Dissecting the kinetics of the NADP(+)-FADH2 charge transfer complex and flavin semiquinones in neuronal nitric oxide synthase.

Electron flow within the neuronal nitric oxide synthase reductase domain (nNOSrd) includes hydride transfer from NADPH to FAD followed by two one-electron transfer reactions from FAD to FMN. We have used stopped flow spectrometry to closely monitor these electron transfer steps for both the wild type and the ΔG810 mutant of nNOSrd using a protocol involving both global analyses of the photodiode array spectral scans and curve fittings of single wavelength kinetic traces. The charge transfer complex and interflavin electron transfer events recorded at 750nm and 600nm, respectively, show the kinetics in different time frames.

Clinical experiences of delayed contrast enhancement with cardiac computed tomography: case series.

Background: Myocardial delayed enhancement (MDE) by gadolinium-enhanced cardiac MRI is well established for myocardial scar assessment in ischemic and non-ischemic heart disease. The role of MDE by cardiac CT (CT-MDE) is not yet defined.

Findings: We reviewed all clinical cases of CT-MDE at a tertiary referral center to present the cases as a case series.

Coronary calcium scan acquisition before coronary CT angiography: limited benefit or useful addition?

Objective: This article reviews the role of coronary calcium quantification in symptomatic patients and the pros and cons of acquiring an unenhanced coronary calcium scan in every patient with suspected coronary artery disease referred for coronary CT angiography.

Conclusion: The acquisition of a coronary calcium scan in every symptomatic patient referred for coronary CT angiography requires a case-by-case approach.

ACR Appropriateness Criteria(®) acute nonspecific chest pain-low probability of coronary artery disease.

This document outlines the usefulness of available diagnostic imaging for patients without known coronary artery disease and at low probability for having coronary artery disease who do not present with classic signs, symptoms, or electrocardiographic abnormalities indicating acute coronary syndrome but rather with nonspecific chest pain leading to a differential diagnosis, including pulmonary, gastrointestinal, or musculoskeletal pathologies. A number of imaging modalities are available to evaluate the broad spectrum of possible pathologies in these patients, such as chest radiography, multidetector CT, MRI, ventilation-perfusion scans, cardiac perfusion scintigraphy, transesophageal and transthoracic echocardiography, PET, spine and rib radiography, barium esophageal and upper gastrointestinal studies, and abdominal ultrasound. It is considered appropriate to start the assessment of these patients with a low-cost, low-risk diagnostic test such as a chest x-ray.

Paradoxical air embolism following contrast material injection through power injectors in patients with a patent foramen ovale.

In patients with a patent foramen ovale, use of air filters during intravenous infusions is common, but they are not compatible with power injection. Therefore we aimed to assess the incidence of paradoxical air embolism on CT of the chest and brain following contrast material injection through a power injector in patients with a patent foramen ovale, without the use of a filter. In this IRB approved, HIPAA compliant retrospective study, two independent radiologists reviewed 289 CT scans of the chest (n = 233) and brain (n = 56) for vascular air embolism following contrast material injection through a power injector in 93 subjects (43 men, mean age 66 y) with a known patent foramen ovale.

Advanced adaptive axial-sequential prospectively electrocardiogram-triggered dual-source coronary computed tomographic angiography in a patient with atrial fibrillation.

Atrial fibrillation is considered a relative contraindication to coronary computed tomographic angiography (CCTA) because image quality and radiation dose-saving measures largely depend on low and stable heart rates. Most published experiences with CCTA during atrial fibrillation have relied on retrospective gating to mitigate artifacts via electrocardiogram editing. However, a large number of patients arrive at the CT suite with irregular heart rates.

Normal magnetic resonance imaging of the thorax.

The soft tissue contrast properties of magnetic resonance (MR) allow excellent discrimination of most intrathoracic structures other than the lungs, and allow good insight into normal anatomy. Using MR imaging, the normal cardiorespiratory system, including portions of the lungs and pleural spaces, as well as the mediastinal, chest wall, and cardiac structures can be well depicted. In addition, using newer MR pulse sequences, dynamic ECG-gated imaging can also be achieved, which allows a window into the normal functional processes of these organs.

Extracardiac findings in cardiac computed tomographic angiography in patients at low to intermediate risk for coronary artery disease.

Purpose: To evaluate the prevalence, clinical significance, interobserver agreement, and follow-up of extracardiac findings on coronary computed tomographic angiography (CTA).

Methods: A prospectively recruited cohort of 80 patients at low to intermediate risk of having coronary artery disease underwent CTA with field of view imaging from lung apices to upper abdomen. Two staff radiologists read each scan independently.

Evaluating the performance of the Global Registry of Acute Coronary Events risk-adjustment index across socioeconomic strata among patients discharged from the hospital after acute myocardial infarction.

Background: Cardiac risk-adjustment indices for acute coronary syndromes have important clinical and research applications, especially if proven to be valid and robust across heterogeneous socioeconomically diverse populations. The objective of this study was to validate the Global Registry of Acute Coronary Events (GRACE) risk-adjustment index for 6-month all-cause mortality across socioeconomic strata.

Methods: The study cohort consisted of patients who were enrolled in the SESAMI study and discharged alive from the hospital between December 1, 1999, and February 28, 2003.

Iroquois genes influence proximo-distal morphogenesis during rat lung development.

Lung development is a highly regulated process directed by mesenchymal-epithelial interactions, which coordinate the temporal and spatial expression of multiple regulatory factors required for proper lung formation. The Iroquois homeobox (Irx) genes have been implicated in the patterning and specification of several Drosophila and vertebrate organs, including the heart. Herein, we investigated whether the Irx genes play a role in lung morphogenesis.

Major trauma in pregnant women during the summer.

Background: Pregnant women represent a major challenge in trauma care because of the risks to both mother and child and because of the difficulties in following standard protocols.

Methods: We analyzed data for all pregnant women admitted to the hospital in Canada over 7 years to test whether major trauma still clustered in the summer despite their aversion toward alcohol, recklessness, and extreme sports.

Results: A total of 2,618 pregnant women sustained major trauma.