Widespread protein N-phosphorylation in organism revealed by SiO2@DpaZn beads based mild-acidic enrichment method.

Protein phosphorylation is one of the most commonly studied and ubiquitous post-translational modifications (PTMs), and defining site-specific phosphorylation is essential to understand basic and disease biology. However, the chemical properties and biological activities hamper the detection of non-canonical N-phosphorylation from biological samples, and the study of N-phosphorylation over the last half century has lagged behind canonical O-phosphorylation. Here, a mild-acidic method based-on SiO2@DpaZn beads was developed for protein N-phosphorylation sites identification. The method was verified as an effective complement for neutral enrichment science the stability of N-phosphorylation varied with the protein context. We firstly verified the feasibility of the mild-acidic enrichment strategy by standard peptides. Totally, 301 and 1476 N-phosphorylation sites were identified from E. coli and HeLa, respectively, verifying the robust of the method. The results greatly enriched N-phosphorylation site database. Furthermore, the method provided the peptide sequence motif of the N-phosphorylation sites and the biological functions of the identified proteins. The work represented an important step forward in studying the role of N-phosphorylation and other labile phosphorylation.

Periodontal treatment for cardiovascular risk factors: a systematic review / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy of periodontal treatment for the management of cardiovascular risk factors.</p><p><b>METHODS</b>Eligible studies in Cochrane Controlled Trials Register/CENTRAL, PubMed, EMBASE, and China Biology Medicine disc (CBMdisc) were searched until October 13, 2011. References of the included studies were hand searched. Two reviewers assessed the risk of bias and extracted the data of the included studies in duplicate. Meta-analysis was conducted with Revman 5.1.</p><p><b>RESULTS</b>Six randomized controlled trials involving 682 participants were included. One case had low risk of bias, another one had moderate risk of bias, and the remaining four had high risk of bias. Meta-analysis showed that periodontal treatment has no significant effect on C-reactive protein, total cholesterol, low-density lipoprotein cholesterol, and triglycerides (P > 0.05). However, the treatment had a significant effect on high-density lipoprotein cholesterol [MD = 0.05, 95% CI (0.00, 0.09), P = 0.04].</p><p><b>CONCLUSION</b>Periodontal treatment has good effects on controlling high-density lipoprotein cholesterol although more randomized controlled trials must be conducted to verify its effectiveness.</p>

New Development of Quantitative Mass Spectrometry-Based Proteomics / 分析化学

Mass spectrometry has become a powerful technique for proteomics analysis. It would be highly desirable to obtain exact quantitative values of each protein in a system, and these dynamic protein data obtained from cell can provide important information to study protein function, reveal the biological process and discover protein biomarker and drug target. Here, we report the development of quantitative mass spectrometry-based proteomics on strategy, method and application in recent years and further it is addressed for their characteristics and potentialities in protein analysis.

Clinical analysis of 18 cases with solitary bone plasmacytoma / 肿瘤研究与临床

Objective To improve the diagnosis level of solitary bone plasmacytoma (SBP) through analysing the clinical characteristics and therapy of this disease. Methods The clinical data of 18 cases were retrospectively analysis since 1999 in five hospitals, the clinical characteristics and therapeutic effect was summarized. Results The average age of 18 cases is 54.2 year (35-78), male were 1.6 times than female. 8 of 10 patients survived for 1-10 year after chemoradiotherapy, 2 of them progressed to multiple myeloma (MM)and died. 5 of 8 patients survived after only chemotherapy or radiotherapy. There were 11 cases of all patients in continue complete remission (CCS), the average CCS time was 47.3 months. Conclusion SBP is a type low-grade malignant tumor. Chemotherapy and radiotherapy is the main therapy. The patients can gain satisfactory prognosis with chemoradiotherapy, part of them can progress to MM.

On-column Enrichment with Field Amplified Sample Stacking in Capillary Zone Electrophoresis / 分析化学

FASS(field amplified sample stacking) is a technique for on-column enrichment in capillary zone electrophoresis. The distribution of solute in column during injection can be divided into two parts: the stack zone in running buffer and the sample solution zone imported by electroosmosis. Based on the investigation of transfer of solute in column, the results showed that the relationship between the length of two zone and injection time was nonlinear, so the relationship of injecting size that related with the mobility of solute and injection time. The increasing of the enrichment effect will not synchronize with the increasing of injection size, and the enrichment effect is decreased due to the laminar flow. To hold a basic constant column efficiency and desire enrichment effect, the ratio of mobility of solute in two zones should be maximum, and the injection time should also match with the ratio.

N-Terminal Cyclization of Peptides in LargE-scale Protein Identification Based on Biological Mass Spectrometry / 分析化学

Biological mass spectrometry has been developed for the largE-scale protein identification. The successful identification of protein in proteomic study is based on an effective match of MS data to the sequence in database. Because of the diversity and heterogeneity of protein modification, the experimental data obtained by mass spectrometry does not match the theoretical value sometimes, which makes about 90 percent or more of the tandem mass spectra not be effectively identified. This has become one of the most important technique issues to be resolved in current proteome research. The N-terminal cyclization of peptides, as one of a variety of modification introduced in sample preparation, has been preliminarily studied in this work. The result showed that N-terminal cyclization occurred at the most of the glutamine(Q) or carbamoylmethyl-cysteine(CAM_C) residues and the reaction is often incomplete or partial, both types of peptides could often exist in its respective state at the same time, and the behavior of modified peptides in revered phase chromatography is also changed. The success rate of protein identification could be obviously improved if adding the N-terminal cyclization modification in the database searching. These results will be very helpful in the mass spectrometric data analysis of proteomic study.

The application of spline wavelet transform to the determination of electroosmotic mobility in capillary electrophoresis.

The rule of current change was studied during capillary electrophoresis (CE) separation process while the conductivity of the sample solution was different from that of the buffer. Using a quadratic spline wavelet of compact support, the wavelet transforms (WTs) of capillary electrophoretic currents were performed. The time corresponding to the maximum of WT coefficients was chosen as the time of current inflection to calculate electroosmotic mobility. The proposed method was suitable for different CE modes, including capillary zone electrophoresis, nonaqueous CE and micellar electrokinetic chromatography. Compared with the neutral marker method, the relative errors of the developed method for the determination of electroosmotic mobility were all below 2.5%.