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      • KCI등재

        Statistical Optimization of Culture Media and Conditions for Production of Mannan by Saccharomyces cerevisiae

        Hong-Zhi Liu,Qiang Wang,Yuan-Yuan Liu,Fang Fang 한국생물공학회 2009 Biotechnology and Bioprocess Engineering Vol.14 No.5

        In view of the increase in Saccharomyces cerevisiae mannan content, the culture medium and condition for S.cerevisiae were optimized in this study. The influence of culture medium ingredients such as carbon and nitrogen sources, inorganic ion, and enzyme activator on mannan production were evaluated using factional design. The mathematical model was established by the quadratic rotary combination design through response surface analysis. The optimized concentrations of culture medium were determined as follows: 4.98 g/100 mL, sucrose; 4.39 g/100 mL, soybean peptone; 3.10 g/100 mL, yeast extract; and 2.21 g/100 mL, glycerol. The optimized culture medium increased mannan production from 82.7 ± 3.4 mg/100 mL to 162.53 ± 3.47 mg/100 mL. The influence of original pH, inoculum size, temperature, and media volume on mannan production was evaluated and confirmed by orthogonale experimental design, with the order of effect as follows: media volume > temperature > initial pH > inoculation size. The optimized culture condition was pH, 5; inoculum size, 5 ml; temperature, 32oC; and media volume, 40 mL. The maximum mannan production increased to 258.5 ± 9.1 mg/100 mL at the optimum culture condition.=It was evident that the mannan production was affected significantly by culture medium and condition optimization (é < 0.01). In view of the increase in Saccharomyces cerevisiae mannan content, the culture medium and condition for S.cerevisiae were optimized in this study. The influence of culture medium ingredients such as carbon and nitrogen sources, inorganic ion, and enzyme activator on mannan production were evaluated using factional design. The mathematical model was established by the quadratic rotary combination design through response surface analysis. The optimized concentrations of culture medium were determined as follows: 4.98 g/100 mL, sucrose; 4.39 g/100 mL, soybean peptone; 3.10 g/100 mL, yeast extract; and 2.21 g/100 mL, glycerol. The optimized culture medium increased mannan production from 82.7 ± 3.4 mg/100 mL to 162.53 ± 3.47 mg/100 mL. The influence of original pH, inoculum size, temperature, and media volume on mannan production was evaluated and confirmed by orthogonale experimental design, with the order of effect as follows: media volume > temperature > initial pH > inoculation size. The optimized culture condition was pH, 5; inoculum size, 5 ml; temperature, 32oC; and media volume, 40 mL. The maximum mannan production increased to 258.5 ± 9.1 mg/100 mL at the optimum culture condition.=It was evident that the mannan production was affected significantly by culture medium and condition optimization (é < 0.01).

      • KCI등재

        Myopericytoma Involving the Parotid Gland as Depicted on Multidetector CT

        Zhi-Gang Chu,Jian-Qun Yu,Zhi-Gang Yang,Zhi-Yu Zhu,Hong-Mei Yuan 대한영상의학회 2009 Korean Journal of Radiology Vol.10 No.4

        Myopericytoma is a newly proposed subgroup of perivascular tumors in the World Health Organization classification of soft tissue tumors. In this study, we report a case of a benign myopericytoma with detailed multidetector CT (MDCT) findings in the parotid gland, a location that has not been described for this type of tumor previously. The clinical presentation, imaging features, histopathological and immunohistochemical findings, and the differential diagnosis with other tumors in the parotid gland are described and reviewed.

      • KCI등재

        Transcriptome analysis of rice leaves in response to Rhizoctonia solani infection and reveals a novel regulatory mechanism

        De Peng Yuan,Xiao Feng Xu,Hong Woo-Jong,Si Ting Wang,Xin Tong Jia,Yang Liu,Shuang Li,Zhi Min Li,Qian Sun,Qiong Mei,Shuai Li,정기홍,Song Hong Wei,Yuan Hu Xuan 한국식물생명공학회 2020 Plant biotechnology reports Vol.14 No.5

