摘要：
To assess the aquatic ecosystem safety for silica （SiO2） nanoparticles （NPs）, the growth inhibition and photosynthetic pigment contents of Scenedesmus obliquus in logarithm growth phase exposed to SiO2 NPs and SiO2 bulk particles （BPs） suspensions were measured. SiO2 NPs with 10-20 nm diameters were found to be toxic. The 20% effective concentration （EC20） values for 72 and 96 hr were 388.1 and 216.5 mg/L, respectively. The contents of chlorophyll decreased significantly under moderate and high concentration （50, 100, and 200 mg/L） of SiO2 NPs after 96-hr exposure, but the carotenoids did not. SiO2 BPs were found to be nontoxic up to 200 mg/L. The toxicity of SiO2 NPs probablely due to their sorption to algal cells surface. The results imply that there is potential harm to aquatic environment by using SiO2 NPs, and it should deserve special concern.
关键词：
Application;Ionic liquid;Wood related industries
摘要：
The use of ionic liquids (ILs) has provided a new platform for efficient utilization of wood. In this paper, applications of ILs in wood-related industries are reviewed. First, the dissolution of wood in ILs and its application are described. Then the ILs used for wood preservation and improvement of wood anti-electrostatic and fire-proof properties are illustrated. Finally, "green" wood processing with ILs is discussed. Although some basic studies of ILs, such as their economical syntheses and toxicology are eagerly needed and some engineering problems still exist, research for application of ILs in wood-related industries has made great progress in recent years.
期刊：
Proceedings of SPIE - The International Society for Optical Engineering,2009年7519 ISSN：0277-786X
通讯作者：
Cao, Y.
作者机构：
[Ma, Hong; Bai, Jing; Cao, Yu] College of Chemistry, Central China Normal University;[Liu, Jing; Qi, Chao] College of Life Science, Central China Normal University, Wuhan 430079, China
通讯机构：
College of Chemistry, Central China Normal University, China
会议名称：
Eighth International Conference on Photonics and Imaging in Biology and Medicine (PIBM 2009)
会议时间：
Wuhan, China
会议论文集名称：
Eighth International Conference on Photonics and Imaging in Biology and Medicine (PIBM 2009)
关键词：
Antitumor;Drug delivery system (DDS);Hepatocyte- targeting;Self-assembled nano devices
摘要：
KCL-SDS assay was used to explore DNA-Protein Crosslinks (DPC) effect induced by formaldehyde (FA) and the repair. Gaseous FA could cause DPC at concentrations as 1.0 mg m−3 and 3.0 mg m−3 (p < 0.01), which was removed within 12 h. Meanwhile, in vitro studies showed that 75 µmol L−1 liquid FA could significantly induce DPC in HepG2 cells, and was removed after 18 h and 24 h. These results suggested that FA could induce DPC at relatively high concentrations, and removing of DPC in vivo required shorter time than that in vitro.
摘要：
The kinetics and mechanisms of p-nitrophenol (PNP) biodegradation by Pseudomonas aeruginosa HS-D38 were investigated. PNP could be used by HS-D38 strain as the sole carbon, nitrogen and energy source, and PNP was mineralized at the maximum concentration of 500 mg/L within 24 h in an mineral salt medium (MSM). The analytical results indicated that the biodegradation of PNP fit the first order kinetics model. The rate constant KPNP is 2.039×10~(-2) /h in MSM medium, K_(PNP+N) is 3.603×10~(-2) /h with addition of ammonium chloride and K_(PNP+C) is 9.74×10~(-3) /h with additional glucose. Addition of ammonium chloride increased the degradation of PNP. On the contrary, glucose inhibited and delayed the biodegradation of PNP. Chemical analysis results by thin-layer chromatography (TLC), UV-Vis spectroscopy and gas chromatography (GC) techniques suggested that PNP was converted to hydroquinone (HQ) and further degraded via 1,2,4-benzenetriol (1,2,4-BT) pathway.
摘要：
Pseudomonas aeruginosa strain HS-D38 was capable of mineralizing p-nitrophenol (PNP) as the sole source of carbon, nitrogen and energy. Degradation of 200 mg L−1 PNP was examined in different media including: (i) MSM (mineral salts medium, no carbon and nitrogen source); (ii) addition of 1% ammonium chloride as additional nitrogen source (ANM); and (iii) addition of 1% glucose as a carbon source (ACM). Complete degradation of 200 mg L−1 PNP was achieved in 12 h in MSM. Additional ammonium chloride accelerated the PNP degradation, but additional glucose inhibited this process. This strain metabolized as high concentration as 300 and 500 mg L−1 of PNP in 14 h and 24 h, respectively, in MSM. The degradation was accompanied by release of stoichiometric amount of nitrate from PNP. During the bacterial growth on PNP, hydroquinone and 1,2,4-benzenetriol were observed as the key degradation intermediates by using a combination of techniques, including HPLC–DAD and LC–ESI/MS compared with the authentic standards. These results indicated that PNP was degraded via a hydroquinone pathway.
作者机构：
[Du, Dan; Ye, Xiuping; Zhang, Jiande] Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.;[Liu, Deli] Cent China Normal Univ, Coll Life Sci, Wuhan 430079, Peoples R China.
通讯机构：
[Du, Dan] C;Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.
作者机构：
[Zhang, Aidong; Du, Dan; Tu, Haiyang; Ye, Xiuping; Zhang, Jiande; Zeng, Yan] Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.;[Liu, Deli] Cent China Normal Univ, Coll Life Sci, Wuhan 430079, Peoples R China.
通讯机构：
[Du, Dan] C;Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.
