Publications by authors named "Rebecca Booth"

The synthesis of drug-loaded PLGA nanoparticles through nanoprecipitation in solvent/antisolvent mixtures is well reported but lacks clarity in explaining drug loading mechanisms and the prediction of efficiency of drug entrapment. Various methods using physical parameters such as log and solid-state drug-polymer solubility aim to predict the intensity of drug-polymer interactions but lack precision. In particular, the zero-enthalpy method for drug/polymer solubility may be intrinsically inaccurate, as we demonstrate.

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Hydrophobic ion pairing (HIP) can successfully increase the drug loading and control the release kinetics of ionizable hydrophilic drugs, addressing challenges that prevent these molecules from reaching the clinic. Nevertheless, polymeric nanoparticle (PNP) formulation development requires trial-and-error experimentation to meet the target product profile, which is laborious and costly. Herein, we design a preformulation framework (solid-state screening, computational approach, and solubility in PNP-forming emulsion) to understand counterion-drug-polymer interactions and accelerate the PNP formulation development for HIP systems.

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Background: Current research into virtual reality (VR) use during chemotherapy shows that it can be an effective distraction intervention. However, there is limited research in adult patients and to investigate how VR can be sustainably implemented in health care organizations.

Objective: The aim of this study was to explore the feasibility and acceptability of using VR for adult patients undergoing chemotherapy, and to identify the factors that would enable the sustained use of VR during chemotherapy in health care organizations.

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Non-invasive stress and nutritional hormone analysis in relation to ecological and other biological indices have tremendous potential to address environmental disturbance impacts on wildlife health. To this end, we examined the relation between glucocorticoid (GC) and thyroid (T3) hormone indices of disturbance and nutritional stress in response to ACTH and TSH challenges in captive tigers, as well as how reproductive hormones vary by sex and reproductive condition. Glucocorticoid, thyroid, progesterone and androgen assays conducted on high-performance liquid chromatography separated fractions of biologically relevant fecal extracts revealed high cross-reactivity of these assays for their respective biologically relevant fecal hormone metabolites.

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Linking changes in amino acid sequences to the evolution of transcription regulatory domains is often complicated by the low sequence complexity and high mutation rates of intrinsically disordered protein regions. For the Hox transcription factor Ultrabithorax (Ubx), conserved motifs distributed throughout the protein sequence enable direct comparison of specific protein regions, despite variations in the length and composition of the intervening sequences. In cell culture, the strength of transcription activation by Drosophila melanogaster Ubx correlates with the presence of a predicted helix within its activation domain.

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The Southern Resident killer whale population (Orcinus orca) was listed as endangered in 2005 and shows little sign of recovery. Exposure to contaminants and risk of an oil spill are identified threats. Previous studies on contaminants have largely focused on legacy pollutants.

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Article Synopsis
  • The development of protein-based functionalized materials is crucial for various applications due to their biocompatibility, biodegradability, and diverse mechanical properties.
  • Gene fusion techniques allow the incorporation of active proteins into these materials, but traditional methods often require harsh conditions that can deactivate these proteins.
  • This chapter presents a mild, cost-effective approach to create protein fibers and films in neutral pH environments, along with techniques to form fiber bundles and utilize them in cell culture, with potential applications beyond the specific protein studied.
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Several hormones are potential indicators of stress in free-ranging animals and provide information on animal health in managed-care settings. In response to stress, glucocorticoids (GC, e.g.

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OBJECTIVE To evaluate the impact of oral megestrol acetate (MA) administration on adrenal function in male bottlenose dolphins (Tursiops truncatus). DESIGN Serial cross-sectional study. ANIMALS 8 adult male dolphins, all of which were receiving MA at various daily doses (range, 0 to 60 mg, PO) for the control of reproductive behavior.

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Article Synopsis
  • - The Southern Resident killer whale population has been endangered since 2005, struggling with low reproductive success, primarily due to a shortage of their main prey, the endangered Chinook salmon, alongside other stressors like toxins and vessel disturbances.
  • - Research utilized hormone analysis from killer whale feces to evaluate pregnancy rates and health, indicating that up to 69% of detectable pregnancies were unsuccessful, with significant failures occurring late in gestation or after birth due to both nutritional stress and toxic exposure.
  • - The findings suggest that recovering Chinook salmon populations is crucial for the growth of Southern Resident killer whales, and the hormone measurement techniques developed can help monitor the effectiveness of future conservation efforts.
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Persistent organic pollutants (POPs), specifically PCBs, PBDEs, and DDTs, in the marine environment are well documented, however accumulation and mobilization patterns at the top of the food-web are poorly understood. This study broadens the understanding of POPs in the endangered Southern Resident killer whale population by addressing modulation by prey availability and reproductive status, along with endocrine disrupting effects. A total of 140 killer whale scat samples collected from 54 unique whales across a 4 year sampling period (2010-2013) were analyzed for concentrations of POPs.

