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Reactive oxygen species (ROS) is favorable for antibacterial infection but its overproduction results in serious inflammatory response and aggravates hypoxic state of wound tissue, which would be detrimental to healing stages of proliferation and remodeling. Here, an atomic-dispersion iron (Fe)-doped oxygen-deficient molybdenum oxide MoO

SynopsisObjective The objective of this work was to identify whether low levels of redox metals such as copper will accelerate damage to hair on exposure to UV irradiation and whether this damage can be prevented. Methods The methods used were proteomics to measure the protein damage via protein loss after different periods of exposure and mass spectroscopy methods to identify specific marker peptides that are specifically created by this type of damage. Results In this work, we have developed new insights into the mechanism of UV damage using these proteomic methods. A marker fragment in the hair protein loss extract was identified (m/z = 1279) that is unique to UV exposure and increases with time of UV exposure. We have also identified for the first time in hair the role of exogenous copper in increasing UV damage both in terms of total protein degradation and also increased formation of the marker fragment and proposed a mechanism of action. It has been demonstrated that shampoo treatment containing a chelant such as N,N'-ethylenediamine disuccinic acid (EDDS) reduced copper accumulation in hair. Conclusion This work provides evidence for the role of copper in UV-induced damage to hair and strategies to reduce copper levels in hair using a chelant such as EDDS.

Background Myocardial infarction (MI) remains the most common cause of heart failure (HF) worldwide. For almost 50 years, HF has been recognized as a determinant of adverse prognosis after MI, but efforts to promote myocardial repair have failed to be translated into clinical therapies. Aims In this study, we investigated the effects of BRD4 on cardiac function and the underlying mechanism. Material and methods The in vivo rat model of AMI and in vitro neonatal cardiomyocytes were established and cultured respectively, the BRD4 and NPPA/NPPB expression levels were detected by qPCR and Western blot, and interaction of BRD4 with acetylation RelA or NPPA/B promoters were examined by co-immunoprecipitation and chromatin immunoprecipitation assays, respectively. Results We found that BRD4 protein expression was significantly increased in cardiomyocytes of MI rat model and cardiomyocytes under hypoxia, accompanied by the expression of natriuretic peptide A (NPPA) and natriuretic peptide B (NPPB). Functionally, knockdown of BRD4 greatly downregulated the NPPA and NPPB in vivo and in vitro, improved the hemodynamic and biometric parameters in rat with heart failure, as well as decreased the apoptosis occurrence. In vitro studies further demonstrated that BRD4 bound with acetylated RelA to enhance the activation of NF-κb signaling, which resulted in activation of NPPA and NPPB transcriptions. Conclusions Taken together, our findings suggest that inhibition of BRD4 attenuated cardiomyocyte apoptosis via NF-κB pathway in myocardial infarction, and this study sheds light on developing new strategies to overcome myocardial damage.

Introduction Social isolation enhances the aggressive behavior of animals, but the detailed mechanism remains unclear. Epigenetic studies have suggested that Htr2c RNA editing is closely related to aggressive behavior. This study aims to obtain a fundamental understanding of how social isolation impacts adenosine deaminase acting on RNA 1 (ADAR1, RNA editing enzyme) and Htr2c RNA editing, leading to aggressive behavior, and explore the effective solutions for the recovery of this behavior. Methods We evaluated 21-day-old BALB/c mice with and without isolation for aggressive behavior using a resident-intruder test. Immune-reactivity and protein expression of ADAR1 (p110) were measured using immunohistochemistry and Western blotting. Htr2c RNA editing was evaluated using pyrosequencing. In addition, the 5-HT 2C R antagonist SB243213/5-HT 2C R inverse agonist SB206553 was used to treat the isolated mice, and the performance of both treatments on the behavior, ADAR1 (p110) expression, and Htr2c RNA editing in isolated mice was examined. Results Both the protein expression and immune-reactivity of ADAR1 (p110) in the amygdala decreased, but the percentage of Htr2c RNA editing at A and B sites of amygdala only showed a moderate increase in isolated BALB/c mice with enhanced aggressive behavior compared to the age-matched group-housed BALB/c mice. Additionally, treatment with the 5-HT 2C R antagonist SB243213/5-HT 2C R inverse agonist SB206553 recovered the enhanced aggressive behavior of isolated mice and returned the protein expression and immune-reactivity of ADAR1 (p110) back to the normal level. Moreover, compared to the age-matched isolated mice treated with physiological saline, isolated mice treated with 5-HT 2C R inverse agonist SB206553 showed a lower percentage of Htr2c RNA editing at both A and B sites, and the same result occurred in isolated mice treated with 5-HT 2C R antagonist SB243213 at B site of Htr2c RNA editing. Conclusions The 5-HT 2C R antagonist SB243213/5-HT 2C R inverse agonist SB206553 recovered increased aggressive behavior of isolated BALB/c mice mediated by ADAR1 (p110) expression and Htr2c RNA editing.

