Hematopoietic chimerism monitoring based on STRs: quantitative platform performance on sequential samples.

Hematopoietic stem cell transplantation (HSCT) creates a donor-recipient cellular chimerism in the patient, which is quantitatively assayed from peripheral blood based on STR-DNA. Since chimerism values often vary across a patient's samples, it is important to determine to what extent this variability reflects technical aspects of platform performance. This issue is systematically assessed in the current study for the first time. Using the SGM Plus multiplex PCR kit and ABI platform, the longitudinal performance of STR markers was quantitatively evaluated in two chimeric models with true values, and in patient samples (n >500 marker loci). Computation of percent chimerism for each marker, and mean (sample) percent chimerism, standard deviation, and coefficient of variance was performed by our ChimerTrack utility. In chimeric models with known values, individual markers exhibited an accuracy (observed/true) of 88-98%; replication precision was 92-100% true, with a mean error of 2%. Fragment size calling was greater than 99% accurate and precise. Patient results were comparable for markers, relaive to sample means. One source of technical variability in chimerism estimation was allelic differential amplification efficiency. The latter was influenced by signal amplitude, dye label, marker size, and allelic size interval. It can be concluded that long-term chimeric tracking is routinely feasible using this platform in conjunction with ChimerTrack software. Importantly, mean percent chimerism, for any sample, should closely approximate the true chimeric status, with a technical accuracy of 98%. Guidelines are presented for selecting an optimized marker profile.     

Screening the Main Factors Affecting Extraction of the Antimicrobial Substance from Bacillus sp. fmbJ using the Plackett–Burman Method

Summary The Plackett–Burman screening method was utilized as a tool to evaluate the importance of the selected six factors, including methanol, ethanol, propanol, butanol, pH and time, which are relevant to the extraction of the antimicrobial substance produced by Bacillus sp. fmbJ. The main factors that affected the extraction of the antimicrobial substance were determined as methanol (P < 0.0001), ethanol (P < 0.0001), pH (P = 0.0032), and time (P < 0.0001) by using the JMP software. Within the test ranges, methanol, ethanol, and time showed a significant positive relativity to the total extracted amounts respectively; while pH had a significant negative effect. The maximum prediction profile indicated that the total extracted amounts for the antimicrobial substance would reach 50.21 mg/100 ml with 99.64% probability.     

无芒雀麦种子产量因子与产量的相关和通径分析

采用多因素正交试验设计,通过大样本相关、通径和逐步回归分析后表明,无芒雀麦5个种子产量因子对种子产量的直接贡献大小排序为:生殖枝数/m 2＞种子粒数/小穗＞小花数/小穗＞单粒种子重＞小穗数/生殖枝;提高小花数/小穗和种子粒数/小穗可最有效提高无芒雀麦的种子产量,其次是提高生殖枝数/m2.     

美国不同棱型大麦种质资源品质分析

对新引进的300份美国大麦种质资源不同棱型间蛋白质、赖氨酸和淀粉含量的鉴定结果分析表明:①二棱大麦蛋白质总体方差与六棱大麦具有极显著的差异,其频率分布分别是以含量12.5%和17.0%为中心的双峰分布,这可能反映了二棱大麦利用上的新特点;淀粉含量二棱大麦显著高于六棱;六棱大麦当蛋白质作为固定变量时,赖氨酸与淀粉的相关性不显著.②提出了促进SPSS统计分析软件在农业科研上的开发应用研究的建议.     

Visual BASIC编程在核酸序列分析中的应用研究初探

利用可视化的编程语言VisualBASIC编写了一个简易实用的核酸序列分析程序 ,能够自动实现对已知核酸序列的分子质量、Tm值、碱基组成的测定、各种核酸序列的转换和氨基酸序列的推导。同时也详细描述了核酸序列自动分析各功能实现的VisualBASIC语言编程过程。     

播栽期对水稻产量和产量构成因素及生育期的影响

研究了不同播栽期对水稻产量和产量构成因素及生育期的影响。结果表明 ,随播栽期推迟 ,水稻产量有所降低。每穗成粒数减少是推迟播栽期引起水稻减产的主要原因 ,其次是千粒重的下降和成穗数的降低。针对目前的生产实际 ,提出了一些应对播栽期推迟的技术措施。     

遗传学实验显微图像采集与演示系统设计

利用 Microsoft® Visual Basic 6.0 设计开发了“遗传学实验显微图像采集与演示系统”,该系统主要包括图像采集和编辑、文本输入和编辑,实验指导和图像演示、图像检索和数据库管理、系统维护及帮助等功能,各部分都以窗口形式设计,既可采用视频图像采集卡实时捕获图像,又可通过扫描仪、数码相机、剪贴板或文件输入已有的图像,并经压缩技术处理后与文字说明、实验指导一同存入数据库,方便、快捷、灵活地实现了对图像的输入和编辑、查询和演示,无论是对教师的遗传学实验教学,还是对学生的遗传学实验的自学,都起到了良好的辅助作用。Abstract: A system for capturing and showing micrographs of genetics was designed with Microsoft® Visual Basic 6.0. The system includes many functions such as capturing and editing images, typing and editing text, teaching experiments, showing images, image retrieval, database management, system maintenance and help, all of them were developed with the form of windows. The system could collect images not only from image-grabber card in real-time but also from scanner, digital camera, clipboard and files. After utilizing the image compression technology, the images will be saved in database along with experiment instruction. With all the features referred above, the system can used as a wonderful assistant both for the teaching of genetics experiment and for the students’ learning by themselves.     

