnated in the 3.75% H2O2 solution at 40oC for 7h. The surface characterization displays that the H2O2 modification leads to an increase in the acidic groups and a reduction in the basic groups on the carbon surface. The catalytic capability of the HPW@C catalyst depends on its surface chemical characteristics and physical property. The acidic groups play a more important part than the physical property. The MX conversion after 180min reaction acquired by the HPW@C catalysts prepared from the activated carbon modified in the best condition is 3.81% over that obtained by the HPW@C catalysts prepared from the original carbon. The IPA produced by the former is 46.2% over that produced by the latter.

Effect of activated carbon modified with oxalic acid on the production of IPA from MX catalyzed by H3PW12O40@carbon and cobalt

Zhou-wen Fang,Hua-jie Liu,Zhi-hao Wang,Di Wen,Xiang-li Long 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.68 No.-

The production of IPA from the oxidation of MX is completed under the catalysis of H3PW12O40 (HPW) loaded on carbon and cobalt. Oxalic acid is tried to modify the carbon to upgrade the catalytic activity of HPW@C catalyst. The experiments show that the best carbon is acquired by carbonizing the carbon at 450 °C for 2 h in N2 after being soaked in a 0.20 mol l−1 oxalic acid solution for 16 h. The IPA produced by the HPW@C catalysts prepared with the carbon modified is 58.9% over that obtained by the catalysts prepared with the original carbon.

Measurement of neutron cross sections and resonance parameters of ¹⁶⁹Tm below 100 eV

Wen-Ming, Wang,Xia, Li,Zhi-Xiang, Zhao,Zu-Ying, Zhou,Hong-Wei, Yu,Hai-Cheng, Wu,Yi-Xiang, Wei,Wang, T. F.,Kim, G. N.,Lee, M. W.,Kim, K. S.,Cho, M. H.,Ko, I. S.,Namkung, W. science press 2010 Chinese physics. C Vol.34 No.2

<P>The neutron total cross-sections of thulium (<SUP>169</SUP>Tm) were measured in the neutron energy region from 0.01 eV to 100 eV by using the time-of-flight method at the Pohang Neutron Facility, which consists of an electron linac, a water-cooled tantalum target with a water moderator, and a 12 m time of flight path. Two thulium plates with different thicknesses were used for the neutron transmission measurement. The background level was determined by using a notch-filter of Co, In, and Cd sheets. The present measurement was compared with the previous ones, and a new set of resonance parameters of <SUP>169</SUP>Tm isotope was obtained from the transmission rate by using the SAMMY code, with a comparison with the recommended parameters by Mughabghab.</P>

Preferential Induction of CYP1A1 over CYP1B1 in Human Breast Cancer MCF-7 Cells after Exposure to Berberine

Wen, Chun-Jie,Wu, Lan-Xiang,Fu, Li-Juan,Shen, Dong-Ya,Zhang, Xue,Zhang, Yi-Wen,Yu, Jing,Zhou, Hong-Hao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

Estrogens are considered the major breast cancer risk factor, and the carcinogenic potential of estrogens might be attributed to DNA modification caused by derivatives formed during metabolism. $17{\beta}$-estradiol ($E_2$), the main steroidal estrogen present in women, is metabolized via two major pathways: formation of 2-hydroxyestradiol (2-OH $E_2$) and 4-hydroxyestradiol ($4-OH\;E_2$) through the action of cytochrome P450 (CYP) 1A1 and 1B1, respectively. Previous reports suggested that $2-OH\;E_2$ has putative protective effects, while $4-OH\;E_2$ is genotoxic and has potent carcinogenic activity. Thus, the ratio of $2-OH\;E_2/4-OH\;E_2$ is a critical determinant of the toxicity of $E_2$ in mammary cells. In the present study, we investigated the effects of berberine on the expression profile of the estrogen metabolizing enzymes CYP1A1 and CYP1B1 in breast cancer MCF-7 cells. Berberine treatment produced significant induction of both forms at the level of mRNA expression, but with increased doses produced 16~ to 52~fold greater induction of CYP1A1 mRNA over CYP1B1 mRNA. Furthermore, berberine dramatically increased CYP1A1 protein levels but did not influence CYP1B1 protein levels in MCF-7 cells. In conclusion, we present the first report to show that berberine may provide protection against breast cancer by altering the ratio of CYP1A1/CYP1B1, could redirect $E_2$ metabolism in a more protective pathway in breast cancer MCF-7 cells.

