Development of a multiplex polymerase chain reaction for the simultaneous detection of microsporidians, nucleopolyhedrovirus, and densovirus infecting silkworms

We have developed a novel PCR-based assay for individual and simultaneous detection of three major pathogens (microsporidians, nucleopolyhedrovirus (NPV) and densovirus (DNV)) infecting the silkworm, Bombyx mori. Multiplex PCR, using three primer pairs, two of which were designed from the conserved regions of 16S small subunit ribosomal RNA gene of microsporidians, and polyhedrin gene of NPVs respectively, and a third primer pair designed from the internal sequences of B. mori DNVs (BmDNV), showed discrete and pathogen specific PCR products. The assay showed high specificity and sensitivity for the pathogenic DNA. Under optimized PCR conditions, the assay yielded a 794 bp DNA fragment from Nosema bombycis, 471 bp fragment from B. mori NPV (BmNPV) and 391 bp fragment from BmDNV. Further, this detection method was successfully applied to other silkworm species such as Antheraea mylitta and Samia cynthia ricini, in detecting same or similar pathogens infecting them. This method is a valuable supplement to the conventional microscopic diagnostic methods and can be used for the early detection of pathogens infecting silkworms. Furthermore it can assist research and extension centers for the safe supply of disease-free silkworms to farmers.     

人类新基因WDR70的克隆及初步研究

运用基于基因组数据库的特定基因同源新基因的克隆策略得到一个人类新基因WDR70 ,该基因编码一个包含 12个WD4 0结构域的蛋白。WDR70的cDNA序列长 2 2 6 6bp ,预测编码蛋白含 6 30个氨基酸 ,理论分子量为 70× 10 3 u ,染色体定位为 17p13.1。以小鼠胚胎为模型进行整体原位杂交 ,结果显示WDR70基因在 8.5d小鼠胚胎中没有表达 ,而在 9.5d和 10 .5d的小鼠胚胎的脑部有特异表达。由此推断该基因对胚胎期脑部的发育有重要的影响。     

基于样带的唐古特白刺灌丛沙包空间格局尺度研究

黄河河岸与库布齐沙漠之间生态过渡带上的唐古特白刺(Nitraria Tangutorum)灌丛沙包由于遭受到不同程度的破坏而表现出一定程度的退化,空间格局尺度从一定程度上表征了其破碎化程度。我们分别应用样方方差法,小波分析,分维,谱分析以及空隙度分析等方法对鄂尔多斯高原北缘唐古特白刺灌丛沙包的空间格局尺度进行了比较研究,旨在选出适合分析干旱半干旱区白刺灌丛沙包空间格局尺度的方法,并确定研究区内唐古特白刺灌丛沙包的空间格局尺度,为保护唐古特白刺灌丛沙包提供科学依据。结果表明:(1)TTLQV法得到的格局尺度过大,而小波分析得到的格局尺度过小,分维分析得到的格局尺度除了相对较小之外,趋势也不明显,因此都不适合分析干旱半干旱区白刺灌丛沙包的空间格局尺度;(2)而3TLQV,tQV,谱分析和空隙度分析所得到的结果则相对容易接受,其大小顺序是:3TLQV>tQV>空隙度分析>谱分析;(3)独贵塔拉、呼和木独和巴拉贡唐古特白刺灌丛沙包的空间格局尺度分别为16.7～27.1m,10.2～25.0m和8.8～17.0m,这一结果将有助于在今后的研究中合理地确定研究范围和尺度。     

