Membrane cartridges for endotoxin removal from interferon preparations

The suitability of membrane cartridges for the removal of endotoxin from both distilled water and interferon preparations was examined. The endotoxin concentrations were reduced to 4.0 and 7.3 EU/ml, respectively, when about 4000 ml of distilled water with 20 and 28 EU/ml were passed through the deoxycholate and chitosan immobilized membrane cartridges. When 200 ml of interferon preparation with endotoxin concentration more than 80 EU/ml and pH 3.9 were applied to a deoxycholate immobilized membrane cartridge at a flow-rate of 9 ml/min, the endotoxin concentration was reduced to less than 10 EU/ml. However, if an interferon preparation of 450 ml, with more than 80 EU/ml of endotoxin and pH 3.9 was applied to the chitosan immobilized membrane cartridge at a flow-rate of 18 ml/min, the endotoxin concentration was reduced to less than 10 EU/ml. (C) 2003 Elsevier Science B.V. All rights reserved.

THE CHROMOSOMES OF TUFTED DEER (ELAPHODUS-CEPHALOPHUS)

Mitotic and meiotic chromosome preparations of the tufted deer (Elaphodus cephalophus) were studied to elucidate the sex-chromosomal polymorphism evidenced by this species. Females had 2n = 46 or 47 chromosomes, whereas males had 2n = 47 or 48 chromosomes. An X;autosome translocation was identified by synaptonemal complex analysis of spermatocytes at pachytene and confirmed by the presence of a trivalent at diakinesis/metaphase I. The present work, in combination with earlier observations by others, indicates that E. cephalophus possesses a varied X-chromosome morphology involving an X;autosome translocation and addition of varying amounts of heterochromatin. It is speculated that sex-chromosome polymorphism may be responsible for the observed differences in diploid chromosome number of tufted deer.

Transplantable neural progenitor populations derived from Rhesus monkey embryonic stem cells

Cell-based therapies using embryonic stem cells (ESCs) in the treatment of neural disease will require the generation of homogenous donor neural progenitor (NP) populations. Here we describe an efficient culture system containing hepatocyte growth factor (HGF) and G5 supplement for the production of highly enriched (88.3% +/- 8.1%)populations of NPs from rhesus monkey ESCs. Additional purification resulted in NP preparations that were 98% nestin positive. Moreover, NPs, as monolayers or neurospheres, could be maintained for prolonged periods of time in media containing HGF+G5 or G5 alone. In vitro differentiation and in vivo transplantation assays showed that NPs could differentiate into neurons, astrocytes, and oligodendrocytes. The kinds and quantities of differentiated cells derived from NPs were closely correlated with their niches in vivo. Glial differentiation was predominant in periventricular areas, whereas cells migrating into the cortex were mostly neurons. Cell counts showed that 2 months after transplantation, approximately 25% of transplanted NPs survived and 65% - 80% of the surviving transplanted cells migrated along the ventricular wall or in a radial fashion. Subcloning demonstrated that several clonal lines derived from NPs expressed nestin and differentiated into three neural lineages in vitro and in rat brains in vivo. In contrast, some subcloned lines showed restricted differentiation both in vitro and in vivo in rat brains. These observations set the stage for obtaining highly enriched NPs and evaluating the efficacy of NP-based transplantation therapy in the nonhuman primate and will provide a platform for probing the molecular mechanisms that control neural induction.

Development and characterization of monoclonal antibodies to spring viraemia of carp virus

