基于谱域相干的细胞动态检测技术

将谱域光学相干层析技术（Spectral-domain Optical Coherence Tomography,SD-OCT）应用于细胞膜厚的动态检测,引入了光谱干涉测量方法,通过对干涉光谱信号进行离散傅里叶变换得到表示物体深度位置信息的光程差信号。搭建了一套SD-OCT测量系统并设计了专门用于细胞检测的样品平台,检测精度达到μm量级,信噪比达70 db,是一种快速、实时、非接触的细胞分子膜厚动态检测技术。     

粗毛栓菌和蜡状芽孢杆菌及其共固定菌对pb2+的吸附

将粗毛栓菌菌丝球与蜡状芽孢杆菌共固定为共固定菌.以粗毛栓菌菌丝球、蜡状芽孢杆菌和共固定菌为研究对象,测定不同吸附时间、初始pH、吸附剂浓度和pb2+浓度对3种生物吸附剂吸附pb2+的影响,并将3种生物吸附剂吸附pb2+前后的红外吸收光谱进行分析比较.结果表明:在吸附剂浓度为2g.L-1、pH为5.0、pb2+浓度为50 mg·L-1条件下对pb2+吸附lh效果良好,其吸附率分别为71.7％、91.0％和96.9％.生物吸附剂红外光谱主要由蛋白质、碳水化合物和含硫、磷酸基团的吸收带组成,表明对pb2+吸附起主要作用的官能团是羟基、羧基、磷酸基和含硫基团.     

缙云山常绿阔叶林不同演替阶段植物生活型谱比较研究

采用Raunkiner生活型分类系统,对缙云山常绿阔叶林不同演替阶段植物的生活型进行统计,编制了生活型谱,并与其他亚热带地区常绿阔叶林相比较。结果表明,缙云山植被属典型的中亚热带常绿阔叶林植被,高位芽植物占绝对优势,达80％以上,其中小高位芽植物最多,中高位芽与矮高位芽植物次之,藤本植物较丰富。缙云山不同演替阶段的植物的生活型谱不同。随着进展演替阶段的逐渐更替,高位芽植物的比例呈递增趋势,地面芽植物、地下芽植物成分有所减少。高位芽的常绿树种会逐渐代替针叶树种。     

Membrane-potential- and surface-potential-induced absorbance changes of merocyanine dyes added to chromatophores from Rhodopseudomonas sphaeroides

(1) Three analogs of merocyanine dyes added to suspensions of chromatophore vesicles showed absorbance changes responding to the change in surface potential induced by salt addition and to the change in membrane potential induced by illumination. (2) The extent of the light-induced absorbance changes of the dyes was linearly related, in the presence and absence of uncouplers, to that of carotenoid spectral shift which is an intrinsic probe of the intramembrane electric field. (3) Comparison of the merocyanine absorbance changes induced by salt addition with those induced by illumination indicated that the surface potential change in the outer surface of chromatophore membranes during illumination was very small. (4) Judging from the spectra of these absorbance and from the low permeabilities of the dyes to membrane, the absorbance change are attributed to change in distribution of the dyes between the medium and the outer surface region in chromatophore membranes. The extent of the light-induced absorbance changes of merocyanine dyes depended on the salt concentration of the medium. The types of dependence were different among three merocyanine analogs. This is explained by the mechanism mentioned above assuming appropriate parameters. It is suggested that, under continuous illumination, an equilibrium of the electrochemical potential of H⁺ is reached between the bulk aqueous phase and the outer surface region in the membrane where the merocyanine dyes are distributed.     

Induction and characterization of pigmentation mutants in Porphyra yezoensis (Bangiales, Rhodophyta)

Porphyra yezoensis Ueda conchospore germlings (1–4-cell stages) were treated with N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) for inducing mutations. Three kinds of color-mutated gametophytic blades, which were composed of the mutated cells wholly, sectorially or spottedly, were obtained; and most of them were sectorially variegated blades. The highest frequency of these mutated blades was 1.3%. Four different pigmentation mutant strains were obtained by regenerating single cells and protoplasts that were enzymatically isolated from the mutated sectors of the sectorially variegated blades. The mutants were relatively stable in color in both gametophytic blade and conchocelis phases. In the two phases, each mutant strain showed characteristic differences in the in vivo absorption spectra, and had different pigment contents of major photosynthetic pigments (chlorophyll a, phycoerythrin and phycocyanin) as compared with the wild-type and with each other. The gametophytic blades from the four mutant lines showed significant differences in growth and photosynthetic rates, when they were cultured in the same conditions. By crossing the mutant with the wild-type, it was found that the color phenotypes of two mutants reported above, were resulted from two mutations in different genes, respectively. This revised version was published online in August 2006 with corrections to the Cover Date.     

