Molecular Cloning and Bioinformatic Analysis of SPATA4 Gene

Liu, Shang-Feng,Ai, Chao,Ge, Zhong-Qi,Liu, Hai-Luo,Liu, Bo-Wen,He, Shan,Wang, Zhao Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.6

Full-length cDNA sequences of four novel SPATA4 genes in chimpanzee, cow, chicken and ascidian were identified by bioinformatic analysis using mouse or human SPATA4 cDNA fragment as electronic probe. All these genes have 6 exons and have similar protein molecular weight and do not localize in sex chromosome. The mouse SPATA4 sequence is identified as significantly changed in cryptorchidism, which shares no significant homology with any known protein in swissprot databases except for the homologous genes in various vertebrates. Our searching results showed that all SPATA4 proteins have a putative conserved domain DUF1042. The percentages of putative SPATA4 protein sequence identity ranging from 30% to 99%. The high similarity was also found in 1 kb promoter regions of human, mouse and rat SPATA4 gene. The similarities of the sequences upstream of SPATA4 promoter also have a high proportion. The results of searching SymAtlas (http://symatlas.gnf.org/SymAtlas/) showed that human SPATA4 has a high expression in testis, especially in testis interstitial, leydig cell, seminiferous tubule and germ cell. Mouse SPATA4 was observed exclusively in adult mouse testis and almost no signal was detected in other tissues. The pI values of the protein are negative, ranging from 9.44 to 10.15. The subcellular location of the protein is usually in the nucleus. And the signal peptide possibilities for SPATA4 are always zero. Using the SNPs data in NCBI, we found 33 SNPs in human SPATA4 gene genomic DNA region, with the distribution of 29 SNPs in the introns. CpG island searching gives the data about CpG island, which shows that the regions of the CpG island have a high similarity with each other, though the length of the CpG island is different from each other.This research is a fundamental work in the fields of the bioinformational analysis, and also put forward a new way for the bioinformatic analysis of other genes.

Optimization Model of Reliable Data Storage in Cloud Environment Using Genetic Algorithm

Feng Liu,Haitao Wu,Xiaochun Lu,Xiyang Liu 보안공학연구지원센터 2014 International Journal of Grid and Distributed Comp Vol.7 No.6

Massive data storage is one of the great challenges for cloud computing service, and reliable storage of sensitive data directly affects quality of storage service. In this paper, based on analysis of data storage process in cloud environment, the cost of massive data storage is considered to be comprised of data storage price, data migration and communication; and the storage reliability consists of data transmission reliability and hardware dependability. A multi-objective optimization model for reliable massive storage is proposed, in which storage cost and reliability are the objectives. Then, a genetic algorithm for solving the model is designed. Finally, experimental results indicate that the proposed model is positive and effective.

Molecular Cloning and Bioinformatic Analysis of SPATA4 Gene

Shang Feng Liu,Chao Ai,Zhong Qi Ge,Hai Luo Liu,Bo Wen Liu,Shan He,Zhao Wang 한국생활환경학회 2005 BMB Reports Vol.38 No.6

Cloning and Functional Characterization of Putative Escherichia coli ABC Multidrug Efflux Transporter YddA

( Zhenyue Feng ),( Defu Liu ),( Ziwen Liu ),( Yimin Liang ),( Yanhong Wang ),( Qingpeng Liu ),( Zhenhua Liu ),( Zhongjing Zang ),( Yudong Cui ) 한국미생물 · 생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.7

A putative multidrug efflux gene, yddA, was cloned from the Escherichia coli K-12 strain. A drugsensitive strain of E. coli missing the main multidrug efflux pump AcrB was constructed as a host and the yddA gene was knocked out in wild-type (WT) and drug-sensitive E. coliΔacrB to study the yddA function. Sensitivity to different substrates of WT E.coli, E. coliΔyddA, E. coliΔacrB and E. coliΔacrBΔyddA strains was compared with minimal inhibitory concentration (MIC) assays and fluorescence tests. MIC assay and fluorescence test results showed that YddA protein was a multidrug efflux pump that exported multiple substrates. Three inhibitors, ortho-vanadate, carbonyl cyanide m-chlorophenylhydrazone (CCCP), and reserpine, were used in fluorescence tests. Ortho-vanadate and reserpine significantly inhibited the efflux and increased accumulation of ethidium bromide and norfloxacin, while CCCP had no significant effect on YddA-regulated efflux. The results indicated that YddA relies on energy released from ATP hydrolysis to transfer the substrates and YddA is an ABC-type multidrug exporter. Functional study of unknown ATP-binding cassette (ABC) superfamily transporters in the model organism E. coli is conducive to discovering new multidrug resistance-reversal targets and providing references for studying other ABC proteins of unknown function.

