Ontogenetic variations in the venom proteome of the Amazonian snake Bothrops atrox

Background  

Bothrops atrox is responsible for the majority of snakebite accidents in the Brazilian Amazon region. Previous studies have demonstrated that the biological and pharmacological activities of B. atrox venom alter with the age of the animal. Here, we present a comparative proteome analysis of B. atrox venom collected from specimens of three different stages of maturation: juveniles, sub-adults and adults.     

Redox-induced transitions in bovine cytochrome bc1 complex studied by perfusion-induced ATR-FTIR spectroscopy

Redox transitions in a film of detergent-purified bovine cytochrome bc(1) complex were investigated by perfusion-induced attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The technique provides a flexible method for generating redox-induced IR changes of components of bovine cytochrome bc(1) complex at a high signal:noise ratio. These IR redox difference spectra arise from perturbations of prosthetic groups and surrounding protein. Visible difference spectra were recorded synchronously using a light beam reflected from the exposed prism surface and provided a quantitative means of determining the redox transitions that were occurring. IR and visible redox difference spectra of iron-sulfur protein/cytochrome c(1), heme b(H), and heme b(L) were separated by selective reduction and/or oxidation that extends published data on the homologous bacterial enzyme. Several bands could be tentatively assigned to redox-sensitive modes of hemes and ubiquinone and changes in the surrounding protein by comparison with available data for bacterial bc(1) complex, other related heme proteins, and model compounds. Some tentative assignments of further signals to specific amino acids are made on the basis of known crystal structures.     

米碎花的酚苷类化合物及其鼻咽癌细胞毒活性

为了解米碎花(Eurya chinensis)的化学成分及其生物活性,运用多种色谱技术从其乙醇提取物分离得到11个化合物,并对化合物进行体外抗鼻咽癌细胞增殖活性评价。经波谱数据分析,分别为异落新妇苷(1)、3,5,7-三羟基色原酮-3-O-α-L-鼠李糖苷(2)、1-O-反式-桂皮酰基-β-D-葡萄糖(3)、1-O-(4-羟基苯乙基)-6-O-反式-桂皮酰基-β-D-葡萄糖(4)、eutigoside D (5)、1-O-(3,4-二羟基苯乙基)-6-O-反式-香豆酰基-β-D-葡萄糖(6)、eutigoside A (7)、1-O-(4-羟基苯乙基)-6-O-反式-咖啡酰基-β-D-葡萄糖(8)、grayanoside A (9)、1-O-(4-羟基苯乙基)-6-O-(4-羟基苯甲酰基)-β-D-葡萄糖(10)、3-O-β-D-葡萄糖基-4-羟基-苄基苯甲酸酯(11)。其中,化合物4为首次从天然来源获得,化合物2～4和8～11均为首次从该属植物中分离得到。MTT法表明,化合物10具有中等抑制5-8F细胞增殖活性。     

The significance of controlled conditions in lentiviral vector titration and in the use of multiplicity of infection (MOI) for predicting gene transfer events

BACKGROUND: Although lentiviral vectors have been widely used for in vitro and in vivo gene therapy researches, there have been few studies systematically examining various conditions that may affect the determination of the number of viable vector particles in a vector preparation and the use of Multiplicity of Infection (MOI) as a parameter for the prediction of gene transfer events. METHODS: Lentiviral vectors encoding a marker gene were packaged and supernatants concentrated. The number of viable vector particles was determined by in vitro transduction and fluorescent microscopy and FACs analyses. Various factors that may affect the transduction process, such as vector inoculum volume, target cell number and type, vector decay, variable vector - target cell contact and adsorption periods were studied. MOI between 0-32 was assessed on commonly used cell lines as well as a new cell line. RESULTS: We demonstrated that the resulting values of lentiviral vector titre varied with changes of conditions in the transduction process, including inoculum volume of the vector, the type and number of target cells, vector stability and the length of period of the vector adsorption to target cells. Vector inoculum and the number of target cells determine the frequencies of gene transfer event, although not proportionally. Vector exposure time to target cells also influenced transduction results. Varying these parameters resulted in a greater than 50-fold differences in the vector titre from the same vector stock. Commonly used cell lines in vector titration were less sensitive to lentiviral vector-mediated gene transfer than a new cell line, FRL 19. Within 0-32 of MOI used transducing four different cell lines, the higher the MOI applied, the higher the efficiency of gene transfer obtained. CONCLUSION: Several variables in the transduction process affected in in vitro vector titration and resulted in vastly different values from the same vector stock, thus complicating the use of MOI for predicting gene transfer events. Commonly used target cell lines underestimated vector titre. However, within a certain range of MOI, it is possible that, if strictly controlled conditions are observed in the vector titration process, including the use of a sensitive cell line, such as FRL 19 for vector titration, lentivector-mediated gene transfer events could be predicted.     