        Sheath blight disease (ShB) severely afects rice production; however, the details of defense against ShB remain unclear. To understand the rice defense mechanism against ShB, an RNA sequencing analysis was performed using Rhizoctonia solani inoculated rice leaves after 48 h of inoculation. Among them, 3417 genes were upregulated and 2532 were downregulated when compared with the control group (>twofold or<1/2). In addition, the diferentially expressed genes were classifed via Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and MapMan analyses. Fifty-nine GO terms and seven KEGG pathways were signifcantly enriched. A MapMan analysis demonstrated that the phytohormone and metabolic pathways were signifcantly altered. Interestingly, the expression levels of 359 transcription factors, including WRKY, MYB, and NAC family members, as well as 239 transporter genes, including ABC, MFS, and SWEET, were signifcantly changed in response to R. solani AG1-IA inoculation. Additionally, OsWRKY53 and OsAKT1 negatively regulate the defense response in rice against R. solani via gain of function study for OsWRKY53 and loss of function study for OsAKT1, respectively. Furthermore, several diferentially expressed genes contain R. solani-responsive cis acting regulatory elements in their promoter regions. Taken together, our analyses provide valuable information for the additional study of the defense mechanisms against ShB, and the candidate genes identifed in this study will be useful resource for future breeding to enhance resistance against ShB.

      • SCIESCOPUSKCI등재

        In vitro Arsanilic Acid Induction of Apoptosis in Rat Hepatocytes

        Yuan, Hui,Gong, Zhi,Yuan, li-Yun,Han, Bo,Han, Hong-Ryul Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.9

        This paper aimed to study the toxicity of arsanilic acid on rat primary hepatocytes in vitro by a modification of the perfusion method. The conditions included concentrations of 0, 1.085, 10.85, 108.5, 1,085 and 10,850 mg/kg arsanilic acid in RPMI 1,640 medium at rat hepatocytes plates respectively, each group had five repeats at $37^{\circ}C$ for 48 h. The rat primary hepatocytes survival ratio, DNA Ladder, activities of glutathione peroxidase (GSH-px), superoxide dismutase (SOD) and catalase (CAT) in hepatocytes, activity of SOD in the medium and the expression of gene bax in hepatocytes were measured at 12 h, 24 h and 48 h respectively. The results showed that arsanilic acid decreased the activities of GSH-px and SOD, and increased the activity of CAT in all dosages, and affected as positive DNA ladder. Although the SOD activities of both hepatocytes and medium in 1.085 mg/L arsanilic acid were significantly lower than the base line at 12 h, CAT activity in 10.85 mg/L arsanilic acid was significantly higher than the base line at 48 h, and all of the DNA ladders were positive, which means 1.085 mg/L arsanilic acid induced apoptosis at 24 h. The gene expression of bax was significantly upregulated in 1.085 mg/L arsanilic acid or higher for 24 h.The parameters in 1,085 mg/L and 10,850 mg/L arsanilic acid had more severe changes than the others at any time indicating that these levels of arsanilic acid were toxic hazards for hepatocyte survival. It was concluded that arsanilic acid induced a dosage- and time-dependent gene expression of bax, 1.085 mg/L arsanilic acid could be involved in rat liver cell apoptosis at 24 h. Arsanilic acid as additives in livestock feed could present potential toxic implications for farm animals.

      • KCI등재

        Diversity of Arbuscular Mycorrhizal Fungi Associated with a Sb Accumulator Plant, Ramie (Boehmeria nivea), in an Active Sb Mining

        ( Yuan Wei ),( Zhi Peng Chen ),( Feng Chang Wu ),( Ji Ning Li ),( Yu Xian Shangguan ),( Fa Sheng Li ),( Qing Ru Zeng ),( Hong Hou ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.8

        Arbuscular mycorrhizal fungi (AMF) have great potential for assisting heavy metal hyperaccumulators in the remediation of contaminated soils. However, little information is available about the symbiosis of AMF associated with an antimony (Sb) accumulator plant under natural conditions. Therefore, the objective of this study was to investigate the colonization and molecular diversity of AMF associated with the Sb accumulator ramie (Boehmeria nivea) growing in Sb-contaminated soils. Four Sb mine spoils and one adjacent reference area were selected from Xikuangshan in southern China. PCR-DGGE was used to analyze the AMF community composition in ramie roots. Morphological identification was also used to analyze the species in the rhizosphere soil of ramie. Results obtained showed that mycorrhizal symbiosis was established successfully even in the most heavily polluted sites. From the unpolluted site Ref to the highest polluted site T4, the spore numbers and AMF diversity increased at first and then decreased. Colonization increased consistently with the increasing Sb concentrations in the soil. A total of 14 species were identified by morphological analysis. From the total number of species, 4 (29%) belonged to Glomus, 2 (14%) belonged to Acaulospora, 2 (14%) belonged to Funneliformis, 1 (7%) belonged to Claroideoglomus, 1 (7%) belonged to Gigaspora, 1 (7%) belonged to Paraglomus, 1 (7%) belonging to Rhizophagus, 1 (7%) belonging to Sclervocystis, and 1 (7%) belonged to Scutellospora. Some AMF sequences were present even in the most polluted site. Morphological identification and phylogenetic analysis both revealed that most species were affiliated with Glomus, suggesting that Glomus was the dominant genus in this AMF community. This study demonstrated that ramie associated with AMF may have great potential for remediation of Sb-contaminated soils.

