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The sites and mechanisms of aconitase inactivation by peroxynitrite (ONOO-), a strong oxidant and nitrating agent readily formed from superoxide anion and nitric oxide generated by mitochondria is examined. The mechanisms inherent in aconitase inactivation by ONOO- are discussed in terms of the mitochondrial matrix metabolic and thiol redox state.

The current study examined the stability of several antidoping prohibited substances analytes in urine after 15‐min exposure to UV‐C light in a Biosafety Level 2 cabinet. The urine matrices were exposed within the original antidoping bottles with the aim to destroy DNA/RNA and possible SARS CoV‐2. The analytes small molecules Phase I and Phase II metabolites and peptides, in total 444, endogenous, internal standards, and prohibited substances, pH, and specific gravity in urine were studied. The accredited analytical methods were used by Anti‐Doping Laboratory Qatar for the comparison of data of the same urine samples analyzed with and without UV‐C exposure. In the study conditions, no problems of stability were detected in the substances spiked in the urine samples exposed in the UV‐C irradiation. [ABSTRACT FROM AUTHOR]

Abstract Background Non-typeable Haemophilus influenzae biofilm formation is implicated in a number of chronic infections including otitis media, sinusitis and bronchitis. Biofilm structure includes cells and secreted extracellular matrix that is "slimy" and believed to contribute to the antibiotic resistant properties of biofilm bacteria. Components of biofilm extracellular matrix are largely unknown. In order to identify such biofilm proteins an ex-vivo biofilm of a non-typeable Haemophilus influenzae isolate, originally from an otitis media patent, was produced by on-filter growth. Extracellular matrix fraction was subjected to proteomic analysis via LC-MS/MS to identify proteins. Results 265 proteins were identified in the extracellular matrix sample. The identified proteins were analyzed for COG grouping and predicted cellular location via the TMHMM and SignalP predictive algorithms. The most over-represented COG groups identified compared to their frequency in the Haemophilus influenzae genome were cell motility and secretion (group N) followed by ribosomal proteins of group J. A number of hypothetical or un-characterized proteins were observed, as well as proteins previously implicated in biofilm function. Conclusion This study represents an initial approach to identifying and cataloguing numerous proteins associated with biofilm structure. The approach can be applied to biofilms of other bacteria to look for commonalities of expression and obtained information on biofilm protein expression can be used in multidisciplinary approaches to further understand biofilm structure and function.

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Abstract: The main purpose of this article is to show the application of the CG/C/IRMS in real time during competition in the steroid confirmation analysis. For this reason, this paper summarizes the results obtained from the doping control analysis during the period of the 2007 Pan American Games held in Rio de Janeiro, Brazil. Approximately 5600 athletes from 42 different countries competed in the games. Testing was performed in accordance to World Anti-Doping Agency (WADA) technical note for prohibited substances. This paper reports data where abnormal urinary steroid profiles, have been found with the screening procedures. One 8mL urine sample was used for the analysis of five steroid metabolites with two separate analyses by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). Urine samples were submitted to GC/C/IRMS for confirmation analysis to determine the 13C/12C ratio of selected steroids. Fifty-seven urine samples were analyzed by GC/C/IRMS and the δ 13C values (‰) of androsterone, etiocholanolone, 5β-androstane-3α, 17β-diol (5β-diol), 5α-androstane-3α, 17β-diol (5α-diol) and 5β-pregnane-3α, 20α-diol (5β-pdiol), the endogenous reference compound are presented. One urine sample with a testosterone/epitestosterone (T/E) ratio of 4.7 was confirmed to be positive of doping by GC/C/IRMS analysis. The δ values of 5β-diol and 5α-diol were 3.8 and 10.8, respectively, compared to the endogenous reference compound 5β-pdiol, which exceeded the WADA limit of 3‰. The results obtained by CG/C/IRMS confirmation analyses, in suspicious samples, were conclusive in deciding whether or not a doping steroid violation had occurred. [Copyright &y& Elsevier]

Background: Non-typeable Haemophilus influenzae biofilm formation is implicated in a number of chronic infections including otitis media, sinusitis and bronchitis. Biofilm structure includes cells and secreted extracellular matrix that is "slimy" and believed to contribute to the antibiotic resistant properties of biofilm bacteria. Components of biofilm extracellular matrix are largely unknown. In order to identify such biofilm proteins an ex-vivo biofilm of a non-typeable Haemophilus influenzae isolate, originally from an otitis media patent, was produced by on-filter growth. Extracellular matrix fraction was subjected to proteomic analysis via LC-MS/MS to identify proteins. Results: 265 proteins were identified in the extracellular matrix sample. The identified proteins were analyzed for COG grouping and predicted cellular location via the TMHMM and SignalP predictive algorithms. The most over-represented COG groups identified compared to their frequency in the Haemophilus influenzae genome were cell motility and secretion (group N) followed by ribosomal proteins of group J. A number of hypothetical or un-characterized proteins were observed, as well as proteins previously implicated in biofilm function. Conclusion: This study represents an initial approach to identifying and cataloguing numerous proteins associated with biofilm structure. The approach can be applied to biofilms of other bacteria to look for commonalities of expression and obtained information on biofilm protein expression can be used in multidisciplinary approaches to further understand biofilm structure and function. [ABSTRACT FROM AUTHOR]