关键词：
zirconia nanoparticles;solid-phase extraction;square-wave voltammetry;methyl parathion;NERVE AGENTS;MULTILAYER FILMS
摘要：
A sensitive electrochemical stripping voltammetric method for analyzing organophosphate (OP) compounds was developed based on solid-phase extraction (SPE) at zirconia (ZrO2) nanoparticles modified electrode. ZrO2 nanoparticles were proved as a new sorbent for SPE of OP pesticides. Because of the strong affinity of ZrO2 for the phosphoric group, nitroaromatic OPs can strongly bind to the ZrO2 nanoparticle surface. The combination of SPE with square-wave voltammetry (SWV) provided a fast, sensitive, and selective electrochemical method for nitroaromatic OP compounds using methyl parathion (MP) as a model. The stripping response was highly linear over the MP range of 0.003-2.0 mu g/mL, with a detection limit of 0.001 mu g/mL. The fast extraction ability of ZrO2 nanoparticles makes it promising sorbent for various solid-phase extractions. (C) 2008 Elsevier B.V. All rights reserved.
摘要：
Effects of 111 days enhanced UV-B radiation on leaf pigments, grain quality, photosynthesis and growth were determined in Chinese superhigh-yield hybrid rice (Oryza sativa L.) Liangyoupeijiu (Peiai 64S × 9311). The chlorophyll concentrations of leaves under enhanced UV-B radiation were slightly reduced in the tillering stage, but recovered to levels equal to or above those of control in the later growth stages. Leaves treated with enhanced UV-B radiation for 99 days exhibited higher absorbance in the UV region than controls. Amylose concentration of UV-B treatment was significantly increased by 4.1%. Crude fat concentration, crude protein concentration and vitamin B1 showed no significant difference between control and treatment. The light-saturated photosynthetic activity of UV-B treated leaves normalized on fresh weight or chlorophyll concentration was, respectively, 45.2 and 35.3% higher than controls. Both indoor and field experiments indicated that UV-B treated leaves were more tolerant to photoinhibition, and its Do values tended to be higher than controls during the strong light period of midday. The D1 protein turnover played more important role in UV-B treated leaves against strong irradiance than in control leaves. Little difference was observed in the maximal PSII quantum efficiency of UV-B treated and control leaves during the process of leaf senescence. UV-B radiation reduced diseased grains per panicle and led to a higher seed setting rate. It may have a direct harmful effect on pathogens or reduced susceptibility of UV-B exposed plants to pathogens. Our results suggest that long-term exposure to enhanced UV-B radiation is unlikely to have detrimental effects on the photosynthetic capability of Liangyoupeijiu, and tends to inhibit its growth and biomass.
摘要：
The functional mevalonate pathway of the Class-II HMG-CoA reductase (Class-II HMGR) from bacterial pathogens is essential for the survival of these pathogens. So, Class-II HMGR has been identified as one of the most important targets of antibiotics, which could be used to treat infections caused by these pathogens. With the aim of designing novel inhibitors of Class-II HMGR, we created a theoretical model of the three-dimensional dimmer structure of Class-II HMGR from Streptococcus pneumoniae by using homology modeling and molecular dynamic simulation procedures. Subsequently, we analyzed ligand–receptor interactions by docking lovastatin and HMG into the proposed three-dimensional dimmer structure. Results revealed that the binding model of lovastatin and HMG were similar to the binding model in their crystal structure. These results further confirmed the reliability of the homology model of Class-II HMGR, and also showed that the selected parameter and method for the docking process were reasonable. In the absence of a crystal structure, our study provides an early insight into the structure and its binding to the substrate and ligand, thus providing a new starting point for the identification or rational design of more potent inhibitors.
期刊：
JOURNAL OF EXPERIMENTAL BOTANY,2007年58(12):3227-3238 ISSN：0022-0957
通讯作者：
Li, Xue-Bao
作者机构：
[Huang, Geng-Qing; Li, Li; Li, Xue-Bao; Wang, Xiu-Lan] Huazhong Normal Univ, Coll Life Sci, Wuhan 430079, Peoples R China.
通讯机构：
[Li, Xue-Bao] H;Huazhong Normal Univ, Coll Life Sci, Wuhan 430079, Peoples R China.
关键词：
Cotton;"expression profiles of GhTUA genes";"fibre elongation";fibre-specific;microtubule;"overexpression in yeast cells"
摘要：
The microtubule cytoskeleton may play an important role in the polarized growth of fibre cells that are single-cell trichomes on the surface of cotton ovules. To investigate whether the high expression levels of α-tubulin genes are correlated with fibre elongation, nine GhTUA genes (cDNAs) encoding α-tubulins with 449–451 amino acid residues were isolated and characterized in cotton. The GhTUA genes share high sequence homology at the nucleotide level (62–93% identity) in the coding region and at the amino acid level (89–99% identity), and can be classified into two subgroups. Real-time quantitative RT-PCR analysis revealed that seven out of the nine GhTUA genes are predominantly expressed in developing fibres. Among them, GhTUA9 displays the highest level of expression, revealing its fibre specificity. The GhTUA9 transcripts in fibres reached its peak value between 5–10 DPA, and dramatically declined to undetectable levels as the ovule matured further, suggesting that its expression is developmentally-regulated in fibres. The GhTUA9 gene including the promoter region was isolated from the cotton genome. To demonstrate the specificity of the GhTUA9 promoter, the 5′-flanking region, including the promoter and 5′-untranslated region, was fused with the GUS gene. Histochemical assays demonstrated that the GhTUA9:GUS gene was specifically expressed in elongating fibres. Overexpression of GhTUA9 in fission yeast (Schizosaccharomyces pombe) promoted atypical longitudinal growth of the host cells by 1.4–1.7-fold, indicating that the GhTUA9 gene is involved in cell elongation. Given all the above results, it is proposed that the GhTUA9 gene may play an important role in fibre elongation.
