Mitochondria-localized AMPK responds to local energetics and contributes to exercise and energetic stress-induced mitophagy.

Mitochondria form a complex, interconnected reticulum that is maintained through coordination among biogenesis, dynamic fission, and fusion and mitophagy, which are initiated in response to various cues to maintain energetic homeostasis. These cellular events, which make up mitochondrial quality control, act with remarkable spatial precision, but what governs such spatial specificity is poorly understood. Herein, we demonstrate that specific isoforms of the cellular bioenergetic sensor, 5' AMP-activated protein kinase (AMPKα1/α2/β2/γ1), are localized on the outer mitochondrial membrane, referred to as mitoAMPK, in various tissues in mice and humans.

Individual differences in field independence influence the ability to determine accurate needle angles.

Objective: "Field dependence" is used in cognitive psychology to describe an individual's tendency to be visually distracted by the surrounding environment. Notwithstanding the role of field dependence in contexts in which spatial judgment is important, such as piloting an aircraft, to date, studies linking field dependence to surgical skills have been limited. We evaluated whether field dependence correlates with an ability to anticipate appropriate needle angles in a simulated setting.

Potential role of γδ T cell-derived IL-17 in acute cardiac allograft rejection.

Background: Although αβ T cells are known to participate in the development of acute cardiac allograft rejection, the role of γδ T cells remains poorly understood. We hypothesized that γδ T cells contribute to acute allograft rejection thru interleukin (IL)-17 production.

Methods: Donor hearts from FVB mice (H-2q) were heterotopically transplanted into C57BL/6-wild type (WT) and γδ T cell-deficient (TCRδ-/-) recipient mice (H-2b).

Releasable annuloplasty ring insertion--a novel experimental implantation model.

Objective: Experimental testing of annuloplasty ring (AR) effects requires a control group if the AR is implanted conventionally. Our goal was to develop a reversible AR insertion method that allows for beating heart assessment with and without an AR, providing the ability to evaluate the effects of an AR in the same animal (internal control). We tested the feasibility of this technique in an in vivo ovine model using four-dimensional (4-D) radiopaque marker tracking.

Retrospective analysis of local sensorimotor deficits after radial artery harvesting for coronary artery bypass grafting.

Objectives: The radial artery (RA) has gained widespread acceptance as a conduit for coronary artery bypass. We analyze patient-based data to determine risk factors for long-term upper limb morbidities associated with RA harvest for coronary artery bypass grafting.

Study Design/methods: Between April 1997 and March 2004, a total of 1030 patients underwent RA harvesting for coronary artery bypass grafting for a total of 1704 harvest sites.

Expression of multiple KCNE genes in human heart may enable variable modulation of I(Ks).

Voltage-gated potassium (K(V)) channels are modulated by at least three distinct classes of proteins including the KCNE family of single transmembrane accessory subunits. In the human genome, KCNE proteins are encoded by five genes designated KCNE1 through KCNE5. KCNE1 associates with KCNQ1 in vitro to generate a potassium current closely resembling the slowly activating delayed rectifier (I(Ks)).

Blockade of the extracellular signal-regulated kinase pathway by U0126 attenuates neuronal damage following circulatory arrest.

Objectives: The extracellular signal-regulated kinase pathway of the mitogen-activated protein kinase signal transduction cascade has been implicated in the neuronal and endothelial dysfunction witnessed following cerebral ischemia-reperfusion injury. Extracellular signal-regulated kinase is activated by mitogen-activated protein kinase/extracellular signal-regulated kinase 1/2. We evaluated the ability of a mitogen-activated protein kinase/extracellular signal-regulated kinase 1/2-specific inhibitor (U0126) to block extracellular signal-regulated kinase activation and mitigate ischemic neuronal damage in a model of deep hypothermic circulatory arrest.

Morbidity after procurement of radial arteries in diabetic patients and the elderly undergoing coronary revascularization.

Background: The use of radial arteries for coronary revascularization is increasing. There remain concerns regarding alteration of upper extremity function after radial artery procurement. This study evaluates the functional morbidity in higher risk patients.

Late cardiac reoperation after cardiac transplantation.

Background: The intermediate and long-term results of cardiac transplantation continue to improve. Subsequent cardiac procedures may be required to extend patient survival and protect graft function.

Methods: The medical records of all adult and pediatric cardiac transplant recipients who underwent a subsequent cardiac procedure at our institution were reviewed.