This operon plays an important role in biofilm formation in Escherichia
coli. However, its cellular function has remained unknown. Here, we found that 1 base downstream of mqsR there is a gene, ygiT, that is co-transcribed with mqsR. Induction of mqsR caused cell growth arrest, whereas ygiT co-induction recovered cell growth. We demonstrate that MqsR (98 amino acid residues), which has no homology to the well characterized mRNA interferase MazF, is a potent inhibitor of protein synthesis that functions by degrading cellular mRNAs. In vivo and in vitro primer extension experiments showed that MqsR is an mRNA interferase specifically cleaving mRNAs at GCU. The mRNA interferase activity of purified MqsR was inhibited by purified YgiT (131 residues). MqsR forms a stable 2: 1 complex with YgiT, and the complex likely functions as a repressor for
the mqsR-ygiT operon by specifically binding to two BMN 673 nmr different palindromic sequences present in the 5′-untranslated region of this operon.”
“This study used an infusion of a paramagnetic contrast agent to perturb intravascular blood susceptibility and investigate its effect on the BOLD hemodynamic response. A three compartment BOLD signal model combined with a modified balloon model was developed to interpret the MR signal. This model incorporated arterial blood volume in order to simulate signal changes resulting from the contrast agent. The BOLD signal model was fitted to the experimental data Selleck Navitoclax to test the hypothesis that arterial blood volume changes during activation. Evofosfamide clinical trial It was found that allowing arterial blood volume to change, rather than assuming this change is negligible as often assumed in the literature, provides a better fit to the experimental data, particularly during the BOLD overshoot. The post-stimulus undershoot was fitted well, regardless of whether the arterial blood volume was allowed to change, by assuming that this feature is due to delayed
venous compliance. However the resultant elevation in post-stimulus blood volume decays with an extremely long time constant, taking more than 55 s to recover to baseline following a 4.8 s stimulus. The post-stimulus signal changes measured here could alternatively be described by a post-stimulus elevation in metabolism. An alternative model of oxygen extraction, in place of the Oxygen Limitation model, would be required to test this hypothesis. (C) 2009 Elsevier Inc. All rights reserved.”
“Objectives. We conducted a study to assess the acute procedural success and the long-term effect of radiofrequency ablation (RFA) for ventricular tachycardia (VT) in patients with ischaemic heart disease. Design. We included 90 patients with ischaemic heart disease treated with RFA for VT in our institution. Data were obtained from patient files, and implantable cardioverter-defibrillator (ICD) discharges were recorded from in-house and remote follow-up data.