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Effect of Excipients on Stability and Structure of rhCuZn-SOD Encapsulated in PLGA Microspheres

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Chemical Research in Chinese Universities 2004年第3期20卷 323-327页

作者： LIU Ling 1,2.,GE Yu 1 and YUAN Qin-sheng 1 1. State Key Laboratory of Bioreactor Engineering and institute of Biochemistry,East china University of Science and Technology,Shanghai 2.02.7,P. R. china 2. Public Health School,nanjing Medical University,nanjing 2.002.,P. R. china State Key Laboratory of Bioreactor Engineering and institute of Biochemistry East China University of Science and Technology 生物反应器工程国家重点实验室上海 200237

When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 2.,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.

关键词： Poly( DL -lactide-co-glycolide)(PLGA) microsphere Recombinant human Cu Zn-superoxide dismutase(rhCu Zn-SOD) Fourier transform infrared(FTIR) spectroscopy Protein stability Excipient

Seasonal variation of global stratosphere-troposphere mass exchange

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Progress in Natural Science:Materials International 2007年第12期17卷 1466-1475页

作者： Guo Dong1,2. Lu Daren2.and Sun Zhaobo1(1. institute of Atmospheric Sciences, nanjing University of Information Science and Technology,{2., china 2. LAGEO, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., china) institute of Atmospheric Sciences Nanjing University of Information Science and Technology Nanjing 210044 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

By Wei formula in pressure coordinate, the stratosphere-troposphere mass exchange (STME) is diagnosed globally for 44 years from 1958 to 2.01 using the European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis datasets. Regions of mass flux into the stratosphere are found over Indonesia, bay of Bangladesh and the mid-west coast of South Africa. Compensating mass outflow from the stratosphere appears mainly over mid-latitudes near large-scale troughs. Upward and downward transport of mass at the middle and high latitudes accompany with each other. Mass flux into troposphere is stronger in autumn and winter than in spring and summer. Strong downward mass flux into the troposphere occurs in eastern Asia the whole year with nearly stable sites. Although the area of eastern Asia accounts for only 5.6% of that of the northern hemisphere (NH), its net mass exchange reaches 15.83% of that of the NH, which means that research on STME of eastern Asia is greatly important to that of the NH and even the global areas. Air across the tropopause enters more from stratosphere to troposphere than that from troposphere to stratosphere, which is possibly related with systematic bias of the assimilated datasets and with persistent rise of the tropopause height. Contributions of the mass exchange and the mass flux exchange in the NH and southern hemisphere (SH) on their latitudes increase from equator to pole, with larger contributions in the NH. Mass exchange and mass flux exchange per areas at high latitudes are larger than that at low latitudes, which means greater mass exchange efficiency at high latitudes.

关键词： stratosphere troposphere mass exchange seasonal variation.

Discovery of sponge body fossils from the late Meishucunian (Cambrian) at Jinsha, Guizhou, south china

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Progress in Natural Science:Materials International 2005年第8期15卷 708-712页

作者： YANG Xinglian 1,2., ZHAO Yuanlong2. WANG Yue2.and WANG Pingli2.1. nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, nanjing 2.0008, china 2. institute of Resource and Environment, Guizhou University, Guiyang 550003, china) nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China institute of Resource and Environment Guizhou University Guiyang 550003 China

Here we report discovery of a sponge body fossil Triticispongia sp. from the base of lower Cambrian Niutitang Formation at Jinsha, Guizhou. Stratigraphically, the fossil horizon is located below Ni-Mo ore layer with the Niutitang Biota above, and is equivalent to the late Meishucunian. The species is global in shape with skeletons composed of stauractins and monaxons. Triticispongia sp. reported here may be the earliest sponge body fossils of Cambrian, which provides new information for understanding early evolution and radiation of sponge animals.

关键词： sponges Cambrian Niutitang Formation Guizhou china.

Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern china

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Science china Earth Sciences 2006年第8期49卷 881-888页

作者： WANG Jian1 & LI Shuo2.1. Cold and Arid Regions Environmental and Engineering Research institute, Chinese Academy of Sciences, Lanzhou 730000, china 2. College of Geography, {2. Normal University, {2. 2.0097, china Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China College of Geography Nanjing Normal University Nanjing China

Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern china. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2.01. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.

关键词： climatic changes, snowmelt runoff, SRM model, upper Heihe Watershed, simulating.