Physical, chemical and spectral properties of leaf surfaces of Berberis aquifolium (Pursh.)

Abstract The leaves of Berberis aquifolium (Pursh.) exhibit either diffuse or specular (shiny) reflection, depending on the variety, but in no case are the leaves obviously glaucous. The dull-surfaced leaves were less wettable than the glossy ones. Using scanning electron microscopy it was determined that the diffuse reflection was due to tubular crystals of wax 250 nm in diameter. The crystals were primarily composed of 19-nonacosanol, a 29-carbon secondary alcohol, as determined by gas chromatography-mass spectrometry. The chemical constituents of the wax underlying the tubes appeared to be the same as those of the wax from glossy leaves, with 29-carbon and 31-carbon n-alkanes and n-heptacosanol as major constituents. The reflection spectra of dull-surfaced (diffuse reflection) or glossy (specular reflection) leaves were the same, as were those of leaves with different amounts of epicuticular wax. Removing the epicuticular wax with chloroform did not change the spectrum.     

Action spectra of phototactic responses of the flea beetle, Phyllotreta striolata

Abstract.  Adult flea beetles, Phyllotreta striolata , show a strong positive phototactic response. The action spectrum of phototaxis of dark-adapted beetles was measured with minimal required light intensity between the wavelength range of 300 nm and 600 nm. Male and female flea beetles showed identical phototacitc behaviours. The beetles were most sensitive to light with peak wavelengths between 350 nm and 430 nm in the morning. In the afternoon and evening, the sensitivity to wavelengths shorter than 430 nm decreased, but they remained most sensitive to 430 nm. These results suggest that changes in sensitivity of the photoreceptors or nervous integration influence the phototactic responses, and that the blue wavelengths are more attractive than others.     

Classification of life cycle form spectrum of artificial community of Pinus svlvestris var. mongolica

The plant life cycle form and its spectrum features of different plants in the artificial community of Pinus svlvestris var. mongolica at the botanical garden of Northeast Forestry University were classified by PCA method. For canopy layer plants, the vegetative growth (V) accounted for 46%, the sexual growth (S) accounted for 35%, and the clonal growth (C) accounted for the rest 19%. For succession layer plants, V accounted for more than 50%, and C accounted for a little higher than S did. For herbaceous layer plants, V accounted for nearly 47%, which was only 4% higher than that of S, and C only accounted for 11%. These findings indicate that the plant life cycle forms of canopy layer plants and herbaceous layer plants were VS transition form with V form as the main form, while the succession layer plants were V form. At the viewpoint of artificial community, the life cycle form can be described as V_0.49S_0.33C_0.18, a typical VS transition form, indicating that most of the species studied in this community are in a healthy status with the V form. Moreover, the relatively high (33%) percentage in the S form indicates that the community also tends to sexual growth for offspring, although it will be steady within a period of time for the vegetative growth of bodies.     

应用化学基因组信息预测小分子化合物的潜在生物靶标的理论方法

在后基因组时代,化学基因组技术在药物作用靶点的确认、小分子化合物对通路的作用,以及小分子先导化合物的识别等方面都有着广泛的应用,为新药研发提供了新的技术方法。本文主要介绍了当前几种基于化学基因组信息来预测小分子化合物潜在生物靶标的理论方法（包括化学相似性搜索方法、反向分子对接方法、数据挖掘方法以及生物活性谱图分析方法）,并分析了这些方法的优缺点以及应用前景。     

儿科产超广谱β-内酰胺酶肺炎克雷伯菌感染现状及耐药性分析

目的研究吉林市2005年1月至2007年12月期间儿科产超广谱β－内酰胺酶（extended speetrurn β－lactamases,ESBLs）肺炎克雷伯菌感染现状及耐药性。方法按照CLSI／NCCLS2005年标准筛选确认ESBLs表型,采用琼脂纸片扩散法进行药敏试验。结果ESBLs总检出率为56．3％,3年检出率分别为2005年33．3％、2006年47．1％和2007年为57．1％。产ESBLs菌株全部表现为多重耐药,对氨苄西林、哌拉西林、头孢呋辛和头孢唑啉的耐药率达100％,对阿米卡星、头孢吡肟、头孢他啶和哌拉西林／他唑巴坦的耐药率低于50％,对头孢噻肟、头孢曲松和氨曲南的耐药率逐年上升,发现对亚胺培南耐药菌株。结论吉林市儿科产ESBLs肺炎克雷伯菌检出率较高,临床治疗中应重视产ESBLs菌的监测,并动态监测其耐药性变迁,防止ESBLs肺炎克雷伯菌的传播。