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Synthesis and X-ray Crystal Structure of a New Manganese 18-Metallacrown-6

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Wuhan University Journal of Natural Sciences 2004年第1期9卷 93-98页

作者： HanDong-dong ChengGong-zhen Jizhen-ping ZhangBing-guang CollegeofChemistryandMolecularSciences WuhanUniversityWuhan430072HubeiChina TheStateKeyLaboratoryofCoordinationChemistry NanjingUniversityNanjing210093JiangsuChina

A new hexanuclear manganese (III) azametallacrown, [Mn6 (anhz)6 (DMF)2 (H2O)4]·8DMF was synthesized using trianionic pentadentate ligand, N-acetyl-3-hydroxy-2-naphthoic acid hydrazide (anhz3?), and characterized by X-ray single crystal diffraction. The deprotonated ligand bridges the metal ions using the N?N group of hydrazide to form an 18-membered-ring that has M?N?N repeating units and a cavity in the center. The stereochemistry of the compound has an alternating Δ/Λ propeller configuration. Key words azametallacrown - manganese - crystal structure - pentadentate - hydrazide - synthesis CLC number O 614.7 Foundation item: Supported by the National Natural Science Foundation of China (20171035), The Natural Science Foundation of Hubei ProvinceBiography: Han Dong-dong (1977-), female, Master, research direction: inorganic chemistry

关键词： azametallacrown manganese crystal structure pentadentate hydrazide synthesis

Role of epigenetics in transformation of inflammation into colorectal cancer

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World Journal of Gastroenterology 2019年第23期25卷 2863-2877页

作者： zhen-Hua Yang Yan-Qi Dang guang Ji Institute of Digestive Diseases Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China Digestive Endoscopy Department Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China

Molecular mechanisms associated with inflammation-promoted tumorigenesis have become an important topic in cancer research. Various abnormal epigenetic changes, including DNA methylation, histone modification, chromatin remodeling, and noncoding RNA regulation, occur during the transformation of chronic inflammation into colorectal cancer(CRC). These changes not only accelerate transformation but also lead to cancer progression and metastasis by activating carcinogenic signaling pathways. The NF-κB and STAT3 signaling pathways play a particularly important role in the transformation of inflammation into CRC, and both are critical to cellular signal transduction and constantly activated in cancer by various abnormal changes including epigenetics. The NF-κB and STAT3 signals contribute to the microenvironment for tumorigenesis through secretion of a large number of pro-inflammatory cytokines and their crosstalk in the nucleus makes it even more difficult to treat CRC. Compared with gene mutation that is irreversible, epigenetic inheritance is reversible or can be altered by the intervention. Therefore, understanding the role of epigenetic inheritance in the inflammation-cancer transformation may elucidate the pathogenesis of CRC and promote the development of innovative drugs targeting transformation to prevent and treat this malignancy. This review summarizes the literature on the roles of epigenetic mechanisms in the occurrence and development of inflammation-induced CRC. Exploring the role of epigenetics in the transformation of inflammation into CRC may help stimulate futures studies on the role of molecular therapy in CRC.

关键词： Colorectal cancer Inflammation DNA methylation Histone modification LncRNA MicroRNAs Epigenetics

The ornithine-urea cycle involves fumaric acid biosynthesis in Aureobasidium pullulans ***,a green and eco-friendly process for fumaric acid production

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Synthetic and Systems Biotechnology 2023年第1期8卷 33-45页

作者： Xin Wei Miao Zhang guang-Yuan Wang guang-Lei Liu zhen-Ming Chi Zhe Chi College of Marine Life Sciences Ocean University of ChinaYushan RoadNo.5QingdaoChina Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology266003China College of Life Science Shandong Province Key Laboratory of Applied MycologyQingdao Agricultural UniversityQingdao266109China

