Photodegradation of formaldehyde by activated carbon loading TiO2 synthesized via microwave irradiation

Fei Tian,Zhansheng Wu,Yujun Yan,Xinyu Ge,Yanbin Tong 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.7

A microwave-assisted synthetic method to form a series of AC/TiO2 for application as photocatalytic degradation of formaldehyde (HCHO) is presented. The influence of prepared conditions such as microwave power, microwave time, and the ratio of activated carbon and titanium dioxide sol (AC/TiO2-sel) on the degradation of HCHO was investigated. HCHO conversion of 58.68% was achieved by AC/TiO2 at microwave power of 700W for 15 min with AC/TiO2-sel ratio of 1 : 2, which maintained multiple properties including high content of anatase and TiO2 largely distributed on AC without reunion, and possessed abundant functional groups for degradation. The influence of operation parameters on the degradation was also investigated: increasing dosage of catalyst and decreasing the initial concentration of HCHO could increase the conversion of HCHO. Acidic conditions can promote degradation effect. Stronger intensity of UV irradiating could improve efficiency of photocatalytic conversion of HCHO.

Dual Effect of Hepatic Macrophages on Liver Ischemia and Reperfusion Injury during Liver Transplantation

Tian-Fei Lu,Tai-Hua Yang,Cheng-Peng Zhong,Chuan Shen,Wei-Wei Lin,Guang-Xiang Gu,Qiang Xia,Ning Xu 대한면역학회 2018 Immune Network Vol.18 No.3

Ischemia-reperfusion injury (IRI) is a major complication in liver transplantation (LT) and it is closely related to the recovery of grafts' function. Researches has verified that both innate and adaptive immune system are involved in the development of IRI and Kupffer cell (KC), the resident macrophages in the liver, play a pivotal role both in triggering and sustaining the sterile inflammation. Damage-associated molecular patterns (DAMPs), released by the initial dead cell because of the ischemia insult, firstly activate the KC through pattern recognition receptors (PRRs) such as toll-like receptors. Activated KCs is the dominant players in the IRI as it can secret various pro-inflammatory cytokines to exacerbate the injury and recruit other types of immune cells from the circulation. On the other hand, KCs can also serve in a contrary way to ameliorate IRI by upregulating the anti-inflammatory factors. Moreover, new standpoint has been put forward that KCs and macrophages from the circulation may function in different way to influence the inflammation. Managements towards KCs are expected to be the effective way to improve the IRI.

Comparison of the Antifungal and Antiaflatoxigenic Potential of Liquid and Vapor Phase of Thymus vulgaris Essential Oil Against Aspergillus flavus

TIAN, FEI,LEE, SANG YOO,CHUN, HYANG SOOK ational Association for Food Protection 2019 Journal of food protection Vol.82 No.12

<B>ABSTRACT</B><P>The antifungal and antiaflatoxigenic activity of Thymus vulgaris essential oil (EO) against Aspergillus flavus was evaluated over a range of concentrations in vapor- and liquid-phase contact tests. Total reduction in mycelial growth in the vapor- and liquid-phase tests was detected at EO concentrations of 20 and 400 μg/mL, respectively. Treatment with 10 μg/mL EO reduced aflatoxin production by 97.0 and 56.4% in the vapor- and liquid-phase tests, respectively. Greater inhibition of the expression of both fungal development-related genes (brlA, abaA, and wetA) and aflatoxin biosynthesis-related genes (aflR, aflD, and aflK) was also observed in the vapor-phase test. A substantial reduction in aflatoxin production was also observed in brown rice (72.7%) and white rice (18.0%). Our results indicate that the way this EO contacts fungal cells significantly affects its antifungal activity and that T. vulgaris EO in vapor phase might be a good strategy to control fungal contamination.</P><B>HIGHLIGHTS</B>

p-Cymene and its derivatives exhibit antiaflatoxigenic activities against Aspergillus flavus through multiple modes of action

Fei Tian,우소영,이상유,전향숙 한국응용생명화학회 2018 Applied Biological Chemistry (Appl Biol Chem) Vol.61 No.5

Three monoterpenes, 1-methyl-4-(1-methylethyl)- benzene, and its derivatives, carvacrol and thymol, were tested for their antifungal and antiaflatoxigenic activities against Aspergillus flavus, and their potential in vitro mechanisms were evaluated. The monoterpenes significantly inhibited mycelial growth, spore production, and aflatoxin production in a dose-dependent manner. Furthermore, their antifungal effects were related to the suppression of fungal development regulatory genes (brlA, abaA, and wetA) and inhibition of ergosterol synthesis. Additionally, the down-regulation of the relative expression of genes related to aflatoxin biosynthesis (aflD, aflK, aflQ, and aflR) revealed an antiaflatoxigenic mechanism of the monoterpenes. These observations suggest that the three monoterpenes exhibit antiaflatoxigenic activities through multiple modes of action and may be useful for controlling aflatoxin contamination in food.