Monolayers of sulfanilamide on metallic surface can serve as an ideal model for understanding the interaction mechanism between the metal and the sulfanilamide molecule. In the present paper, the surface-enhanced Raman scattering (SERS) technique was employed to obtain the SERS spectra of sulfanilamide monolayers formed on the silver surface under different pH values. Assignments of the spectra were carried out with the aid of density functional theory (DFT) calculations (BLYP/6-311G). It can be found that the adsorption function of sulfanilamide on the silver surface was influenced by the pH value. The fully protonated sulfanilamide molecule adsorbed on the silver surface through N13H2 group and the benzene ring anchored in a relatively perpendicular manner leading to N7H2 and S10O2 groups near the surface, while the completely deprotonated sulfanilamide molecule attached on the silver surface via N7H2 and the benzene ring was perpendicular to, and the N13H2 and S10O2 groups were far from the silver surface. Copyright © 2009 John Wiley & Sons, Ltd.

Electrochemically anticorrosive behavior of 4-methyl-4H-1,2, 4-triazole-3-thiol (MTTL) self-assembled monolayers (SAMs) on the silver electrode was studied by means of electrochemical impedance spectroscopy (EIS) and polarization measurements. The promising inhibition effect of the MTTL for silver had been affirmed. Results of surface-enhanced Raman scattering (SERS) experiments indicated that the MTTL molecule in a tilted orientation was self-assembled on the silver surface through S' and N(2) atoms to form monolayers. An in situ electrochemical SERS experiment implied the changes of adsorption fashion of MTTL momolayers on the silver surface with the potential shifted to more negative direction. Copyright (C) 2009 John Wiley & Sons, Ltd.

A proteomic analysis was performed comparing normal rat soleus muscle to soleus muscle that had undergone either 0.5, 1, 2, 4, 7, 10 and 14 days of hindlimb suspension-induced atrophy or hindlimb suspension-induced atrophied soleus muscle that had undergone 1 hour, 8 hour, 1 day, 2 day, 4 day and 7 days of reweighting-induced hypertrophy. Muscle mass measurements demonstrated continual loss of soleus mass occurred throughout the 21 days of hindlimb suspension; following reweighting, atrophied soleus muscle mass increased dramatically between 8 hours and 1 day post reweighting. Proteomic analysis of normal and atrophied soleus muscle demonstrated statistically significant changes in the relative levels of 29 soleus proteins. Reweighting following atrophy demonstrated statistically significant changes in the relative levels of 15 soleus proteins. Protein identification using mass spectrometry was attempted for all differentially regulated proteins from both atrophied and hypertrophied soleus muscle. Five differentially regulated proteins from the hindlimb suspended atrophied soleus muscle were identified while five proteins were identified in the reweighting-induced hypertrophied soleus muscles. The identified proteins could be generally grouped together as metabolic proteins, chaperone proteins and contractile apparatus proteins. Together these data demonstrate that coordinated temporally regulated changes in the skeletal muscle proteorne occur during disuse-induced soleus muscle atrophy and reweighting hypertrophy.

Optimized procedures have been developed for the addition of sulfonic acid groups to the N-termini of low-level peptides. These procedures have been applied to peptides produced by tryptic digestion of proteins that have been separated by two-dimensional (2-D) gel electrophoresis. The derivatized peptides were sequenced using matrix-assisted laser desorption/ionization (MALDI) post-source decay (PSD) and electrospray ionization-tandem mass spectrometry methods. Reliable PSD sequencing results have been obtained starting with sub-picomole quantities of protein. We estimate that the current PSD sequencing limit is about 300 fmol of protein in the gel. The PSD mass spectra of the derivatized peptides usually allow much more specific protein sequence database searches than those obtained without derivatization. We also report initial automated electrospray ionization-tandem mass spectrometry sequencing of these novel peptide derivatives. Both types of tandem mass spectra provide predictable fragmentation patterns for arginine-terminated peptides. The spectra are easily interpreted de novo, and they facilitate error-tolerant identification of proteins whose sequences have been entered into databases.

A proteomic analysis was performed comparing normal rat soleus muscle to denervated soleus muscle at 0.5, 1, 2, 4, 6, 8 and 10 days post denervation. Muscle mass measurements demonstrated that the times of major mass changes occurred between 2 and 4 days post denervation. Proteomic analysis of the denervated soleus muscle during the atrophy process demonstrated statistically significant (at the p < 0.01 level) changes in 73 soleus proteins, including coordinated changes in select groups of proteins. Sequence analysis of ten differentially regulated proteins identified metabolic proteins, chaperone and contractile apparatus proteins. Together these data indicate that coordinated temporally regulated changes in the proteome occur during denervation-induced soleus muscle atrophy, including changes in muscle metabolism and contractile apparatus proteins.

