A novel inverse opal zirconia pigment with controllable color saturation

Li-li Wang,Xin-xin Liu,Xiao-peng Li,Xiu-feng Wang,Li-na Feng,Xu-ri Hou 한양대학교 세라믹연구소 2021 Journal of Ceramic Processing Research Vol.22 No.2

The inverse opal zirconia pigments were prepared by template method using polystyrene microspheres with the size of 340 ± 10nm as raw material and the in situ carbon was formed to achieve controllable and adjustable color saturation by sintering atvarious temperatures in nitrogen atmosphere with various nitrogen flow rates. The effects of nitrogen atmosphere, nitrogenflow rate and sintering temperature on the morphology, phase and color saturation of the inverse opal zirconia wereinvestigated. The results showed that when the inverse opal zirconia was sintered at 450 oC to 600 oC in nitrogen atmosphere,the green color saturation could be adjusted by changing the nitrogen flow rate from 0.2 L/min to 0.8 L/min. When thenitrogen rate was 0.8L/min, the green color saturation of the inverse opal zirconia could be adjusted by changing the sinteringtemperature from 450 oC to 600 oC. It indicated that the more the amount of in-situ carbon was generated, the more stray lightwas absorbed and the higher green color saturation of the inverse opal zirconia could be obtained. Further increasing thesintering temperature to 700 oC would destroy the inverse opal morphology of zirconia and affect the carbonization of theorganic component.

A novel M2e-multiple antigenic peptide providing heterologous protection in mice

Feng Wen,Ji-Hong Ma,Hai Yu,Fu-Ru Yang,Meng Huang,Yan-Jun Zhou,Ze-Jun Li,Xiu-Hui Wang,Guo-Xin Li,Yi-Feng Jiang,Wu Tong,Guangzhi Tong 대한수의학회 2016 Journal of Veterinary Science Vol.17 No.1

Swine influenza viruses (SwIVs) cause considerable morbidity and mortality in domestic pigs, resulting in a significant economic burden. Moreover, pigs have been considered to be a possible mixing vessel in which novel strains loom. Here, we developed and evaluated a novel M2e-multiple antigenic peptide (M2e-MAP) as a supplemental antigen for inactivated H3N2 vaccine to provide cross-protection against two main subtypes of SwIVs, H1N1 and H3N2. The novel tetra-branched MAP was constructed by fusing four copies of M2e to one copy of foreign T helper cell epitopes. A high-yield reassortant H3N2 virus was generated by plasmid based reverse genetics. The efficacy of the novel H3N2 inactivated vaccines with or without M2e-MAP supplementation was evaluated in a mouse model. M2e-MAP conjugated vaccine induced strong antibody responses in mice. Complete protection against the heterologous swine H1N1 virus was observed in mice vaccinated with M2e-MAP combined vaccine. Moreover, this novel peptide confers protection against lethal challenge of A/Puerto Rico/8/34 (H1N1). Taken together, our results suggest the combined immunization of reassortant inactivated H3N2 vaccine and the novel M2e-MAP provided cross-protection against swine and human viruses and may serve as a promising approach for influenza vaccine development.

Synthesis of rod-like titanium doped hydroxyapatite nanopowder

Li-li Wang,Xiu-feng Wang,Cheng-long Yu,Yan-qi Zhao 한양대학교 세라믹연구소 2013 Journal of Ceramic Processing Research Vol.14 No.6

Rod-like titanium doped hydroxyapatite (Ti-doped HA) nanopowder was synthesized using Ca(NO3)2 • 4H2O, (NH4)2HPO4 and tetraethylorthotitanate as precursor materials via a combination of chemical co-precipitation and microwave techniques route. The effect of the content of titanium in Ti-doped HA (0.2-2.4 wt.%) on sintering behavior, crystal size, shape and morphology was investigated. The results suggested that the addition of titanium to HA structure did restrain HA decomposition and thermal reaction between HA and titanium, which resulted in improved thermal stability of HA at high sintering temperature. The grain size of sintered Ti-doped HA, which was much smaller than that of pure HA. 0.8 wt.% addition of titanium to HA, was optimum for producing nanometer-sized rod-like Ti-doped HA crystal with improved thermal stability.

Preparation of nanorod hydroxyapatite by combination of chemical precipitation and microwave technique

Li-li Wang,Xiu-feng Wang,Hong-tao JIANG 한양대학교 세라믹연구소 2015 Journal of Ceramic Processing Research Vol.16 No.4

Nanorod hydroxyapatite powders were synthesized using H3PO4 and Ca(OH)2 as precursor materials via a combination of chemical precipitation and microwave techniques route. Effects of various reactive solvent, heating mode of microwave and microwave time on phase stability and morphology of as-prepared hydroxyapatite were investigated based on orthogonal design. The results suggested that when the reactive solvent was pure water, uniform, no agglomerated rod-like hydroxyapatite was formed. Increasing microwave time improved the crystallinity and morphology of rod-like hydroxyapatite, significantly. Heating mode of microwave had a profound influence on the shape, dispersibility and morphology of nanorod hydroxyapatite. Continuously heating by microwave was better for synthesis of nanorod hydroxyapatite. Phase stability of high energy metastable hydroxyapatite brought by microwave route was improved by low temperature presintering.

