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The article offers information on Comprehensive Care for Joint Replacement model for helping orthopedic surgeons in lower extremity hip and knee joint replacements. It mentions that the model was designed to more efficiently care for beneficiaries by examining bundle payment and quality measurement for an episode of care while encouraging coordination of care from the preoperative visit through recovery.

Enrollment of children into pediatric clinical trials remains challenging. More effective strategies to improve recruitment of children into trials are needed. This study used in-depth qualitative interviews with parents who were approached to enroll their children in a clinical trial in order to gain an understanding of the barriers to pediatric clinical trial participation.

A clinical case report is presented on a 76-year-old man who volunteered for a 3.0 T magnetic resonance (MR) carotid protocol. The subject was referred for carotid endarterectomy and histology was performed on the ex vivo specimen and compared with the in vivo images.

A cardiac imaging pilot study was performed on 1.5 and 3.0 Tesla (T) whole body magnetic resonance units equipped with identical gradient sets and geometrically equivalent body coils. The goals were to compare the signal-to-noise (SNR) and contrast-to-noise (CNR) ratios on matched studies conducted at both field strengths and demonstrate the potential for functional and morphologic cardiac evaluation at 3.0 T.

In this work, we demonstrate and characterize a large-volume radiofrequency (RF) coil insert used to perform human torso magnetic resonance imaging at 3 T. The coil is a transmission line resonator of elliptic cross-section that can be actively detuned for operation with localized receive-only surface coils. The coil fits within the 55 cm inner bore liner of a 3 T whole body imager and accommodates small- to medium-sized torsos. Sixteen flat transmission line elements are used; each is 32 cm in length and composed of multiple microstrip capacitors spaced equally inside the elliptic shield (52 cm and 40 cm major and minor axes, respectively). A four-port electrical drive was used to improve B1 homogeneity and power efficiency. The power required for a 90° 2 ms single side-lobe sinc pulse for the chest loaded coil was less than 2 kW. Active detuning for operation with receive-only surface coils was achieved by placement of a low-voltage PIN diode network on each individual transmission line element. A quadrature pair of 10 × 15 cm² rectangular surface coils with active detuning traps was used for high spatial resolution cardiac and spine imaging. Since the coil is completely portable, any anatomical region of interest may be centered within the active volume. The head loaded coil required less power and enabled the use of standard 180° pulses well within specific absorption rate limits. Occipital lobe images using a receive-only quadrature 8 cm loop surface coil pair are also presented. As the number of high-field whole body systems increases, an RF coil insert optimized for the torso provides an economical and efficient strategy for extending the capabilities of these systems beyond neuroimaging. © 2002 Wiley Periodicals, Inc. Concepts in Magnetic Resonance (Magn Reson Engineering) 15: 92–100, 2002.

Measurement of the EEG during fMRI scanning can give rise to image distortions due to magnetic susceptibility, eddy currents or chemical shift artifacts caused by certain types of EEG electrodes, cream, leads, or amplifiers. Two different creams were tested using MRS and T2* measurements, and we found that the one with higher water content was superior. This study introduces an index that quantifies the influence of EEG equipment on the BOLD fMRI signal. This index can also be used more generally to measure the changes in the fMRI signal due to the presence of any type of device inside (or outside) of the field of view (e.g., with fMRI and diffuse optical tomography, infrared imaging, transcranial magnetic stimulation, ultrasound imaging, etc.). Quantitative noise measurements are hampered by the normal variability of functional activation within the same subject and by the different slice profiles obtained when inserting a subject multiple times inside a MR imaging system. Our measurements account for these problems by using a matched filtering of cortical surface maps of functional activations. The results demonstrate that the BOLD signal is not influenced by the presence of EEG electrodes when using a properly constructed MRI compatible recording cap. Hum. Brain Mapping 14:108–115, 2001. © 2001 Wiley‐Liss, Inc.

We have investigated the transfer of polarization from 129Xe to solute protons in aqueous solutions to determine the feasibility of using hyperpolarized xenon to enhance 1H sensitivity in aqueous systems at or near room temperatures. Several solutes, each of different molecular weight, were dissolved in deuterium oxide and although large xenon polarizations were created, no significant proton signal enhancement was detected in l-tyrosine, α-cyclodextrin, β-cyclodextrin, apomyoglobin, or myoglobin. Solute-induced enhancement of the 129Xe spin–lattice relaxation rate was observed and depended on the size and structure of the solute molecule. The significant increase of the apparent spin–lattice relaxation rate of the solution phase 129Xe by α-cyclodextrin and apomyoglobin indicates efficient cross relaxation. The slow relaxation of xenon in β-cyclodextrin and l-tyrosine indicates weak coupling and inefficient cross relaxation. Despite the apparent cross-relaxation effects, all attempts to detect the proton enhancement directly were unsuccessful. Spin–lattice relaxation rates were also measured for Boltzmann 129Xe in myoglobin. The cross-relaxation rates were determined from changes in 129Xe relaxation rates in the α-cyclodextrin and myoglobin solutions. These cross-relaxation rates were then used to model 1H signal gains for a range of 129Xe to 1H spin population ratios. These models suggest that in spite of very large 129Xe polarizations, the 1H gains will be less than 10% and often substantially smaller. In particular, dramatic 1H signal enhancements in lung tissue signals are unlikely.