Clinical Observation of Three Dimensional Conformal Radiotherapy with Tamoxifen in Treatment of Postoperative Malignant Glioma

Zhou, Shao-Bing,Liu, Yang-Chen,Yin, Xiao-Xiang,Ding, Wen-Xiu,Guo, Xin-Wei,Gu, Liang,Huang, Xin-En Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

Objective: To evaluate the efficacy and adverse effects of three dimensional conformal radiotherapy (3D-CRT) with tamoxifen in treating patients with postoperative malignant glioma. Patients and Methods: 60 patients of postoperative malignant glioma were randomly assigned into two groups, 30 patients were treated with 3D-CRT plus tamoxifen (treatment group), and the other 30 patients with 3D-CRT plus temozolomide (control group). All patients were radiated by 6MV X-ray, 2.0Gy per fraction, once daily, with a total dose (DT) of 56~60Gy. Tamoxifen was delivered at $60mg/m^2/d$, temozolomide was given at $75mg/m^2/d$. All patients were treated with concurrent radiotherapy. Results: One, 2, 3 year survival rates of treatment and control group were 63.3%, 30.0%, 23.0% and 70.0%, 33.3%, 26.7%, respectively (${\chi}^2=0.01$, 0.23, 0.09, P>0.05). The rate of thromboembolism in treatment group was 6.7%. Conclusion: Therapeutic efficacy of two groups was similar, but it was more cost-effective in treatment group, and toxicity did not increase.

Genomic Screening for Targets Regulated by Berberine in Breast Cancer Cells

Wen, Chun-Jie,Wu, Lan-Xiang,Fu, Li-Juan,Yu, Jing,Zhang, Yi-Wen,Zhang, Xue,Zhou, Hong-Hao Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Berberine, a common isoquinoline alkaloid, has been shown to possess anti-cancer activities. However, the underlying molecular mechanisms are still not completely understood. In the current study, we investigated the effects of berberine on cell growth, colony formation, cell cycle distribution, and whether it improved the anticancer efficiency of cisplatin and doxorubicin in human breast cancer estrogen receptor positive (ER+) MCF-7 cells and estrogen receptor negative (ER-) MDA-MB-231 cells. Notably, berberine treatment significantly inhibited cell growth and colony formation in the two cell lines, berberine in combination with cisplatin exerting synergistic growth inhibitory effects. Accompanied by decreased growth, berberine induced G1 phase arrest in MCF-7 but not MDA-MB-231 cells. To provide a more detailed understanding of the mechanisms of action of berberine, we performed genome-wide expression profiling of berberine-treated cells using cDNA microarrays. This revealed that there were 3,397 and 2,706 genes regulated by berberine in MCF-7 and MDA-MB-231 cells, respectively. Fene oncology (GO) analysis identified that many of the target genes were involved in regulation of the cell cycle, cell migration, apoptosis, and drug responses. To confirm the microarray data, qPCR analysis was conducted for 10 selected genes based on previously reported associations with breast cancer and GO analysis. In conclusion, berberine exhibits inhibitory effects on breast cancer cells proliferation, which is likely mediated by alteration of gene expression profiles.

Thiamethoxam Induces Meiotic Arrest and Affects Embryo Developmental Potential of Bovine Oocytes

Zheng-Wen Nie,Ying-Jie Niu,Wenjun Zhou,Yong-Han Kim,Kyung-Tae Shin,Xiang-Shun Cui 한국수정란이식학회 2018 한국수정란이식학회 학술대회 Vol.2018 No.11

Thiamethoxam (TMX) is a neonicotinoid insecticide. Residues of TMX have been detected in various crops. Although it has specific high toxicity to insects and is designed to exterminate them, the toxicity has also found in mammals recently. Differ from acetylcholine toxicity, TMX has peroxide toxicity in mammals. Matured oocytes have the capacity of fertilization, but oocytes own abundant mitochondria and its maturation is vulnerable to reactive oxygen species (ROS). Excessive production of reactive oxygen species (ROS) can override antioxidant defenses, produce oxidative stress and DNA damage that triggers apoptosis and necrosis in organisms. However little is known about the harm of ROS induced by TMX during oocytes maturation. Here, bovine germ-vesicle (GV) oocytes were cultured to metaphase of the second meiosis (MII) stage in vitro with or without TMX. During this process, oocytes were evaluated by various methods. Microscopic examination showed that 1.6 mM TMX significantly inhibited the maturation process in which oocytes were arrested before MI stage or between MI and MII stage. Correspond to this two periods, immunofluorescence staining and enzyme activity analysis showed that active CDC25 and CDC2 reduced in TMX group compared to control; time lapse and immunofluorescence staining gave results that Cyclin B could not be degraded, actin cap could not form, and Bub3 could not be removed from kinetochores. In addition, MII oocytes exposed to TMX showed disordered chromosomes and spindle. To study further, oocytes cultured for 24 h were analyzed. On the one hand, these oocytes in TMX group accumulated more ROS and produced significantly decreased mitochondrial membrane potential and increased apoptotic signal compared to control by methods of quantities for dichlorodihydrofluorescein diacetate (DCHFDA), 5,5′,6,6′-Tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine iodide and Annexin-V, but the level of γH2AX protein in TMX group did not decline significantly compared with control. On the another hand, these oocytes were activated to be parthenogenetic embryos and cultured. Assessment for embryo development showed decreased rates of cleavage, morula and blastocyst in TMX group compared to control in vitro. In conclusion, these results suggest that ROS induced by TMX results in dysfunction of mitochondria and apoptosis, which block bovine oocytes to MI stage, trap them at AI/TI stage and trigger disordered chromosomes and spindle at MII stage. Additionally, MII oocytes with poor qualities result from TMX lose abilities to cleavage and develop to be morulae and blastocysts.