We report the application of nanoelectrospray ionization tandem mass spectrometry (nES-MS/MS) and capillary LC/microelectrospray MS/MS (cLC/µES-MS/MS) for sequencing sulfonic acid derivatized tryptic peptides. These derivatives were specifically prepared to facilitate low-energy charge-site-initiated fragmentation of C-terminal arginine-containing peptides, and to enhance the selective detection of a single series of y-type fragment ions. Both singly and doubly protonated peptides were analyzed by MS/MS and the results were compared with those from their derivatized counterparts. Model peptides and peptides from tryptic digests of gel-isolated proteins were analyzed. Derivatized singly protonated peptides fragment in the same way by nES-MS/MS as they do by post-source decay matrix-assisted laser desorption/ionization mass spectrometry (PSD-MALDI-MS). They produce fragment ion spectra dominated by y-ions, and the simplified spectra are readily interpreted de novo. Doubly protonated peptides fragment in much the same way as their non-derivatized doubly protonated counterparts. The fragmentation of doubly protonated derivatives is especially useful for sequencing peptides that possess a proline residue near the N-terminus of the molecule. The singly protonated forms of these proline-containing derivatives often show enhanced fragmentation on the N-terminal side of the proline and considerably reduced fragmentation on the C-terminal side. In addition, sulfonic acid derivatization increases the in-source fragmentation of arginine-containing peptides. This could be useful for sequence verification and sequence tagging for use in single stage mass spectrometry. Copyright © 2000 John Wiley & Sons, Ltd.

We analyzed protein expression in the cytosolic fraction prepared from whole kidneys in male Swiss-Webster mice exposed 1 h/day for five days to aerosolized JP-8 jet fuel at a concentration of 1000 mg/m3, simulating military occupational exposure. Kidney cytosol samples were solubilized and separated via large-scale, high-resolution two-dimensional electrophoresis (2-DE) and gel patterns scanned, digitized and processed for statistical analysis. Significant changes in soluble kidney proteins resulted from jet fuel exposure. Several of the altered proteins were identified by peptide mass finger-printing and related to ultrastructural abnormalities, altered protein processing, metabolic effects, and paradoxical stress protein/detoxification system responses. These results demonstrate a significant but comparatively moderate JP-8 effect on protein expression in the kidney and provide novel molecular evidence of JP-8 nephrotoxicity. Human risk is suggested by these data but conclusive assessment awaits a noninvasive search for biomarkers in JP-8 exposed humans.

We analyzed protein expression in the cytosolic fraction prepared from whole lung tissue in male Swiss-Webster mice exposed 1 h/day for seven days to aerosolized JP-8 jet fuel at concentrations of 1000 and 2500 mg/m3, simulating military occupational exposure. Lung cytosol samples were solubilized and separated via large scale, high resolution two-dimensional electrophoresis (2-DE) and gel patterns scanned, digitized and processed for statistical analysis. Significant quantitative and qualitative changes in tissue cytosol proteins resulted from jet fuel exposure. Several of the altered proteins were identified by peptide mass fingerprinting, confirmed by sequence tag analysis, and related to impaired protein synthetic machinery, toxic/metabolic stress and detoxification systems, ultrastructural damage, and functional responses to CO2 handling, acid-base homeostasis and fluid secretion. These results demonstrate a significant but comparatively moderate JP-8 effect on protein expression and corroborate previous morphological and biochemical evidence. Further molecular marker development and mechanistic inferences from these observations await proteomic analysis of whole tissue homogenates and other cell compartment, i.e., mitochondria, microsomes, and nuclei of lung and other targets.

Penicillin-binding protein 2a (PBP2a), a high molecular mass PBP, is the primary enzyme responsible for the β-lactam resistance in methicillin-resistant Staphylococcus aureus (MRSA). Inhibition of a PBP such as PBP2a by β-lactams is due to covalent modification of an active site serine residue. Based on the sequence alignment with well studied β-lactamases, DD-carboxypeptidases and other high molecular mass PBPs, the serine of a tetrad S403XXK in PBP2a was tentatively identified as the penicillin-binding site. However, direct evidence for the involvement of serine403 has not been reported. In this study, a method which combines liquid chromatography/electrospray mass spectrometry (LC/MS) and nano-electrospray MS for the identification of the active site serine in PBP2a is described. The covalent binding of the β-lactams was carried out in vitro with the recombinant PBP2a. Peptide mapping of the cyanogen bromide fragments from penicilloyl-PBP2a, using microbore LC/MS, provided a rapid identification of the modified peptide with a 334 Da mass increase. The acylated peptide was isolated and further digested with trypsin. Nano-electrospray MS/MS sequencing of the acylated peptide in the tryptic digest showed that the penicillin was indeed attached to serine403. © 1998 John Wiley & Sons, Ltd.