The current petroleum chemical methods for fumaric acid production can cause heavy pollution and global *** this study,the engineered strains of *** *** were found to be suitable for green fumaric acid *** and complementation of the relevant genes showed only the ornithine-urea cycle(OUC)was involved in high level fumarate biosynthesis which was controlled by the Ca^(2+)signaling *** of both the GOX gene encoding glucose oxidase and the PKS1 gene encoding the polyketide synthase for 3,5-dihydroxydecanoic acid biosynthesis and overexpression of the PYC gene encoding pyruvate carboxylase made the strain e-PYC produce 88.1±4.3 g/L of fumarate at flask level and 93.9±0.8 g/L of fumarate during the fed-batch *** a yeast-like fungal strain,it was very easy to cultivate *** *** DH177 and their mutants in the bioreactor and to edit its genomic DNAs to enhance fumarate *** was found that 2 mol of CO_(2) could be fixed during a maximal theoretical yield of 2 mol of fumarate per mole of glucose consumed in the ***,the OUC-mediated fumarate biosynthesis pathway in *** *** was a green and eco-friendly process for the global sustainable development and carbon neutrality.

关键词： Fumaric acid A.pullulans var.aubasidani Ornithine-urea cycle Ca^(2+)signaling pathway

Role of COX-2 in carcinogenesis of colorectal cancer and its relationship with tumor biological characteristics and patients' prognosis

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World Journal of Gastroenterology 2003年第9期9卷 1990-1994页

作者： Ai-WenWu JinGu Jia-FuJi zhen-FuLi guang-WeiXu DepartmentofSurgery PekingUniversitySchoolofOncologyBeijingCancerHospitalBeijingInstituteforCancerResearchBeiiing100036China DepartmentofBiochemistry PekingUniversitySchoolofOncologyBeijingCancerHospitalBeijingInstituteforCancerResearchBeijing100036China

AIM: Recent clinical epidemiological studies havedemonstrated the preventive effect of non-steroidal anti-inflammatory drugs (NSAIDs) against colorectal *** underlying mechanism might be the inhibition of rate-limiting enzyme cyclooxygenase-2 (COX-2) in metabolismof arachidonic acid. The role of COX-2 in carcinogenesisof colorectal cancer and its relationship with tumorbiological characteristics and patients′ prognosis stillremain unclear. This study was to investigate the role ofCOX-2 expression in carcinogenesis of colorectal cancerand its relationship with tumor biological characteristicsand patients′ ***: A total of 139 colorectal cancers and 19adenomas surgically treated in School of Oncology, PekingUniversity, from January 1993 to September 2001 wereretrospectively studied. COX-2 expression was detected withtissue microarray (TMA) and immunohistochemistry (IHC)procedure. The association between COX-2 expression andclinicopathological features and its influence on patients′prognosis were ***: COX-2 expression was strong in colorectal cancer,moderate in adenoma and weak in normal mucosa, whichdemonstrated statistically significant difference (x2=46.997,P＜0.001). COX-2 expression had no association withclinicopathological features such as gross type,differentiation, invasion depth, vessel emboli and TNMstaging. Cox proportional hazards modeling analysis and Logrank test revealed no prognostic role of COX-2 expressionin colorectal cancer ***: COX-2 may play an important role in theearly stage of carcinogenesis, and its expression in colorectalcancer is not associated with clinicopathological features and patients′ prognosis.

关键词：结肠直肠癌生物学特征环氧合酶-2 肿瘤发生预后

Identification of transporter proteins for PQQ-secretion pathways by transcriptomics and proteomics analysis in Gluconobacter oxydans WSH-003

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Frontiers of Chemical Science and Engineering 2017年第1期11卷 72-88页

作者： Hui Wan Yu Xia Jianghua Li zhen kang Jingwen Zhou School of Biotechnology and Key Laboratory of Industrial B iotechnology Ministry of Education Jiangnan University Wuxi 214122 China Synergetic Innovation of Center of Food Safety and Nutrition Jiangnan University Wuxi 214122 China