Retrospective Evaluation of Discrepancies between Radiological and Pathological Size of Hepatocellular Carcinoma Masses

Tian, Fei,Wu, Jian-Xiong,Rong, Wei-Qi,Wang, Li-Ming,Wu, Fan,Yu, Wei-Bo,An, Song-Lin,Liu, Fa-Qiang,Feng, Li,Liu, Yun-He Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Background: The size of a hepatic neoplasm is critical for staging, prognosis and selection of appropriate treatment. Our study aimed to compare the radiological size of solid hepatocellular carcinoma (HCC) masses on magnetic resonance imaging (MRI) with the pathological size in a Chinese population, and to elucidate discrepancies. Materials and Methods: A total of 178 consecutive patients diagnosed with HCC who underwent curative hepatic resection after enhanced MRI between July 2010 and October 2013 were retrospectively identified and analyzed. Pathological data of the whole removed tumors wereassessed and differences between radiological and pathological tumor size were identified. All patients were restaged using a modified Tumor-Node-Metastasis (TNM) staging system postoperatively according to the maximum diameter alteration. The lesions were classified as hypo-staged, iso-staged or hyper-staged for qualitative assessment. In the quantitative analysis, the relative pre and postoperative tumor size contrast ratio ($%{\Delta}size$) was also computed according to size intervals. In addition, the relationship between radiological and pathological tumor diameter variation and histologic grade was analyzed. Results: Pathological examination showed 85 (47.8%) patients were overestimated, 82 (46.1%) patients underestimated, while accurate measurement by MRI was found in 11 (6.2%) patients. Among the total subjects, 14 (7.9%) patients were hypo-staged and 15 (8.4%) were hyper-staged post-operatively. Accuracy of MRI for calculation and characterized staging was related to the lesion size, ranging from 83.1% to 87.4% (<2cm to ${\geq}5cm$, p=0.328) and from 62.5% to 89.1% (cT1 to cT4, p=0.006), respectively. Overall, MRI misjudged pathological size by 6.0 mm (p=0.588 ), and the greatest difference was observed in tumors <2cm (3.6 mm, $%{\Delta}size=16.9%$, p=0.028). No statistically significant difference was observed for moderately differentiated HCC (5.5mm, p=0.781). However, for well differentiated and poorly differentiated cases, radiographic tumor maximum diameter was significantly larger than the pathological maximum diameter by 3.15 mm and underestimated by 4.51 mm, respectively (p=0.034 and 0.020). Conclusions: A preoperative HCC tumor size measurement using MRI can provide relatively acceptable accuracy but may give rise to discrepancy in tumors in a certain size range or histologic grade. In pathological well differentiated subjects, the pathological tumor size was significantly overestimated, but underestimated in poorly differentiated HCC. The difference between radiological and pathological tumor size was greatest for tumors <2 cm. For some HCC patients, the size difference may have implications for the decision of resection, transplantation, ablation, or arterially directed therapy, and should be considered in staging or selecting the appropriate treatment tactics.

MiR-34b/c rs4938723 Polymorphism Significantly Decreases the Risk of Digestive Tract Cancer: Meta-analysis

Ji, Tian-Xing,Zhi, Cheng,Guo, Xue-Guang,Zhou, Qiang,Wang, Guo-Qiang,Chen, Bo,Ma, Fei-Fei Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.14

Background: Previous studies investigating the association between miR-34b/c rs4938723 polymorphism and cancer risk showed inconclusive. Here, we performed meta-analysis to investigate the association between miR- 34b/c rs4938723 polymorphism and digestive cancer risk. Materials and Methods: Literature database including PubMed, OVID, Chinese National Knowledge Infrastructure (CNKI) were searched for publications concerning the association between the miR-34b/c rs4938723 polymorphism and digestive cancer risk. Results: A total of 6 studies consisting of 3246 cases and 3568 controls were included in this meta-analysis. The combined analysis suggested the miR-34b/c rs4938723 polymorphism significantly reduced digestive cancer risk under allelic model, homogeneous co-dominant model and recessive model (C vs T: OR=0.88, 95%CI=0.82-0.95, p-value=0.001; CC vs TT: OR =0.67, 95%CI=0.57-0.80, p-value=0.000; CC vs TT/TC: OR=0.68, 95%CI=0.58-0.80, p-value=0.000). Q-test and I2 test revealed no significant heterogeneity in all genotype comparisons. The Begger's funnel plot and Egger's test did not show significant publication bias. Conclusions: The current evidence supports the conclusion that the miR-34b/c rs4938723 polymorphism decreases an individual's susceptibility to digestive cancers.