Five monoclonal antibodies (mAbs) against spring viraemia of carp (SVCV0504, isolated from common carp in China) were produced from mice immunized with purified virus preparations. The virion of SVCV contains five structural proteins, representing the nucleoprotein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G) and RNA-dependent RNA polymerase (Q. Western blotting analysis revealed that three mAbs (1145, IE10, and 11-17) recognized specifically to a single protein of 47 kDa (N), the mAb 3G4 reacted with, two SVCV0504 proteins of 69 kDa (G) and 47 kDa (N), while the mAb 1A9 reacted with three SVCV0504 proteins of 69 kDa (G), 50 kDa (P), and 47 kDa (N). By indirect ELISA, two mAbs (1H5 and 11-17) showed cross-reactivity with pike fry rhabdovirus (PFRV), but no cross-reactions with the Siniperca chuatsi rhabdovirus (SCRV), Scophthalmus maximus rhabdovirus (SMRV), Paralichthys olivaceus rhabdovirus (PoRV) were demonstrated with the five mAbs. Indirect immunofluorescence showed intense fluorescence in the cytoplasm of the SVCV0504-infected epithelioma papulosum cyprini (EPC) cells in areas corresponding to the location of granular structures. The sucrose gradient-purified SVCV0504 particles could be detected successfully by these mAbs using immunodot blotting. mAb 1A9 could completely neutralize 100 TCID50 (50% tissue culture infective dose) of SVCV0504 at a dilution of 1:8. This is the first report of development of the neutralizing mAbs against SVCV. The mAb 1A9 was analyzed further and could be used to successfully detect viral antigens in the infected-EPC cell cultures or in cryosections from experimentally infected crucian carp (Carassius auratus) by immunohistochemistry assay. Furthermore, a flow cytometry procedure for the detection and quantification of cytoplasmic SVCV0504 in cell cultures was developed with mAb 1A9. At 28 h after inoculation with the virus (0.01 PFU/cell), 10.12% of infected cells could be distinguished from the uninfected cells. These mAbs will be useful in diagnostic test development and pathogenesis studies for fish rhabdovirus. (c) 2008 Elsevier B.V. All rights reserved.

Hydrodynamics in an expanded bed of large size ion-exchange resin, and natural product adsorption

Successful applications of expanded bed adsorption (EBA) technology have been widely reported in the literature for protein purification. Little has been reported on the recovery of natural products and active components of Chinese herbal preparations using EBA technology. In this study, the hydrodynamic behavior in an expanded bed of cation resin, 001 x 7 Styrene-DVB, was investigated. Ephedrine hydrochloride (EH) was used as a model natural product to test the dynamic binding capacity (DBC) in the expanded bed. EBA of EH directly from a feedstock containing powdered herbs has also been investigated. These particles are different from commercially available expanded bed adsorbents by virtue of their large size (20S to 1030 gm). When the adsorbent bed is expanded to approximately 1.3 to 1.5 times its settled bed height, the axial liquid-phase dispersion coefficient was found to be of the order 10(-5) m(2) s(-1), which falls into the range 1.0 x 10(-6) to 1.0 X 10(-5) m(2) s(-1) observed previously in protein purification. Because of the favorable column efficiency (low axial dispersion coefficient), the recovery yield and purification factor values of EH directly from a feedstock reached 86.5% and 18, respectively. The results suggest that EBA technology holds promise for the recovery of natural products and active components of Chinese herbal preparations.

Studies on polysaccharides from three edible species of Nostoc (Cyanobacteria) with different colony morphologies: Comparison of monosaccharide compositions and viscosities of polysaccharides from field colonies and suspension cultures

Hot water-soluble polysaccharides woe extracted from field colonies and suspension cultures of Nostoc commune Vaucher, Nostoc flagelliforme Berkeley et Curtis, and Nostoc sphaeroides Kutzing. Excreted extracellular polymeric substances (EPS) were isolated from the media in which the suspension cultures were grown. The main monosaccharides of the field colony polysaccharides from the three species were glucose, xylose, and galactose, with an approximate ratio of 2:1:1. Mannose was also present, but the levels varied among the species, and arabinose appeared only in N. flagelliforme. The compositions of the cellular polysaccharides and EPS from suspension cultures were more complicated than those of the field samples and varied among the different species. The polysaccharides from the cultures of N. flagelliforme had a relatively simple composition consisting of mannose, galactose, glucose, and glucuronic acid, but no xylose, as was found in the field colony polysaccharides. The polysaccharides from cultures of N. sphaeroides contained glucose (the major component), rhamnose, fucose, xylose, mannose, and galactose. These same sugars were present in the polysaccharides from cultures of N. commune, with xylose as the major component. Combined nitrogen in the media had no qualitative influence on the compositions of the cellular polysaccharides but affected those of the EPS of N. commune and N. flagelliforme. The EPS of N. sphaeroides had a very low fetal carbohydrate content and thus was not considered to be polysaccharide in nature. The field colony polysaccharides could be separated by anion exchange chromatography into neutral and acidic fractions having similar sugar compositions. Preliminary linkage analysis showed that 1) xylose, glucose, and galactose were 1-->4 linked, 2) mannose, galactose, and xylose occurred as terminal residues, and 3) branch points occurred in glucose as 1-->3,4 and 1-->3,6 linkages and in xylose as a 1-->3,4 linkage. The polymer preparations from field colonies had higher kinematic viscosities than those from corresponding suspension cultures. The high viscosities of the polymers suggested that they might DE suitable for industrial uses.

