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Lu G.-N.,South China University of Technology | Lu G.-N.,The College of New Jersey | Dang Z.,South China University of Technology | Dang Z.,Guangzhou Higher Education Mega Center | And 5 more authors.
Journal of Hazardous Materials | Year: 2010

This paper reports a theoretical validation and proposition of the reductive dechlorination pathways for polychlorinated dibenzo-p-dioxin (PCDD) congeners. Density functional theory (DFT) calculations were carried out at the B3LYP/6-31G(d) level for all PCDDs and Mulliken atomic charges on chlorine atoms were adopted as the probe of the dechlorination reaction activity. The experimentally substantiated dechlorination pathways of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TCDD) and its daughter products in the presence of zero-valent zinc were validated and the complete pathway of dechlorination of octachlorodibenzo-p-dioxin (OCDD) was proposed. The proposed pathways were found to be consistent with anaerobic biotransformation of several PCDD congeners. Four rules of thumb arrived from this study include (1) the chlorine atoms in the longitudinal (1,4,6,9) positions are removed in preference to the chlorine atoms on lateral (2,3,7,8) positions; (2) the chlorine atom that has more neighboring chlorine atoms at ortho-, meta- and para-positions is to be eliminated; (3) reductive dechlorination prefers to take place on the benzene ring having more chlorine substitutions; and (4) a chlorine atom on the side of the longitudinal symmetry axis containing more chlorine atoms is preferentially eliminated. These rules of thumb can be conveniently used for rapidly predicting the major dechlorination pathway for a given PCDD in specific systems. © 2009 Elsevier B.V.


Lu X.,Guangdong Pharmaceutical University | Lu X.,Guangzhou Higher Education Mega Center | Wang J.,Guangdong Pharmaceutical University | Wang J.,Guangzhou Higher Education Mega Center | And 4 more authors.
BMC Biotechnology | Year: 2015

Background: In our previous study, a novel liver-targeting fusion interferon (IFN-CSP) combining IFN α2b with plasmodium region I peptide was successfully constructed. IFN-CSP has significant inhibition effects on HBV-DNA replication in HepG2.2.15 cells. The aim of the present investigation was focused on how to produce high levels of recombinant IFN-CSP and its in vivo anti-hepatitis B virus (HBV) activity. Methods: A modified DNA fragment encoding IFN-CSP was synthesized according to Escherichia coli (E. coli) preferred codon usage and transformed into E. coli BL21 (DE3) for protein expression. The induction conditions were systematically examined by combining one-factor experiments with an orthogonal test (L(9)(3)(4)). The antigenicity of the purified protein was characterized by western blot analysis. The in vivo tissue distribution were assayed and compared with native IFN α2b. HBV-transgenic mice were used as in vivo model to evaluate the anti-HBV effect of the recombinant IFN-CSP. Results: The results showed that the E. coli expression system was very efficient to produce target protein. Conclusion: Our current research demonstrates for the first time that IFN-CSP gene can be expressed at high levels in E. coli through codon and expression conditions optimization. The purified recombinant IFN-CSP showed liver-targeting potentiality and anti-HBV activity in vivo. The present study further supported the application of IFN-CSP in liver-targeting anti-HBV medicines. © Lu et al.


Qian Q.,Guangzhou Higher Education Mega Center | Chen Y.,Guangzhou Higher Education Mega Center
Procedia Earth and Planetary Science | Year: 2011

Based on the data analysis of materials collected from 785 question-and-answer surveys in Guangdong, the paper obtains some main characteristic of technology innovation within SMEs and regional environment and draws some conclusions as follow: Technology innovative capacity of those SMEs in Guangdong has gained a significant improvement at the same time innovation output performance such as patent level is pool; Most of the SMEs choose cooperation strategy and simulated strategy as their enterprise technology innovative strategy; Supplied merchant and custom play an important role in innovative network, but high school, research institution and agency service institution have less role; To improve technology and administration level is the main innovative motivation for those SMEs, but lack of skilled labor force, new technology and law environment is the restricted condition of Guangdong innovative environment ; Most of the SMEs hold optimism attitude for Gguangdong province and think that Pearl river delta is their first choice for industrial investment in future. © 2011 Published by Elsevier Ltd.


Zhang H.L.,Guangzhou Higher Education Mega Center | Chen Y.H.,Guangzhou Higher Education Mega Center | Qi J.Y.,No.7West Street | Lin B.G.,No.7West Street | Fang J.D.,No.7West Street
Advanced Materials Research | Year: 2013

Take the Shenzhen Nanshan Municipal solid waste incinerator(MSWI) as the object, in total 18 ambient air samples were got. The study analyzed the distribution characteristics of ambient air heavy metals (Cu, Cd, Pb, Cr) and As in the surroundings of the MSWI. The EPA Risk Assessment Guidance for Superfund(RAGS) was used to assess the exposure risk. The results demonstrated that the Pb and Cd value in the surroundings of the MSWI were in the accept level according to the Ambient Air Quality Standards(GB3095-2012); The risk assessment showed that the carcinogenic and non-carcinogenic risks via inhalation exposure in the sorrounding of the MSWI were in the accessible levels. © (2013) Trans Tech Publications, Switzerland.


