Publications by authors named "Taylor Johnston"

Significant sensitivity improvements have been achieved by utilizing high temperature superconducting (HTS) resonators in nuclear magnetic resonance (NMR) probes. Many nuclei such as C benefit from strong excitation fields which cannot be produced by traditional HTS resonator designs. We investigate the use of double-sided, counter-wound multi-arm spiral HTS resonators with the aim of increasing the excitation field at the required nuclear Larmor frequency for C.

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Nuclear magnetic resonance (NMR) probes using thin-film high temperature superconducting (HTS) resonators offer high sensitivity and are particularly suitable for small-sample applications. We are developing an improved 1.5 mm HTS NMR probe designed for operation at 14.

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The binding affinity between antibiotic ionophores and alkali ions within supported lipid bilayers was evaluated using affinity chromatography. We used zonal elution and frontal analysis methods in nanovolume liquid chromatography to characterize the binding selectivity of the carrier and channel ionophores valinomycin and gramicidin A within different phosphatidylcholine bilayers. Distinct binding sensitivity to the lipid phase, both in affinity and selectivity, is observed for valinomycin, whereas gramicidin is less sensitive to changes in a membrane environment, behavior that is consistent with ion binding occurring within the interior of an established channel.

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The American College of Cardiology, in collaboration with the American Society of Nuclear Cardiology, Heart Rhythm Society, Mended Hearts, North American Society for Cardiovascular Imaging, Society for Cardiovascular Angiography and Interventions, Society for Cardiovascular Computed Tomography, and Society of Nuclear Medicine and Molecular Imaging, recently published a consensus document recommending best practices for the use of ionizing radiation in cardiovascular medicine. With the increase in number and complexity of catheter-based cardiovascular interventions, cardiothoracic anesthesiologists are being requested to consult and provide care for these patients. This review summarizes the salient portions of the consensus document as it pertains to the anesthesiologist.

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New near-infrared rhodamine dyes with large Stokes shifts were developed and applied for sensitive detection of cellular pH changes and fluctuations by incorporating an additional amine group with fused rings into the rhodamine dyes to enhance the electron donating ability of amine groups and improve the spectroscopic properties of the dyes.

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Patients who have undergone complete cavopulmonary anastomosis, the Fontan procedure, have passive venous blood flow from the superior and inferior vena cava into the pulmonary circulation without passing through the right ventricle. Although this procedure is an effective means of palliation, the resultant chronically increased central venous pressure, leads to several types of hepatic dysfunction including chronic congestion, cardiac cirrhosis, and even hepatocellular carcinoma. In this case report, we describe a patient with Fontan-associated hepatocellular carcinoma who successfully underwent a right hepatectomy.

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Objective: To assess the stability of cardiac output, mean arterial pressure, and systemic vascular resistance during biventricular pacing (BiVP) optimization.

Design: Substudy analysis of data collected as part of a randomized controlled study examining the effects of optimized temporary BiVP after cardiopulmonary bypass (CPB).

Setting: A single-center study at a university-affiliated tertiary care hospital.

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Biventricular pacing (BiVP) can optimize cardiac output (CO) in patients after cardiac surgery, so devices that calculate continuous CO from arterial pressure may be a useful tool. We investigated PulseCO for measuring CO during optimization by comparison with aortic flow probe measurement. Seven patients in the Biventricular Pacing After Cardiac Surgery (BiPACS) trial were studied.

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The prevailing hierarchical model of cortical sensory processing holds that early processing is specific to individual modalities and that combination of information from different modalities is deferred until higher-order stages of processing. In this paper, we present physiological evidence of multisensory convergence at an early stage of cortical auditory processing. We used multi-neuron cluster recordings, along with a limited sample of single-unit recordings, to determine whether neurons in the macaque auditory cortex respond to cutaneous stimulation.

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