BIODIESEL PRODUCTION FROM DIFFERENT FEEDSTOCKS IN PILOT SCALE SYSTEM

In this study, the preparations of biodiesel from three different feedstocks, including rapeseed oil, high acidified Chinese wood oil and trap grease, were carried out in a pilot scale of 200 t yr(-1) biodiesel production system. The optimum operating conditions for transesterification of rapeseed oil in plug flow reactor were found to be as follows: the catalyst dosage is 1.2 wt%; the retention time is about 17 min; the bed temperature is 65 degrees C; the oil/methanol ratio is 1:6; the content of methyl ester is 96.33% under these conditions. A kind of ion exchange resin, a solid acid catalyst, filled in the fixed bed reactor was used as the esterification catalyst for the pretreating of high acidified oil. The acid value of Chinese wood oil could be reduced from 7 to 0.8 mg KOH.g(-1) after 88 min, the optimum operating conditions were obtained as follow: molar ratio of methanol to oil is about 6:1, the temperature of the fixed bed, 65 degrees C and the retention time, about 88 min. Also a kind of acidified oil, namely trap grease, with the acid value being 114 mg KOH.g(-1) could be equally converted to a good biodiesel product through this system. Generally, the refined biodiesel product generated through this system could meet China #0 Biodiesel Standard, as well as Germany Biodiesel Standard for most indexes. It indicates that the designed process in this system has a good adaptability for different kinds of oil.

固体氧化物电解质的合成及电学性质的研究

世界能源短缺和环境污染问题日趋严重，因此需要发展能源转换效率高、对环境污染低并便于应用的绿色能源技术。固态氧化物燃料电池（SOFC，Solid Oxide Fuel Cell）因其效率高、对环境友好等优点被认为是二十一世纪最有前景的能源技术。SOFC的关键是固体电解质的研究。目前广泛使用的固体电解质8YSZ（8mol%Y2O3稳定化的ZrO2）仅在1000oC以上有高的电导率。所以，探索新的、在中温区具有高离子电导率的电解质材料具有重要的意义。另外，也可以采用新的方法改善固体氧化物电解质的导电性，比如掺杂、将材料纳米化等。 在本论文中，通过共沉淀法合成了La2Mo2O9化合物，并与溶胶凝胶法合成的样品进行比较，在同样的烧结条件下，共沉淀法合成的La2Mo2O9化合物具有更高的致密度，而且由于很少引入杂质，电导率得到明显提高，在800oC时达到0.15 S.cm-1。利用同样的方法通过对La2Mo2O9进行微量磷的掺杂，降低了材料在高温时的相转变温度，基本实现了低温电导率的提高。另外，我们还对La2Mo2O9化合物进行了高压烧结研究。实验表明，La2Mo2O9纳米粉末经过700oC高压烧结后得到了致密样品，样品保持了纳米尺度，相对密度达到99％。样品由原先单斜相的La2Mo2O9变为镧钼化合物的混合物，当其在常压下800oC退火后样品又回复到单一的La2Mo2O9相，此时样品粒径大约为50nm，通过这种方法，纳米La2Mo2O9陶瓷被制得。 通过在不同温度高压烧结的方法得到了致密的8YSZ材料。样品的相结构对电导率有很大的影响，在1450oC高压烧结10min得到了立方相与少量四方相的样品，由于具有很高的致密度，得到了相对高的低温电导率。而在1000oC高压烧结10min后的样品，其相结构转变为四方相和单斜相，电导率也相应降低。高压烧结后的样品在1650oC常压退火后，样品又回复到立方相，其电导率又相应提高。 磷灰石结构化合物由于烧结温度很高，也可以通过高压烧结的方法在低温下得到致密烧结体。本论文中，采用高压烧结的方法得到了致密的纳米La9.33Si6O26块体材料，并与常压烧结的样品进行比较，其电导率得到了提高。但是和文献报道值比较，其电导率还是相对较低。这主要是由于样品中含有少量La2SiO5杂相。提高样品的纯度将更有利于电导率的提高。 作为固体电解质的氧化铋基材料极大地吸引了人们的兴趣。本文通过溶胶凝胶法合成了Bi2Ga4O9化合物，首次研究了它的电学性质和化学稳定性。电导率随氧分压的减小而减小，表明化合物中p型电子导电的存在。在500oC时，化合物的离子迁移数小于0.50，化合物是混合导体。