Influence of the camber trailing-edge wings on the motion performance of underwater gliders

Liu Yuhong,Xu Shixun,Tian Shan,Lan Shiquan,Deng Shihan,Liu Shuhe,Feng Dengxue 대한조선학회 2022 International Journal of Naval Architecture and Oc Vol.14 No.1

Wings are the main source of lift for Underwater Gliders (UGs) and play a decisive role in their motion performance. The wings of UGs are generally rectangular and symmetrical airfoils. In this study, a mini- UG with flexible camber trailing-edge wings was proposed and developed to investigate the influence of the trailing edge of the wings on the motion performance of UGs. Flexible deformation of the trailing edge was realized using a steer-by-wire actuator. The test results showed that the trailing edge of the wing could realize maximum upward/downward sloping angles of þ16/16. By combining computational fluid dynamics simulations and tank experiments, this study obtained the glide efficiency (in liftdrag ratio) and stable margins of a mini-UG with variable camber trailing-edge wings. The results showed that the angles of attack corresponding to the minimum lift-to-drag ratio were all negative in cases of downward sloping and positive in cases of upward sloping. Moreover, the suitable camber of the trailing edge, that is, downward-sloping trailing edge on descending glides and upward-sloping trailing edge on ascending glides, can not only greatly improve glide efficiency but also benefit flight stability. Tank experiments showed that the lift-to-drag ratio of the mini-UG with appropriate variable camber trailing-edge wings can be increased by at least 25% compared to those with a symmetrical airfoil.

LncRNA H19 Drives Proliferation of Cardiac Fibroblasts and Collagen Production via Suppression of the miR-29a-3p/miR-29b-3p-VEGFA/TGF-β Axis

Feng Guo,Chengchun Tang,Bo Huang,Lifei Gu,Jun Zhou,Zongyang Mo,Chang Liu,Yuqing Liu 한국분자세포생물학회 2022 Molecules and cells Vol.45 No.3

The aim of this study was to investigating whether lncRNA H19 promotes myocardial fibrosis by suppressing the miR-29a-3p/miR-29b-3p-VEGFA/TGF-β axis. Patients with atrial fibrillation (AF) and healthy volunteers were included in the study, and their biochemical parameters were collected. In addition, pcDNA3.1-H19, si-H19, and miR-29a/b-3p mimic/inhibitor were transfected into cardiac fibroblasts (CFs), and proliferation of CFs was detected by MTT assay. Expression of H19 and miR-29a/b-3p were detected using real-time quantitative polymerase chain reaction, and expression of α-smooth muscle actin (α-SMA), collagen I, collagen II, matrix metalloproteinase-2 (MMP-2), and elastin were measured by western blot analysis. The dual luciferase reporter gene assay was carried out to detect the sponging relationship between H19 and miR-29a/b-3p in CFs. Compared with healthy volunteers, the level of plasma H19 was significantly elevated in patients with AF, while miR-29a-3p and miR-29b-3p were markedly depressed (P < 0.05). Serum expression of lncRNA H19 was negatively correlated with the expression of miR-29a-3p and miR-29b-3p among patients with AF (rs = –0.337, rs = –0.236). Moreover, up-regulation of H19 expression and down-regulation of miR-29a/b-3p expression facilitated proliferation and synthesis of extracellular matrix (ECM)-related proteins. SB431542 and si-VEGFA are able to reverse the promotion of miR-29a/b-3p on proliferation of CFs and ECM-related protein synthesis. The findings of the present study suggest that H19 promoted CF proliferation and collagen synthesis by suppressing the miR-29a-3p/miR-29b-3p-VEGFA/TGF-β axis, and provide support for a potential new direction for the treatment of AF.

