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Stochastic bi-resonance induced by external noise for Ca^2. signaling in hepatocytes

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Science china Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1,2.HOU Zhonghuai1 & XIN Houwen1 1.Department of chemical Physics,univer.ity of Science and Technology of {2.,Hefei 2.002.,{2. 2.college of Physics and Electronic Information,Anhui Normal univer.ity,Wuhu 2.1000,{2. Department of chemical Physics University of Science and Technology of China Hefei China college of Physics and Electronic Information Anhui Normal University Wuhu China

The influence of external noise on intracellular Ca2. oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2. oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2.3,5) Jian GAO~2.Xiao-mei LAN~3 Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~32.Department of Pharmacology,School of chemical Biology & Pharmaceutical Sciences,Capital univer.ity of Medical Sciences,Beijing 100069,{2. 3 Institute of Cardiovascular Science at Health Science Center,Peking univer.ity Beijing 100083,{2. 4 Institute of Molecular Medicine and college of Life Science,Peking univer.ity,Beijing 100871,{2. Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China

Aim:Intracellular Ca2.plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3Rs）in the media-tion of cardiac intracellular Ca2.and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3Rsmay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2.sparkoccurrence and global Ca2.***,we hypothesized that Ca2.releasethrough IP3Rs was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3BM）,a membrane-permeant ester of IP3,to activate IP3Rs directly,and Fluo 4/AM tomeasure intracellular Ca2.***:IP3BM(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2.spark release（especially in the perinuclear area）and global Ca2.*** importantly,IP3R inhibitors,2.aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3BM-induced Ca2.responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3H]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3R signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2.sparks α1 adrenergic stimulation cardiac hypertrophy

Orthogonal design for optimization of pigment extraction from surface sediments of the Changjiang River Estuary

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Acta Oceanologica Sinica 2011年第4期30卷 33-42页

作者： ZHAO Jun YAO Peng YU Zhigang Thomas S Bianchi Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao 266100 China Department of Oceanography Texas A ＆ M University College Station TX 77843 USA Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao 266100 China Institute of Marine Organic Geochemistry College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

Using a suitable solvent for extracting pigments from sediment for high performance liquid chromatography（HPLC） analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass,as well as community composition. Five methodological factors（sample dehydration,extraction solvent,extraction duration,number of extractions,and ratio of solvent volume：sample weight） were studied using an L 9（3 4 ） orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary（LDE）,using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L 9（3 4 ） orthogonal design experiments and showed that the extraction solvent was the most important,with extraction duration the second most important,and numbers of extraction and ratio of solvent volume：sample weight was the least important. The mixed solvent treatment comprised of acetone,methanol and water（80：15：5,by volume） was best for polar pigment extraction,with 100% acetone better for apolar pigments. For most pigments employed in this study（i.e.,peridinin,fucoxanthin,alloxanthin,diatoxanthin,zeaxanthin,pheophytin-a and β-carotene） ,3 h was found to be enough time for extraction from these deltaic sediments. However,for chlorophyll-a,the most important pigment used for estimating algal biomass,12.h was needed. A small amount of solvent（3 ml） with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately,no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study,taking into consideration the properties of sediments and pigments in question.

关键词： sedimentary pigments extraction orthogonal design HPLC Changjiang River Estuary

One approach to calculating the solvent reorganization energy of intramolecular electron transfer

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Chinese Science Bulletin 2003年第1期48卷 35-38页

作者： FU Kexiang1,2. LI Xiangyuan1, ZHU Quan1 & LU Shenzhuang1 1. college of chemical Engineering, Sichuan {2., Chengdu 610065, china 2. college of Physics, Sichuan {2., Chengdu 610064, china Correspondence should be addressed to Li Xiangyuan (e-mail: xyli@***) college of chemical Engineering Sichuan University Chengdu 610065 China college of Physics Sichuan University Chengdu 610064 China

On the basis of the electromagnetic field theory and the spherical cavity approximation, the expressions ofGibbs free energies under equilibrium and non-equilibrium solvation conditions are obtained by solving the electrostatic potential equations with boundary conditions. The surface charges produced by the orientational polarization of equi-librium solvation are taken fixed in the case of non-equilibrium situation, for the slow-response of the orientational polarization to electron transfer of the solvent molecules. Anew expression of solvent reorganization energy has beenobtained and this method is applied to the electron transfer systems, NO+/NO, NO2./NO2. and NO2./NO. The solvent reorganization energies have been evaluated.