稀土与钼复合氧化物的合成、结构和电性质研究

固体氧化物燃料电池（SOFC）被称为“二十一世纪的绿色能源”。氧化忆稳定氧化错（YSZ）是目前sOFC普遍采用的固体电解质材料。由于YSZ只有在高温时（大于1000℃）才具有较高的离子导电性，而SOFC在高温时会带来一系列技术性的问题，如机械强度的不稳定、材料的老化及各构成材料之间的相互扩散等。因此，迫切需要开发在中、低温范围内（600-800℃）具有较高离子电导率（大于10-2S．cm-l）的电解质材料。在众多的候选材料中，稀土作为基体和掺杂元素的固体电解质越来越引起人们的重视。特别是萤石型化合物CeOZ、钙钦矿型化合物LaGaO3，以及阴离子空位型化合物La2MO2O9等的研究，开阔了寻找固体电解质材料的视野。本论文主要研究稀土与钥复合氧化物的合成、结构及其电学性质，希望进一步提高现有材料的导电性能和寻找新型固体电解质材料。基于母体化合物La2Mo2O9在580℃左右有一个相变点，因为存在相变点的固体电解质在实用方面（如SOFC）有很大的局限性。我们从稀土掺杂的角度出发，对母体化合物进一步改性，稳定其高温结构相。为此，我们利用改性柠檬酸盐法合成了系列化合物La2-xRExMo2O9（RE＝Ce，Pr，Nd，Sm，Gd，Tb，Dy，Ho，Er，Yb）。结果发现，只有Nd和Sm可以进入La2Mo2O9中La的格位；利用本方法合成样品的温度比用固相法低250℃左右；所合成的样品粒度分布非常均匀，并且随着Nd和Sm掺杂量的增加而变大；Nd和Sm的掺杂稳定了其高温相，电导率有所提高。从而使此类固体电解质在实用方面成为可能。合成了一种新型稀土与钥的复合氧化合物Ce6MoO15，电学性质测试发现，它是一性能优良的固体电解质材料。以此化合物为母体）进行低价金属离子的掺杂取代后发现，它们的导电性又进一步地提高，进而派生出多种固体电解质体系如Ce6-6 MoO15-δ、Ce6+x Mo1-x O15-6、Ce6Mo1-xBixO16-6以及Ce6-xAxMoO15-6。（A＝Li，Ca，Sr和Ba）等。本研究工作中主要合成了Ce6-xRExMoO16-6（RE=Pr，Nd，Sm，Gd，Tb，Dy，Ho，Er，Yb；x=0.0-6.0）等系列化合物，并对其进行了结构表征及电学性质测试。结果发现所有样品均为类莹石结构；样品的导电性起源于氧离子空位；在相同的温度下，样品电导率相当于或高于经典的固体电解质（如YSZ），并且样品的抗老化性能有所提高。所有这些实验事实证明，它们在中温区是一种高效氧离子导体，从而为此类化合物在SOFC中的应用奠定了基础。通过合成AgScMo2O8，尝试了一种钥酸盐固溶体的合成方法，即钥酸盐水溶液合成法。这种方法不需要加入有机物（如柠檬酸等）作为络合剂，而是通过钼酸根与金属离子之间的酸碱对效应直接合成。我们对此化合物的结构、电学性质进行研究后发现：此化合物在较低的温度即已完全成相；室温下，Agsco208为单斜结构，不同于AgLnMo2O8（Ln＝Y-Lu）；随着温度的升高，AgscMo2o8在485℃、539℃附近各有一个不可逆，可逆相变点出现。在可逆相变点出现的同时，伴随着其电导率有一个很大的突跃。