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Knowledge regarding stress hormones and how they vary in response to seasonality, gender, age, and reproductive status for any marine mammal is limited. Furthermore, stress hormones may be measured in more than one matrix (e.g.

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The winter diet of barren-ground caribou may affect adult survival, timing of parturition, neonatal survival, and postpartum mass. We used microhistological analyses and hormone levels in feces to determine sex-specific late-winter diets, pregnancy rates, group composition, and endocrine-based measures of physiological and nutritional stress. Lichens, which are highly digestible but contain little protein, dominated the diet (> 68%) but were less prevalent in the diets of pregnant females as compared to non-pregnant females and males.

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Objective: To determine the effect of natural exposure to domoic acid (DA) on eosinophil counts and adrenal gland function in California sea lions (Zalophus californianus).

Design: Cross-sectional prospective study.

Animals: 39 California sea lions.

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State and federal actions to conserve northern spotted owl (Strix occidentalis caurina) habitat are largely initiated by establishing habitat occupancy. Northern spotted owl occupancy is typically assessed by eliciting their response to simulated conspecific vocalizations. However, proximity of barred owls (Strix varia)-a significant threat to northern spotted owls-can suppress northern spotted owl responsiveness to vocalization surveys and hence their probability of detection.

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Managing endangered species often involves evaluating the relative impacts of multiple anthropogenic and ecological pressures. This challenge is particularly formidable for cetaceans, which spend the majority of their time underwater. Noninvasive physiological approaches can be especially informative in this regard.

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Multidrug-resistant organisms (MDROs) are increasingly implicated in both acute and chronic wound infections. The limited therapeutic options are further compromised by the fact that wound bacteria often co-exist within a biofilm community which enhances bacterial tolerance to antibiotics. As a consequence, topical antiseptics may be an important consideration for minimising the opportunity for wound infections involving MDROs.

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A series of 1-alkyl-4-aryl-1,2,3-triazoles (1-methyl-4-phenyl-1,2,3-triazole (1a); 1-propyl-4-phenyl-1,2,3-triazole (1b); 1-benzyl-4-phenyl-1,2,3-triazole (1c); 1-propyl-4-p-tolyl-1,2,3-triazole (1d)) have been prepared through a one-pot procedure involving in situ generation of the alkyl azide from a halide precursor followed by copper catalysed alkyne/azide cycloaddition (CuAAC) with the appropriate aryl alkyne. Cationic Re(I) complexes [Re(bpy)(CO)(3)(1a-d)]PF(6) (2a-d) were then prepared by stirring [Re(bpy)(CO)(3)Cl] with AgPF(6) in dichloromethane in the presence of ligands 1a-d. X-ray crystal structures were obtained for 2a and 2b.

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Avian endocrinology is a productive field that could benefit from increased application of non-invasive techniques. Although assay protocols vary, most studies that measure hormone metabolites in avian feces struggle with an artificial effect of sample mass on steroid metabolite concentration. Hormone metabolite concentrations measured in small samples are consistently higher than concentrations in larger samples, and this appears to be due to multiple methodological problems.

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We developed and validated a non-invasive thyroid hormone measure in feces of a diverse array of birds and mammals. An I(131) radiolabel ingestion study in domestic dogs coupled with High Pressure Liquid Chromatography (HPLC) analysis, showed that peak excretion in feces occurred at 24-48h post-ingestion, with I(131)-labelled thyroid hormone metabolites excreted primarily as triiodothyronine (T3) and relatively little thyroxine (T4), at all excretion times examined. The immunoreactive T3 profile across these same HPLC fractions closely corresponded with the I(131) radioactive profile.

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The illegal ivory trade recently intensified to the highest levels ever reported. Policing this trafficking has been hampered by the inability to reliably determine geographic origin of contraband ivory. Ivory can be smuggled across multiple international borders and along numerous trade routes, making poaching hotspots and potential trade routes difficult to identify.

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