Purification, sequencing and biological activity of polypeptide from velvet antler

The velvet antler polypeptide CNT14 was extracted and purified by gel filtration, ion exchange chromatography and RP C, which showed a single peak in HPLC chromatography and a single band in SDS-PAGE. The molecular weight measured by MALDI/TOF/MS spectrum was 1479. 9028. The polypeptide consisted mostly of Glu, Leu, Val, Pro. The amino acid sequence of the polypeptide was detected with ESI-MS/ MS, and the sequence was E-P-T-V-L-D-E-V-C-L-A-H-G-P. The experiments of biological activity of polypeptide CNT14 in vivo were carried out, and the results show that CNT14 has stimulant effects on the growth of rat HT22 cells. Then we produced the polypeptide CNT14 according the amino acid sequence by solid phase synthesis, confirmed the sequence of the polypeptide to be consistent with the amino acid sequence of polypeptide CNT14 which was separated from the velvet antler.

Nuclear magnetic resonance studies on the effects of Rare Earth in rats urine

Male Wistar rats were administrated orally with La(NO3)(3) at doses of 0. 05, 0. 2, 2. 0, 10 and 20 mg/kg body weight. Urine was collected over a 24 h period after dosing. Resonances for a large number of low molecular weight metabolites were assigned in a high resolution H-1 NMR spectra of rat urine. The variation of some low molecular weight metabolites in urine provided a sensitive measurement of Rare Earth induced renal and liver lesions, in which DMA, DMG, urea, Kg, TMAO, succinate, citrate and amino acids have been suggested as NMR markers for renal damage and ethanol, lactate, taurine as the markers for liver damage. The method could be applicable to study of the toxicological effects of other compounds and drugs.

A unified criterion for initiation of sediment motion and inception of sheet flow under water waves

A unified criterion is developed for initiation of non-cohesive sediment motion and inception of sheet flow under water waves over a horizontal bed of sediment based on presently available experimental data. The unified threshold criterion is of the single form, U-o = 2 pi C[1 + 5(T-R/T)(2)](-1/4), where U-o is the onset velocity of sediment motion or sheet flow, T is wave period, and C and T-R are the coefficients. It is found that for a given sediment, U-o initially increases sharply with wave period, then gradually approaches the maximum onset velocity U-o = 2 pi C and becomes independent of T when T is larger. The unified criterion can also be extended to define sediment initial motion and sheet flow under irregular waves provided the significant wave orbital velocity and period of irregular waves are introduced in this unified criterion.

Fucoidan inhibits the development of proteinuria in active Heymann nephritis

Fucoidan, the sulphated polysaccharide extracted from brown seaweed, has various biological activities. The effect of fucoidan on the formation of proteinuria and renal functions in active Heymann nephritis was investigated in this study. Active Heymann nephritis was induced by administering brush border protein of rat proximal uriniferous tubules (FX1A). Fucoidan was administered by oral intubation to Heymann nephritis rats at three doses (50, 100 and 200 mg/kg) once daily for 4 weeks. The elevated urinary protein excretion and plasma creatinine due to the induction of Heymann nephritis were significantly reduced by fucoidan at doses of 100 and 200 mg/kg. The results indicated that fucoidan has a renoprotective effect on active Heymann nephritis and is a promising therapeutic agent for nephritis. Copyright (c) 2005 John Wiley F Sons, Ltd.

Antioxidant activities of sulfated polysaccharide fractions from Porphyra haitanesis

Three sulfated polysaccharide fractions (F1, F2, and F3) were isolated from Porphyra haitanesis, an important economic alga in China, through anion-exchange column chromatography and their in vitro antioxidant activities were investigated in this study. Galactose was the main sugar unit of the three fractions. The analytical results indicated that polysaccharide fractions from P. haitanesis had similar chemical components to porphyran from other species, but differed in their high sulfate content. The sulfate content of F1, F2 and F3 was 17.4%, 20.5% and 33.5% respectively. All three polysaccharide fractions showed antioxidant activities. They had strong scavenging effect on superoxide radical, and much weaker effect on hydroxyl free radical. Lipid peroxide in rat liver microsome was significantly inhibited, and H2O2 induced hemolysis of rat erythrocyte was partly inhibited by F1, F2 and F3. Among them, F3 showed strongest scavenging effect on superoxide radical; F2 had strongest effect on hydroxyl radical and lipid peroxide.

