应用噬菌体控制假单胞菌的研究进展

假单胞菌属细菌中的部分菌株是动植物和人类的致病菌，也是食品的腐败菌，会导致动植物和人类的高死亡率和严重的食品安全事故。噬菌体作为一种细菌性病毒，特异性高、自我增殖快且无副作用。这些特性使其成为了解决细菌性问题的新思路和新方法。本文就利用噬菌体防控假单胞菌属致病菌和腐败菌在食品、水产、植物、医疗等方面的研究和应用进行综述，以便为后期的深入研究提供一定的参考。     

Children's categorisation of play and learning based on social context

While much time has been spent deliberating about the definition of play, little emphasis has been placed on what children themselves perceive as play. The aim of the present study was to examine social context as a cue for children's perceptions of play and learning. Ninety-two children aged between four and six years (mean four years nine months) participated in the study and completed the Activity Apperception Story Procedure. Children were asked to sort photographic stimuli into those they believed depicted play/not play and learning/not learning. Each of the stimuli were identified by independent raters as containing one of the following social cues; teacher absence (solitary activity, parallel activity or cooperative activity) or teacher presence (teacher involved activity or teacher directed activity). Findings revealed that children associated teacher absence with play. More specifically, children made links between play and the presence of peers (parallel and cooperative activity). Findings are discussed in relation to play in the early years curriculum, differences in children's early educational experiences and the importance of understanding children's perceptions of play.     

A cyclic peptide–polymer probe for the detection of Clostridium botulinum neurotoxin serotype A

A Botulinum neurotoxin serotype A (BoNT/A) ELISA detection system was developed based upon an 11-mer cyclic peptide, termed C11-019, that was identified through peptide phage display technology. The assay employs a sandwich format using the C11-019 cyclic peptide attached to a PEMA (poly(ethylene maleic anhydride)) matrix as the capture phase and anti-BoNT/A polyclonal antibodies as the detection phase. Results reported demonstrate that the C11-019 peptide–polymer can specifically bind to BoNT/A with no cross-reactivity to other serotypes examined in assay buffers and a variety of body fluids and foodstuffs. When a highly sensitive chemiluminescent substrate was engaged, the detection of 1 pg/mL could be readily achieved within 3 h with a linear range of 0.1–1 ng/mL. These results demonstrate that an inexpensive peptide–polymer-based capture ELISA system can be used for rapid, sensitive and highly specific BoNT detection.     

抗地高辛人源小分子抗体的获取

目的 从大容量噬菌体抗体库中筛选人源性抗地高辛抗体,并构建双体抗体.方法 以固相化的地高辛对构建的大容量噬菌体抗体库进行筛选,3～4轮后挑取克隆用酶联免疫吸附测定方法鉴定其特异性,对抗地高辛阳性抗体克隆进行DNA指纹分析及测序分析.选取活性好的克隆进行改造,构建双体抗体.结果 在抗体库的筛选过程中可见到明显的富集现象,获得了4株可与地高辛特异性结合的人源抗体,经DNA指纹分析及测序分析证明为不同克隆基因,阳性克隆的可变区基因轻链均属于λ第一亚群,重链分别属于第三和第四亚群.选取4号克隆进行基因改造,构建双体抗体表达载体,获得了活性较好的双体抗体.结论 利用噬菌体抗体技术获得了人源性抗地高辛抗体,并改造成应用前景较好的双体抗体,可能为临床诊断及治疗洋地黄类药物中毒提供具有实用价值的人源抗体.     

诱生型一氧化氮合酶特异性抑制肽的制备

目的：通过噬菌体展示技术筛选iNOS特异性抑制肽。方法：将iNOSFAD结合区及其附近序列的基因片段装入pET-28A( )，在大肠杆菌BL21中表达，His.bind^TM亲和层析柱纯化目的蛋白，使用纯化蛋白筛选Ph.D.-12^TM噬菌体库，筛选iNOS活性抑制作用较高的噬菌体克隆，测序并合成其中具有一致序列的短肽。结果：得到具有较高表达量的目的蛋白，经His.Bind^TM柱亲和层析纯化后纯度大于95％，以纯化蛋白筛选Ph.D.-12^TM噬菌体库，经4轮筛选获得10株iNOS活性抑制作用较高的噬菌体克隆，测序发现其中5株序列完全相同，合成该12肽，初步研究表明其对iNOS表现为高浓度抑制，低浓度兴奋的作用，而对nNOS及eNOS则没有影响。结论：以iNOSFAD片段蛋白为靶蛋白筛选得到的克隆对iNOS活性具有特异性影响，可根据这些特征设计合成小分子前导药物，创造新的活性药物。     

北京地区伤寒沙门菌Vi-Ⅱ噬菌体型及其药物敏感性监测

于１９７３～１９８９年收集北京地区伤寒沙门菌９６１株，做Ｖｉ－Ⅱ噬菌体分型及药物敏感性监测。结果分出３８个噬菌体型，主要噬菌体型为Ａ，Ｄ２，Ｅ１，Ｋ１，Ｄ５，Ｄ１，Ｏ，Ｄ４及Ｌ１型。药敏试验表明，１６８株北京地区菌与９６型Ｖｉ－Ⅱ标准菌相似，它们均对氯霉素高度敏感。     

Special issue: Group treatment after child and adolescent sexual abuse: Introduction

This introduction traces the increasing awareness of the prevalence of child sexual abuse over the last 20 years, examines the nature and consequences of such abuse and summarizes current information on the use of group treatment and its evaluation with sexually abused children and adolescents and their parents. Four examples of group treatment with different populations of abused children are described in this issue.     

Hurricane Hugo blows down the broccoli: Preschoolers' post-disaster play and adjustment

This article reports highlights from over 200 parents' observations of their preschoolers' play and verbalizations in the year following Hurricane Hugo. Commonly reported activities included reenactment and discussion of the event in multiple mediums, personification of Hugo, and expression of fears related to storms. Precocious concern for others, insight, and vocabulary were also noted. In these intact, relatively high functioning families, parents seemed able to facilitate their youngsters' adjustment without outside intervention.Portions of this report were presented in earlier form at the 1991 Society for Research in Child Development meeting in Seattle, Washington.     

Probing the ability of the coat and vertex protein of the membrane-containing bacteriophage PRD1 to display a meningococcal epitope

Bacteriophage PRD1 is an icosahedral dsDNA virus with a diameter of 740 A and an outer protein shell composed of 720 copies of major coat protein P3. Spike complexes at the vertices are composed of a pentameric base (protein P31) and a spike structure (proteins P5 and P2) where the N-terminal region of the trimeric P5 is associated with the base and the C-terminal region of P5 is associated with receptor-binding protein P2. The functionality of proteins P3 and P5 was investigated using insertions and deletions. It was observed that P3 did not tolerate changes whereas P5 tolerated changes much more freely. These properties support the hypothesis that viruses have core structures and functions, which remain stable over time, as well as other elements, responsible for host interactions, which are evolutionally more fluid. The insertional probe used was the apex of exposed loop 4 of group B meningococcal outer membrane protein PorA, a medically important subunit vaccine candidate. It was demonstrated that the epitope could be displayed on the virus surface as part of spike protein P5.