抗原表位的研究进展及其应用

表位是抗原诱导免疫反应的基本功能单位。在免疫学研究与医疗实践中, 表位的鉴定与选择是决定成败的关键。本文综述了当前抗原表位的研究进展及其在疾病诊断、 疫苗研究、 疾病治疗等领域的应用。     

Estimating the prevalence of drinking problems among physicians

Objective

Surveys assessing alcohol use among physicians have most commonly employed the Alcohol Use Disorders Identification Test (AUDIT) or the AUDIT-C, the most common short version of the AUDIT. As with other screeners, prevalence estimation is dependent on the accuracy of the test as well as choice of the cutoff value. The aim of the current study is to derive more precise prevalence estimates of alcohol problems in physicians by correcting for false-positive and false-negative results.

Method

In the context of a survey, the AUDIT was sent out via email or standard postal service to all 2484 physicians in Salzburg, Austria. A total of 456 physicians participated. A published correction formula was used to estimate the real prevalence of alcohol use problems.

Results

Applying a cutoff of 5 points for the AUDIT-C, 15.7% of female and 37.7% of male physicians screened positive. Use of a correction based on general population data and the sensitivity and specificity of the AUDIT-C resulted in much lower prevalence rates: 4.0% for female and 9.5% for male physicians. Using the full AUDIT, 19.6% of the female physicians and 48% of the male physicians were screened positive. Using the correction, the estimated prevalence rates for females and males were 6.3% and 15.5%, respectively.

Conclusions

Our findings demonstrate that uncorrected screening results may markedly overestimate the prevalence of physicians drinking problems.     

亳芍内生真菌的分离与鉴定

目的 对亳芍内生真菌进行分离鉴定,旨在丰富其内生真菌资源种类。方法 利用马铃薯葡萄糖琼脂培养基进行亳芍内生真菌的分离、尖端菌丝挑取法进行纯化,利用分子生物学方法对其进行鉴定。结果 从亳芍中分离出24株内生真菌,初步鉴定为9属13种,分别为Fusarium,Talaromyces,Dactylonectria,Myxocephala,Llyonectria,Penicillium,Alternaria,Rhexocercosporidium,Lopadostoma。主要为镰刀属（占33%）。结论 本研究首次从亳芍中分离出内生真菌,呈多样性分布,丰富了芍药内生真菌的种质资源。     

二维超高效液相色谱质谱联用技术测定注射用头孢地嗪钠的杂质谱

目的 建立二维超高效液相色谱质谱联用法研究注射用头孢地嗪钠的杂质谱。方法 一维色谱采用Waters HSS T3 C18(100mm×2.1mm, 1.8μm);以磷酸盐缓冲液(取磷酸二氢钾0.87g,无水磷酸氢二钠0.22g,加水溶解并稀释至1000mL)为流动相A,乙腈为流动项B,梯度洗脱;柱温：35℃;流速：0.4mL/min;检测波长：215nm;进样量：3μL;二维色谱采用Waters BEH C18(50mm×2.1mm, 1.7μm);以0.1%甲酸水溶液为流动相A,0.1%甲酸的乙腈为流动项B,切峰后开始B相3min由2%到95%;柱温：35℃;流速：0.4mL/min;质谱采用Xevo G2-XS QTof MS系统,离子源为ESI源,离子源温度：110℃,毛细管电压：3.0KV,雾化器温度：450℃,雾化器流速：800L/h,扫描范围：m/z 100~2000,测定头孢地嗪主要杂质的一级和二级质谱,进行结构解析。结果 采用UPLC梯度洗脱方法可检出多种头孢地嗪异构体、降解杂质和高分子杂质等,检出杂质的个数和总量均较现行法定标准多。结论 本品的杂质在原料合成、制剂分装及运输储藏过程中均可产生,因此,应对原料和制剂生产过程中的关键技术指标和环境条件加以控制。     

Rapid and specific identification of 5 human pathogenic Vibrio species by multiplex polymerase chain reaction targeted to dnaJ gene

A multiplex polymerase chain reaction (PCR) method, specifically designed for application in routine diagnostic laboratories, was developed for identifying 5 human pathogen Vibrio species: Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio mimicus, and Vibrio alginolyticus. This assay directed toward the dnaJ gene was tested on a total of 355 strains representing 13 Vibrio species and 17 non-Vibrio species. Specific PCR fragments were produced in isolates belonging to the 5 target species and were absent from all strains other than these 5 species and non-Vibrio strains, indicating a high specificity of this multiplex PCR. The multiplex PCR for the detection of Vibrio pathogens in clinical specimens was experimentally applied to spiked stool samples. Only 1 specific amplicon was observed, corresponding to the pathogen spiked into the stool sample. The detection limitation was 10(5) to 10(6) cells per milliliter stool. Our data showed that this method represented a robust tool for the specific and rapid detection of the 5 major pathogenic Vibrio species.     