The SARS Crisis and the Prospect of Chinese Government Reform

( Xiu Feng Li ) 서울대학교 한국행정연구소 2003 Journal of Policy Studies Vol.18 No.1

Increased Serotonin Signaling Contributes to the Warburg Effect in Pancreatic Tumor Cells Under Metabolic Stress and Promotes Growth of Pancreatic Tumors in Mice

Jiang, Shu-Heng,Li, Jun,Dong, Fang-Yuan,Yang, Jian-Yu,Liu, De-Jun,Yang, Xiao-Mei,Wang, Ya-Hui,Yang, Min-Wei,Fu, Xue-Liang,Zhang, Xiao-Xin,Li, Qing,Pang, Xiu-Feng,Huo, Yan-Miao,Li, Jiao,Zhang, Jun-Feng Elsevier 2017 Gastroenterology Vol.153 No.1

<P><B>Background & Aims</B></P> <P>Desmoplasia and poor vascularity cause severe metabolic stress in pancreatic ductal adenocarcinomas (PDACs). Serotonin (5-HT) is a neuromodulator with neurotransmitter and neuroendocrine functions that contributes to tumorigenesis. We investigated the role of 5-HT signaling in the growth of pancreatic tumors.</P> <P><B>Methods</B></P> <P>We measured the levels of proteins that regulate 5-HT synthesis, packaging, and degradation in pancreata from Kras<SUP>G12D/+</SUP>/Trp53<SUP>R172H/+</SUP>/Pdx1-Cre (KPC) mice, which develop pancreatic tumors, as well as in PDAC cell lines and a tissue microarray containing 81 human PDAC samples. We also analyzed expression levels of proteins involved in 5-HT synthesis and degradation by immunohistochemical analysis of a tissue microarray containing 311 PDAC specimens, and associated expression levels with patient survival times. 5-HT level in 14 matched PDAC tumor and non-tumor tissues were analyzed by ELISA. PDAC cell lines were incubated with 5-HT and cell survival and apoptosis were measured. We analyzed expression of the 5-HT receptor HTR2B in PDAC cells and effects of receptor agonists and antagonists, as well as HTR2B knockdown with small hairpin RNAs. We determined the effects of 5-HT stimulation on gene expression profiles of BxPC-3 cells. Regulation of glycolysis by 5-HT signaling via HTR2B was assessed by immunofluorescence and immunoprecipitation analyses, as well as by determination of the extracellular acid ratio, glucose consumption, and lactate production. Primary PDACs, with or without exposure to SB204741 (a selective antagonist of HTR2B), were grown as xenograft tumors in mice, and SB204741 was administered to tumor-bearing KPC mice; tumor growth and metabolism were measured by imaging analyses.</P> <P><B>Results</B></P> <P>In immunohistochemical analysis of a tissue microarray of PDAC specimens, increased levels of TPH1 and decreased level of MAOA, which regulate 5-HT synthesis and degradation, correlated with stage and size of PDACs and shorter patient survival time. We found levels of 5-HT to be increased in human PDAC tissues compared with non-tumor pancreatic tissues, and PDAC cell lines compared with non-transformed pancreatic cells. Incubation of PDAC cell lines with 5-HT increased proliferation and prevented apoptosis. Agonists of HTR2B, but not other 5-HT receptors, promoted proliferation and prevented apoptosis of PDAC cells. Knockdown of HTR2B in PDAC cells, or incubation of cells with HTR2B inhibitors, reduced their growth as xenograft tumors in mice. We observed a correlation between 5-HT and glycolytic flux in PDAC cells; levels of metabolic enzymes involved in glycolysis, the phosphate pentose pathway, and hexosamine biosynthesis pathway increased significantly in PDAC cells following 5-HT stimulation. 5-HT stimulation led to formation of the HTR2B–LYN–p85 complex, which increased PI3K–Akt–mTOR signaling and the Warburg effect by increasing protein levels of MYC and HIF1A. Administration of SB204741 to KPC mice slowed growth and metabolism of established pancreatic tumors and prolonged survival of the mice.</P> <P><B>Conclusions</B></P> <P>Human PDACs have increased levels of 5-HT, and PDAC cells increase expression of its receptor, HTR2B. These increases allow for tumor glycolysis under metabolic stress and promote growth of pancreatic tumors and PDAC xenograft tumors in mice.</P>

Alu Tandem Sequences Inhibit GFP Gene Expression by Triggering Chromatin Wrapping

Xiu Fang Wang,Xiao Yan Wang,Jing Liu,Jing Jing Feng,Wen Li Mu,Xiao Juan Shi,Qin Qing Yang,Xiao Cui Duan,Ying Xie,Zhan Jun Lu 한국유전학회 2009 Genes & Genomics Vol.31 No.3