Yang F.,South China University of Technology | Yang X.,South China University of Technology | Yang X.,City University of Hong Kong | Li Z.,South China University of Technology | And 4 more authors.
Applied Microbiology and Biotechnology | Year: 2015

Thermoanaerobacterium aotearoense P8G3#4 produced β-glucosidase (BGL) intracellularly when grown in liquid culture on cellobiose. The gene bgl, encoding β-glucosidase, was cloned and sequenced. Analysis revealed that the bgl contained an open reading frame of 1314 bp encoding a protein of 446 amino acid residues, and the product belonged to the glycoside hydrolase family 1 with the canonical glycoside hydrolase family 1 (GH1) (β/α)8 TIM barrel fold. Expression of pET-bgl together with a chaperone gene cloned in vector pGro7 in Escherichia coli dramatically enhanced the crude enzyme activity to a specific activity of 256.3 U/mg wet cells, which resulted in a 9.2-fold increase of that obtained from the expression without any chaperones. The purified BGL exhibited relatively high thermostability and pH stability with its highest activity at 60 °C and pH 6.0. In addition, the activities of BGL were remarkably stimulated by the addition of 5 mM Na+ or K+. The enzyme showed strong ability to hydrolyze cellobiose with a Km and Vmax of 25.45 mM and 740.5 U/mg, respectively. The BGL was activated by glucose at concentration varying from 50 to 250 mM and tolerant to glucose inhibition with a Ki of 800 mM glucose. The supplement of the purified BGL to the sugarcane bagasse hydrolysis mixture containing a commercial cellulase resulted in about 20 % enhancement of the released reducing sugars. These properties of the purified BGL should have important practical implication in its potential applications for better industrial production of glucose or bioethanol started from lignocellulosic biomass. © 2015, Springer-Verlag Berlin Heidelberg.


Mao J.,Guangzhou Higher Education Mega Center | Mao J.,Jinan University | Li X.,Guangzhou Higher Education Mega Center | Chen W.,Guangzhou Higher Education Mega Center | And 9 more authors.
Histochemistry and Cell Biology | Year: 2012

Chloride channel-3 (ClC-3) is suggested to be a component and/or a regulator of the volume-activated Cl - channel in the plasma membrane. However, ClC-3 is predominantly located inside cells and the role of intracellular ClC-3 in tumor growth is unknown. In this study, we found that the subcellular distribution of endogenous ClC-3 varied in a cell cycle-dependent manner in HeLa cells. During interphase, ClC-3 was distributed throughout the cell and it accumulated at various positions in diVerent stages. In early G1, ClC-3 was mainly located in the nucleus. In middle G1, ClC-3 gathered around the nuclear periphery as a ring. In late G1, ClC-3 moved back into the nucleus, where it remained throughout S phase. In G2, ClC-3 was concentrated in the cytoplasm. When cells progressed from G2 to the prophase of mitosis, ClC-3 from the cytoplasm translocated into the nucleus. During metaphase and anaphase, ClC-3 was distributed throughout the cell except for around the chromosomes and was aggregated at the spindle poles and in between two chromosomes, respectively. ClC-3 was then again concentrated in the nucleus upon the progression from telophase to cytokinesis. These results reveal a cell cycle-dependent change of the subcellular distribution of ClC-3 and strongly suggest that ClC-3 has nucleocytoplasmic shuttling dynamics that may play key regulatory roles during diVerent stages of the cell cycle in tumor cells. © Springer-Verlag 2012.


Zhang M.-S.,Sun Yat Sen University | Zhang M.-S.,Guangzhou Higher Education Mega Center | Tan H.-Z.,Sun Yat Sen University | Mao J.-F.,Shanghai JiaoTong University
IEEE Transactions on Components, Packaging and Manufacturing Technology | Year: 2014

In this paper, a novel layer stack-up with free cavity resonance is proposed for high-performance power noise suppression. In this layer stack-up, power planes for power delivery are sandwiched by ground planes and are moved close to the component sides, so that they are separated from signal layers. Signal layers are isolated by ground planes, which provide ideal ground reference. Arrays of ground shorting vias are introduced to ac short ground reference plane pairs to remove their cavity resonances. This structure has free cavity resonance under the corner frequency of the periodic via array, and it has an excellent wideband noise suppression with starting point from dc. This stack-up not only has high-performance noise suppression, but also can significantly improve the signal integrity and reduce the electromagnetic interference of the board. Simulation and measurement are performed to verify the validity of the proposed layer stack-up. © 2014 IEEE.


