Algorithmic approach to diagnosis and management of post-refractive surgery dry eye disease

Dry eye disease (DED) is a condition that is fast reaching epidemic proportions around the world. Dry eye post-refractive surgery is the leading cause of iatrogenically induced DED. The wide variety of presentations and the disparity between signs and symptoms in many patients make this a very challenging aspect of our clinical practice. There has been a paradigm shift in the way we approach and treat this condition. The International Dry eye workshop has added new knowledge and focus to our management of dry eye. A wide range of newer diagnostic modalities are available for the diagnosis of DED. Dry eye is one of the most common side effects of refractive surgery and can have a bearing the patient''s perception of surgical outcomes as well. A thorough understanding of the possible underlying etiopathologies of this disease and the difference in etiopathogenesis of postrefractive dry eye is essential for optimal outcomes. It is important to approach each case in a unique fashion and customize the therapy to the patient presentation. This review article compiles all these aspects of management of dry eye in general, and postrefractive surgery dry eye in particular; from the ones commonly practiced in the clinic to the newer modalities of therapy with insights into the disease from a more practical point of view.     

独立成分分析及其应用的研究进展

独立成分分析(ICA)是一项把混合信号分解成具有统计独立性成分的新技术。ICA近年已在生物医学和雷达等领域的信号分离中展示了很好的应用前景。我们比较系统地介绍了ICA的基本原理、主要算法、应用和将来ICA研究的发展方向，旨在进一步推动有关的理论与应用研究工作。     

卵巢癌风险预测模型在上皮性卵巢癌早期诊断中的应用价值

目的：探讨卵巢癌风险预测模型（ROMA）对上皮性卵巢癌患病风险的评估价值及与患者临床病理分期的关联性,为上皮性卵巢癌的临床诊疗及预后分析提供依据。方法：回顾性分析经术后石蜡切片病理确诊的135例卵巢肿瘤患者的临床资料,将其分为卵巢良性肿瘤组（n=66）、上皮性卵巢癌组（n=58）和非上皮性卵巢癌组（n=11）。根据各组患者术前检测的血清人附睾蛋白4（HE4）和糖类抗原125（CA125）水平计算其ROMA值,根据各组患者HE4、CA125和ROMA临界值计算HE4、CA125和ROMA阳性率,分析卵巢癌患者血清HE4、CA125和ROMA阳性率与患者临床分期之间的关系,评价其对卵巢肿瘤患者的诊断效能。结果：上皮性卵巢癌组患者血清HE4、CA125水平和ROMA值均明显高于卵巢良性肿瘤组及非上皮性卵巢癌组（P<0.05）。上皮性卵巢癌组患者HE4、CA125和ROMA阳性率均高于卵巢良性肿瘤组（P<0.01）,并随着临床分期的升高而升高。与HE4和CA125阳性率比较,卵巢良性肿瘤患者ROMA阳性率最低,在各期上皮性卵巢癌中ROMA阳性率均高于CA125阳性率。ROMA在绝经后卵巢肿瘤患者组的敏感度及阴性预测值均高于绝经前卵巢肿瘤患者组（P<0.05）,而特异度及阳性预测值在绝经前及绝经后卵巢肿瘤患者组间比较差异无统计学意义（P>0.05）。3项指标中,ROMA的各项诊断效能指标最高,CA125的各项诊断效能指标最低。结论：ROMA对上皮性卵巢癌风险的诊断价值高于CA125或HE4,对绝经后患者具有更好的诊断价值,可提高卵巢癌的早期诊断效能。     

An algorithm for choosing among smoking cessation treatments

Currently, there are nine validated medications, four validated psychosocial strategies, and three validated ways to deliver psychosocial treatments for smoking cessation. This article presents an algorithm based on a literature review and the author's clinical experience. The algorithm integrates the recommendations of the major guidelines and meta-analyses and provides rationales for its treatment decisions. The algorithm suggests a brief assessment followed by use of one to two medications and counseling in most smokers. Because all treatments appear equally effective and have few adverse events, the algorithm suggests clinicians inform smokers of the pros and cons of the different treatments, and recommend use of one or more of each. If a smoker fails to quit, the algorithm suggests an assessment of why relapse occurred and then a more intense treatment, a new treatment, or both.     

pH adjustment of human blood plasma prior to bioanalytical sample preparation

pH adjustment in bioanalytical sample preparation concerning ionisable compounds is one of the most common sample treatments. This is often done by mixing an aliquot of the sample with a proper buffer adjusted to the proposed pH. The pH of the resulting mixture however, does not necessarily have to be the same as the pH of the used buffer due to the significant buffer capacity of the sample. Calculation methods from titration technology were adapted and applied to this problem. The acid-base characteristics of human blood plasma and serum samples were determined and used to calculate the pH of buffer-plasma mixtures. Based on these parameters and the characteristics of the used buffers, two alternative methods were described to prepare buffers that lead to the proposed pH when mixed in the right volume ratio with human plasma samples. The resulting pH of several mixtures of different buffers with human blood plasma were in good accordance with the calculated pH. The proposed calculation methods and recommended buffer preparation methods may lead to more robust bioanalytical methods.     