Stratification by solid particle suspensions

Turbulence was generated by an oscillating grid above a bed of sediment of spherical glass beads. As expected, part of the sediment was lifted up by the grid action and a suspension layer of depth D formed above the grid. This depth was found remaining independent of grid action but varying with the sediment layer depth when the grid action was kept constant. Volume concentration measurements show the existence of only weak concentration gradients over the layer depth with a rapid fall off in concentration at the outer edge. The theoretical analysis based on a concentration flux model is in good qualitative agreement with observations.

微模式化基底上大鼠骨髓间充质干细胞的增殖、分化和迁移

目的 利用微模式化基底研究基底几何微结构对骨髓间充质干细胞增殖、分化及迁移过程的影响.方法 设计制作微模式化基底,用以控制细胞的铺展形态和面积.比较不同模式控制下大鼠骨髓间充质干细胞的增殖、分化和迁移数据.结果 细胞铺展宽度狭小可抑制骨髓间充质干细胞的增殖,细胞铺展形状可以调节其向成骨细胞分化的进程,细胞铺展面积受限时迁移增强,其增殖迁移行为减弱与成骨细胞诱导因子地塞米松的作用有关.结论 细胞铺展的几何形状和面积是骨髓间充质干细胞增殖、分化及迁移过程中的重要调节因子.

三七总皂苷对大鼠海马CA1区突触传递的作用及机制

下载PDF阅读器目的 研究三七总皂苷(Panax notoginseng saponins,PNS)对大鼠海马脑片CA1区锥体神经元兴奋性和抑制性突触传递的作用.方法 断头法分离3～4周雄性Wistar大鼠海马半脑,用切片机切出400μm厚度的海马脑片,对CA1区锥体细胞采用"盲法"全细胞膜片钳技术记录,分别检测和分析PNS(0.05～0.4 g/L)对刺激CA1传人纤维引出的兴奋性突触后电流(EPSCs)和抑制性突触后电流(IPSCs)的影响,继而以脉冲间隔为50 ms的配对刺激代替单刺激,通过EPSC2/EPSC1(P2/P1)值的变化观察PNS对双脉冲易化(paired-pulse facilitation,PPF)的影响.结果 0.1～0.4 g/L PNS显著抑制EPSCs(P＜0.05),且PNS在抑制P1、P2的同时明显升高P2/P1值(P＜0.05),加强了双脉冲易化,但PNS对IPSCs无显著影响(P＞0.05).结论 PNS 显著减小大鼠海马CA1区锥体神经元的EPSCs而不影响IPSCs,说明PNS不是通过强化抑制性中间神经元的功能间接地抑制兴奋性神经元,而是对兴奋性突触传递直接产生抑制;PNS明显升高P2/p1值,说明 PNS是通过突触前机制抑制CA1区兴奋性突触传递.

BCNU-loaded PEG-PLLA ultrafine fibers and their in vitro antitumor activity against glioma C6 cells

The purpose of the present study was to develop implantable BCNU-toaded poly(ethylene glycol)poly(L-lactic acid) (PEG-PLLA) diblock copolymer fibers for the controlled release of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). BCNU was well incorporated and dispersed uniformly in biodegradable PEG-PLLA fibers by using electrospinning method. Environmental Scanning Electron Microscope (ESEM) images indicated that the BCNU-loaded PEG-PLLA fibers looked uniform and their surfaces were reasonably smooth. Their average diameters were below 1500 nm. The release rate of BCNU from the fiber mats increased with the increase of BCNU loading amount. In vitro cytotoxicity assay showed that the PEG-PLLA fibers themselves did not affect the growth of rat Glioma C6 cells. Antitumor activity of the BCNU-loaded fibers against the cells was kept over the whole experiment process, while that of pristine BCNU disappeared within 48 h. These results strongly suggest that the BCNU/PEG-PLLA fibers have an effect of controlled release of BCNU and are suitable for postoperative chemotherapy of cancers.

