Click Synthesis of Hydrogels by Metal-Free 1,3-Dipolar Cycloaddition Reaction Between Maleimide and Azide Functionalized Polymers

Hong-Zheng Zhu,Gang Wang,Hong-Liang Wei,Hui-Juan Chu,Jing Zhu 한국고분자학회 2016 Macromolecular Research Vol.24 No.9

Herein, a metal-free 1,3-dipolar cycloaddition click reaction was used to prepare hydrogels. First, copolymer of N,N-dimethylacrylamide and 2-hydroxyethyl methacrylate was synthesized via free radical copolymerization with an initiator of 2,2'-azobisisobutyronitrile and a solution of 1,4-dioxane. Second, maleimide-functionalized polymer was obtained by a coupling reaction of the above synthesized copolymer and N-maleoyl alanine with a dehydrating agent of N,N'-dicyclohexylcarbodiimide. Similarly, azido-modified polymer was prepared by the reaction between azidoacetic acid and the as-prepared copolymer. Third, the hydrogels were obtained by the reaction of the azidomodified polymer and maleimide-functionalized copolymer without any initiator or catalyst. Gelation times of different conditions were measured by a cuvette inversion method. The samples of different steps were analysized by means of FTIR, NMR, SEM, etc. The swelling behaviour of the gels was investigated via a general gravimetric method. Finally, release mechanism was explored with a model drug molecule of 5-fluorouracil. It was found temperature, concentration and solvent had an impact on the gelation time. And the swelling behavior and drug-controlled release profiles of the hydrogels were relevant to the concentration of polymers used for the hydrogels.

The Design of Fingerprint Identification System based on Improved Binarization Algorithm

Zhu Heng-jun,Guo Ying,Zhang nan-nan,Liang Hong 보안공학연구지원센터 2014 International Journal of Security and Its Applicat Vol.8 No.6

MiR-454 Prompts Cell Proliferation of Human Colorectal Cancer Cells by Repressing CYLD Expression

Liang, Hong-Liang,Hu, Ai-Ping,Li, Sen-Lin,Xie, Jia-Ping,Ma, Qing-Zhu,Liu, Ji-Yong Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Previous studies have shown that miR-454 plays an important role in a variety of biological processes in various human cancer cells. However, the underlying mechanisms of this microRNA in colorectal cancer (CRC) cells remain largely unknown. In the present study, we investigated the miR-454 role in CRC cell proliferation. We found that miR-454 expression is markedly upregulated in CRC tissues and CRC cells compared with the matched tumor adjacent tissues and the FHC normal colonic cell line. Ectopic expression of miR-454 promoted the proliferation and anchorage-independent growth of CRC cells, whereas inhibition of miR-454 reduced this effect. Bioinformatics analysis further revealed cylindromatosis (CYLD), a putative tumor suppressor as a potential target of miR-454. Data from luciferase reporter assays showed that miR-454 directly binds to the 3'-untranslated region (3'-UTR) of CYLD mRNA and repressed expression at both transcriptional and translational levels. In functional assays, CYLD-silenced in miR-454-in-transfected SW480 cells have positive effect to promote cell proliferation, suggesting that direct CYLD downregulation is required for miR-454-induced CRC cell proliferation. In sum, our data provide compelling evidence that miR-454 functions as an onco-miRNA, playing a crucial role in the promoting cell proliferation in CRC, and its oncogenic effect is mediated chiefly through direct suppression of CYLD expression.

Enhancement of Virus-induced Gene Silencing in Tomato by Low Temperature and Low Humidity

Da-Qi Fu,Ben-Zhong Zhu,Hong-Liang Zhu,Hong-Xing Zhang,Yuan-Hong Xie,Wei-Bo Jiang,Xiao-Dan Zhao,Yun-Bo Luo 한국분자세포생물학회 2006 Molecules and cells Vol.21 No.1

Virus-induced gene silencing (VIGS) is an attractive reverse-genetics tool for studying gene function in plants. We showed that silencing of a phytoene desaturase (PDS) gene is maintained throughout TRV-PDSinoculated tomato plants as well as in their flowers and fruit and is enhanced by low temperature (15°C) and low humidity (30%). RT-PCR analysis of the PDS gene revealed a dramatic reduction in the level of PDS mRNA in leaves, flowers and fruits. Silencing of PDS results in the accumulation of phytoene, the desaturase substrate. In addition, the content of chlorophyll a, chlorophyll b and total chlorophyll in the leaves of PDS-silenced plants was reduced by more than 90%. We also silenced the LeEIN2 gene by infecting seedlings, and this suppressed fruit ripenning. We conclude that this VIGS approach should facilitate large-scale functional analysis of genes involved in the development and ripening of tomato.

