Effects of Reaction Parameters on Self-degradation of L-ascorbic Acid and Self-degradation Kinetics

Ya Li,Yan Yang,Ai-Nong Yu,Kui Wang 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.1

The degradation behavior of L-ascorbic acid (ASA) was investigated under different parameters of temperature, time, and pH. Higher temperatures and longer times accelerated the ASA degradation. Degradation product distributions changed with different pH values. As solution pH of 4.5 was beneficial for formation of uncolored intermediate products with an absorbance maximum at 294 nm. Formation of brown products was promoted at pH values from 5.8 to 6.8 with an absorbance maximum at 420 nm. Under different pH conditions, volatile products formation varied. Furfural and derivatives of furan were primary products due to the effects of pH. The non-enzymatic selfdegradation behavior of ASA was characteristic of first-order kinetics based on a classic dynamic model. Activation energy values varied under different pH values. An ASA degradation mechanism and pathway are proposed.

Preparation and High Degradation Activity of Supported Nano-Bi2WO6-TiO2/Nickel Foam Photocatalyst

Qin Tong,Ya-Mei Dong,Xiao-Jia Wang,Peng Yan,Dan-Nong He 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.6

The supported nano-Bi2WO6–TiO2/nickel foam photocatalyst was synthesized via spraying method with silica sol as a binder. The as-prepared photocatalyst with large surface and thermal stability exhibited enhanced photocatalytic performance for degradation of Rhodamine B (RhB) solution in sunlight irradiation. The results showed that the RhB solution could be degraded to 71.6% within 60 min, exhibiting that improved photocatalytic activity increased by 77.6%, compared with that of pure Bi2WO6–TiO2 nanoparticles. Its high photocatalytic activity was due to the presence of nickel foam in the catalytic process, making the Bi2WO6–TiO2 highly dispersed and increasing the contact area of the photocatalysts with the organic pollutants. At the same time, a possible photocatalytic mechanism for the enhanced photocatalytic performance was investigated.

Screening of Anti-Biofilm Compounds from Marine-Derived Fungi and the Effects of Secalonic Acid D on Staphylococcus aureus Biofilm

( Jie Wang ),( Xu-hua Nong ),( Xiao-yong Zhang ),( Xin-ya Xu ),( Muhammad Amin ),( Shu-hua Qi ) 한국미생물생명공학회(구 한국산업미생물학회) 2017 Journal of microbiology and biotechnology Vol.27 No.6

Biofilm formation of Staphylococcus aureus is one of its mechanisms of drug resistance. Antibiofilm screening of 106 compounds from marine-derived fungi displayed that 12 compounds inhibited S. aureus biofilm formation by >50% at the concentration of 100 μg/ml, and only secalonic acid D (SAD) and B inhibited by >90% at 6.25 μg/ml without inhibiting cell growth after 24-h incubation. Meanwhile, it was found that the double bond between C-1 and C-10 of citrinin derivatives and the C-C connection position of two chromone monomers may be important for their anti-biofilm activities. Moreover, SAD slightly facilitated biofilm eradication and influenced its architecture. Furthermore, SAD slowed the cell growth rate in the preceding 18-h incubation and differentially regulated transcriptional expression of several genes, such as agr, isaA, icaA, and icaD, associated with biofilm formation in planktonic and biofilm cells, which may be the reason for the anti-biofilm activity of SAD. Finally, SAD acted synergistically against S. aureus growth and biofilm formation with other antibiotics. These findings indicated that various natural products from marine-derived fungi, such as SAD, could be used as a potential biofilm inhibitor against S. aureus.

MiR-374b Promotes Proliferation and Inhibits Apoptosis of Human GIST Cells by Inhibiting PTEN through Activation of the PI3K/Akt Pathway

Long, Zi-Wen,Wu, Jiang-Hong,Hong, Cai,Wang, Ya-Nong,Zhou, Ye Korean Society for Molecular and Cellular Biology 2018 Molecules and cells Vol.41 No.6