Alu elements belonging to the short interspersed nuclear elements (SINE) of repetitive elements are present in more than one million copies which altogether represent 10% of the whole human genome. In this study, the roles of Alu tandem sequences in the process of GFP gene (GFP) expression and packing into chromatin of its DNA were studied. To detect the effect of Alu repeats on gene expression, different copies of Alus were inserted GFP downstream respectively in pEGFP-C1 vector. We found that Alu sequences decreased the amount of GFP transcription, the percentage of GFP positive cells and the accessibility to DNase I in length-dependent manner. Inserting Alu caused the production of higher-molecular-mass RNA, indicating Alu sequence did not induce premature transcriptional termination. Tight packing chromatins keep silent and resist to DNase I digestion, which is a general phenomenon. We suggested that head and tail tandem Alu sequences suppressed GFP expression in length dependent manner by triggering chromatin packing.

Hyperin Extracted from Manchurian Rhododendron Leaf Induces Apoptosis in Human Endometrial Cancer Cells Through a Mitochondrial Pathway

Li, Fu-Rong,Yu, Feng-Xiu,Yao, Shu-Tong,Si, Yan-Hong,Zhang, Wei,Gao, Lin-Lin Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Background: A number of effective prevention measures have been introduced in attempts to substantially reduce both the incidence and mortality due to many kinds of cancer. The search for new anti-cancer compounds in foods or in plant medicines is one realistic and promising approach to prevention. Chinese medicines provide a rich pool of novel and efficacious agents for cancer prevention and treatment. Previously it was demonstratrated that hyperin extracted from the Manchurian rhododendron leaf reduces the proliferation of many cancer cells. The present study was carried out to evaluate its effects on human endometrial cancer cell viability and apoptosis and to investigate its mechanisms of action in RL952 cells. Methods: Cell viability was measured using the MTT assay. Intracellular calcium ions were detected using laser-scanning confocal microscopy. The effects of hyperin on apoptosis related proteins in RL952 cells were examined using Western blot analysis. Results: The growth of RL952 cells was inhibited by treatment with hyperin. OD values of caspase-3 and caspase-9 were increased and expression of bcl-2 was increased and bax was decreased in protein levels in RL952 cells after 24 h of hyperin treatment, Moreover, intracellular calcium accumulation occurred in hyperin-treated cells. Conclusion: These results suggest that hyperin may play an important role in tumor growth suppression by inducing apoptosis in human endometrial cells via a $Ca^{2+}$-related mitochondrion apoptotic pathway in RL952 cells.

Genome of Betaproteobacterium Caenimonas sp. Strain SL110 Contains a Coenzyme F420 Biosynthesis Gene Cluster

( Xiu Ling Li ),( Fu Ying Feng ),( Yong Hui Zeng ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.11

To probe the genomic properties of microbes thriving in desert lakes, we sequenced the full genome of a betaproteobacterial strain (SL110) belonging to the understudied genus Caenimonas of the family Comamonadaceae. This strain was isolated from a freshwater lake in the western Gobi Desert, Northern China. Its genome contains genes encoding carbon monoxide dehydrogenase, nitrate reductase, nitrite reductase, nitric oxide reductase, and sulfur oxidation enzymes, highlighting the potentially important contribution of this group of bacteria to the cycling of inorganic elements in nature. Unexpectedly, a coenzyme F420 biosynthesis gene cluster was identified. A further search for F420 biosynthesis gene homologs in genomic databases suggests the possible widespread presence of F420 biosynthesis gene clusters in proteobacterial genomes.

Purification and Characterization of Cathepsin B from the Gut of the Sea Cucumber (Stichopus japonicas)

Li-Ming Sun,Bei-Wei Zhu,Hai-tao Wu,Lei Yu,Da-Yong Zhou,Xiuping Dong,Jing-Feng Yang,Dong-Mei Li,Wen-Xiu Ye,Yoshiyuki Murata 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.4

Cathepsin B from the gut of sea cucumber (Stichopus japonicas) was purified 81-fold with a 3%recovery by ammonium sulfate fractionation and a series chromatography on DEAE Sepharose CL-6B, Sephadex G-75, and TSK-Gel 3000 SWxl. The purified protein appeared as a single band on Native-PAGE but showed 2bands of 23 and 26 kDa on SDS-PAGE. The optimum activity was found at pH 5.5 and 45°C. The enzyme was stable at pH 4.5-6.0 and the thermal stability was up to 50oC. The enzyme was strongly inhibited by E-64, iodoacetic acid, and antipain, demonstrating it is a cysteine protease containing sulfhydryl groups. Cu^2+, Ni^2+, and Zn^2+ could strongly inhibit the enzyme activity. The amino acid sequences of the purified enzyme were acquired by mass spectrometer, which did not show any homology with previously described cathepsins, suggesting it may be a novel member.