Combined T -preparation and multidimensional outer volume suppression for coronary artery imaging with 3D cones trajectories.

Purpose: To develop a modular magnetization preparation sequence for combined T -preparation and multidimensional outer volume suppression (OVS) for coronary artery imaging.

Methods: A combined T -prepared 1D OVS sequence with fat saturation was defined to contain a 90° 180° composite nonselective tip-down pulse, two 180° hard pulses for refocusing, and a -90° spectral-spatial sinc tip-up pulse. For 2D OVS, 2 modules were concatenated, selective in X and then Y.

Deep residual network for off-resonance artifact correction with application to pediatric body MRA with 3D cones.

Purpose: To enable rapid imaging with a scan time-efficient 3D cones trajectory with a deep-learning off-resonance artifact correction technique.

Methods: A residual convolutional neural network to correct off-resonance artifacts (Off-ResNet) was trained with a prospective study of pediatric MRA exams. Each exam acquired a short readout scan (1.

Application of maximum bubble pressure surface tensiometer to study protein-surfactant interactions.

Binding of a surfactant to proteins can affect their physicochemical stability and solubility in a formulation. The extent of the effect depends on the binding stoichiometry. In this study, we have utilized the technique of maximum bubble pressure surface tensiometry to characterize the binding between human serum albumin (HSA) and surfactants (sodium dodecyl sulfate (SDS) and polysorbate 80) by dynamic surface tension measurements.

Ultrasonic rheology of a monoclonal antibody (IgG2) solution: implications for physical stability of proteins in high concentration formulations.

The purpose of this work was to investigate if physical stability of a model monoclonal antibody (IgG(2)), as determined by extent of aggregation, was related to rheology of its solutions. Storage stability of the model protein was assessed at 25 degrees C and 37 degrees C for three months in solutions ranging from pH 4.0 to 9.

Evaluation of the iCE280 Analyzer as a potential high-throughput tool for formulation development.

The iCE280 Analyzer (iCE280) was evaluated for its potential application as a high-throughput tool to determine pI and separate charge related species using glycosylated, non-glycosylated and pegylated protein therapeutics as models. Resolution was achieved for glycosylated and non-glycosylated molecules, but remained a challenge for pegylated proteins. The sources of charge variants were determined to be the presence of C-terminal lysine residues, sialic acid content, and deamidation.

Ultrasonic storage modulus as a novel parameter for analyzing protein-protein interactions in high protein concentration solutions: correlation with static and dynamic light scattering measurements.

The purpose of this work was to establish ultrasonic storage modulus (G') as a novel parameter for characterizing protein-protein interactions (PPI) in high concentration protein solutions. Using an indigenously developed ultrasonic shear rheometer, G' for 20-120 mg/ml solutions of a monoclonal antibody (IgG(2)), between pH 3.0 and 9.

Antibody structure, instability, and formulation.

The number of therapeutic monoclonal antibody in development has increased tremendously over the last several years and this trend continues. At present there are more than 23 approved antibodies on the US market and an estimated 200 or more are in development. Although antibodies share certain structural similarities, development of commercially viable antibody pharmaceuticals has not been straightforward because of their unique and somewhat unpredictable solution behavior.

Application of high-frequency rheology measurements for analyzing protein-protein interactions in high protein concentration solutions using a model monoclonal antibody (IgG2).

The purpose of this work was to explore the utilization of high-frequency rheology analysis for assessing protein-protein interactions in high protein concentration solutions. Rheology analysis of a model monoclonal immunoglobulin G2 solutions was conducted on indigenously developed ultrasonic shear rheometer at frequency of 10 MHz. Solutions at pH 9.

Protein structural conformation and not second virial coefficient relates to long-term irreversible aggregation of a monoclonal antibody and ovalbumin in solution.

Purpose: The purpose of the study was to investigate the relationship of the second virial coefficient, B22, to the extent of irreversible protein aggregation upon storage.

Methods: A monoclonal antibody and ovalbumin were incubated at 37 degrees C (3 months) under various solution conditions to monitor the extent of aggregation. The B22 values of these proteins were determined under similar solution conditions by a modified method of flow-mode static light scattering.

Retrospective statistical analysis of lyophilized protein formulations of progenipoietin using PLS: determination of the critical parameters for long-term storage stability.

Although certain criteria have become recognized as being essential for a stable lyophilized formulation, the relative importance of different stability criteria has not been demonstrated quantitatively. This study uses multivariate statistical methods to determine the relative importance of certain formulation variables that affect long-term storage stability of a therapeutic protein. Using the projection to latent structures (PLS) method, a retrospective analysis was conducted of 18 formulations of progenipoietin (ProGP), a potential protein therapeutic agent.

Purification and characterization of progenipoietins produced in Escherichia. coli.

The progenipoietins (ProGPs) are a family of genetically engineered chimeric proteins that contain receptor agonist activity for both fetal liver tyrosine kinase-3 and the granulocyte colony-stimulating factor receptor. These unique proteins have previously been shown to induce the proliferation of multiple cell lineages. The characterization of two progenipoietins, ProGP-1 and ProGP-4, refolded and purified from an Escherichia coli expression system is described.