核酸适配体在感染性疾病诊治中的研究进展

临床上，感染性疾病由于诊断不明或诊断时间较长导致严重后果的情况并不罕见。近年来，由于新型病原体感染报道层出不穷，现有病原体出现耐药也十分普遍，导致感染性疾病的诊断和治疗仍是临床上亟待解决的难题。核酸适配体是通过体外反复筛选或指数富集配体系统进化(systematic evolution of ligands by exponential enrichment，SELEX)技术筛选出来的一类具有特异性识别能力的寡核苷酸序列，具有靶向结合目标分子的能力，可用于病原体检测和新型治疗性药物的开发。适配体已在感染性疾病诊治中显现良好的应用前景，进一步推进相关研究有望为感染性疾病的诊治提供新的途径。     

江西官山自然保护区瘿椒树群落特征及保护策略

对江西官山自然保护区的典型瘿椒树(Tapiscia sinensis)群落进行调查。结果表明：(1)群落共有维管植物54科78属104种；(2)群落中植物区系组成以北温带分布为主，泛热带分布次之，属于典型的中亚热带山地群落；(3)对立木层进行重要值分析显示，钩锥(Castanopsis tibetana)、瘿椒树、紫楠(Phoebe sheareri)和拟赤杨(Alniphyllum fortunei)是群落优势种；(4)径级与高度级分析显示，瘿椒树种群处于衰退阶段，但占据了顶层空间，具有竞争优势，整体状态稳定；(5) Raunkiaer频度关系为A＞B＞D＞C＞E，符合亚热带山地常绿阔叶林的分布规律；(6) α多样性分析显示，群落Simpson多样性指数0.88，Shannon-Wiener多样性指数3.65，Pielou均匀度0.73。本文调查的官山瘿椒树群落是官山地区少数的几个瘿椒树群落之一，群落多样性较高，具有重要的科研价值和实用价值，但瘿椒树种群整体处于衰退型，未来宜采用就地或迁地方式开展保护。     

Selection and Identification of Aptamers Against B Cell Activating Factor

Systemic lupus erythematosus (SLE) is the most common autoimmune disease in China. B cell activating factor (BAFF) is an important target for the treatment and detection of SLE. It is of great significance to develop novel molecular recognition elements with high affinity for BAFF. In this study, artificial nucleic acid aptamers against BAFF were screened from a 78 nt single-stranded DNA random library by systematic evolution of ligands exponential enrichment (SELEX) in vitro based on several selection and amplification steps. Through ten rounds of selection, the aptamers with high specificity and affinity for BAFF were identified. After high-throughput sequencing, several aptamers were selected and further examined for binding affinity and specificity. The investigation by dot blotting, Eastern blotting analyses and enzyme-linked oligonucleotide assay (ELONA) showed that the aptamers Apt 7 and Apt 12 with dissociation constants of 241.00±19.75 nmol/L and 413.51±46.94 nmol/L were able to recognize BAFF specifically. After molecular docking analysis, Apt 7 was truncated to Apt 7～1, and the dissociation constant was 192.10±28.61 nmol/L. A sandwich ELONA using Apt 7～1 and BAFF antibodies was established to detect BAFF. The detection limit was estimated to be 0.227 nmol/L. This study provides new molecular recognition elements for the detection of BAFF and the study of antagonists.     

基于低相干光干涉的眼睛光学生物参数测量研究

目的 眼睛的光学生物参数中的眼轴长度（AL）和角膜曲率半径（CR）可以作为预防和监测眼球近视的两个重要参数。为了提高测量眼轴长度的速度与精度和同步实现角膜曲率高精度动态测量，本文提出一种基于低相干光干涉技术眼睛光学生物参数测量的系统。方法 该系统使用旋转光学延迟线快速改变参考光的光程，利用曲率半径为8 mm的标准件标定人眼角膜顶点到靶环之间的距离，利用角膜的干涉信号对相机和数据采集卡进行触发实现同步采集，从而实现眼轴长度的快速测量和精准定位靶环到角膜顶点之间的距离，同时保证成像系统的放大倍率恒定和数据的实时采集。结果 实验结果表明，这种低相干光干涉测量系统，可以实时测量眼轴长度和角膜曲率半径，眼轴长度误差低于40 μm，人眼角膜曲率半径方差为2.082 36×10^-2 μm。结论 该系统能够快速、精准地测量AL和CR，可在近视的预防和监测中发挥重要作用。