关键词：分子内电子传递溶剂重排能定向极化自由能电子极化计算方法

Detection of Prorocentrum donghaiense using sandwich hybridization integrated with nuclease protection assay

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Acta Oceanologica Sinica 2009年第2期28卷 121-126页

作者： CHEN Jie ZHEN Yu MI Tiezhu YU Zhigang college of Marine Life Science Ocean University of China Qingdao 266003 China college of Environmental Science and Engineering Ocean University of China Qingdao 266100 China college of Chemistry and chemical Engineering Ocean University of China Qingdao 266100 China

Prorocentrum donghaiense is an important harmful algae bloom （HAB） causing creature in china＇s seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay （NPA-SH） was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, and the regression equation is y=4× 10^- 6x＋ 0.694 9, in which x is the cell number, and y is the optical density, with r2.0.953 5. These results show that the NPA-SH method has good feasibility in the detection of P. donghaiense. Results of NPA-SH and microscopy are excellent for each sample. The NPA-SH method was a simple way in quantitative detection of P. donghaiense, and the whole process could be finished in about six hours, which provided a new approach in high-throughput sampling and long-term monitoring of P. donghaiense.

关键词： Prorocentrum donghaiense ribosomal RNA S1 enzyme sandwich hybridization integrated with nuclease protection assay (NPA-SH)

Effect of Ultrafine Grinding on Dissolving-out Quantity of Tanshinone IIA from Radix Salvia Miltiorrhiza

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Journal of Wuhan univer.ity of Technology(Materials Science) 2009年第6期24卷 973-976页

作者：苏艳丽傅正 college of Chemistry Chemical Engineering and Material ScienceSoochow UniversitySuzhou China State Key Laboratory of Advanced Technology for Material Synthesis and Processing Wuhan University of Technology

In order to improve the bioavailability, Radix salvia miltiorrhiza raw powder mixed with distilled water （5.5wt%） was ultrafinely ground to nanosize particles using HSCS pulverizer, and the dissolving-out quantity of tanshinone IIA in the filtrate that obtained from nanoparticles suspension and raw powder marinated in water for different time was determined by HPLC. The experimental results show that raw powder can be ultrafinely ground to 133.5 nm at 1500 r/min for 50 min and the molecular structure of active ingredients doesnot change, and the dissolving-out quantity of tanshinone IIA obtained from the filtrate is increased greatly from 12.77 μg/g to 54.55 μg/g.

关键词： Radix salvia miltiorrhiza tanshinoe IIA HPLC dissolving-out quantity

Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science china Chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3 1. college of Chemistry & Environment Protection Engineering, Southwest univer.ity for Nationalities, Chengdu 610041, {2. 2. TH-UNIS Insight Co., Ltd., Beijing 100085, {2. 3. Key Laboratory of Bioorganic Phosphorus Chemistry & chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua univer.ity, Beijing 100084, {2. college of Chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu China TH-UNIS Insight Co. Ltd. Beijing China Key Laboratory of Bioorganic Phosphorus Chemistry & chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

Synthesis of todorokite by refluxing process and its primary characteristics

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Science china Earth Sciences 2004年第8期47卷 760-768页

作者： FENG Xionghan1, LIU Fan1, TAN Wenfeng1, LIU Xiangwen2.& HU Hongqing1 1. college of Resources and Environment, Huazhong Agricultural univer.ity, Wuhan 430070, {2. 2. Testing Center, {2. univer.ity of Geosciences, Wuhan 430074, {2. college of Resources and Environment Huazhong Agricultural University Wuhan China Testing Center China University of Geosciences Wuhan China

Single phase and well-crystallined todorokite were synthesized by heating and refluxing process from birnessite as a precursor. The average chemical composition of the synthesized todorokites by refluxing for 8 h and for 2. h was Mg0.19MnO2.11(H2.)1.15 and in0.17-MnO2.10(H2.)0.88, respectively. The crystallinity of the todorokite increased and no other phase was produced with increasing refluxing period. The synthesized todorokites have the same morphologies and the similar structural characteristics with the natural todorokites and hydro-thermally synthesized samples. The chemical compositions of the synthetic tordorokites by refluxing process are close to those of todorokites synthesized by hydrothermal process, except a higher average oxidation state of Mn for the former.

关键词： todorokite,birnessite,manganese oxide,refluxing,hydrothermal,synthesis.

Formation of complexes of Rubisco-Rubisco activase from La^3+, Ce^3+ treatment spinach

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Science china Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2.& ZHAO Guiwen3 1. college of Life Sciences, Suzhou universty, Suzhou 2.5006, {2. 2. Synchrotron Radiation Laboratory, Institute of High Energy Physics, The Chinese Academy of Science, Beijing 100039, {2. 3. chemical Department, univer.ity of Science and Technology of {2., Hefei 2.002., {2. college of Life Sciences Suzhou Universty Suzhou 215006 China

The complex of Rubisco and Rubisco activase from LaCl3-, CeCl3- treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3-, CeCl3-treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 36—39 –SH per mol enzyme, 14—2. –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3-, CeCl3 -treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3-, CeCl3- treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3+, Ce3+, spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.