BOLD钉治疗桡骨小头骨折的临床疗效分析

目的:报告BOLD钉治疗Mason II型、未累及桡骨颈的Mason III型桡骨小头骨折的临床疗效。方法:自2009年3月至2012年2月对25例Mason II型,12例Mason III型桡骨小头骨折均采用切开复位BOLD钉内固定。结果:所有患者术后均获得随访12-24个月,平均随访14个月,肘关节功能评分:Mason II型平均分94分(88-98分),其中,优20例,良3例,可2例,差0例,优良率92%;Mason III型平均分91分(80-95分)其中,优9例,良1例,可2例,差0例,优良率83.3%。结论:BOLD钉治疗Mason II型及未累及桡骨颈的Mason III型桡骨小头有手术操作简单,固定稳定,允许早期活动等优点,可以作为这类骨折治疗的新选择。     

烟田中静电喷雾和电动喷雾下噻虫嗪的防效及对昆虫群落的影响

【目的】探明静电喷雾与电动喷雾对噻虫嗪防治害虫效果及烟田昆虫群落的影响,为静电喷雾在烟草上的推广应用提供理论依据。【方法】利用静电喷雾与电动喷雾法喷施0.66 g·L~(-1)25%噻虫嗪水分散粒剂,施药1、3、7 d后,测定2种方法对烟蚜与斜纹夜蛾的防治效果、在烟株与土壤中的沉积以及对昆虫群落的影响。【结果】喷施25%噻虫嗪水分散粒剂1、3、7 d后,静电喷雾对烟蚜和斜纹夜蛾的防治效果均显著高于电动喷雾的防治效果,且防治效果均随时间的推移而升高。噻虫嗪在静电喷雾处理区烟叶上的沉积量高于电动喷雾处理区烟叶上的沉积量,而在静电喷雾处理区土壤中的沉积量低于电动喷雾处理区土壤中的沉积量,且都随时间的推移而降低。静电喷雾与电动喷雾均引起烟田昆虫群落的变化,静电喷雾引起的害虫和中性昆虫的数量变化大于电动喷雾,但天敌昆虫的数量变化小于电动喷雾,且静电喷雾区烟田的物种丰富度明显高于电动喷雾区,可见静电喷雾施药对烟田昆虫群落的影响小于电动喷雾施药。静电喷雾的S_t/S_i与S_n/S_p比值明显高于电动喷雾,说明静电喷雾烟田中昆虫群落稳定性高于电动喷雾烟田中昆虫群落的稳定性。【结论】相比电动喷雾,静电喷雾能够提高噻虫嗪在烟叶上的沉积量,从而提高噻虫嗪对害虫的防治效果,同时减少噻虫嗪在土壤中的沉积量,提高噻虫嗪的生态安全性,因此,静电喷雾在烟草病虫害防治上具有较好的应用前景。     

Low testosterone levels are inversely correlated with carotid artery plaque formation in elderly women

Objective To study the relationship between serum testosterone levels and the plaque formation of the carotid artery in a population-based cohort of independently living healthy women above 60 years of age. Methods Analysis of the healthy elders from a population-based cohort study in 9 communities of Beijing. Carotid intima-media thickness and atherosclerotic plaques were determined ultrasonographically. Serum testosterone levels were measured by immunoassay. The data were analyzed with ANOVA and logistic regression analysis. Results There was an inverse correlation between testosterone and plaque formation in old females（P〈0.01）, while no association was found in males. Female with testosterone levels in the lowest quartile （〈0.49 nmol/L） had more risk of plaque formation（OR=3.805, P〈0.01） after adjusted with age and other traditional factors of atherosclerosis. Conclusion Testosterone concentrations are negatively associated with carotid artery atherosclerosis in old women in Beijing, experimental and prospective studies are needed to determine the possible therapeutic role of testosterone in atherosclerosis.     

亚硫酸钠和亚硫酸氢钠混合液对2种云杉某些生理指标影响的比较

八年生嫩江云杉和红皮云杉苗木,经喷施20、50、100mmol·L-1Na2SO3和NaHSO3(摩尔浓度为3:1)的混合液后第3、11、20天测定多个生理指标的结果显示,喷后第3天,2种云杉的净光合速率(Pn),光系统II(PSII)的最大光能转换效率(Fv/Fm),光化学量子效率(ΦPSII),叶绿素a(Chla)、叶绿素b(Chlb)和类胡萝卜素含量均下降;相对电导率上升;苗木受到胁迫的程度随着Na2SO3和NaHSO3混合液浓度的提高而增大。喷后第8~20天各种生理指标开始恢复。气孔导度(Gs)和胞间CO2浓度(Ci)变化不显著。红皮云杉对胁迫的敏感度高于嫩江云杉,但其在重度胁迫后的修复能力强于嫩江云杉。     

含笑小孢子的发生、雄配子体的发育及其系统学意义

含笑的花药具4个小孢子囊,花药壁由表皮、药室内壁、3～6层中层和绒毡层组成。绒毡层细胞在发育后期由单核分裂为2核,原位解体,为腺质型;小孢子母细胞在减数分裂过程中胞质分裂为同时型,小孢子四分体为四面体型,也有左右对称型的;成熟花粉为3细胞型。在前人对含笑小孢子发生和雄配子体发育的观察描述基础上,丰富了含笑的胚胎学资料,并对其系统学意义进行了探讨。