司帕沙星对试验动物的一般药理研究

小鼠单次经口灌服司帕沙星4、20和100mg/kg后,动物的活动正常,未出现兴奋的抑制作用;小鼠单次经口灌服司帕沙星4、20和100mg/kg,与戊巴比妥钠镇静催眠无明显协同作用;给猫静脉注射司帕沙星4、16和64mg/kg,对动物呼吸和心血管系统无明显影响。     

A tctex1-Ca2+ channel complex for selective surface expression of Ca2+ channels in neurons

Voltage-gated Ca(2+) channels (VGCCs) are important in regulating a variety of cellular functions in neurons. It remains poorly understood how VGCCs with different functions are sorted within neurons. Here we show that the t-complex testis-expressed 1 (tctex1) protein, a light-chain subunit of the dynein motor complex, interacts directly and selectively with N- and P/Q-type Ca(2+) channels, but not L-type Ca(2+) channels. The interaction is insensitive to Ca(2+). Overexpression in hippocampal neurons of a channel fragment containing the binding domain for tctex1 significantly decreases the surface expression of endogenous N- and P/Q-type Ca(2+) channels but not L-type Ca(2+) channels, as determined by immunostaining. Furthermore, disruption of the tctex1-Ca(2+) channel interaction significantly reduces the Ca(2+) current density in hippocampal neurons. These results underscore the importance of the specific tctex1-channel interaction in determining sorting and trafficking of neuronal Ca(2+) channels with different functionalities.     

125I-白细胞介素-8在小鼠体内的分布研究

为了解白细胞介素 - 8的体内行为 ,用 Bolton- Hunter法对 IL- 8进行 1 2 5I标记 ,并测定它在小鼠体内的分布 ;得到了 1 2 5I- IL- 8在小鼠血、心、肝、肺、肾、骨、脾等脏器中的分布以及它在血液中的快相半排期 T1 /2α为 0 .3 2 h和慢相半排期 T1 /2β为 8.0 1h。1 2 5I- IL- 8主要通过肾排除     

Human granulocyte-macrophage colony-stimulating factor (hGM-CSF): identification of a binding site for a neutralizing antibody.

One approach to the localization of functionally active regions of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) is to map the epitopes recognized by neutralizing anti-hGM-CSF monoclonal antibodies. We have defined the epitope recognized by one neutralizing antibody (LMM102) using proteolytic fragments obtained by enzymic digestion of bacterially synthesized hGM-CSF. RP-HPLC fractionation of a tryptic digest resulted in the identification of an immunoreactive "tryptic core" peptide containing 66 amino acids (52% of the protein). Further digestion of this "tryptic core" with S. aureus V8 protease produced a unique immunoreactive hGM-CSF product comprising two peptides, residues 86-93 and 112-127, linked by a disulfide bond between residues 88 and 121. The individual peptides, generated by reduction with dithiothreitol, were not recognized by the antibody. An analog of this peptide has been synthesized chemically and shown to have similar immunoreactivity to the epitope obtained by enzymic digestion. A series of modified peptides has also been synthesized to identify further the region required for antibody recognition.     

Temperature rising elution fractionation of a random ethene/styrene copolymer

A random ethene/styrene copolymer containing 13.8 mol-% styrene was prepared with the Ziegler-Natta catalyst system Me₂Si(Me₄Cp)(N-t-butyl)TiCl₂/methylaluminoxane and characterized by means of preparative temperature rising elution fractionation (TREF) combined with size exclusion chromatography, NMR, differential scanning calorimetry and wide-angle X-ray scattering analyses of the copolymer fractions. Efforts are made to describe the distribution of the styrene content of the copolymers using the Stockmayer-Tacx distribution function. Both, comonomer distribution and molar mass distribution strongly support the presence of a single type of catalytically active center.     