Mapping and definition of HLA class I and II serologic epitopes using an unbiased reverse engineering strategy

Current models describing HLA epitopes are both theoretical and empirical. Each has limitations yielding discordant results and increasingly complex modeling. The models make a priori assumptions that epitopes must be present only on the mature protein, solvent accessible, on the ‘top’ (peptide binding surface) of the molecule, restricted to the same class as the antibody, and in the same position on the target allele if reactive to more than one locus. Results obtained counter to these assumptions are routinely discounted. For the 17th International Histocompatibility and Immunogenetics Workshop, we developed a reverse engineering algorithm to define epitopes without these assumptions on a cohort of 332 primary transplant pairs. Complete NGS typing of the transcribed (including leader) genomic DNA for 11 HLA loci of donor and recipient and DSA assignment by single antigen beads was performed. Our results show that, when grouped by 16 class I and II allele specific DSA, uniform clusters and 172 specific amino acid target epitopes are recognized by recipients despite originating from disparate HLA pairs. Data also show that these targets can be in the leader, alpha 3, transmembrane and cytoplasmic domains, thus calling into question current assumptions regarding immunogenic epitopes. Comparisons of amino acid epitopes defined by the Terasaki and Duquesnoy groups (TerEp and EpRegistry) are given.     

Evaluation of supplemental testing with the Multispot HIV-1/HIV-2 Rapid Test and APTIMA HIV-1 RNA Qualitative Assay to resolve specimens with indeterminate or negative HIV-1 Western blots

BackgroundThe use of Western blot (WB) as a supplemental test after reactive sensitive initial assays can lead to inconclusive or misclassified HIV test results, delaying diagnosis.ObjectiveTo determine the proportion of specimens reactive by immunoassay (IA) but indeterminate or negative by WB that could be resolved by alternative supplemental tests recommended under a new HIV diagnostic testing algorithm.Study designRemnant HIV diagnostic specimens that were reactive on 3rd generation HIV-1/2 IA and either negative or indeterminate by HIV-1 WB from 11 health departments were tested with the Bio-Rad Multispot HIV-1/HIV-2 Rapid Test (Multispot) and the Gen-Probe APTIMA HIV-1 RNA Qualitative Assay (APTIMA).ResultsAccording to the new testing algorithm, 512 (89.8%) specimens were HIV-negative, 55 (9.6%) were HIV-1 positive (including 19 [3.3%] that were acute HIV-1 and 9 [1.6%] that were positive for HIV-1 by Multispot but APTIMA-negative), 2 (0.4%) were HIV-2 positive, and 1 (0.2%) was HIV-positive, type undifferentiated. 47 (21.4%) of the 220 WB-indeterminate and 8 (2.3%) of the 350 WB-negative specimens were HIV-1 positive.ConclusionApplying the new HIV diagnostic algorithm retrospectively to WB-negative and indeterminate specimens, the HIV infection status could be established for nearly all of the specimens. IA-reactive HIV-infected persons with WB-negative results had been previously misclassified as uninfected, and HIV diagnosis was delayed for those with WB-indeterminate specimens. These findings underscore the limitations of the WB to confirm HIV infection after reactive results from contemporary 3rd or 4th generation IAs that can detect HIV antibodies several weeks sooner than the WB.     

常用分类算法在脑梗死预测中的比较研究

目的：比较常用分类算法对脑梗死的分类预测能力。方法：将反映动脉弹性的6个脉搏波参数加年龄、性别一共8个指标作为每个样本的特征。把样本按3∶1随机分为训练集和测试集两部分。分别利用人工神经网络（ANN）、贝叶斯（Bayes）、决策树（Decision Tree,DT）、K邻近法（k-NN）、支持向量机（SVM）算法构造分类器,使用各分类器对训练集样本进行学习以建立分类预测模型,再用测试集测试各个模型的分类准确度。结果：SVM分类器和DT分类器效果较好,准确率超过80%。结论：以反映血管弹性的脉搏波参数结合性别、年龄作为特征并使用SVM或者DT算法来构建分类预测模型,有一定实用价值。