The Experimental Practices of VoIP Based on the Commercial Softswitch Device

Liang Xin-tao,Zhu Hong-yuan,Wang Dun-ci 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.5

A softswitch is the central device of the next-generation network (NGN) which is the hotspot in telecommunication industry. So it’s of great significance for the students and related companies to carry out practical experiments and researches based on the commercial softswitch device. Three stage targets of the VoIP, from the elementary to the profound, are proposed according to the characters of the softswitch teaching. The hardware and the software queuing system of the NGN laboratory of Harbin University of Science and Technology, which was designed and built for the targets, are introduced. Students can be queued for experiments with commercial VoIP devices in the NGN laboratory. Three categories of experiments, IP to IP, IP to Phone, and Softphone application development, are designed to cultivate innovative talents.

Potential Biomarker of L-type Amino Acid Transporter 1 in Breast Cancer Progression

Liang, Zhongxing,Cho, Heidi T.,Williams, Larry,Zhu, Aizhi,Liang, Ke,Huang, Ke,Wu, Hui,Jiang, Chunsu,Hong, Samuel,Crowe, Ronald,Goodman, Mark M.,Shim, Hyun-Suk The Korea Society of Nuclear Medicine 2011 핵의학 분자영상 Vol.45 No.2

Purpose L-type amino acid transporter 1 (LAT1) is essential for the transport of large neutral amino acids. However, its role in breast cancer growth remains largely unknown. The purpose of the study is to investigate whether LAT1 is a potential biomarker for the diagnosis and treatment of breast cancer. Methods LAT1 mRNA and protein levels in breast cancer cell lines and tissues were analyzed. In addition, the effects of targeting LAT1 for the inhibition of breast cancer cell tumorigenesis were assessed with soft agar assay. The imaging of xenograft with anti-1-amino-3-[$^{18}F$]fluorocyclobutane-1-carboxylic acid (anti-[$^{18}F$]FACBC) PET was assessed for its diagnostic biomarker potential. Results Normal breast tissue or low malignant cell lines expressed low levels of LAT1 mRNA and protein, while highly malignant cancer cell lines and high-grade breast cancer tissue expressed high levels of LAT1. In addition, higher expression levels of LAT1 in breast cancer tissues were consistent with advanced-stage breast cancer. Furthermore, the blockade of LAT1 with its inhibitor, 2-aminobicyclo[ 2.2.1]heptane-2-carboxylic acid (BCH), or the knockdown of LAT1 with siRNA, inhibited proliferation and tumorigenesis of breast cancer cells. A leucine analog, anti-[$^{18}F$]FACBC, has been demonstrated to be an excellent PET tracer for the non-invasive imaging of malignant breast cancer using an orthotopic animal model. Conclusions The overexpression of LAT1 is required for the progression of breast cancer. LAT1 represents a potential biomarker for therapy and diagnosis of breast cancer. Anti-[$^{18}F$]FACBC that correlates with LAT1 function is a potential PET tracer for malignant breast tumor imaging.

Preparation of Thermosensitive Hydrogels by means of Tandem Physical and Chemical Crosslinking

Hong-Liang Wei,Kai Yao,Zhe Yang,Hui-Juan Chu,Jing Zhu,Cun-Cai Ma,Zi-Xuan Zhao 한국고분자학회 2011 Macromolecular Research Vol.19 No.3

The tandem physical and chemical crosslinking was used to prepare injectable hydrogels. First, the terpolymers with diene groups were synthesized by the free radical copolymerization of N-isopropylacrylamide (NIPA), N,N-dimethylacrylamide (DMA) and furfuryl methacrylate (FM). Second, dienophile-functionalized terpolymers were obtained from the terpolymers of NIPA, DMA, and 2-hydroxyethyl methacrylate (HEMA) and Nmaleoyl alanine (AMI) by a coupling reaction under N,N'-dicyclohexylcarbodiimide (DCC). When the screened diene-functionalized terpolymer and dienophile-functionalized terpolymer were dissolved separately in water and mixed, physically cross-linked hydrogels formed rapidly within 10 s at 37 ℃. Subsequently, the physically crosslinked hydrogels could change gradually into chemically cross-linked hydrogels by a Diels-Alder reaction and the mechanical strength of the hydrogels could be improved. The swelling behavior study suggests that the hydrogels possess thermosensitivity and good reproducibility at different temperatures. The strategy described, i.e. incorporating the advantages of physically crosslinked hydrogels and chemically crosslinked hydrogels, has potential applications in the preparation of injectable hydrogels.