层状钙钛矿结构化合物的合成、电性和磁性的研究

近年来，随着金属多层膜，磁隧道结和钙钦矿锰氧化物等材料中磁阻现象的发现，以研究磁阻效应的机理和应用为目的的磁电子学迅速发展。这其中钙钦矿结构的稀土锰氧化物以其超大的磁阻值和丰富的物理内涵而备受瞩目。尽管人们对此已做了大量的工作，但是对这类氧化物的深入认识直至超大磁电阻效应物理机制的合理解释仍需做艰苦细致的努力。本论文选择层状钙钦矿稀土锰氧化物作为研究对象，系统地研究了A位，B位的变化和B位原子之间的相互作用对氧化物的结构、磁性和磁阻性质的影响。希望得到钙钦矿中磁、电性质和磁阻与结构之间的关系，能对该系列化合物中电、磁性质的变化规律和相互作用机理作出合理的解释。基于LaSr2Mn2O7的结构特殊性，我们选择了它作为母体化合物。并通过过渡金属离子Cr，Ti，Ni，Fe对Mn离子取代来研究B位原子的变化对性质的影响。结果发现，Cr3＋因为与Mn4＋具有相同的电子形态而能够参与双交换作用，使掺杂Cr3＋的系列样品的磁化强度随cr含量的增加而增加。而掺杂讨＋，Ni2＋，Fe3＋离子的化合物虽然与Mn离子之间的相互作用各不相同，但引起的磁性变化却是相同的。这四种元素的掺杂都提高了体系的磁阻和电阻率。通过对这几种过渡金属取代的比较，发现在LaS2Mn2O7中对Mn离子进行取代的离子和Mn离子之间的交换作用对磁性质的影响并不起主要作用，掺杂引起的主要作用是致使Mn位的无序度增加和对双交换作用的稀释和阻碍。值得注意的是每个系列样品中都有一个样品的磁阻在高温时出现较大的正值，且随着温度的降低转变为负值。例如，在Fe掺杂的系列样品中，只有x＝0.2的样品表现出正磁阻，且MR在28OK时达到74％。这可能是因为掺杂导致的结构变化引起的。这种正磁阻对材料的应用意义重大。电荷有序对磁阻材料是一种很重要的状态，为了提高LasrZMn2O7的电荷有序温度，我们选择了具有孤对电子的Bi3+来取代Sr2+。结果发现，单相样品只能持续到x≤0.2。样品的电荷有序温度并没有象预想的那样有所提高。这是因为体系的二维结构抑止了Bi3＋离子的作用，同时由于体系中Bi3＋的含量较少没有达到提高电荷有序温度的程度。但Tco降低的程度相对于其它离子的取代效果（如Gd）要低。目前n=3的层状钙钦矿研究较少，但是由于该化合物具有结构可变性和理论上可以解释磁转换机理，我们对（La，ca）4kMn3O10进行了深入的研究。在La3-3xCa1＋3xMn3O10（0.5≤x≤1.0）中随La3＋含量的减少，该系列化合物经历了从铁磁性到顺磁性再到反铁磁性的转变，同时在磁阻上也经历了由负磁阻（x＝0.5～0.7）到正磁阻（x=0.8-1.0）的转变。根据磁性和电性的变化规律，我们认为这种正负磁阻的转变是由于体系中超交换和双交换作用的相互竞争引起的。La3＋含量多时，Mn3十离子含量较多，双交换作用占主导地位，产生负磁阻；随着Mn3+离子含量的减少，双交换作用逐渐减弱，Mn4+离子之间的反铁磁性超交换作用逐渐增强，产生了正磁阻。在低掺杂浓度时LaxCa4-xMn3O10（x＝0-0.9）经历了顺磁性到反铁磁性的转变，为了了解其磁性变化过程，我们进一步研究了富含Mn4＋的这一区间。发现磁化强度在x≤0.2的范围内随x增加而增强，在高于0.2的掺杂范围后随x的增加而逐渐降低。这是因为这一区间的磁结构由基态时的G型-AFM向x＝0.9时的C型-AFM的转变。而且这种转变与载流子浓度密切相关。

