Improving image analysis in 2DGE-based redox proteomics by labeling protein carbonyl with fluorescent hydroxylamine

Recent advances in redox proteomics have provided significant insight into the role of oxidative modifications in cellular signalling and metabolism. At present, these techniques rely heavily on Western blots to visualize the oxidative modification and corresponding two dimensional (2D) gels for detection of total protein levels, resulting in the duplication of efforts. A major limitation associated with this methodology includes problematic matching up of gels and blots due to the differences in processing and/or image acquisition. In this study, we present a new method which allows detection of protein oxidation and total protein on the same gel to improve matching in image analysis. Furthermore, the digested protein spots are compatible with standard MALDI mass spectrometry protein identification. The methodology highlighted here may be useful in facilitating the development of biomarkers, assessing potential therapeutic targets and elucidating new mechanisms of redox signalling in redox-related conditions

Proteomic Analysis of Protein Expression and Oxidative Modification in R6/2 Transgenic Mice A Model of Huntington Disease

Huntington disease (HD) is a hereditary neurodegenerative disorder characterized by motor, psychiatric, and cognitive symptoms. The genetic defect responsible for the onset of the disease, expansion of CAG repeats in exon 1 of the gene that codes for huntingtin on chromosome 4, has been unambiguously identified. On the other hand, the mechanisms by which the mutation causes the disease are not completely understood yet. However, defects in energy metabolism of affected cells may cause oxidative damage, which has been proposed as one of the underlying molecular mechanisms that participate in the etiology of the disease. In our effort to investigate the extent of oxidative damage occurring at the protein level, we used a parallel proteomic approach to identify proteins potentially involved in processes upstream or downstream of the disease-causing huntingtin in a well established HD mouse model (R6/2 transgenic mice). We have demonstrated that the expression levels of dihydrolipoamide S-succinyltransferase and aspartate aminotransferase increase consistently over the course of disease (10-week-old mice). In contrast, pyruvate dehydrogenase expression levels were found to be decreased in 10-week-old HD transgenic mice compared with young (4-week-old) mice. Our experimental approach also led to the identification of oxidatively modified proteins. Six proteins were found to be significantly oxidized in old R6/2 transgenic mice compared with either young transgenic mice or non-transgenic mice. These proteins are alpha-enolase, gamma-enolase (neuron-specific enolase), aconitase, the voltage-dependent anion channel 1, heat shock protein 90, and creatine kinase. Because oxidative damage has proved to play an important role in the pathogenesis and the progression of Huntington disease, our results for the first time identify specific oxidatively modified proteins that potentially contribute to the pathogenesis of Huntington disease

Study on Biodegradation of Polyunclear Aromatic Hydrocarbons with Molecular Luminescence Spectroscopy

建立了用荧光法研究有序介质影响生物降解水中多环芳烃(PAHs) 的方法. 实验结果表明, 有序介质的增溶作用可加速PAHs 的降解. 该方法的优点是快速、简单.福建省自然科学基金资助项目(D9910008

A 2-year prospective evaluation of the Prostate Health Index in guiding biopsy decisions in a large cohort

Objectives: To prospectively evaluate how the Prostate Health Index (PHI) impacts on clinical decision in a real-life setting for men with a prostate-specific antigen (PSA) level between 4 and 10 ng/mL and normal digital rectal examination. Patients and Methods: Since 2016, the PHI has been available at no cost to eligible men in all Hong Kong public hospitals. All eligible patients who received PHI testing in all public Urology units (n = 16) in Hong Kong between May 2016 and August 2017 were prospectively included and followed up. All included men had a PHI test, with its result and implications explained; the subsequent follow-up plan was then decided via shared decision-making with urologists. Patients were followed up for 2 years, with outcomes including prostate biopsy rates and biopsy findings analysed in relation to the initial PHI measurements. Results: A total of 2828 patients were followed up for 2 years. The majority (82%) had PHI results in the lower risk range (score &lt;35). Knowing the PHI findings, 83% of the patients with elevated PSA decided not to undergo biopsy. In all, 11% and 45% opted for biopsy in the PHI score &lt;35 and ≥35 groups, respectively. The initial detection rate of International Society of Urological Pathology (ISUP) Grade Group (GG) ≥2 cancer was higher in the PHI score ≥35 group (23%) than in the PHI score &lt;35 group (7.9%). Amongst patients with no initial positive biopsy findings, the subsequent positive biopsy rate for ISUP GG ≥2 cancer was higher in the PHI score ≥35 group (34%) than the PHI score &lt;35 group (13%) with a median follow-up of 2.4 years. Conclusion: In a real-life setting, with the PHI incorporated into the routine clinical pathway, 83% of the patients with elevated PSA level decided not to undergo prostate biopsy. The PHI pathway also improved the high-grade prostate cancer detection rate when compared to PSA-driven strategies. Higher baseline PHI predicted subsequent biopsy outcome at 2 years. The PHI can serve as a tool to individualise biopsy decisions and frequency of follow-up visits.</p

MiR-122 targets pyruvate kinase M2 and affects metabolism of hepatocellular carcinoma

10.1371/journal.pone.0086872PLoS ONE91-POLN

Wild Type and Mutant 2009 Pandemic Influenza A (H1N1) Viruses Cause More Severe Disease and Higher Mortality in Pregnant BALB/c Mice

BACKGROUND: Pregnant women infected by the pandemic influenza A (H1N1) 2009 virus had more severe disease and higher mortality but its pathogenesis is still unclear. PRINCIPAL FINDINGS: We showed that higher mortality, more severe pneumonitis, higher pulmonary viral load, lower peripheral blood T lymphocytes and antibody responses, higher levels of proinflammatory cytokines and chemokines, and worse fetal development occurred in pregnant mice than non-pregnant controls infected by either wild type (clinical isolate) or mouse-adapted mutant virus with D222G substitution in hemagglutinin. These disease-associated changes and the lower respiratory tract involvement were worse in pregnant mice challenged by mutant virus. Though human placental origin JEG-3 cell line could be infected and proinflammatory cytokines or chemokines were elevated in amniotic fluid of some mice, no placental or fetal involvement by virus were detected by culture, real-time reverse transcription polymerase chain reaction or histopathological changes. Dual immunofluorescent staining of viral nucleoprotein and type II alveolar cell marker SP-C protein suggested that the majority of infected alveolar epithelial cells were type II pneumocytes. CONCLUSION: The adverse effect of this pandemic virus on maternal and fetal outcome is largely related to the severe pulmonary disease and the indirect effect of inflammatory cytokine spillover into the systemic circulation

Study on the Interaction of Pyrene and Humic Acid by Fluorometry

[中文文摘]建立了用荧光猝灭法研究芘与腐植酸间的相互作用的方法． 本方法的优点是不经分离即可测定荧光物的结合常数．[英文文摘]A fluorescence quenching method has been developed for determination association constant of pyrene with dissolved humic acids.The technique is based upon the observation that pyrene fluorescence in aqueous solution is quenched upon association with humic acid.The great advantage of this method is that the association constant of some kinds of fluorephors in a sample can be measured without separation