Arabinogalactan as a carrier for contrast agent in magnetic resonance imaging

Arabinogalactan-Gd-DTPA was synthesized by the reaction of diethylenetriaminepenta-acetic acid (DTPA) bisanhydride with polysaccharide in dry DMSO and characterized by FTIR, elemental analysis and ICP-AES. Its stability was investigated by competition with Ca2+, EDTA, DTPA. The t(1)-relaxivity is 8.06 mmol(-1) . L . s(-1) in D2O, 8.48 mmol(-1) . L . s(-1) in 0.725 mmol . L-1 BSA, respectively. t(1)-weighted MR imaging of rat kidney and liver showed a remarkable enhancement post injection of Arabinogalactan-Gd-DTPA. The results indicate that the arabinogalactan-Gd-DTPA is a potential contrast agent for MRI.

丘陵油田三间房组储层三维地质模型和砂体预测

This paper is belonging to Chinese Petrochemical Corporation's science and technology project. Although it is difficult, it has important theoretical and practical value. The study was aimed to reveal inhomogeneity of two kinds of reservoirs of fan-shaped delta and braided river by using new theories, new methods and new technology about 3-D model building and reservoir knowledge repository throughout the world, and to build reservoir knowledge repository and 3-D geological model which would predict the type of sand body forming reason and distribution rule in order to improve exploration result in Qiuling oil fields. Multi-discipline theories such as petroleum structure geology, reservoir geology, petroleum geology, sequence geology, logging geology, geomathematics and so on are used as guide. The information of geology, seism, logging and production test is combined. Outcrop area and overlap area are combined. By making full use of computer, stable structure, reservoir geometric shape, spatial distribution and inhomogeneity of bed of interest are investigated, described and characterized. Petroleum pool 3-D static geological model of reservoir knowledge repository was built. Sand body distribution was predicted. It has guided oil development, lowed the investment and improved development benefits. Several results are achieved as follows: (1) Strata framework of Sanjianfang group in Qiuling oil field has been established. (2) Geometric shape, spatial distribution and evolve rule of two different forming reason's reservoir of fan-shaped delta and braided river of Sanjianfang group in Qiuling oil field are discussed. (3) The two kinds of reservoirs have lower pore and permeability and very strong inhomogeneity. (4) Reservoir knowledge repository of two different forming reasons has been built of Sanjianfang group, which includes 5 geological knowledge sublibrary. (5) 3-D geological model of two kinds of forming reason's reservoirs has been built. (6) That same sequence instruction a simulation and probability field were used to predict sand body of Sanjianfang group was put forward. Coincidence rate is high after production test. It shows this method has great popularity value. (7) A set of theories, methods and technologies of knowledge repository of two kinds of reservoir of braided river and fan-shaped delta and 3-D geological model building were finished. (8) A set of theories, methods and technologies of investigating, describing, characterizing and predicting two kinds of oil pool were developed. It gets noticeable economic benefit after exploration. Theory and method about extrusion basin are developed.

