基于nanoUPLC-MS/MS的螺旋藻游离肽组成分析

为了研究螺旋藻中的多肽成分,以钝顶螺旋藻为原料,采用超滤法提取螺旋藻中的游离肽,利用nanoUPLC-MS/MS和PEAKS Studio分析谱图信息,结合NCBI数据库进行比对和从头测序分析,获得游离肽的结构组成和百分含量信息。结果表明,利用数据库比对法和从头测序法,分别得到可信的游离肽4 485个和20 597个,匹配到的蛋白质有1 036种。数据库比对结果中的游离肽主要为七肽到二十一肽,少量为二十一肽以上;从头测序结果中游离肽主要为二肽到十六肽,少量为十六肽以上。数据库比对结果中百分含量最高的游离肽是十肽,为15.95%;从头测序结果中百分含量最高的是五肽,达到24.09%。本研究结果为螺旋藻蛋白资源的进一步开发和利用提供了依据。     

银杏GGPPS转运肽与GFP融合基因表达载体的构建（摘要）

[目的]构建银杏GGPPS转运肽与GFP融合基因表达载体。[方法]以银杏为材料,采用DNA重组技术克隆GGPPS基因质体转运肽（TP）序列,并将其与高效植物表达载体p1304＋连接形成融合表达载体（p1304＋-TP）;冻融法转化根瘤农杆菌EHA105,构建工程菌（EHA105-p1304＋-TP）。[结果]成功构建了银杏GGPPS转运肽与GFP融合基因表达载体及农杆菌工程菌。[结论]为进一步研究TP转运肽的亚细胞定位奠定基础,有助于阐明银杏内酯前体生物合成关键步骤的分子机理,同时为银杏内酯的代谢工程研究提供重要依据。     

论科学发展观与中国城镇化建设

当前我国社会主义新农村的规划与建设存在一些问题,如何根据科学发展观来推进农村小城镇化,正确处理新农村、小城镇规划编制所面对的问题,避免失误,从而完善社会主义新农村的规划建设,无疑具有一定的现实意义。     

桔小实蝇抗菌肽Bactrocerin-2的分离纯化与鉴定

采用阳离子交换层析、RP-FPLC及RP-HPLC分离纯化技术,从细菌诱导的桔小实蝇蛹中分离鉴定出桔小实蝇抗菌肽Bactrocerin-1的同系物Bactrocerin-2。结果表明：Bactrocerin-2含有20个氨基酸残基,分子量为2 311.51 u,序列为VTKTWIKVIRGIGKSKIKWA;并且Bactrocerin-2与Bactrocerin-1的相似性极高,氨基酸同源性达到90％;该肽与鞘翅目Coleoptericin C-末端的20个氨基酸也具有较高的相似性。氨基酸组成分析结果表明,该肽是一种疏水、带正电荷的抗菌肽。该研究将有助于对昆虫天然免疫反应的认知,并为设计有效的抗菌分子奠定基础。     

天津稻区水稻条纹叶枯病发生动态与综合防治

2001~2006年对天津地区水稻条纹叶枯病的上升原因及灰飞虱发生动态进行了调查研究,并对水稻条纹叶枯病的综合防治进行了探讨。研究表明,冬季出现暖冬,春季和秋季雨水偏少,灰飞虱越冬基数增加,春季繁殖系数增大,虫口密度逐年上升是水稻条纹叶枯病上升的主要原因。通过选用抗病品种,调整播种期和插秧期,结合药剂防治,可控制病害的发生程度     

Evaluation of a radioimmunoassay for type III procollagen peptide in the dog

Type III procollagen peptide (P-3-P) is a serum marker for hepatic fibrosis in humans. The utility of a commercially available radioimmunoassay for P-3-P was evaluated in the dog. The specificity of the assay was assessed by polyacrylamide gel electrophoresis (PAGE) of canine serum and purified bovine P-3-P, followed by Western immunoblotting with rabbit aniti-P-3-P serum. The sensitivity was assessed by performing the radioimmunoassay on dilutions of sera from 22 dogs. Polyacrylamide gel electrophoresis of purified bovine P-3-P and sera from two dogs suspected of having elevated P-3-P concentrations revealed no homologous bands of staining. Western immunoblotting showed marked cross-reactivity of the high antisera concentrations with several components of the serum proteins, but none corresponding to the purified P-3-P. All tested sera from dogs had minimal competitive binding with radiolabeled P-3-P in the radioimmunoassay. Dilution curves of dog sera did not parallel either the standard curve or the dilution curve of a known test human serum. There were no statistically different P-3-P concentrations in any of the groups of dogs studied. It was concluded that currently available radioimmunoassay kits for the measurement of P-3-P in the human are not applicable in the dog. Seemingly, the structure or metabolism of canine P-3-P may vary significantly from that of the bovine or human, limiting the sensitivity and specificity of this assay in the dog.     