Constructing all-in-one graphene-based supercapacitors for electrochemical energy storage via interface integration strategy

Zhu Yucan,Peng Long,Chen Song,Feng Yuchao,Xia Jianxing,Wang Wei,Chen Liang,Yin Hong,Zhou Minjie,Hou Zhaohui 한국탄소학회 2023 Carbon Letters Vol.33 No.3

With the rapid development of flexible wearable electronic products, flexible all graphene-based supercapacitors (FGSCs) with reduced graphene oxide rGO//graphene oxide (GO)//rGO structure have attracted substantial attention due to their unique structures and energy storage mechanism. However, restricted by design idea and preparation technology, improvement of capacitance performance for the FGSCs is not obvious recently. Herein, we demonstrate that an interface integration strategy of constructing the high-performance FGSCs with compact structure. Hydroquinone (HQ)-modified rGO (HQ-rGO) films (electrode materials) and sulfuric acid-intercalated GO films (electrolyte/separator) are assembled into the FGSCs utilizing hydrogen bonding and capillary contractility. The HQ further improves the electrochemical capacitance of electrode materials. The synergistic effect of the hydrogen bonding and capillary contractility guarantees compact and stable structure of the device. The resulting FGSCs exhibit an excellent areal capacitance of 804.6 mF cm−2 (@2 mA cm−2) and 441 mF cm−2 (@30 mA cm−2), and their highest energy and power densities can achieve 109.5 μWh cm−2 and 21,060 μW cm−2, respectively. These performances are superior to other all-in-one graphene-based SCs reported. Therefore, the construction technology of the FGSCs is a promising for developing all graphene-based SCs with high-performance.

MicroRNA-576-3p Inhibits Proliferation in Bladder Cancer Cells by Targeting Cyclin D1

Liang, Zhen,Li, Shiqi,Xu, Xin,Xu, Xianglai,Wang, Xiao,Wu, Jian,Zhu, Yi,Hu, Zhenghui,Lin, Yiwei,Mao, Yeqing,Chen, Hong,Luo, Jindan,Liu, Ben,Zheng, Xiangyi,Xie, Liping Korean Society for Molecular and Cellular Biology 2015 Molecules and cells Vol.38 No.2

MicroRNAs (miRNAs) are small, endogenous RNAs that play important gene-regulatory roles by binding to the imperfectly complementary sequences at the 3'-UTR of mRNAs and directing their gene expression. Here, we first discovered that miR-576-3p was down-regulated in human bladder cancer cell lines compared with the non-malignant cell line. To better characterize the role of miR-576-3p in bladder cancer cells, we over-expressed or down-regulated miR-576-3p in bladder cancer cells by transfecting with chemically synthesized mimic or inhibitor. The overexpression of miR-576-3p remarkably inhibited cell proliferation via G1-phase arrest, and decreased both mRNA and protein levels of cyclin D1 which played a key role in G1/S phase transition. The knock-down of miR-576-3p significantly promoted the proliferation of bladder cancer cells by accelerating the progression of cell cycle and increased the expression of cyclin D1. Moreover, the dual-luciferase reporter assays indicated that miR-576-3p could directly target cyclin D1 through binding its 3'-UTR. All the results demonstrated that miR-576-3p might be a novel suppressor of bladder cancer cell proliferation through targeting cyclin D1.

Isocoumarin Derivatives from the Sea Squirt-derived Fungus Penicillium stoloniferum QY2-10 and the Halotolerant Fungus Penicillium notatum B-52

Zhi-Hong Xin,Li-Tian,Tian-jiao Zhu,Wen-Liang Wang,Lin Du,Yu-chun Fang,Qian-Qun Gu,Wei-Ming Zhu 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.7

Two isocoumarin derivatives, stoloniferol A (1) and B (2), a known 5α, 8α-epidioxy-23-methyl- (22E, 24R)-ergosta-6, 22-dien-3β-ol (3), and a known dihydrocitrinone (4) were isolated from the ethyl acetate extract of the sea squirt-derived fungus, Penicillium stoloniferum QY2-10, and a halophilic fungus, Penicillium notatum B-52, respectively. Their structures were elucidated by spectroscopic methods and optical rotation. The stereochemistry of 2 was determined on the basis of different NOE experiments and chemical transformation. Compound 3 showed cytotoxicity against P388 cells, with an IC50 value of 4.07 µM.