黄骅坳陷高尘头地区储层非均质性及成藏研究

Gaochentou region is located in the southwest direction of Gaochentou village in Huanghua city of Hebei province. In regionally structural position, It lies in Qikou sag In the middle part of Huanghua depression, which belongs to the east part of the south Dagang structure zone in the middle part of Huanghua depression. Its' very beneficial at regional structure in Gaochentou , and It becomes the advantage area for oil and gas gathered and preserved, Sandstone reservoir of Dongying Formation is main bearing bed .Dongying Formation in Gaochentou region of Huanghua depression is consisted of set of mudstone and sandstone interbeds by deposited delta fades . Dongying Formation can be divided into 3 members from above to below: the first member of Dongying Formation (FMDF), the second member of Dongying Formation (SMDF), and third member of Dongying Formation (TMDF). The lithology of the upper part of FMDF was consisted of mostly middle-grained and fine-grained sandstone, and it is small for the oil-bearing area of the sand bodies .The lithology of the lower part is coarse-grained sandstone bodies which are well connected between sandstone bodies of wells, and the lower part was main bed of oil production in Dongying Formation; SMDF and TMDF are consisted of larger scale set of mudstone, in which the sandbodies are lenticular and pinch out quickly, and the lithology was mostly fine sandstone and silt stone, in which there are little oil and gas .Because the reservoirs in this area are largely influenced by the factors such as lithology, fault and others, and the reservoirs have the strong,heterogeneity , there exists the problem of oil-down and water-up for vertical distribution of oil and gas bearing. It is not very clearly for the three dimension distribution of sandstone , and the geology researchs is not enough. So, it can't satisfy the need of further development and production for Gaochentou oilfield.Having the key problem of oil-down and water-up and the mechanism of the reservoir for Gaochentou area, There are as follow study works, the first, is study of the high-resolution correlation of sequence stratigraphy and sedimentary microfacies. Dongying Formation was divided into three parasequence sets and each parasequence set was divided into different amount of parasequences. FMDF, as the main oil and gas producing bed, can be divided into seven parasequences. Oil and gas are discovered in six parasequences except the seventh. On the basis of study of sedimentary microfacies, the sediments of Dongying Formation are considered deposited mainly in delta front subfacies. The microfacies types of Dongying Formation are sub-water distirbutary channel, sub-water natural bank, inter distributary channel bay, distributary channel mouth dam, and delta front mat sand.Seismic facies analysis and logging-constrained inversion technique were applied by Author for transverse prediction of sandstone reservoir. Having 4 modes of interwell single sandbodies correlation technique, Author have described distribution characteristics of sandbodies, and established geological reservoir model of Gaochentou reservoir.Author presented that the reservoirs characteristic have very strong heterogeneity ,and In the section of sandstone interlayed with mudstone,the folium sandstone interlayed with each other, and the wedge shaped sandbodies pinched out in the mudstone. So the pinch-out up sandstone trap and lenticular sandstone trap are easily formed. They are most small scale overlying pinches out in the place of slope. This article applies the concept of deep basin oil to resolve reasonably the problem of which the oil is below the water in Gaochentou area. Combined with the study of sedimentary facies, reservoir and other aspects, the mechanism and patterns of deep basin oil are studied on the basis of characteristics in Gaochentou area.On the basis of the above study, the mechanism of the oil and gas' migration and accumulation in isotropic sandstone and heterogeneous sandstone are thoroughly analyzed through experiments on physical modeling. Experiments on physical modeling show that the discrepancy between sand layers with different permeability and thickness has important influence on the direction, path, and injection layer of oil's migration. At the beginning of the injection of oil and gas in high permeability sand layer, the pressure is low, the migration resistance is small, and the oil and gas are more easily displacing the water in sand. So it can act as good transformation layer or reservoir. But at the beginning of the injection of oil and gas in sand layer with low permeability, the pressure is high, the migration resistance is big, and the oil and gas are more difficultly displacing the water in sand. So it can only act as bad or worse transformation layer or reservoir. Even if it cannot act as transformation layer or reservoir, it can act as water layer or dry layer. The discrepancy between sand layers on permeability and thickness can make discrepancy in injection of oil and gas between different layers. Consequently it leads to small amount of oil and gas injection in sand layers with low permeability. Ultimately it affects the oil's accumulation and distribution in different sand layers.At Last, combining analysis of the structure and pool forming condition, The thesis has established models of reservoir formation to predict the advantage distribution of oil and gas bearing , and put forward the prospective target It is not only of theoretical signification for explosion and importance, but also has realistic value in guiding the progressive petroleum exploration and exploitation.