Research on the dispersion of carbon nanotubes and their application in solution-processed polymeric matrix composites: A review

Feng, Tao,Liu, Neng,Wang, Shunjie,Qin, Can,Shi, Shengwei,Zeng, Xueying,Liu, Gang Techno-Press 2021 Advances in nano research Vol.10 No.6

This review highlights and categorizes the approaches for preparation of CNTs dispersion and polymer/CNTs composites via solution-based strategies. Carbon nanotubes (CNTs) demonstrate unique physical and chemical properties, which allow several exciting potential applications in various fields including nanocomposites. Presently, the commercialized application of CNTs is still quite limited due to the formation of CNTs bundles, which significantly degrade the properties. Therefore, well dispersion of CNTs in nanocomposites is quite important, especially for CNTs/polymer composites, as a small amount of CNTs can improve the composite properties dramatically. This article will review the research on the dispersion of CNTs (including covalent and non-covalent functionalization) and the fabrication of CNTs/polymer composites through solution-based strategies by using the CNT dispersions. Moreover, the factors influencing the properties of CNTs/polymer composites will be discussed as well as the future outlook.

Further Study on Pemetrexed based chemotherapy in Treating Patients with Advanced Gastric Cancer (AGC)

Liu, Jin,Huang, Xin-En,Feng, Ji-Feng Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Objective: To further observe the efficacy and safety of pemetrexed, combined with Irinotecan or oxaliplatin or cisplatin in treating patients with advanced gastric cancer as second-line or third-line chemotherapy. Methods: From September 2013 to February 2014 we recruited 50 patients with advanced gastric cancer, with stage IV disease or postoperative recurrence, or unresectable. Then treated with pemetrexed based chemotherapy. After two cycles of treatment, efficacy and toxicity were evaluated. Results: Pemetrexed based chemotherapy was used as second-line in 33 patients, RR(CR+PR) is 41.2%. And achieved 36.4% when used as third-line. Overall response rate of 50 patients treated with Pemetrexed based treatment was 38% (CR+PR). Treatment related side effects were bone marrow suppression, vomiting, hepatic dysfunction and malaise.No treatment related death occurred. Conclusions: Treatment with pemetrexed based chemotherapy is active and is well tolerated in patients with advanced gastric cancer.

Topology Optimization Method of Lattice Structures Based on a Genetic Algorithm

Feng Ruo-qiang,Liu Feng-cheng,Xu Wei-jia,Liu Yang 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.3

A two-stage topology optimization method of lattice structures based on a genetic algorithm is proposed. The first stage is the form-finding analysis of lattice structures, and the optimal initial shape was achieved with the numerical inverse hanging method. The second stage is the topology optimization of single-layer lattice structures, which can be realized by changing the mesh size and the tube configurations to minimize the total weight of steel tubes subject to the design requirements. The mesh configuration optimization is realized through the adjustment of the nodal horizontal co-ordinates and the removal of tubes with lower stress. The maximum displacement of the structure, the maximum stress of the circular steel tubes, and the nonlinear buckling load are the state variables, and a genetic algorithm (GA) is the optimization algorithm. Different stress-limiting values used to delete the tubes were discussed. The numerical examples show that the two-stage topology optimization method for lattice structures proposed in this paper is correct and efficient. Furthermore, the forms of the optimized structure are rich, and the structure is lightweight and efficient.

AN IDENTITY ON THE 2m-TH POWER MEAN VALUE OF THE GENERALIZED GAUSS SUMS

Liu, Feng,Yang, Quan-Hui Korean Mathematical Society 2012 대한수학회보 Vol.49 No.6

In this paper, using analytic method and the properties of the Legendre's symbol, we prove an exact calculating formula on the $2m$-th power mean value of the generalized quadratic Gauss sums for $m{\geq}2$. This solves a conjecture of He and Zhang [On the 2k-th power mean value of the generalized quadratic Gauss sums, Bull. Korean Math. Soc. 48 (2011), no. 1, 9-15].