Relationships between soil bulk electrical conductivity and the principal component analysis of topography and soil fertility values

Measures of soil electrical conductivity (EC) and elevation are relatively inexpensive to collect and result in dense data sets which allow for mapping with limited interpolation. Conversely, soil fertility information is expensive to collect so that relatively few samples are taken and mapping requires extensive interpolation with large estimation errors, resulting in limited usefulness for site-specific applications in precision agriculture. Principal component (PC) analysis and cokriging can be applied to create meaningful field scale summaries of groups of attributes and to decrease the estimation error of maps of the summarized attributes. Deep (0–90 cm) and shallow (0–30 cm) EC, elevation, and soil fertility attributes were measured in fields under corn (Zea mays L.) and soybean (Glycine max L.) rotations, at two sites in Illinois (IL) and two sites in Missouri (MO). Soil fertility and topography attributes were summarized by PC analysis. The first topography PC (TopoPC1) contrasted flow accumulation against elevation and curvature, to describe the main topographic pattern of the fields. The first soil fertility PC (SoilPC1) consistently grouped together cation exchange capacity (CEC), Ca, Mg, and organic matter (OM). SoilPC1 was well correlated to soil EC for all sites and cokriging with EC had higher r ² in the crossvariogram models compared to ordinary kriging. The second and third soil fertility PCs (SoilPC2 and SoilPC3) were concerned with soil pH and P, and reflected historic land use patterns. Maps of SoilPC2 and SoilPC3 had little relationship to soil EC or topography and so could not be improved by cokriging.     

Spatial variation and effects of habitat on temperate reef fish assemblages in northeastern New Zealand

Reef-associated fishes can respond to changes in habitat structure and the nature of their response can change with different spatial scales of observation. A structured hierarchical mensurative sampling design was used to sample temperate reef fish assemblages in northeastern New Zealand at several spatial scales over 2 years. The three spatial scales examined were tens of meters (transects), hundreds to thousands of meters (sites) and hundreds of kilometers (locations). We tested the hypothesis that fish assemblages differed between kelp forest habitat (relatively dense stands of the kelp, Ecklonia radiata (C. Agardh) J. Agardh, median depth=13.5 m) and barrens habitat (rocky reef dominated by turfing and encrusting red algae and the grazing urchin, Evechinus chloroticus (Valenciennes), median depth=6.7 m). Recently developed multivariate techniques were used to test for and quantify multivariate variation at different spatial scales. There were significant effects of habitat on the spatial distribution of fish assemblages, characterised by greater abundances or frequencies of Parika scaber, Chromis dispilus, Trachurus novaezelandiae, Nemadactylus douglasii, Bodianus unimaculatus, Odax pullus and Pseudolabrus miles in kelp forest habitat, and greater abundances or frequencies of Notolabrus celidotus, Notolabrus fucicola, Girella tricuspidata, Coris sandageri, Chironemus marmoratus, Parma alboscapularis, Scorpis violaceus and Kyphosus sydneyanus in barrens habitat. Some of the more common species, including Upeneichthys lineatus, Scorpis lineolatus and Cheilodactylus spectabilis showed no strong consistent effects of these two differing habitats on their distributions. There was, however, a significant Habitat×Locations interaction: effects of habitat did not occur at all locations. Variability was highest at the scale of individual transects and variability from site to site and from location to location was comparable. Spatial variation was large compared to inter-annual variation, which was minimal, and spatial patterns were consistent in the 2 years examined. Further experiments, including manipulations, are required to understand what mechanisms and processes might be driving these patterns. This study, coupled with results from previous studies, suggests that there may be a dynamic inter-play between effects of habitat on fish and effects of fish on biogenic habitat, such as kelp forests.     

大叶钩藤中非生物碱成分对骨肉瘤细胞增殖的影响

大叶钩藤 (ＵｎｃａｒｉａｍａｃｒｏｐｈｙｌｌａＷａｌｌ.)系茜草科钩藤属植物 ,为常用中药 ,用于治疗头晕目眩、惊痫抽搐、全身麻木等疾病。现已成为治疗高血压方剂中的常用药物[1] 。其化学、药理及应用有较多研究 ,但绝大部分是针对生物碱部分 ,非生物碱部分作为无用成分而极少研究和应用。为了明确其药理作用的物质基础及进一步挖掘其药用潜能 ,作者在对大叶钩藤的非生物碱部分进行系统研究的基础上[2 ] ,对抗肿瘤活性进行研究。1　材料与方法1 1　实验材料实验样品乌索酸 (Ⅰ )、3β 6 β 2 3 三羟基乌索酸 (Ⅲ )、表儿茶素 (Ⅳ )、…