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Science china Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. Department of Chemistry, nanjing University of Science and Technology, nanjing 2.0094,{2. 2. institute of Chemical Materials,{2. Academy of Engineering Physics, Mianyang 62.900,{2. Department of Chemistry Nanjing University of Science and Technology Nanjing China institute of Chemical Materials China Academy of Engineering Physics Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

Zonal propagation of kinetic energy and convection in the South china Sea and Indian monsoon regions in boreal summer

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Science china Earth Sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2.,HE Jinhai 2.,TAO Shiyan 3 & JIN Zuhui 3 1.Chinese Academy of Meteorological Sciences,Beijing 100081,china 2.nanjing {2. of meteorology,nanjing 2.0044,china 3.{2. of Atmospheric Physics,Chinese Academy of Sciences,Beijing 10002.,china Chinese Academy of Meteorological Sciences Beijing China nanjing institute of {2. Nanjing China Chinese Academy of Sciences Institute of Atmospheric Physics Beijing China

Zonal propagation of kinetic energy (KE) and convection in the South china Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.

Prolonged exposure to resistin inhibits glucose uptake in rat skeletal muscles

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Acta Pharmacologica Sinica 2007年第3期28卷 410-416页

作者： Hong-qi FAN~(2.3) Nan GU~(2.3) Feng LIU~2.Li EEI~2.Xiao-qin PAN~2.Mei GUO~2.Rong-hua CHEN~(2.4) Xi-rong GUO~(2.3,4)2.Department of Pediatrics,nanjing Maternal and Child Health Hospital of nanjing Medical University,nanjing 2.0004,china 3 institute of Pediatrics Medicine,nanjing Medical University,nanjing 2.002.,china Department of Pediatrics Nanjing Maternal and Child Health Hospital of Nanjing Medical University Nanjing China institute of Pediatrics Medicine Nanjing Medical University Nanjing China

Aim:To assess the effects and mechanisms of the action of resistin on basal andinsulin-stimulated glucose uptake in rat skeletal muscle ***:Rat myo-blasts（L6）were cultured and differentiated into myotubes followed by stimula-tion with single commercial resistin（130 ng/mL,0-2. h）or cultured supernatantfrom 2.3-T cells transfected with resistin-expressing vectors（130 ng/mL,0-2. h）.Liquid scintillation counting was used to quantitate[3H]2.deoxyglucose *** translocation of insulin-sensitive glucose transporters GLUT4 and GLUT1,synaptosomal-associated protein 2.（SNAP2.）and GLUT protein content,as wellas the tyrosine phosphorylation status and protein content of insulin receptorsubstrate（IRS）-1,were assessed by Western ***:Treatment of L6myotubes with single resistin or cultured supernatant containing recombinantresistin reduced basal and insulin-stimulated 2.deoxyglucose uptake and impairedinsulin-stimulated GLUT4 *** SNAP2. protein content wasdecreased,no effects were noted in GLUT4 or GLUT1 protein *** diminished insulin-stimulated IRS-1 tyrosine phosphorylation levels withoutaffecting its protein *** effects of recombinant resistin from 2.3-T cellstransfected with resistin-expressing vectors were greater than that of single ***:Resistin regulated IRS-1 function and decreased GLUT4translocation and glucose uptake in response to *** downregulatedexpression of SNAP2. may have been partly attributed to the decrease of glucoseuptake by resistin *** observations highlight the potential role ofresistin in the pathophysiology of type 2.diabetes related to obesity.

关键词： resistin insulin glucose uptake obesity diabetes

ON TWO CONJECTURES OF THE QUADRATIC DIFFERENTIAL SYSTEMS

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Chinese Annals of Mathematics,Series B 1997年第4期18卷 429-434页

作者： ZHANG XIANG institute of Mathematics,nanjing Normal University,nanjing 2.0097,china 南京师范大学数学所江苏南京

Two conjectures in the qualitative theory of quadratic differential systems are proved under certain conditions.

关键词： Quadratic system Limit cycle Dulac function

Quantitative Evaluation for Drawability of Sheet Metal

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Journal of Materials Science & Technology 2005年第5期21卷 763-766页

作者： Zhiqing XIONG and Xuemei YANGDepartment of Mechanical Engineering, nanjing institute of Technology, nanjing 2.0013, china Department of Mechanical Engineering Nanjing Institute of Technology Nanjing 210013 China

The theoretical evaluating method is given for the drawability of the sheet with normal anisotropy. The general solution on the cracking load of deep-drawing is deduced, which is based on three kinds of hardening curve of materials most in use. The distributions of stress and strain in the deformed region and the drawing force are obtained by the numerical method. The limiting drawing ratio is calculated through computer-aided simulating test. The experiments of deep-drawing to four kinds of sheet metals express that the relative errors between the predictive and the experimental results about the cracking load and the limiting drawing ratio are within 5%. The drawability of common sheet metals can be quantitatively evaluated in precise terms by means of the theory and the method advanced in this paper.

关键词： Sheet forming Deep-drawing Formability Drawability