Systematic screening and structural characterization of dipeptides using offline 2D LC-LTQ-Orbitrap MS: A case study of Cordyceps sinensis

Cordyceps sinensis (C. sinensis) is a widely used and highly valuable traditional Chinese medicine. Several dipeptides have been detected in C. sinensis, but current scientific knowledge of its chemical makeup remains limited. In this study, an improved approach that integrates offline two-dimensional liquid chromatography (2D LC) separation, precursor ion list, library screening, and diagnostic ion filtering was established to systematically screen and characterize dipeptides in C. sinensis. Offline 2D LC integrating hydrophilic interaction LC and reverse phase separations was established to eliminate interference and identify the target dipeptides. A library containing the potential 400 dipeptides was created, and a precursor ion list with all theoretical precursor ions was adopted to trigger the MS/MS scan with high sensitivity. To identify dipeptides, the type and connection sequence of amino acids were determined according to the product ions. Ile and Leu residues were differentiated for the first time according to the characteristic ion at m/z 69.07. Ultimately, 170 dipeptides were identified or tentatively characterized from C. sinensis, and most are reported for the first time in this species herein. In addition, the identified dipeptides were also applied for discrimination among the three Cordyceps species, and 11 markers were identified. The obtained results provide a deeper understanding of the chemical basis of C. sinensis.     

应用VITEK2 Comoact全自动微生物测定仪对药品中金黄色葡萄球菌的鉴定

目的：通过由实验室自行选择采用先进的方法和手段对药品中的控制菌进行检查,以提高药品控制菌检查技术水平。方法采用传统的判别方法和VITEK2 Comoact全自动微生物测定仪鉴定方法对金黄色葡萄球菌进行鉴定。结果10批样品采用新旧方法结果均符合规定,阳性对照检出阳性菌。新方法和旧方法相比,对检验结果无明显影响。结论应用VITEK2 Comoact全自动微生物测定仪对药品中金黄色葡萄球菌的鉴定比传统方法更加快捷和准确。     

浅谈外科急腹症诊断和鉴别诊断的基本思路

目的深入探究外科急腹症的最优诊断和鉴别诊断方式。方法对2011年2月～2013年2月之间参与的132例外科急腹症患者的诊断和鉴别进行回顾性分析。结果132例外科急腹症通过诊断鉴别后,采取保守治疗84例,手术治疗48例,其中2例患者经保守治疗无效后进行手术治疗,最终痊愈131例,死亡1例。结论实施各种有效的辅助检查手段,对急腹症的临床特点进行分析总结,再加上采用合适的检测方式对于急腹症患者的正确诊断和有效治疗具有重大的临床意义。     

应用16SrRNA基因序列分析快速鉴定临床标本中的革兰氏阳性杆菌

目的探索一种快速鉴定临床标本中革兰氏阳性杆菌的方法。方法利用PCR技术扩增待检菌株的16SrRNA基因序列,通过分析待检菌株的16SrRNA基因序列对其进行鉴定。结果5株待检菌株的16SrRNA基因序列均成功扩增,其中4株的16SrRNA基因序列与基因库中已注册的核酸序列相似率达99．9％以上,将其鉴定到种的水平,1株的16SrRNA基因序列与基因库中雷弗森菌属的核酸序列相似率为97．09％,将其鉴定为雷弗森菌属。结论应用16SrRNA基因序列分析可快速、准确地鉴定临床标本中的革兰氏阳性杆菌。     

用单克隆抗体对牛型结核杆菌早期培养物进行菌型鉴定的研究

用抗牛型结核杆菌单克隆抗体（ＭｃＡｂ）１Ａ３和抗牛型结核杆菌免疫血清经酶联免疫吸附试验（ＥＬＩＳＡ）对１９种分支杆菌参考株进行检测，证明了抗牛型结核杆菌ＭｃＡｂ１Ａ３的特异性和抗牛型结核杆菌免疫血清（ＩＭＳ）的相对非特异性。用ＭｃＡｂ１Ａ３对３６株分支杆菌临床分离株的早期培养物（培养３周）进行菌型鉴定，所需菌量最少仅２×１０７，即可鉴定出临床分离株中的牛型结核杆菌，敏感性和特异性均为１００％。此方法较常规微生物鉴定方法简单、省时，是一种有发展前途的菌型鉴定方法。