Publications by authors named "Beth A Young"

Drug product performance is polymorph specific, and it is imperative that solid phase stability be monitored throughout the manufacturing process to ensure final product quality and performance. PXRD remains the gold standard for polymorph identification, but due to a growing interest in continuous manufacturing, a need has emerged for alternative process analytical technologies (PATs) that can provide fast, reliable, and non-destructive polymorph discrimination amenable to in situ process monitoring. Herein we demonstrate an original application of powder Brillouin light scattering (p-BLS) for the discrimination of polymorphic molecular solids.

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Purpose: The unconventional tabletability of the indomethacin polymorphs - α and γ - are investigated from a topological and mechanical perspective using powder Brillouin light scattering (p-BLS) to identify the specific structure-performance relationship in these materials.

Method: Indomethacin (γ-form) was purchased and used to prepare the α polymorph. Powder X-ray diffraction was used to confirm phase identity, while p-BLS was used to obtain the mechanical properties.

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The highly variable pharmacokinetics of β-lactam antibiotics and β-lactamase inhibitors poses a significant challenge to clinicians in ensuring appropriate antibiotic doses in critically ill patients. Therefore, routine monitoring of plasma concentrations is important for individualization of antimicrobial therapy. Accordingly, a simple and robust analytical method for the simultaneous measurement of multiple β-lactam antibiotics and β-lactamase inhibitors is highly desirable to ensure quick decisions on dose adjustments.

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Although the stability of β-lactam antibiotics is a known issue, none of the previously reported bioanalytical methods had an adequate evaluation of the stability of these drugs. In the current study, the stability of cefepime, meropenem, piperacillin, and tazobactam under various conditions was comprehensively evaluated. The evaluated parameters included stock solution stability, short-term stability, long-term stability, freeze-thaw stability, processed sample stability, and whole-blood stability.

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The major pelvic ganglia (MPG) contain both parasympathetic and sympathetic postganglionic neurons and provide much of the autonomic innervation to urogenital organs and components of the lower bowel. Whereas many parasympathetic neurons were found to express vasoactive intestinal polypeptide (VIP), no MPG neurons exhibited immunoreactivity for pituitary adenylate cyclase-activating polypeptide (PACAP). However, in 3-day cultured MPGs, numerous PACAP-IR cells and nerve fibers were present, and transcript levels for PACAP increased significantly.

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Cultured guinea pig atrial whole mounts containing the intrinsic cardiac ganglia were used as an in vitro model to investigate the induction of the stress/injury marker activating transcription factor 3 (ATF-3). ATF-3 expression was quantified by using immunocytochemical labeling and real-time PCR. In freshly isolated ganglia, no neuronal or Schwann cell nuclei exhibited ATF-3 immunoreactivity.

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Pituitary adenylate cyclase-activating polypeptide (PACAP) effects on intracellular calcium ([Ca2+]i) and excitability have been studied in adult guinea pig intracardiac neurons. PACAP increased excitability, but did not elicit Ca2+ release from intracellular stores. Exposure to a Ca2+-deficient solution did not deplete [Ca2+]i stores but did eliminate the PACAP-induced increase in excitability.

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Pituitary adenylate cyclase-activating polypeptide (PACAP) expression was quantified in explant-cultured guinea pig cardiac ganglia neurons. In explant culture, both the percentage of PACAP-immunoreactive neurons and pro-PACAP transcript levels increased significantly. Treatment with neurturin or glial-derived neurotrophic factor significantly suppressed the percentage of PACAP-IR neurons, but not pro-PACAP transcript levels.

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The presence of vasoactive intestinal polypeptide (VIP) has been analyzed in fibers and neurons within the guinea pig intrinsic cardiac ganglia and in fibers innervating cardiac tissues. In whole-mount preparations, VIP-immunoreactive (IR) fibers were present in about 70% of the cardiac ganglia. VIP was co-localized with neuronal nitric oxide synthase (nNOS) in fibers innervating the intrinsic ganglia but was not present in fibers immunoreactive for pituitary adenylate cyclase-activating polypeptide, choline acetyltransferase (ChAT), tyrosine hydroxylase, or substance P.

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Cheerleading, traditionally considered a nonathletic activity, has evolved into a competitive sport requiring high levels of fitness. Despite the trend of cheerleaders performing increasingly difficult and athletic skills, very little is known about their fitness levels. The purpose of this study was to provide a physiological profile of the fitness status of a squad of collegiate cheerleaders.

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