水稻条纹病毒在玉米和水稻上流行差异分析

为了明确水稻条纹病毒(RSV)在水稻和玉米上发生程度差异明显的原因,从一个侧面了解RSV流行本质,2004年在洪泽进行田间试验。采用黄盘诱集、盘扑、盘刮、肉眼计数等方法比较武育粳3号和掖单13上灰飞虱侵入和消长动态,结果表明两者均只有一个成虫侵入高峰,单位面积迁入虫量前者是后者的3.6倍,单株平均虫量相近。Dot-ELISA法测定灰飞虱带毒率为40%,成虫迁移扩散高峰期22d内两者接毒量约为每天百株137头带毒虫。武育粳3号有二代若虫发生,掖单13则无。逐日调查发病进程,结果显示水稻发病率为60%,玉米为0。室内抗性鉴定,掖单13对RSV的抗性比武育粳3号高4个级别。综合以上结果,寄主品种抗性决定了RSV在水稻和玉米上流行状况,二代若虫重复侵染是RSV在水稻上重发的另一主要原因。     

高能湿法球磨制备鱼胶原肽螯合钙及其理化特征

为了拓展胶原肽螯合钙的制备工艺,以鱼胶原肽和CaCl2为原料,以高能湿法球磨的方法制备了鱼胶原肽螯合钙,并采用FT-IR红外图谱、X-衍射、EDS能谱等技术手段对其理化特性和结构进行分析.结果显示,随着球磨时间从15 min延长到240 min,鱼胶原肽的平均粒径逐渐降低,ZETA电位绝对值、分子量和pH值逐渐增加,鱼...     

Comparison of N-terminal pro-atrial natriuretic peptide and three cardiac biomarkers for discriminatory ability of clinical stage in dogs with myxomatous mitral valve disease

Plasma N-terminal pro-atrial natriuretic peptide (NT-proANP) concentration increases with progression of myxomatous mitral valve disease (MMVD) in dogs. This multicentre, prospective study compared plasma NT-proANP, N-terminal pro-brain natriuretic peptide (NT-proBNP), ANP, and cardiac troponin I (cTnI) concentrations in dogs with MMVD for their characteristics and discriminatory ability to detect cardiac dilatation and congestive heart failure (CHF). Thirty-six healthy dogs and 69 dogs with MMVD were included. Clinical variables were obtained via physical examination, thoracic radiography, and echocardiography. The discriminatory ability of each cardiac biomarker (CB) to determine the presence or absence of cardiac dilatation (event 1) and CHF (event 2) was evaluated using the receiver operating characteristic curves. Plasma NT-proANP, NT-proBNP, and ANP concentrations showed a significant association with the left atrium/aorta ratio (P<0.01). The area under the curve of plasma NT-proANP and NT-proBNP concentrations were 0.72 and 0.75, respectively in event1 and 0.72 and 0.76, respectively in event2. Plasma NT-proANP and NT-proBNP concentrations showed sensitivity 80.0 and 80.0%; specificity 67.6 and 64.7% in event1 (cutoff value; 8,497.81 pg/ml and 1,453.00 pmol/l, respectively) and sensitivity 85.7 and 81.0%; specificity 60.4 and 64.6% in event2 (cutoff value; 8,684.33 pg/ml and 1,772.00 pmol/l, respectively). In dogs with MMVD, plasma NT-proANP, NT-proBNP, and ANP concentrations increase with left atrial enlargement. Particularly, plasma NT-proANP and NT-proBNP concentrations appeared to be equally useful in the discriminatory ability to detect cardiac dilatation and CHF.     

Immunohistochemical analysis of pseudorabies virus spread through neurons innervating the eyeball

Pseudorabies virus (PRV) was inoculated intraocularly into BALB/c mice, and the distribution pattern of cells positive for several neurotransmitters and viral antigens in the eyeball, trigeminal nerve ganglia, and superior cervical ganglia was examined immunohistochemically to clarify the neural route of the virus spread. In the eyeball, substance P (SP)- and calcitonin gene-related peptide (CGRP)-positive cells were detected in the ipsilateral iris and ciliary body, neuropeptide tyrosine (NPY)-positive cells were detected in the choloid membrane, and tyrosine hydroxylase (TH)-positive cells were detected in the ipsilateral inner nuclear layer of the retina; all these cells contained viral antigens. In the superior cervical ganglia, viral antigen-positive cells containing TH or NPY were found at bilateral sites. In the trigeminal nerve ganglia, viral antigen-positive cells containing SP or CGRP were found at bilateral sites. These findings indicated that the SP- and CGRP-positive ganglion cells of the trigeminal nerve ganglia innervating the iris or ciliary body, and the NPY-positive ganglion cells of the superior cervical ganglia innervating the iris, ciliary body, and choroid membrane served as the route for the virus spread. These findings also suggested that dopaminergic neurons, such as the TH-positive retinal cells and TH-positive ganglion cells of the superior cervical ganglia, served as the route for virus spread.