Objectives: The aim of this study is to assess the utility of optical coherence tomography (OCT) in patients with exercise-related acute coronary syndrome (ACS) presenting with inconclusive angiographic findings.
Background: Regular physical activity reduces the incidence of cardiovascular events. Nevertheless, the risk of ACS or sudden cardiac death (SCD) increases during sport.
Proc Natl Acad Sci U S A
December 2018
Hydrogen peroxide (HO) is a strong oxidant capable of oxidizing cysteinyl thiolates, yet only a few cysteine-containing proteins have exceptional reactivity toward HO One such example is the prokaryotic transcription factor OxyR, which controls the antioxidant response in bacteria, and which specifically and rapidly reduces HO In this study, we present crystallographic evidence for the HO-sensing mechanism and HO-dependent structural transition of OxyR by capturing the reduced and HO-bound structures of a serine mutant of the peroxidatic cysteine, and the full-length crystal structure of disulfide-bonded oxidized OxyR. In the HO-bound structure, we pinpoint the key residues for the peroxidatic reduction of HO, and relate this to mutational assays showing that the conserved active-site residues T107 and R278 are critical for effective HO reduction. Furthermore, we propose an allosteric mode of structural change, whereby a localized conformational change arising from HO-induced intramolecular disulfide formation drives a structural shift at the dimerization interface of OxyR, leading to overall changes in quaternary structure and an altered DNA-binding topology and affinity at the catalase promoter region.
View Article and Find Full Text PDFThe gene encodes an oxidoreductase enzyme annotated as DsbA. It has a CPWC active-site motif embedded within its thioredoxin fold domain and mediates the activation of the prodrug TP053, a thienopyrimidine derivative that kills both replicating and nonreplicating bacilli. However, its mode of action and actual enzymatic function in have remained enigmatic.
View Article and Find Full Text PDFArsenic (As) is widespread in the environment and highly toxic. It has been released by volcanic and anthropogenic activities and causes serious health problems worldwide. To survive arsenic-rich environments, soil and saprophytic microorganisms have developed molecular detoxification mechanisms to survive arsenic-rich environments, mainly by the enzymatic conversion of inorganic arsenate (As) to arsenite (As) by arsenate reductases, which is then extruded by arsenite permeases.
View Article and Find Full Text PDFSubcritical water was employed to fractionate woody biomass into carbohydrates and lignin. Nine urban trees species (hardwood and softwood) from Spain were studied. The experiments were carried out in a semi-continuous reactor at 250 °C for 64 min.
View Article and Find Full Text PDFAcute coronary syndromes due to involvement of the left main trunk usually present with subtotal occlusion and electrocardiographic pattern with predominant ST depression (non-ST-elevation myocardial infarction). The cases with complete occlusion frequently present an ST-elevation myocardial infarction pattern, but these patients usually die before reaching the hospital. We present a series of 7 patients with total left main trunk occlusion without collateral circulation showing ST-elevation myocardial infarction pattern.
View Article and Find Full Text PDFIntroduction And Objectives: To determine whether long-term prognosis is affected by myocardial damage taking place during percutaneous coronary intervention (PCI).
Methods: The study included consecutive patients undergoing PCI. Those with elevated baseline cardiac marker levels were excluded.