Protein Sub-Visible Particle and Free Radical formation of a Freeze-Dried Monoclonal Antibody Formulation During Dropping.

Dropping during shipping and handling of liquid biopharmaceutical formulations has long been known to cause protein degradation and aggregation. On the other hand, accidental dropping of freeze-dried protein formulations is generally considered not a major issue for biopharmaceutical quality. Reports of stability and especially the underling degradation mechanism(s) during shipping and handling of freeze-dried protein formulations were rarely seen in literature.

Uncommon Peptide Bond Cleavage of Glucagon from a Specific Vendor under near Neutral to Basic Conditions.

Purpose: The main purposes of this manuscript are to report a surprising and interesting degradation reaction of glucagon from a specific vendor in which glucagon underwent cleavage among several peptide bonds quickly under near neutral to basic conditions, and to propose the root cause of mechanism for the degradation reaction.

Methods: The degradation reaction was monitored by HPLC and the fragment structures were confirmed by LC-MS. Possible impurities responsible for the degradation were either confirmed or excluded by a variety of techniques such as addition of chelator EDTA and transitional metal ions or separation by ultrafiltration.

Formation of protein sub-visible particles during vacuum degassing of etanercept solutions.

The main purpose of this manuscript is to describe a phenomenon in which vacuum degassing a reconstituted freeze-dried fusion protein etanercept formulation caused a significant amount of protein sub-visible particles (SbVP). Physical stability of etanercept was monitored by micro-flow imaging (MFI), dynamic light scattering (DLS), size-exclusion high pressure liquid chromatography (SE-HPLC) and far- and near-ultraviolet circular dichroism (far- and near-UV CD). One potential explanation of this phenomenon is that bubble collapses when the vacuum is applied, leads to substantial heat formation, and ultimately free radical formation.

Regulation of angiotensin-(1-7) and angiotensin II type 1 receptor by telmisartan and losartan in adriamycin-induced rat heart failure.

Aim: To investigate the possible effects of telmisartan and losartan on cardiac function in adriamycin (ADR)-induced heart failure in rats, and to explore the changes in plasma level of angiotensin-(1-7)[Ang-(1-7)] and myocardial expression of angiotensin II type 1/2 receptors (AT(1)R / AT(2)R) and Mas receptor caused by the two drugs.

Methods: Male Sprague-Dawley rats were randomly divided into 4 groups: the control group, ADR-treated heart failure group (ADR-HF), telmisartan plus ADR-treated group (Tel+ADR) and losartan plus ADR-treated group (Los+ADR). ADR was administrated (2.