Fractal dimension in aspiration cytology smears of breast and cervical lesions

OBJECTIVE: To standardize the automated measurement of fractal dimension on cytologic smears and compare the fractal dimension of benign and malignant breast cells and cervical lesions on cytologic material to evaluate its role in the discrimination of benign from malignant cells. STUDY DESIGN: We randomly selected fine needle aspiration cytology smears of 42 cases of infiltrating duct carcinoma and 38 cases of fibroadenoma of the breast. Similarly, 16 cervical carcinoma and 20 normal cervical smears were selected for study. Ten cells were selected randomly from each case. Box counting of fractal dimension of malignant and benign cells was achieved with an image cytometer (Leica, Cambridge, England) using Quantimet 600 software (Leica). Then a well-spaced grid with multiple small boxes of a particular pixel length was superimposed on the cell. The dimension of the box was selected as 4, 8 and 16 pixels. With the help of a logical "AND" operation, we counted the number of boxes touching the peripheral margin of the cell nuclei. For each cell, the log-log graph of 1 per box size was plotted against the number of boxes touching the peripheral rim of the cell. The slope of each graph was identified using the least-squares method of regression analysis. RESULTS: The mean fractal dimension of malignant cells was 0.8536 +/- 0.1120 as compared to 0.8403 +/- 0.1115 in benign cell groups. The Mann-Whitney U test showed a significant difference in fractal dimension in these 2 groups (P = .05). The mean fractal dimension of malignant cells from the cervix was 0.8656 +/- 0.1499 as compared to 0.8315 +/- 0.1312 in benign cells. The Mann-Whitney U test showed a significant difference in fractal dimension in these 2 groups (P < .02). CONCLUSION: Fractal dimension may be a helpful adjunctive technique to discriminate between benign and malignant cells.     

小麦叶片β-1,3-葡聚糖酶的诱导、纯化与抗菌活性

三个小麦品种331、抗倒680和鲁麦23经氯化汞、水杨酸或核黄素处理后,叶片中的β-1,3-葡聚糖酶活性均有不同程度的升高.氯化汞处理24h对品种331该酶活性的诱导作用最强.因此取用氯化汞处理24 h的331小麦叶片研磨得到粗酶液.将粗酶液经硫酸铵分级沉淀、Phenyl-Sepharose Fast Flow疏水层析、DEAE-Sepharose Fast Flow阴离子交换层析和Sephacryl S-100分子筛层析,得到了SDS-PAGE凝胶电泳谱带单一的β-1,3-葡聚糖酶样品.经SDS-PAGE(12%)和凝胶过滤层析,测得其分子量约为52.0～53.6 kD.抗菌试验测定显示,纯化的β-1,3-葡聚糖酶对供试的4种病原真菌的生长、孢子萌发或芽管伸长都有一定程度的抑制作用.     

心衰患者动脉血气波浪式变化及其幅度降低的初步实验证据*

目的: 心力衰竭患者呼吸调控异常的机制众说纷纭,特别是动脉血气周期性波浪式变化信号的改变及其与心功能的关系尚缺乏直接的试验证据。本文依据心力衰竭患者动脉血气周期性波浪式变化信号的降低幅度,探讨心力衰竭导致呼吸调控异常的机制。方法: 选择5名心力衰竭患者,连续桡动脉逐搏取血,测定PaO₂,PaCO₂,pHa和SaO₂。选取2个典型呼吸周期,用于分析动脉血气的波浪式变化。比较患者相邻最高和最低值,以验证是否存在周期性波浪式信号变化。此外,将心力衰竭患者与心功能正常患者动脉血气周期性波浪式信号的变化幅度进行统计学t检验分析,比较有无差异。结果: 心力衰竭患者包括2例外科手术和3例ICU住院监护患者,4男1女,年龄(69±7)岁,身高(169±10)cm,体质量(75±19)kg,左心射血分数(LVEF)=(38±3)%。动脉血液充满肝素化细长塑化管需要17±2次心跳,即取血需要17±2次心跳,覆盖超过2个呼吸周期。心力衰竭患者PaO₂,PaCO₂,[H⁺]a和SaO₂均呈现明显的波浪式变化(P<0.05),幅度分别是(7.94±2.02)mmHg,(1.18±0.56)mmHg,(0.54±0.17)nmol/L和(0.21±0.07)%,分别是各自均值的(6.1±1.5)%,(3.2±1.5)%,(1.5±0.5)%和(0.2±0.1)%。与心功能正常患者比较,动脉血气波浪式变化幅度呈现明显降低趋势,但仅PaO₂和[H⁺]a有明显统计学差异(P<0.05)。结论: 采用连续逐搏动脉取血血气分析法证实,心力衰竭患者自主呼吸时动脉血气也有周期性波浪式变化信号,但其变化幅度较心功能正常患者明显降低。     