Ou H.-S.,South China University of Technology | Wei C.-H.,South China University of Technology | Wei C.-H.,Guangzhou Higher Education Mega Center | Deng Y.,Montclair State University | And 3 more authors.
Environmental Science and Pollution Research | Year: 2014

A novel dual coagulant system of polyaluminum chloride sulfate (PACS) and polydiallyldimethylammonium chloride (PDADMAC) was used to treat natural algae-laden water from Meiliang Gulf, Lake Taihu. PACS (Aln(OH)mCl3n-m-2k(SO4)k) has a mass ratio of 10 %, a SO4 2-/Al3 + mole ratio of 0.0664, and an OH/Al mole ratio of 2. The PDADMAC ([C8H16NCl]m) has a MW which ranges from 5 × 105 to 20 × 105 Da. The variations of contaminants in water samples during treatments were estimated in the form of principal component analysis (PCA) factor scores and conventional variables (turbidity, DOC, etc.). Parallel factor analysis determined four chromophoric dissolved organic matters (CDOM) components, and PCA identified four integrated principle factors. PCA factor 1 had significant correlations with chlorophyll-a (r = 0.718), protein-like CDOM C1 (0.689), and C2 (0.756). Factor 2 correlated with UV254 (0.672), humic-like CDOM component C3 (0.716), and C4 (0.758). Factors 3 and 4 had correlations with NH3-N (0.748) and T-P (0.769), respectively. The variations of PCA factors scores revealed that PACS contributed less aluminum dissolution than PAC to obtain equivalent removal efficiency of contaminants. This might be due to the high cationic charge and pre-hydrolyzation of PACS. Compared with PACS coagulation (20 mg L-1), the removal of PCA factors 1, 2, and 4 increased 45, 33, and 12 %, respectively, in combined PACS-PDADMAC treatment (0.8 mg L-1 + 20 mg L-1). Since PAC contained more Al (0.053 g/1 g) than PACS (0.028 g/1 g), the results indicated that PACS contributed less Al dissolution into the water to obtain equivalent removal efficiency. © 2013 Springer-Verlag Berlin Heidelberg.


PubMed | Guangzhou Higher Education Mega Center
Type: | Journal: Current pharmaceutical biotechnology | Year: 2015

Interferon 2b (IFN 2b) is the first cytokine, which has been approved by FDA to treat chronic hepatitis B. However, it has no organ or tissue selectivity effect, and will be rapidly cleared out in the liver after the administration treatment. In our previous study, a novel liver-targeting fusion interferon (IFN-CSP) was constructed by recombining human IFN 2b with a CSP region I-plus peptide. The purpose of this study is to compare pharmacokinetics, tissue distribution, excretion of recombinant liver-targeting interferon IFN-CSP with IFN 2b following intramuscular administration in rats and estimate whether the fusion protein recombinant liver-targeting interferon has liver-targeting effect. Serum, tissue, urinary, fecal, and biliary concentrations of the drug were measured at various time points after administration using ELISA test. The pharmacokinetic character of IFN-CSP and IFN2b was described using a non-compartmental model after a single intramuscular administration. Our results showed that there were no significant differences between these two drugs in pharmacokinetic and elimination. However, drug concentration of recombinant liver-targeting IFN was higher than IFN 2b in the liver after intramuscular administration in rats at different time points. It was increased in the spleen but not apparently, and decreased in the heart, lung and kidney. In conclusion, compared with traditional IFN 2b, the novel recombinant liver-targeting IFN will be more accumulated in the liver tissue. With this excellent property, IFN-CSP shows a great application prospect in clinical treatment, although further investigation is still needed.


PubMed | Guangzhou Higher Education Mega Center
Type: Comparative Study | Journal: Current pharmaceutical biotechnology | Year: 2015

Interferon 2b (IFN 2b) is the first cytokine, which has been approved by FDA to treat chronic hepatitis B. However, it has no organ or tissue selectivity effect, and will be rapidly cleared out in the liver after the administration treatment. In our previous study, a novel liver-targeting fusion interferon (IFN-CSP) was constructed by recombining human IFN 2b with a CSP region I-plus peptide. The purpose of this study is to compare pharmacokinetics, tissue distribution, excretion of recombinant liver-targeting interferon IFN-CSP with IFN 2b following intramuscular administration in rats and estimate whether the fusion protein recombinant liver-targeting interferon has liver-targeting effect. Serum, tissue, urinary, fecal, and biliary concentrations of the drug were measured at various time points after administration using ELISA test. The pharmacokinetic character of IFN-CSP and IFN2b was described using a non-compartmental model after a single intramuscular administration. Our results showed that there were no significant differences between these two drugs in pharmacokinetic and elimination. However, drug concentration of recombinant liver-targeting IFN was higher than IFN 2b in the liver after intramuscular administration in rats at different time points. It was increased in the spleen but not apparently, and decreased in the heart, lung and kidney. In conclusion, compared with traditional IFN 2b, the novel recombinant liver-targeting IFN will be more accumulated in the liver tissue. With this excellent property, IFN-CSP shows a great application prospect in clinical treatment, although further investigation is still needed.

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