Using a new method of xenon laser‐polarization that permits the generation of liter quantities of hyperpolarized 129Xe gas, the first 129Xe imaging results from the human chest and the first 129Xe spectroscopy results from the human chest and head have been obtained. With polarization levels of approximately 2%, cross‐sectional images of the lung gas‐spaces with a voxel volume of 0.9 cm3(signal‐to‐noise ratio (SNR), 28) were acquired and three dissolved‐phase resonances in spectra from the chest were detected. In spectra from the head, one prominent dissolved‐phase resonance, presumably from brain parenchyma, was detected. With anticipated improvements in the 129Xe polarization system, pulse sequences, RF coils, and breathing maneuvers, these results suggest the possibility for 129Xe gas‐phase imaging of the lungs with a resolution approaching that of current conventional thoracic proton imaging. Moreover, the results suggest the feasibility of dissolved‐phase imaging of both the chest and brain with a resolution similar to that obtained with the gas‐phase images.

Charged phospholipid vesicles were characterized at low ionic strengths by means of pulsed field gradient NMR and scanning electron microscopy for use as model systems for electrokinetic studies. Vesicles containing dioleoylphosphatidylglycerol (DOPG) and 1-palmitoyl-2-oleoyl phosphatidylcholine (POPC) in a molar ratio of 1:4 with 250 mM sucrose and neutral pH but no added salt were found to be unstable and to have diffusion coefficients unrelated to the 0.1- or 0.2-µm filter pore sizes used in their preparation. Scanning electron microscopy showed giant multilamellar structures and aggregates for this vesicle system. In contrast, neutral vesicles containing only POPC exhibited average sizes comparable to the filter pore sizes and electron micrographs with mainly normal unilamellar structures. It was also found that charged vesicles prepared with dilauroylphosphatidylglycerol (DLPG) and either dilauroylphosphatidylcholine (DLPC) or egg phosphatidylcholine (EPC) at 1:4 molar ratio were well behaved and stable. Why the short-chained DLPG (saturated C₁₂ chains, 12:0) enhances stability compared with DOPG is not clear. The distribution of electrophoretic mobilities for unilamellar, 0.1 µm DLPG/ EPC (1:4) vesicles was determined by electrophoretic NMR. Copyright 1995, 1999 Academic Press

The US Food and Drug Administration (FDA) is developing a new framework to provide patients with quality, up-to-date prescription product information that will promote the safe use of prescribed medication. The goal of this new Patient Medication Information is to provide patient-oriented information for each prescription product. Described in this article are the efforts of the FDA to help ensure that patients receive essential prescription medication information.

The US Food and Drug Administration (FDA) is developing a new framework to provide patients with quality, up-to-date prescription product information that will promote the safe use of prescribed medication. The goal of this new Patient Medication Information is to provide patient-oriented information for each prescription product. Described in this article are the efforts of the FDA to help ensure that patients receive essential prescription medication information.

Sample mislabeling or misannotation has been a long-standing problem in scientific research, particularly prevalent in large-scale, multi-omic studies due to the complexity of multi-omic workflows. There exists an urgent need for implementing quality controls to automatically screen for and correct sample mislabels or misannotations in multi-omic studies. Here, we describe a crowdsourced precisionFDA NCI-CPTAC Multi-omics Enabled Sample Mislabeling Correction Challenge, which provides a framework for systematic benchmarking and evaluation of mislabel identification and correction methods for integrative proteogenomic studies. The challenge received a large number of submissions from domestic and international data scientists, with highly variable performance observed across the submitted methods. Post-challenge collaboration between the top-performing teams and the challenge organizers has created an open-source software, COSMO, with demonstrated high accuracy and robustness in mislabeling identification and correction in simulated and real multi-omic datasets.

To address a critical roadblock that can occur in translational and clinical research, the National Cancer Institute and the Food and Drug Administration, in coordination with the DREAM Challenges, are launching the first computational challenge using multi-omics datasets to detect and correct specimen mislabeling.