Novel micro-crosslinked poly(organophosphazenes) with improved mechanical properties and controllable degradation rate as potential biodegradable matrix

As biodegradable materials, linear polyphosphazenes undergo rapid hydrolysis degradation but exhibit poor mechanical properties. Blending with biodegradable polyesters or inorganic particles strengthen their mechanical properties but give rise to slower degradation rate. To balance the mechanical properties and the degradation rate, micro-crosslinked polyphosphazenes were synthesized in this study. Their glass transition temperatures, mechanical properties, and in vitro degradation behavior were investigated. 2-hydroxyethyl methacrylate (HEMA) was firstly attached to the side chain along with glycine ethyl ester to prepare co-substituted poly(organophosphazene) with pendant ethenyl substituents. The co-substituted poly(organophosphazene) was blended with HEMA or acrylic acid (AA) followed by a free radical polymerization to prepare micro-crosslinked poly(organophosphazenes). The resulting crosslinked polymers showed two separate glass transition temperatures depending on the HEMA or AA feed. Incorporation of crosslinking affected the mechanical properties positively. Crosslinked poly(organophosphazenes) showed an approximately 11-17 fold increase in terms of modulus of elasticity when compared to the linear counterpart. In vitro degradation tests indicated that HEMA-crosslinked polymers hydrolyzed at a retarded rate while AA-crosslinked polymers hydrolyzed at a moderate rate compared to linear polymers.     

Structural characterization of the C4a anaphylatoxin from rat

The C4a anaphylatoxin was purified from rat sera activated by heat-aggregated IgG. The anaphylatoxin was isolated by a three-step purification procedure and was judged to be homogeneous based on visualization of a single stained band after electrophoresis on both cellulose acetate membrane strips and on 9% SDS-polyacrylamide gels. Results from Ouchterlony and radioimmunoassay analysis indicated that neither rat C5A nor C3a contaminated the C4a preparation. Rat C4a is a glycoprotein estimated to be 11,000-12,000 mol. wt and contains 76 amino acid residues representing a mol. wt of 8577 and one oligosaccharide unit of 2000-3000 mol. wt. Rat C4a is weakly active in contracting guinea pig ileum at 0.1-1 microM, which is comparable with the activity of human C4a. Both human and bovine C4a are polypeptides free of carbohydrate while rat and presumably mouse C4a are glycoproteins. The complete primary structure of rat C4a anaphylatoxin has been elucidated as follows: (formula; see text)     

人肝癌组织中p53与HSP70相互作用的初步研究

目的 :探讨人肝癌中热休克蛋白 70 (HSP70 )与 p5 3的相互作用。方法 :用免疫组织化学染色法 ,从 12例肝癌组织中筛选HSP70与 p5 3均呈阳性表达的标本 ,并以免疫共沉淀法提取之。然后用SDS PAGE及Westernblot分析双阳性标本中两种蛋白的存在形式。结果 :用免疫组织化学法检测到 12例肝癌组织中有 3例为双阳性 ,用抗HSP70mAb免疫共沉淀的样品 ,可检测到 p5 3蛋白。用抗p5 3mAb免疫共沉淀的样品也可检测到HSP70蛋白。结论 :人肝癌中p5 3与HSP70以复合物的形式而存在 ,此可为肝癌的发病机制及免疫治疗的研究提供新的思路     

脑梗死患者血浆神经肽Y、降钙素基因相关肽、神经降压素、胃动素动态变化及其临床意义

观察脑梗死(CI)患者神经肽Y(NPY)、神经降压素(NT)、胃动素(MTL)、降钙素基因 相关肽(CGRP)浓度变化及其临床意义。方法选择C162例,用放免法检测血浆NPY、NT、MTL与CGRP浓度。结果NPY、NT与MTL浓度显著高于对照组(P<0.0001);于发病后24h内显著升高,7d内达高峰,8～15d开始下降,15d后仍在较高水平。NPY浓度重型与大灶组显著高于轻型(P<0.05)与小灶组(P<0.01);发病积分≥6分组显著高于<6分组(P<0.05);高血压组显著高于正常血压组(P<0.05)。NT与MTL浓度重型组显著高于中(P<0.05)、轻型组(P<0.01);高血糖组显著高于正常血糖组(P<O.01)。CGRP浓度显著低于对照组(P<0.0001),发病24h内即显著降低,2～7d进一步降低,8～15d开始升高,15d后逐渐升至正常水平。重型与大灶组显著高于轻型(P<0.0001)、中型(P<0.01)与小灶组(P<0.01);伴发病积分≥6分组显著低于<6分组(P<0.05)。结论CI患者NPY、NT、MTL、CGRP浓度变化以7d内最显著,15d后逐渐恢复正常水平;四种浓度监测可作为判断CI患者病情严重程度、病灶大小及伴发病的实验室指标。