Discovery and evaluation of novel FAAH inhibitors in neuropathic pain model

Conceptual design and modification of urea moiety in chemotype PF-3845/04457845, the bench marking irreversible inhibitor of fatty acid amide hydrolase (FAAH), led to discovery of a novel nicotinamide-based lead 12a having reversible mechanism of action. Focused SAR around the pyridine heterocycle (Ar) in 12a (Tables 1 and 2) resulted into four shortlisted compounds, (?)-12a, (?)-12i, (?)-12l–m. The required (?)-enantiomers were obtained via diastereomeric resolution of a novel chiral dissymmetric intermediate 15. Based on comparative profile of FAAH potency, metabolic stability in liver microsome, liability of inhibiting major hCYP450 isoforms, rat PK, and brain penetration ability, two SAR optimized compounds, (?)-12l and (?)-12m, were selected for efficacy study in rat model of chemotherapy-induced peripheral neuropathy (CIPN). Both the compounds exhibited dose related antihyperalgesic effects, when treated with 3–30?mg/kg po for 7?days. The effects at 30?mg/kg are comparable to that of PF-04457845 (10?mg/kg) and Tramadol (40?mg/kg).     

Exclusion effects on vegetation characteristics and their correlation to soil factors in the semi-arid rangeland of Mu Us Sandland,China

Exclusion has been applied as a main measure for re-vegetation all over the world.This paper,by comparing the results of year-round exclusion,seasonal exclusion,and non-exclusion,quantified the vegetation variations under three different exclusion measures and their correlation to soil factors.The analysis results for community species component and plant diversity using multi-response permutation procedures (MRPPs)showed that exclusion did change the species component and increase plant diversity remarkably,while the period of exclusion had no significant influence on these two community features.The indicator species analysis and calculation of similarity indices indicated that community for year-round exclusion were becoming xerophytization and unpalatability,and showed highly spatial heterogeneity of plant species distribution,whereas community for seasonal exclusion was under stable non-equilibrium condition.Detrended correspondence analysis (DCA)and detrend canonical correspondence analysis (DCCA)results of relationship between plant species and soil variables demonstrated that soil moisture was a controlling factor for plant species component,microbiotic soil crust cover,soil organic matter,and soil bulk density had significant effects on soil moisture,among which microbiotic soil crust was a leading factor owing to its limitation to rainfall infiltration on the one hand,and its constraints to entrance of herbaceous seeds into soil or to germination of soil seeds on the other hand.As a result of long-term removal of animal grazing,crust kept intact in year-round exclusion community,which was a main reason of community xerophytization.It was also obvious from ordination results that some important environmental factors,such as tempo-spatial change of rainfall and corresponding tempo-spatial change of soil moisture,were neglected during direct gradient analysis.In addition,biodiversity was close related to soil nutrients as well as to soil moisture condition (soil water content and crust cover),and it had positive relation to available N,and negative relation to available P.Higher soil N had advantage to non-leguminous plants growth on nutrition-poor sand land definitely.The impact of P to community component was unclear and should be studied from plant physiology.Further researches on nonequilibrium theory in semi-arid rangeland will provide a scientific and flexible animal development paradigm for being implementing livestock fen-raising and grazing-forbidden policies in China.     

防治荒漠化的“三圈”生态-生产范式机理及其功能

防治荒漠化的“三圈”生态-生产范式,是干旱生态系统优化与重建的新结构。根据在鄂尔多斯和新疆等地的研究和实践,从干旱生态系统结构、过程和功能来讨论荒漠化防治的“三圈”范式。地理圈层结构（地理地带性）是“三圈”范式的自然地理背景。从宏观尺度和功能方面划分,“三圈”范式在空间尺度上有大“三圈”和小“三圈”之分,大“三圈”控制洲际范围的荒漠化扩展及沙尘暴蔓延,小“三圈”则以控制区域性风沙活动、沙尘暴和就地起沙的危害。防治荒漠化工程是复杂的多元组合和多功能的系统,我国西北地区受荒漠化影响严重,宏观的大“三圈”与多区域的小“三圈”有机结合,形成圈圈相护、层层设防的严密防护与生产系统,有效地控制大范围风沙危害、改善地方气候与小气候,并对发展经济,提高人民生活发挥重要作用。因此,“三圈”范式的概念与结构既是以自然地理地带性为基础,又是人类对自然、环境与生态系统格局的规律认识,更是科学的人类恢复、重建干旱区生态环境与可持续发展的生态设计范式。