The study on a PVC membrane electrode for gemfibrozil

In this paper, a poly(vinyl chloride) (PVC) membrane electrode is prepared for gemfibrozil, 2, 2-dimethyl-5(2,5-xylyloxy) valeric acid, based on its ion pair complexes with hexadecyltrioctyl ammonium iodide (HTOA). The membrane composition of the electrode was optimized by using the sequential level elimination method for orthogonal experimental design. The electrode has a Nernstian response range from 2.5 X 10(-5) to 0.1 mol/l with an average slope of 55.3 mV/decade. The limit of detection is 7.1 X 10(-6) mol/l. The electrode responses were not affected by pH in the range 10.0-12.3. A Na2B4O7-Na2CO3 buffer of pH = 11.0 was selected as the background electrolyte solution for potentiometric measurements. The electrode was used for determining gemfibrozil in pharmaceutical preparations with satisfactory results.

施用农用化学品及生防制剂对土壤线虫群落动态影响的研究

Dynamics of soil nematode communities amended with agrochemicals and bio control preparations were investigated in a soybean field. The results showed that the frequency of plant non parasitic nematodes were obviously higher in soil amended with bio control preparations (Doufeng 1) than with urea and herbicide, however, that of plant parasitic nematodes exhibited an inverse trend.

Separation and detection of chlorpromazine hydrochloride and promethazine hydrochloride using electrochemiluminescence followed by capillary electrophoresis

Phenothiazine drugs, chlorpromazine hydrochloride (CPZ) and promethazine hydrochloride (PMZ), were determined with Ru(bpy)(3)(2+) electrochemiluminescene by the capillary electrophoresis (CE-ECL). It was found that both CPZ and PMZ could produce an intermediate that acted as coreactants to react with Ru(bpy)(3)(2+) to produce excited states which were capable of emitting light. This CE-ECL detection method had high sensitivity, good selectivity and reproducibility for CPZ and PMZ determination.

Identification of herb Acanthopanax senticosus (Rupr. Et Maxim.) harms by capillary electrophoresis with electrochemical detection

In this paper, a rapid, high efficient, sensitive and inexpensive approach based on a combination of simple ultrasonic extract and capillary electrophoresis (CE) separation with electrochemical detection (ED), is described to identify herbs by comparing their CE-ED profiles (namely, CE-ED electropherograms). The proposed method takes advantage of ultrasmall sample volume, low consumption of organic solvent, simple sample pretreatment and easy cleanup procedure. It was applied to analyze the CE-ED profiles of stems of herb Acanthopanax senticosus (Rupr. Et Maxim.) Harms from different sources and different parts (roots, rhizomes, stems and leaves) of this herb. By comparing peak number, peak height and peak height ratio, we found that the CE-ED profiles showed big differences for the herbs from the different sources and the different parts of this herb. In addition, the distribution of bioactive compounds (isofraxidin, rutin and chlorogenic acid) in the different parts of this herb and their content variations affected by the source were studied with the CE-ED method. Based on their own unique CE-ED profiles, these herbs from the different sources and the different parts of this herb could be easily distinguished. Therefore, the proposed approach could be used as a rapid, high efficient and sensitive method for the identification of herbal medicines.