Arrhythmogenic atrial remodeling during pregnancy in mice.

Background: Pregnancy is associated with greater vulnerability to supraventricular tachyarrhythmias.

Objective: As the underlying mechanisms remain to be elucidated, we investigated whether pregnancy induces atrial remodeling that might contribute to this.

Methods: Atrial electrophysiological and contractile properties were examined in nonpregnant and pregnant (P) mice.

Cardiac automaticity is modulated by IKACh in sinoatrial node during pregnancy.

Aims: Pregnant women have a significantly elevated resting heart rate (HR), which makes cardiac arrhythmias more likely to occur. Although electrical remodeling of the sinoatrial node (SAN) has been documented, the underlying mechanism is not fully understood. The acetylcholine-activated potassium current (IKACh), one of the major repolarizing currents in the SAN, plays a critical role in HR control by hyperpolarizing the maximal diastolic potential (MDP) of the SAN action potential (AP), thereby reducing SAN automaticity and HR.

Patient-partner engagement at the Centre de recherche du CHUS in the Province of Québec, Canada: from an intuitive methodology to outreach after three years of implementation.

Background: Medical societies and funding agencies strongly recommend that patients be included as partners in research publications and grant applications. Although this "top-down" approach is certainly efficient at forcing this new and desirable type of collaboration, our past experience demonstrated that it often results in an ambiguous relationship as not yet well integrated into the cultures of either patients' or the researchers'. The question our group raised from this observation was: "How to generate a cultural shift toward a fruitful and long-lasting collaboration between patients and researchers? A "bottom-up" approach was key to our stakeholders.

A Bioactive Coating Enhances Bone Allografts in Rat Models of Bone Formation and Critical Defect Repair.

Bone allografts are inferior to autografts for the repair of critical-sized defects. Prior studies have suggested that bone morphogenetic protein-2 (BMP-2) can be combined with allografts to produce superior healing. We created a bioactive coating on bone allografts using polycondensed deoxyribose isobutyrate ester (PDIB) polymer to deliver BMP-2 ± the bisphosphonate zoledronic acid (ZA) and tested its ability to enhance the functional utility of allografts in preclinical Wistar rat models.

A Longitudinal Low Dose μCT Analysis of Bone Healing in Mice: A Pilot Study.

Low dose microcomputed tomography (μCT) is a recently matured technique that enables the study of longitudinal bone healing and the testing of experimental treatments for bone repair. This imaging technique has been used for studying craniofacial repair in mice but not in an orthopedic context. This is mainly due to the size of the defects (approximately 1.

BMP-9 expression in human traumatic heterotopic ossification: a case report.

Background: Heterotopic ossification (HO) is defined as the abnormal formation of mature bone in soft tissue, notably skeletal muscle. The morbidity of HO in polytraumatized patients impacts the functional outcome, impairs rehabilitation, and increases costs due to subsequent surgical interventions.

Case Presentation: We present the case of a 34-year-old African male who developed severe HO around his right hip 11 days after a major trauma.

The evaluation of ectopic bone formation induced by delivery systems for bone morphogenetic protein-9 or its derived peptide.

We have earlier shown that a peptide derived from the bone morphogenetic protein-9 (pBMP-9) stimulates mouse preosteoblasts MC3T3-E1 differentiation in vitro. Here, we evaluated the effects of two delivery systems (DSs) for pBMP-9, one based on collagen and the other on chitosan. The release kinetics of BMP-9 (used as control) and pBMP-9 from these DSs were first determined in vitro by using enzyme-linked immunosorbent assay and high performance liquid chromatography assays, respectively.

The proteasome inhibitor MG132 reduces immobilization-induced skeletal muscle atrophy in mice.

Background: Skeletal muscle atrophy is a serious concern for the rehabilitation of patients afflicted by prolonged limb restriction. This debilitating condition is associated with a marked activation of NFκB activity. The ubiquitin-proteasome pathway degrades the NFκB inhibitor IκBα, enabling NFκB to translocate to the nucleus and bind to the target genes that promote muscle atrophy.

BMP-9-induced muscle heterotopic ossification requires changes to the skeletal muscle microenvironment.

Heterotopic ossification (HO) is defined as the formation of bone inside soft tissue. Symptoms include joint stiffness, swelling, and pain. Apart from the inherited form, the common traumatic form generally occurs at sites of injury in damaged muscles and is often associated with brain injury.