Pyrroloquinoline quinone （PQQ） plays a sig- nificant role as a redox cofactor in combination with dehydrogenases in bacteria. These dehydrogenases play key roles in the oxidation of important substrates for the biotechnology industry, such as vitamin C production. While biosynthesis of PQQ genes has been widely studied, PQQ-transport mechanisms used both two-dimensional remain unclear. Herein, we fluorescence-difference gel electrophoresis tandem mass spectrometry and RNA sequencing to investigate the effects ofpqqB overexpres- sion in an industrial strain of Gluconobacter oxydans WSH-003. We have identified 73 differentially expressed proteins and 99 differentially expressed genes, a majority of which are related to oxidation-reduction and transport processes by gene ontology analysis. We also described several putative candidate effectors that responded to increased PQQ levels resulting from pqqB overexpression. Furthermore, quantitative PCR was used to verify five putative PQQ-transport genes among different PQQ producing strains, and the results showed that ompW, B932 1930 and B932_2186 were upregulated in all conditions. Then the three genes were over-expressed in G. oxydans WSH-003 and PQQ production were detected. The results showed that extracellular PQQ of B932_1930 （a transporter） and B932_2186 （an ABC transporter perrnease） overexpression strains were enhanced by 1.77- fold and 1.67-fold, respectively. The results suggest that the proteins encoded by PqqB, B932_1930 and B932 2186 might enhance the PQQ secretion process.

关键词： 2D-DIGE pqqB pyrroloquinoline quinone,RNA-Seq Vitamin C

Priority-based IEEE 802.15.4 CSMA/CA mechanism for WSNs

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The Journal of China Universities of Posts and Telecommunications 2013年第1期20卷 47-53页

作者： ZHAO Lu BAI guang-wei SHEN Hang TANG zhen-min Key Laboratory of Intelligent Perception and System for High-dimensional Information for Ministry of Education of China Nanjing University of Science and Technology School of Electronics and Information Engineering Nanjing University of Technology

The IEEE 802.15.4 standard is widely used in wireless sensor networks （WSNs）. In this paper, we propose a priority-based IEEE 802.15.4 carrier sense multiple access with collision avoidance （CSMA/CA） mechanism for WSNs. Considering traffic load and traffic type of sensor nodes, we classify sensor nodes into three types. In our mechanism, different contention parameters are set for nodes with different priority levels, in order that nodes with high priority achieve high probability to access the channel. By modeling the proposed mechanism using a Markov chain, we analyze and compute the successful transmission probability, throughput and energy consumption for nodes with different priority levels. Finally, our numerical results demonstrate that our mechanism performs well for WSNs.

关键词： WSNs 1EEE 802.15.4 MAC Markov chain priority real-time data

Separation of mandelic acid and its derivatives with new immobilized cellulose chiral stationary phase

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第7期14卷 615-620页

作者： Jie ZHOU Qian LIU guang-jun FU zhen-zhong ZHANG Key Laboratory of State Ministry of Education for Pharmaceutical Technology School of Pharmacy Zhengzhou University

A new liquid chromatographic method has been developed for the chiral separation of the enantiomers of mandelic acid and their derivatives 2-chloromandelic acid, 4-hydroxymandelic acid, 4-methoxymandelic acid, and 3,4,5-trismethoxymandelic acid. The enantiomers were separated by a CHIRALPAKIC (250 mm×4.6 mm, 5 μm). Mandelic acid, 4-methoxymandelic acid, and 3,4,5-trismethoxymandelic acid were baseline resolved (resolution factor (RS )=2.21, RS =2.14, and RS =3.70, respectively). In contrast, the enantioselectivities between CHIRALPAKIC and 2-chloromandelic acid and 4-hydroxymandelic acid investigated were low. By comparing the chromatographs of mandelic acid enantiomers and mandelic acid spiked with (R)-mandelic acid, it was determined that the first effluent was (R)-mandelic acid.