Active current-limiting control to handle DC line fault of overhead DC grid

MENG Zhou,WANG Xiang,WENPING Zuo,WEIXING Lin,JINYU Wen,RUIZHANG Yang,BINYE Ni,XIAOJUN Lu 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

To handle with the DC line faults in a DC grid, this paper proposed an active current-limiting controller for hybrid MMC. With this active current-limiting control strategy, the requirement of interruption current of DCCB will be significantly decreased, and the investment of DC grid will be reduced obviously. Firstly, the control architecture of active current-limiting controller is disclosed. To avoid the overvoltage of submodule capacitors during DC fault, a dynamic limiter for the reference value of the DC current controller is proposed. To decrease the peak of fault current, the feedforward controller of DC voltage is put forward. The decoupling controllability of the AC/DC voltage of hybrid MMC is disclosed. The currentlimiting mechanism of the active current-limiting controller is analysis. Then, the validity of the active current-limiting control strategy is verified by RTDS.

Syntheses, Structure, and Properties of Four Metal-Organic Polymers Based on Rigid Multiple Carboxylate Ligands and N-Donor Ligands

Yong Zhou,Wen-Hao Zhao,Jin Wang,Jin-Rui Wei,Xian-Hong Yin,Xiang-Bo Wei,Cui-Wu Lin 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.11

Four metal-organic coordination polymers, {[Cd2(BIBP)2(H2DTDA)2]n  · 2(H2O)} (1), [Zn (BIBP) (H2TDA)2] n (2), [Cd2(BIBP)(H2TDA)2] n (3), and [Ni2(BIBP)2(H2DTDA)2(μ-O)] n , (4) [where BIBP = 4,4′-bis(1-imidazoly)biphenyl, H2TDA = [1,1′:4′1″-terphen-yl]-3,3″-dicarboxylic acid, and H2DTDA = 2′,5′-dimethyl-[1,1′:4′,1″-terphenyl]-3,3″-dicarboxylic acid] were hydrothermally synthesized and characterized by elemental analyses, IR, TG, luminescence, and single crystal X-ray diffraction. X-Ray diffraction analysis reveals that the four complexes exhibit new frameworks due to diverse coordination conformations. The different coordination modes of the ligands BIBP and two aromatic carboxylate acids play important roles in the construction of the final structure for the complexes. X-ray structure analysis reveals that 1, 2, and 4 are 3D coordination polymers, while complex 3 is a 2D network polymer.

Nuclear Transportation of Pyruvate Dehydrogenase Controls the Zygotic Genome Activation in Pig

Wenjun Zhou,Ying-Jie Niu,Zheng-Wen Nie,Kyung-Tae Shin,Yong-Han Kim,Xiang-Shun Cui 한국수정란이식학회 2018 한국수정란이식학회 학술대회 Vol.2018 No.11

The porcine zygotic genome activation occurs along with global epigenetic remolding at the 4-cell stage. The histone acetylation, regulating DNA transcription, replication and so on, requires adequate acetyl-CoA. Acetyl-CoA produced by translocated pyruvate dehydrogenase in the nucleus of mammalian cells has been reported, which is commonly considered locating in the mitochondria. To find out whether the nuclear pyruvate dehydrogenase regulating the histone acetylation by controlling generation of acetyl-CoA, a multiple sgRNAs-CRISPR/Cas9 targeting strategy was employed to generate a pyruvate dehydrogenase E1 alpha1 (Pdha1) knockout (KO) parthenogenetic embryo model. Results showed that the targeting efficiency of Pdha1 reached more than 90%. Hence, this model was used in the subsequent experiments. Furthermore, a translocation of Pdha1 during zygotic genome activation was found by immunofluorescent staining and was significantly inhibited by Pdha1 KO. Meanwhile, the 8-cell stage embryo rate significantly decreased after 72 h (24.19% vs 12.53%, control vs Pdha1 KO), indicating a 4-cell arrest. In addition, the nuclear histone acetylation level significantly decreased when Pdha1 was KO. To determine whether the zygotic genome transcription was affected, the qPCR was performed and showed that the mRNA level of Eif1A, Acly, Sqle and Pdha1 all dropped significantly in the Pdha1 KO group compared to the control. In conclusion, the translocated Pdha1 generates acetyl-CoA for histone acetylation inside the nucleus of porcine embryos, which promotes the zygotic genome activation of porcine embryos.