Intraventricular conduction delays as a predictor of mortality in acute coronary syndromes.

Aims: Initial proof suggests that a non-specific intraventricular conduction delay (NIVCD) is a risk factor for mortality. We explored the prognosis of intraventricular conduction delays (IVCD)-right bundle branch block (RBBB), left bundle branch block (LBBB), and the lesser-known NIVCD-in patients with acute coronary syndrome (ACS).

Methods And Results: This is a retrospective registry analysis of 9749 consecutive ACS patients undergoing coronary angiography and with an electrocardiographic (ECG) recording available for analysis (2007-18).

Pre-steady-state kinetics and solvent isotope effects support the "billiard-type" transport mechanism in Na -translocating pyrophosphatase.

Membrane-bound pyrophosphatase (mPPase) found in microbes and plants is a membrane H pump that transports the H ion generated in coupled pyrophosphate hydrolysis out of the cytoplasm. Certain bacterial and archaeal mPPases can in parallel transport Na via a hypothetical "billiard-type" mechanism, also involving the hydrolysis-generated proton. Here, we present the functional evidence supporting this coupling mechanism.

High-risk ECG patterns in ST elevation myocardial infarction for mortality prediction.

Aim: We explored the pre-intervention (first medical contact) electrocardiographic (ECG) patterns and their relation to survival among patients with acute myocardial infarction, who presented either with ST elevation (ST elevation myocardial infarction, STEMI) or LBBB, and who underwent emergent coronary angiography in a region with a 24/7/365 STEMI network.

Methods: This is a retrospective analysis of 1363 consecutive patients hospitalized for first STEMI between the years 2014 and 2018. We assessed the prognostic significance of a variety of ECG categories, including location of ST elevation, severity of ischemia, intraventricular and atrioventricular conduction disorders, atrial fibrillation or flutter, junctional rhythms, heart rate, left ventricular hypertrophy and Q waves.

The tetrameric structure of nucleotide-regulated pyrophosphatase and its modulation by deletion mutagenesis and ligand binding.

A quarter of prokaryotic Family II inorganic pyrophosphatases (PPases) contain a regulatory insert comprised of two cystathionine β-synthase (CBS) domains and one DRTGG domain in addition to the two catalytic domains that form canonical Family II PPases. The CBS domain-containing PPases (CBS-PPases) are allosterically activated or inhibited by adenine nucleotides that cooperatively bind to the CBS domains. Here we use chemical cross-linking and analytical ultracentrifugation to show that CBS-PPases from Desulfitobacterium hafniense and four other bacterial species are active as 200-250-kDa homotetramers, which seems unprecedented among the four PPase families.

Residue Network Involved in the Allosteric Regulation of Cystathionine β-Synthase Domain-Containing Pyrophosphatase by Adenine Nucleotides.

Inorganic pyrophosphatase containing regulatory cystathionine β-synthase (CBS) domains (CBS-PPase) is inhibited by adenosine monophosphate (AMP) and adenosine diphosphate and activated by adenosine triphosphate (ATP) and diadenosine polyphosphates; mononucleotide binding to CBS domains and substrate binding to catalytic domains are characterized by positive cooperativity. This behavior implies three pathways for regulatory signal transduction - between regulatory and active sites, between two active sites, and between two regulatory sites. Bioinformatics analysis pinpointed six charged or polar amino acid residues of CBS-PPase as potentially important for enzyme regulation.