Intraoperative Management of Tracheal Cautery Injury in a Post-Bypass Cardiac Surgery Patient.

We present the case of a tracheal injury that occurred during a Maze procedure performed via sternotomy that was not initially detected by ventilator air leak, but rather by the visual presence of gas bubbles escaping the trachea during chest irrigation. Careful investigation and machine check did reveal a subsequent air leak that would have otherwise been overlooked. Furthermore, the use of intraoperative bronchoscopy was essential in guiding and confirming surgical repair. This case underscores the need for ongoing vigilance and suggests the utility of chest irrigation with Valsalva maneuvers after procedures performed in the vicinity of the trachea to exclude injury.

A Hidden Culprit Illuminated with Advanced Cardiac Imaging.

This case demonstrates the complementary benefit of utilizing multimodality cardiac imaging in the assessment of myocardial infarction with nonobstructive coronary artery disease especially when a culprit lesion is not discovered upon initial coronary catheterization. Use of cardiac magnetic resonance imaging, optical coherence tomography, and invasive coronary angiography together solidified the diagnosis of unstable, complex coronary artery disease in this case.

Non-invasive, in vivo monitoring of neuronal transport impairment in a mouse model of tauopathy using MEMRI.

The impairment of axonal transport by overexpression or hyperphosphorylation of tau is well documented for in vitro conditions; however, only a few studies on this phenomenon have been conducted in vivo, using invasive procedures, and with contradictory results. Here we used the non-invasive, Manganese-Enhanced Magnetic Resonance Imaging technique (MEMRI), to study for the first time a pure model of tauopathy, the JNPL3 transgenic mouse line, which overexpresses a mutated (P301L) form of the human tau protein. We show progressive impairment in neuronal transport as tauopathy advances. These findings are further supported by a significant correlation between the severity of the impairment in neuronal transport assessed by MEMRI, and the degree of abnormal tau assessed by histology. Unlike conventional techniques that focus on axonal transport measurement, MEMRI can provide a global analysis of neuronal transport, i.e. from dendrites to axons and at the macroscopic scale of fiber tracts. Neuronal transport impairment has been shown to be a key pathogenic process in Alzheimer's disease and numerous other neurodegenerative disorders. Hence, MEMRI provides a promising set of functional biomarkers to be used during preclinical trials to facilitate the selection of new drugs aimed at restoring neuronal transport in neurodegenerative diseases.

Quantification of the plasma clearance kinetics of a gadolinium-based contrast agent by photoinduced triplet harvesting.

The use of gadolinium-based contrast agents (GBCA) is integral to the field of diagnostic magnetic resonance imaging (MRI). Pharmacokinetic evaluation of the plasma clearance of GBCA is required for all new agents or improved formulations, to address concerns over toxicity or unforeseen side effects. Current methods to measure GBCA in plasma lack either a rapid readout or the sensitivity to measure small samples or require extensive processing of plasma, all obstacles in the development and characterization of new GBCA. Here, we quantify the plasma concentration of a labeled analogue of a common clinical GBCA by ligand triplet harvesting and energy transfer. The nonemittive GBCA becomes a "dark donor" to a fluorescent detector molecule, with a lower limit of detection of 10(-7) M in unprocessed plasma. On a time scale of minutes, we determine the plasma clearance rate in the wild-type mouse, using time-resolved fluorescence on a standard laboratory plate reader.