title: Peak tree: a new tool for multiscale hierarchical representation and peak detection of mass spectrometry data.
abstract: Peak detection is one of the most important steps in mass spectrometry (MS) analysis. However, the detection result is greatly affected by severe spectrum variations. Unfortunately, most current peak detection methods are neither flexible enough to revise false detection results nor robust enough to resist spectrum variations. To improve flexibility, we introduce peak tree to represent the peak information in MS spectra. Each tree node is a peak judgment on a range of scales, and each tree decomposition, as a set of nodes, is a candidate peak detection result. To improve robustness, we combine peak detection and common peak alignment into a closed-loop framework, which finds the optimal decomposition via both peak intensity and common peak information. The common peak information is derived and loopily refined from the density clustering of the latest peak detection result. Finally, we present an improved ant colony optimization biomarker selection method to build a whole MS analysis system. Experiment shows that our peak detection method can better resist spectrum variations and provide higher sensitivity and lower false detection rates than conventional methods. The benefits from our peak-tree-based system for MS disease analysis are also proved on real SELDI data.
authors.affiliation: Department of Electronics Engineering and Information Science, University of Science and Technology of China, PO Box 4, Hefei, Anhui 230027, P.R. China. charmp@mail.ustc.edu.cn
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.forename: Houqiang
authors.initials: H
authors.lastname: Li
authors.forename: Honghui
authors.initials: H
authors.lastname: Wang
authors.forename: Stephen T C
authors.initials: ST
authors.lastname: Wong
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000465:Algorithms; D015415:Biomarkers / Q000737:chemistry; D019295:Computational Biology / Q000379:methods*; D030562:Databases, Protein; D013058:Mass Spectrometry / Q000379:methods*; D016011:Normal Distribution; D011506:Proteins / Q000737:chemistry*; D012372:ROC Curve; D058067:Wavelet Analysis
chemical_list: D015415:Biomarkers; D011506:Proteins