Gastrointestinal stromal tumours (GIST) are the most common mesenchymal tumors of the gastrointestinal (GI) tract. In order to investigate a new treatment fot GIST, we hypothesized the effect of miR-374b targeting PTEN gene-mediated PI3K/Akt signal transduction pathway on proliferation and apoptosis of human gastrointestinal stromal tumor (GIST) cells. We obtained GIST tissues and adjacent normal tissues from 143 patients with GIST to measure the levels of miR-374b, PTEN, PI3K, Akt, caspase9, Bax, MMP2, MMP9, ki67, PCNA, P53 and cyclinD1. Finally, cell viability, cell cycle and apoptosis were detected. According to the KFGG analysis of DEGs, PTEN was involved in a variety of signaling pathways and miRs were associated with cancer development. The results showed that MiR-374b was highly expressed, while PTEN was downregulated in the GIST tissues. The levels of miR-374b, PI3K, AKT and PTEN were related to tumor diameter and pathological stage. Additionally, miR-374b increased the mRNA and protein levels of PI3K, Akt, MMP2, MMP9, P53 and cyclinD1, suggesting that miR-374b activates PI3K/Akt signaling pathway in GIST-T1 cells. Moreover, MiR374b promoted cell viability, migration, invasion, and cell cycle entry, and inhibited apoptosis in GIST cells. Taken together, the results indicated that miR-374b promotes viability and inhibits apoptosis of human GIST cells by targeting PTEN gene through the PI3K/Akt signaling pathway. Thus, this study provides a new potential target for GIST treatment.

MiR-374b Promotes Proliferation and Inhibits Apoptosis of Human GIST Cells by Inhibiting PTEN through Activation of the PI3K/Akt Pathway

Zi-Wen Long,Jiang-Hong Wu,Cai-Hong,Ya-Nong Wang,Ye Zhou 한국분자세포생물학회 2018 Molecules and cells Vol.41 No.6

Gastrointestinal stromal tumours (GIST) are the most common mesenchymal tumors of the gastrointestinal (GI) tract. In order to investigate a new treatment fot GIST, we hypothesized the effect of miR-374b targeting PTEN gene-mediated PI3K/Akt signal transduction pathway on proliferation and apoptosis of human gastrointestinal stromal tumor (GIST) cells. We obtained GIST tissues and adjacent normal tissues from 143 patients with GIST to measure the levels of miR-374b, PTEN, PI3K, Akt, caspase9, Bax, MMP2, MMP9, ki67, PCNA, P53 and cyclinD1. Finally, cell viability, cell cycle and apoptosis were detected. According to the KFGG analysis of DEGs, PTEN was involved in a variety of signaling pathways and miRs were associated with cancer development. The results showed that MiR-374b was highly expressed, while PTEN was downregulated in the GIST tissues. The levels of miR-374b, PI3K, AKT and PTEN were related to tumor diameter and pathological stage. Additionally, miR-374b increased the mRNA and protein levels of PI3K, Akt, MMP2, MMP9, P53 and cyclinD1, suggesting that miR-374b activates PI3K/Akt signaling pathway in GIST-T1 cells. Moreover, MiR-374b promoted cell viability, migration, invasion, and cell cycle entry, and inhibited apoptosis in GIST cells. Taken together, the results indicated that miR-374b pro-motes viability and inhibits apoptosis of human GIST cells by targeting PTEN gene through the PI3K/Akt signaling pathway. Thus, this study provides a new potential target for GIST treatment.

Three-Port Laparoscopic Exploration is not Sufficient for Patients with T4 Gastric Cancer

Huang, Hua,Jin, Jie-Jie,Long, Zi-Wen,Wang, Wei,Cai, Hong,Liu, Xiao-Wen,Yu, Hong-Mei,Zhang, Li-Wen,Wang, Ya-Nong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

Gastric cancer continues to be a leading cause of cancer death. The majority of patients with gastric adenocarcinoma in China present with advanced disease. Ruling out unresectable cancers from an unnecessary "open" exploration is very important. The aim of this study was to assess the value of five-port anatomical laparoscopic exploration in T4 gastric cancer in comparison with three-port laparoscopic exploration and laparotomy exploration. We conducted a retrospective study on 126 patients with T4 stage scheduled for D2 curative gastrectomy based on computed tomography (CT) staging at Department of Gastric Cancer and Soft Tissue Sarcoma, Fudan University Shanghai Cancer Center, from Apr. 2011 to Apr. 2013. Laparotomy exploration (Group I), three-port laparoscopic exploration (Group II) or five-port anatomical laparoscopic exploration (Group III) were performed prior to radical gastrectomy. Accuracy rate for feasibility of D2 curative gastrectomy in laparotomy exploration and five-port anatomical laparoscopic exploration groups was higher than that in the three-port laparoscopic exploration group. Five-port anatomical laparoscopic exploration group had the highest accuracy resection rate (Group I vs Group II vs Group III,92.6% vs78.6% vs 97.7%; p<0.05) and shorter length of hospitalization (Group I vs Group II vs Group III, $9.58{\pm}4.17$ vs $6.13{\pm}2.85$ vs $5.00{\pm}1.81$; p<0.001). Three-port laparoscopic exploration has low accuracy rate for assessing feasibility of D2 curative gastrectomy and five-port anatomical laparoscopic exploration should be performed on patients with T4 gastric cancer.