Robust Stabilization of a Class of Uncertain Fractional-order Chaotic Systems via a Novel Sliding Mode Control Scheme

Xiaomin Tian,Shumin Fei,Lin Chai 보안공학연구지원센터 2014 International Journal of Hybrid Information Techno Vol.7 No.6

This paper proposes a novel sliding mode control (SMC) scheme to stabilize a class of fractional-order chaotic systems. Through constructing two sliding mode variables, the control problem of n-dimensional system can be transformed to the equivalent stabilizing problem of a reduced-order system. Subsequently, on the basis of second-order sliding mode (SOSM) technique, a robust control law is designed, which strongly attenuates the chattering phenomenon inherent in traditional sliding mode controller, and guarantees the existence of sliding motion in a finite time. The stability of two sliding mode variables to the origin is proved by conventional and fractional Lyapunov theories, respectively. Finally, two numerical examples are provided to illustrate the effectiveness of the proposed approach.

Active Compounds from Schisandra chinensis Exhibiting Tyrosinase Activity and Melanin Content Inhibition in B16 Melanoma Cells

Zheng-Fei Yan,Jian Guo,Feng-Hua Tian,Xin-Xin Mao,Yu Li,Chang-Tian Li 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.4

Schisandra chinensis has been used as traditional medicine. The structures of isolate active compounds (schisandrin B, deoxyschisandrin, schisandrin C) from S. chinensis were characterized by physical and spectroscopic analyses. Active compounds were tested for their potential to act as anti-melanogenesis or skin-whitening agents by their abilities to inhibit tyrosinase activity in the cell-free mushroom tyrosinase assay and cellular tyrosinase derived from B16 melanoma cells. The tyrosinase inhibitory activity was correlated to the inhibition of melanin productions in α-MSH-stimulated and unstimulated B16 cells. Cellular tyrosinase kinetics were analyzed and showed by Lineweaver- Burk plot. Schisandrin B was minimally cytotoxic (cell viability: 88.99% at 0.75 μM) and the IC50 value for suppression of mushroom tyrosinase activity was estimated as 0.6 μM. Zymography analysis demonstrated schisandrin B’s concentration-dependent effects and the kinetic analysis indicated schisandrin B’s noncompetitive-inhibitory action.

Molecular Characteristics and Extracellular Expression Analysis of Farnesyl Pyrophosphate Synthetase Gene in Inonotus obliquus

Zheng-Fei Yan,Pei Lin,Feng-Hua Tian,국무창,이태후,Chang-Tian Li 한국생물공학회 2016 Biotechnology and Bioprocess Engineering Vol.21 No.4

A farnesyl pyrophosphate synthase gene was cloned from Inonotus obliquus, designated IOFPS. The IOFPS cDNA contained an open reading frame (ORF) of 972 bps, encoding a protein of 324 amino acids. The deduced amino acid sequence of IOFPS revealed moderate homology with that of other fungi, and contained four conserved domains. Phylogenetic analysis showed that IOFPS belonged to the basidiomycete group. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis indicated that the IOFPS gene was successfully expressed in a yeast recombinant cell. Enzyme catalytic experiments were carried out with purified protein (IOFPS protein), which was isolated and purified from recombinant yeast cells. The special hydrolysis product (farnesol) was then detected by liquid chromatography coupled with tandem mass spectrometry (LC-MS). These results indicated that the cloned cDNA encoded a farnesyl diphosphate synthase and the IOFPS protein maintained catalytic activity in vitro.

Four-Leg Object Recognition for Service Robot Based on Top-hat Transformation

Hao Wu,Guohui Tian,Xinran Wang,Fei Lu 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.12

A method of object recognition for objects with special topological structure is developed based on top-hat transformation for service robot. The objects with four legs are easily detected and recognized by service robot with laser ranger array by this method. First, the top-hat transformation in one dimension is reviewed, then the recognition strategy of self-adapting threshold for objects with special topological structure is proposed, and the general data process for object recognition and position is proposed and analyzed. Experimental results show that the process of object recognition based on top-hat transformation proposed in this article is an effective and accurate application.