Hydroxychloroquine/Azithromycin Therapy and QT Prolongation in Hospitalized Patients With COVID-19.

Objectives: This study aimed to characterize corrected QT (QTc) prolongation in a cohort of hospitalized patients with coronavirus disease-2019 (COVID-19) who were treated with hydroxychloroquine and azithromycin (HCQ/AZM).

Background: HCQ/AZM is being widely used to treat COVID-19 despite the known risk of QT interval prolongation and the unknown risk of arrhythmogenesis in this population.

Methods: A retrospective cohort of COVID-19 hospitalized patients treated with HCQ/AZM was reviewed.

Protocol driven periprocedural anticoagulation for left atrial ablation.

Introduction: A weight-based heparin dosing policy adjusted for preprocedural oral anticoagulation was implemented to reduce the likelihood of subtherapeutic dosing during left atrial catheter ablation procedures. We hypothesized that initiation of the protocol would result in a greater prevalence of therapeutic activated clotting time (ACT) values and decreased time to therapeutic ACT during left atrial ablation procedures.

Methods: A departmental protocol was initiated for which subjects received intravenous unfractionated heparin (UFH) to achieve and maintain a goal of ACT >300 s.

Pulsed field ablation for pulmonary vein isolation in the treatment of atrial fibrillation.

Pulsed-field ablation (PFA) is a promising new ablation modality for the treatment of atrial fibrillation. This energy form employs a train of microsecond duration high amplitude electrical pulses that ablate myocardium by electroporation of the sarcolemmal membrane without measurable tissue heating. The ablation pulse waveform has multiple variable components that can affect ablation efficacy, thus each proprietary system has unique properties that cannot be generalized to other systems.

Synthesis, DNA-PK inhibition, anti-platelet activity studies of 2-(N-substituted-3-aminopyridine)-substituted-1,3-benzoxazines and DNA-PK and PI3K inhibition, homology modelling studies of 2-morpholino-(7,8-di and 8-substituted)-1,3-benzoxazines.

A number of new 2-(pyridin-3-ylamino)-4H-(substituted) benz[e]-1,3-oxazin-4-ones were synthesized 10a-g. These were then reacted with the hydro-halogen salt of 2, 3 and 4-(halo-methyl) pyridine in the presence of Cs(2)CO(3) to give eighteen new 2-(N-substituted (pyridin-3-ylmethyl) amino)-substituted-1,3-benzoxazines (compounds 11a-i, 13a-c, and 15a-f). X-ray crystallography was used to confirm that the 2-N-substituted structures 11 and 13 were formed rather than the 3-N-substitution analogues 12 and 14.

Autophagic death of adult hippocampal neural stem cells following insulin withdrawal.

Novel therapeutic approaches using stem cell transplantation to treat neurodegenerative diseases have yielded promising results. However, survival of stem cells after transplantation has been very poor in animal models, and considerable efforts have been directed at increasing the viability of engrafted stem cells. Therefore, understanding the mechanisms that regulate survival and death of neural stem cells is critical to the development of stem cell-based therapies.

IFN-gamma amplifies NFkappaB-dependent Neisseria meningitidis invasion of epithelial cells via specific upregulation of CEA-related cell adhesion molecule 1.

Temporal relationship between viral and bacterial infections has been observed, and may arise via the action of virus-induced inflammatory cytokines. These, by upregulating epithelial receptors targeted by bacteria, may encourage greater bacterial infiltration. In this study, human epithelial cells exposed to interferon-gamma but not tumour necrosis factor-alpha or interleukin 1-beta supported increased meningococcal adhesion and invasion.

Critical determinants of the interactions of capsule-expressing Neisseria meningitidis with host cells: the role of receptor density in increased cellular targeting via the outer membrane Opa proteins.

Neisseria meningitidis capsule is an important virulence determinant required for survival in the blood but is reportedly involved in inhibiting cellular interactions mediated by meningococcal outer membrane adhesins. However, evidence from our previous studies suggested that target receptor density on host cells may determine whether or not capsulate bacteria can adhere via outer membrane proteins such as Opa. To confirm this and evaluate the impact of capsulation on bacterial interactions, we used Opa(+) and Opa(-) derivatives of capsulate and acapsulate meningococcal isolates and transfected cell lines expressing CEACAM1, a receptor targeted by Opa proteins.