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During purification process development of a recombinant therapeutic protein, an endoproteolytic activity endogenous to the Chinese hamster ovary (CHO) cells and leading to degradation at particular hydrophobic amino acid residues (e.g., Phe and Trp) was observed when processing at acidic pH. The presence of residual levels of protease activity in purified protein batches affected the inherent activity of the product when stored as a solution. To develop a robust purification strategy to minimize this undesirable impact, identification and characterization of this protease was essential to ultimately ensure that a solution formulation was stable for many years. A protease was isolated from CHO cell‐free medium (CFM) using a combination of immobilized pepstatin‐A agarose chromatography and size exclusion chromatography (SEC). The isolated protease has significant proteolytic activity at pH ∼ 3 to neutral pH and was identified as cathepsin D by mass spectrometry. Analytical SEC, chip‐based capillary gel electrophoresis, imaged capillary isoelectric focusing (cIEF), and circular dichroism (CD) spectropolarimetry analyses were performed for additional characterization of the protease. The identification and characterization of this protease enabled the development of a robust purification process by implementation of a controlled temperature inactivation unit operation (heat inactivation) that enabled essentially complete inactivation of the protease, resulting in the production of a stable drug product that had not been possible using column chromatography alone. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:120–129, 2018 [ABSTRACT FROM AUTHOR]

The present study derived hypotheses from Kelley's attribution model and recent research (Mitchell and Byrne, 1973) showing jurors' attitudes influence the length of sentences they recommend. Psychiatric nursing students (N=79) were presented with eight hypothetical case histories of convicted drug offenders, and were asked the causes of the offenders' behavior. The traffickers' socio-economic status, consistency of offenses and form of trial (judge or jury) were experimentally manipulated. As predicted the behavior of consistent offenders was attributed to the person himself and subjects recommended more punishment for such individuals. Furthermore, subjects with liberal drug standards recommended less severe punishment for the offenders. Neither the sex nor the locus of control (Rotter, 1966) of the subjects had any significant main effects. Significant form of trial by consistency and drug standard by socio-economic status interactions were found. Legal implications of the research are presented. [ABSTRACT FROM AUTHOR]

This article focuses on the relationship between internal-external locus of control and guilt. This study examined the relationship between internal-external locus of control and guilt. Ss were 65 male and 137 college undergraduates who completed the Rotter I-E scale and the Mosher Hostility and Morality-Conscience Guilt Scales. Results demonstrated that internals reported a higher degree of hostility guilt than externals. Also, females expressed greater hostility and morality-conscience guilt than males. Ss were 65 males and 137 females enrolled in undergraduate psychology courses at the University of Manitoba.

This article focuses on psychopathological processes. In an attempt to extend the "nomological network" of the hopelessness dimension, the present research examined the relationship between negative expectancies about the future and two theoretically relevant constructs: generalized expectancies for reinforcement, and depression. The generalized expectancy that behavioral outcomes are contingent upon one's own ability and effort (i.e., internal control) vs. the generalized expectancy that such outcomes are determined by powerful others, luck, chance, or fate (i.e., external control) defines internal-external locus of control.

A new method of freeze-thaw is described using experimental data obtained from freezing of purified rhGH (recombinant human growth hormone). The method is based on freezing protein solutions in rectangular rather than cylindrical containers. It is hypothesized that the change in container geometry allows for linear scale-up of the freeze-thaw operation based on equivalency of temperature-time profile. The hypothesis is tested using freeze-thaw data from a miniature (30 ml) and a 2.4 litre container. Computational fluid dynamics techniques are used to simulate the freeze process and the simulations are compared with experimental results. Protein quality is assessed as a function of freeze conditions using dynamic light scattering, circular CD, size-exclusion and reverse-phase HPLC measurements. The results demonstrate the applicability of the new approach. Freezing of rhGH solution at concentrations of approx. 30 mg/ml is shown to be possible with no damage to the molecule for up to five cycles of freeze-thaw. A nitrogen blast chest-freezer is designed and evaluated as part of the process. The refrigeration system and the freeze-thaw method can be used to freeze-thaw bulk protein solutions for development work and has the potential for transfer to manufacturing.