MS-based proteomics has emerged as a powerful tool in biological studies. The shotgun proteomics strategy, in which proteolytic peptides are analyzed in data-dependent mode, enables a detection of the most comprehensive proteome (>10 000 proteins from whole-cell lysate). The quantitative proteomics uses stable isotopes or label-free method to measure relative protein abundance. The isotope labeling strategies are more precise and accurate compared to label-free methods, but labeling procedures are complicated and expensive, and the sample number and types are also limited. Sequential window acquisition of all theoretical mass spectra (SWATH) is a recently developed technique, in which data-independent acquisition is coupled with peptide spectral library match. In principle SWATH method is able to do label-free quantification in an MRM-like manner, which has higher quantification accuracy and precision. Previous data have demonstrated that SWATH can be used to quantify less complex systems, such as spiked-in peptide mixture or protein complex. Our study first time assessed the quantification performance of SWATH method on proteome scale using a complex mouse-cell lysate sample. In total 3600 proteins got identified and quantified without sample prefractionation. The SWATH method shows outstanding quantification precision, whereas the quantification accuracy becomes less perfect when protein abundances differ greatly. However, this inaccuracy does not prevent discovering biological correlates, because the measured signal intensities had linear relationship to the sample loading amounts; thus the SWATH method can predict precisely the significance of a protein. Our results prove that SWATH can provide precise label-free quantification on proteome scale.

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The Riccati-Bernoulli sub-ODE method is firstly proposed to construct exact traveling wave solutions, solitary wave solutions, and peaked wave solutions for nonlinear partial differential equations. A Bäcklund transformation of the Riccati-Bernoulli equation is given. By using a traveling wave transformation and the Riccati-Bernoulli equation, nonlinear partial differential equations can be converted into a set of algebraic equations. Exact solutions of nonlinear partial differential equations can be obtained by solving a set of algebraic equations. By applying the Riccati-Bernoulli sub-ODE method to the Eckhaus equation, the nonlinear fractional Klein-Gordon equation, the generalized Ostrovsky equation, and the generalized Zakharov-Kuznetsov-Burgers equation, traveling solutions, solitary wave solutions, and peaked wave solutions are obtained directly. Applying a Bäcklund transformation of the Riccati-Bernoulli equation, an infinite sequence of solutions of the above equations is obtained. The proposed method provides a powerful and simple mathematical tool for solving some nonlinear partial differential equations in mathematical physics. MSC: 35Q55; 35Q80; 35G25

Objective• To compare extended pelvic lymph node dissection (ePLND) with non-extended pelvic lymph node dissection (non-ePLND) and assess their influence on recurrence-free survival (RFS) in patients undergoing radical cystectomy for bladder cancer. Methods• Through a comprehensive search of the PubMed, Embase and Cochrane Library databases in September 2012, we performed a systematic review and cumulative meta-analysis of all comparative studies assessing the extent of pelvic lymph node dissection (PLND) and its influence on RFS. Results• Six studies with a total of 2824 patients were identified.• Overall analysis showed a significantly better RFS rate in patients who had undergone ePLND than in those who had undergone non-ePLND (hazard ratio [HR]: 0.65; P < 0.001).• A subgroup analysis found that, compared with non-ePLND, ePLND was associated with a better RFS rate for both patients with negative lymph nodes (HR: 0.68; P = 0.007) and those with positive lymph nodes (HR: 0.58; P < 0.001). When stratified by pathological T stage, ePLND provided additional RFS benefits for patients with pT3-4 disease (HR: 0.61; P < 0.001), but not for patients with ≤pT2 disease (HR: 0.95; P = 0.81). Conclusions• The results of this meta-analysis indicate that ePLND provides a RFS benefit compared with non-ePLND. On subgroup analysis, ePLND provides better RFS not only for patients who had positive lymph nodes and pT3-4 disease, but also for patients with negative lymph nodes.• Two randomized controlled trials on ePLND vs non-ePLND are awaited which should provide more clinically meaningful results.