      • KCI등재

        Enzymatic Synthesis of Theanine with Escherichia coli γ-glutamyltranspeptidase from a Series of γ-glutamyl Anilide Substrate Analogues

        Hong-juan Zhang,Wei-guo Zhang,Zhi-yuan Wang,Yue-ping Zhan,Li-sheng Xu,Jun-zhong Liu,Qian Liu,Qing-cai Jiao 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.2

        In order to investigate the catalytic mechanism of Escherichia coli γ-glutamyltranspeptidase, ten para- and meta- substituted γ-glutamyl anilides were chemically prepared and employed as substrates to synthesize L-theanine to assay the activity of γ-glutamyltranspeptidase. The reaction was optimized for γ-glutamyl-p-nitroanilide. Key factors such as substrate specificity, pH, temperature, and the substrate mole ratio were all investigated. Kinetic studies of the acyl transfer reaction were described and the Hammett plot was constructed. This study indicated that the ratelimiting acylation reaction of γ-glutamyltranspeptidase can apparently be accelerated by either the electron-withdrawing or electron-donating substituents of γ-glutamyl anilides. The reaction could be catalyzed by the general acid and carboxy of Asp-433 or phenolic hydroxyl Tyr-444 may be the acid by autodock simulation for all prepared γ-glutamyl anilides.

      • KCI등재

        Sparse Channel Estimation of Single Carrier Frequency Division Multiple Access Based on Compressive Sensing

        ( Yuan Hong Zhong ),( Zhi Yong Huang ),( Bin Zhu ),( Hua Wu ) 한국정보처리학회 2015 Journal of information processing systems Vol.11 No.3

        It is widely accepted that single carrier frequency division multiple access (SC-FDMA) is an excellent candidate for broadband wireless systems. Channel estimation is one of the key challenges in SC-FDMA, since accurate channel estimation can significantly improve equalization at the receiver and, consequently, enhance the communication performances. In this paper, we study the application of compressive sensing for sparse channel estimation in a SC-FDMA system. By skillfully designing pilots, their patterns, and taking advantages of the sparsity of the channel impulse response, the proposed system realizes channel estimation at a low cost. Simulation results show that it can achieve significantly improved performance in a frequency selective fading sparse channel with fewer pilots.

      • KCI등재

        Tolfenamic Acid Suppresses Inflammatory Stimuli-Mediated Activation of NF-κB Signaling

        ( Hong Jun Shao ),( Zhi Yuan Lou ),( Jin Boo Jeong ),( Kui Jin Kim ),( Ji Hye Lee ),( Seong Ho Lee ) 한국응용약물학회 2015 Biomolecules & Therapeutics(구 응용약물학회지) Vol.23 No.1

        Tolfenamic acid (TA) is a traditional non-steroid anti-inflammatory drug (NSAID) and has been broadly used for the treatment of migraines. Nuclear factor kappa B (NF-κB) is a sequence-specific transcription factor and plays a key role in the development and progression of inflammation and cancer. We performed the current study to investigate the underlying mechanisms by which TA suppresses inflammation focusing on NF-κB pathway in TNF-α stimulated human normal and cancer cell lines and lipopolysaccharide (LPS)-stimulated mouse macrophages. Different types of human cells (HCT116, HT-29 and HEK293) and mouse macrophages (RAW264.7) were pre-treated with different concentrations of TA and then exposed to inflammatory stimuli such as TNF-α and LPS. Transcriptional activity of NF-κB, IκB-α-degradation, p65 translocation and mitogen-activated protein kinase (MAPK) activations were measured using luciferase assay and Western blots. Pre-treatment of TA repressed TNF-α- or LPS-stimulated NF-κB transactivation in a dose-dependent manner. TA treatment reduced degradation of IκB-α and subsequent translocation of p65 into nucleus. TA significantly down-regulated the phosphorylation of c-Jun N-terminal kinase (JNK). However, TA had no effect on NF-κB signaling and JNK phosphorylation in HT-29 human colorectal cancer cells. TA possesses anti-inflammatory activities through suppression of JNK/NF-κB pathway in different types of cells.