关键词： CHIRALPAKIC Enantiomeric separation High-performance liquid chromatography (HPLC) Mandelic acid Derivatives

Effects of Heat Treatment on Surface Recrystallization and Stress Rupture Properties of a Fourth-Generation Single-Crystal Superalloy after Grit Blasting

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Acta Metallurgica Sinica(English Letters) 2017年第7期30卷 614-620页

作者： zhen-Xue Shi Shi-Zhong Liu Xiao-guang Wang Jia-Rong Li Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials Beijing 100095 China

The specimens of a fourth-generation single-crystal superalloy were grit-blasted and heat-treated in vacuum at 1100, 1150, 1200, 1250 and 1300 °C for 4 h, respectively. Then, the microstructure and the stress rupture properties of the recrystallized alloy were investigated at 1150 °C/120 MPa. The results showed that a cellular recrystallization occurred in the surface layer after heating at 1100, 1150 and 1200 °C for 4 h. An equiaxed recrystallization formed as the specimen was heat-treated at 1300 °C for 4 h, while a mixed recrystallization occurred in the specimen heat-treated at 1250 °C for 4 h. The recrystallized depth clearly increased with a rise of the heat treatment temperature. The stress rupture life continuously decreased with a rise of the heat treatment temperature up to 1250 °C. Although the overall stress rupture life reduced to different degrees, the stress rupture life of specimen after heat treatment at 1300 °C was relatively high and intermediate between those of specimens treated at 1150 and 1200 °C. The fact that the stress rupture life reduced to different degrees after heat treatment can be attributed to the recrystallization of the surface layer and to the microstructure evolution of the interior of the specimen. The small γ’ phase precipitated again after heat treatment at 1300 °C for 4 h. So,the stress rupture life was relatively longer than that after heat treatment at 1200 or 1250 °C although the equiaxed recrystallization formed in the surface layer.

关键词： Single-crystal superalloy Heat treatment Recrystallization Stress rupture properties

X-ray repair cross-complementing group 1 polymorphisms and hepatocellular carcinoma:A meta-analysis

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World Journal of Gastroenterology 2012年第31期18卷 4207-4214页

作者： Tian Xie zhen-guang Wang Jing-Lei Zhang Hui Liu Department of Hepatic Surgery National Hepatobiliaryand Enteric Surgery Research Center Ministry of Health CentralSouth University Changsha 410008 Hunan Province China Department ofHepatic Surgery Eastern Hepatobiliary Surgery Hospital Sec-ond Military Medical University Shanghai 200438 China

AIM： To perform a systematic meta-analysis to in- vestigate the association between X-ray repair crosscomplementing group 1 （XRCC1） polymorphisms and hepatocellular carcinoma （HCC） risk. METHODS： Relevant studies extracted from PubMed, Embase, Wanfang, VIP and the Chinese National Knowledge Infrastructure databases up to March 2012 were included in the study. Stata software, version 11.0, was used for the statistical analysis. The odds ratios （ORs） and 95% confidence interval （CI） of the XRCC1 polymorphisms in HCC patients were analyzed and compared with healthy controls. The meta-analysis was performed using fixed-effect or random-effect methods, depending on the absence or presence of significant heterogeneity. RESULTS： Eleven studies with 2075 HCC cases and 2604 controls met our eligibility criteria （four studies, 888 cases and 938 controls for Arg194Trp, four studies, 858 cases and 880 controls for Arg280His, and nine studies, 1845 cases and 2401 controls for Arg399Gln）. The meta-analysis revealed no associations between the Arg194Trp and Arg399GIn polymorphisms of the XRCC1 gene and HCC risk under all contrast models （codominant, dominant and recessive models） in the overall analysis and sensitivity analysis （the studies with controls not in the Hardy-Weinberg equilibrium were excluded）. For XRCC1 Arg280His polymorphism, the overall analysis revealed the significant associa- tion between the His/His genotype and the increased risk of HCC （His/His vs Arg/Arg model, OR： 1.96, 95% CI： 1.03-3.75, P = 0.04）. However, sensitivity analysis showed an altered pattern of result and non-significant association （OR： 2.06, 95% CI： 0.67-6.25, P = 0.20）. The heterogeneity hypothesis test did not reveal any heterogeneity, and Begg＇s and Egger＇s tests did not find any obvious publication bias. CONCLUSION： The XRCC1 Arg194Trp and Arg399GIn polymorphisms are not associated with HCC risk. More rigorous association studies are needed to verify the involvement ofXRCC1 Arg280His poly

关键词： X-ray repair cross-complementing group 1 Polymorphism Hepatocellular carcinoma Meta-analysis