      • KCI등재

        Ginsenoside Re Increases Fertile and Asthenozoospermic Infertile Human Sperm Motility by Induction of Nitric Oxide Synthase

        Hong Zhang,Qing-Ming Zhou,Xiao-Da Li,Yi Xie,Xin Duan,Feng-Ling Min,Bing Liu,Zhi-Gang Yuan 대한약학회 2006 Archives of Pharmacal Research Vol.29 No.2

        We investigated the effects of Ginsenoside Re on human sperm motility in fertile and asthenozoospermic infertile individuals in vitro and the mechanism by which the Ginsenosides play their roles. The semen samples were obtained from 10 fertile volunteers and 10 asthenozoospermic infertile patients. Spermatozoa were separated by Percoll and incubated with 0, 1, 10 or 100 µM of Ginsenoside Re. Total sperm motility and progressive motility were measured by computer-aided sperm analyzer (CASA). Nitric oxide synthase (NOS) activity was determined by the 3H-arginine to 3H-citrulline conversion assay, and the NOS protein was examined by the Western blot analysis. The production of sperm nitric oxide (NO) was detected using the Griess reaction. The results showed that Ginsenoside Re significantly enhanced both fertile and infertile sperm motility, NOS activity and NO production in a concentration-dependent manner. Sodium nitroprusside (SNP, 100 nM), a NO donor, mimicked the effects of Ginsenoside Re. And pretreatment with a NOS inhibitor Nω-Nitro-L-arginine methyl ester (L-NAME, 100 µM) or a NO scavenger N-Acetyl-L-cysteine (LNAC, 1 mM) completely blocked the effects of Ginsenoside Re. Data suggested that Ginsenoside Re is beneficial to sperm motility, and that induction of NOS to increase NO production may be involved in this benefit.

      • Hypermethylation and Clinicopathological Significance of RASAL1 Gene in Gastric Cancer

        Chen, Hong,Pan, Ying,Cheng, Zheng-Yuan,Wang, Zhi,Liu, Yang,Zhao, Zhu-Jiang,Fan, Hong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

        Background: Recent studies have suggested that expression of the RAS protein activator like-1 gene (RASAL1) is decreased in gastric carcinoma tissues and cell lines, indicated a role in tumorigenesis and development of gastric cancer. Reduced expression of RASAL1 could result in aberrant increase of activity of RAS signaling pathways in cancer cells. However, the exact mechanism which induces down-regulation of the RASAL1 gene remains unclear. This study aimed to determine the methylation status and regulation of RASAL1 in gastric cancer. Materials and Methods: Using the methylation-specific polymerase chain reaction (MSP), the methylation status of CpG islands in the RASAL1 promoter in gastric cancers and paired adjacent non-cancerous tissues from 40 patients was assessed and its clinicopathological significance was analyzed. The methylation status of RASAL1 in gastric cancer lines MKN-28, SGC-790l, BGC-823, as well as in normal gastric epithelial cell line GES-l was also determined after treatment with a DNA methyltransferase inhibitor, 5-aza-2'-doexycytidine (5-Aza-CdR). RAS activity (GAS-GTP) was assessed through a pull-down method, while protein levels of ERK1/2, a downstream molecule of RAS signaling pathways, were determined by Western blotting. Results: The frequencies of RASAL1 promoter methylation in gastric cancer and paired adjacent non-cancerous tissues were 70% (28/40) and 30% (12/40) respectively (P<0.05). There were significantly correlations between RASAL1 promoter methylation with tumor differentiation, tumor size, invasive depth and lymph node metastasis in patients with gastric cancer (all P<0.05), but no correlation was found for age or gender. Promoter hypermethylation of the RASAL1 gene was detected in MKN-28, SGC-790l and BGC-823 cancer cells, but not in the normal gastric epithelial cell line GES-1. Elevated expression of the RASAL1 protein, a decreased RAS-GTP and p-ERK1/2 protein were detected in three gastric cancer cell lines after treatment with 5-Aza-CdR. Conclusions: Aberrant hypermethylation of the RASAL1 gene promoter frequently occurs in gastric cancer tissues and cells. In addition, the demethylating agent 5-Aza-CdR can reverse the hypermethylation of RASAL1 gene and up-regulate the expression of RASAL1 significantly in gastric cancer cells in vivo. Our study suggests that RASAL1 promoter methylation may have a certain relationship with the reduced RASAL1 expression in gastric cancer.

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