Now showing items 1-20 of 1342

    • Teeth whitening product exposures reported to United States poison centers, 2001-2020

      Lam, Angela H.; Leonard, James B.; Anderson, Bruce D. (2022-09-16)
    • Effect of Excipients on the Performance of Spray-dried Amorphous Solid Dispersion (ASD) in Tablets

      Yu, Dongyue; Hoag, Stephen W. (2022)
      Amorphous solid dispersions (ASD) are a proven method of improving the solubility and bioavailability of poorly soluble drugs. Immediate-release tablets are frequently used as the final dosage form for ASDs. The selection of polymers and excipients is critical for the manufacturability and bioavailability of ASD tablets. ASDs were prepared by spray drying; ASD tablets were then generated using a compaction simulator. We first studied the impact of polymer types and drug-polymer ratios on bulk powder properties, morphologies, and compaction behaviors of ASDs. Itraconazole (ITZ) and indomethacin (IND) were used as model drugs, and two polymers were used: hydroxypropyl methylcellulose acetate succinate (HPMCAS) and polyvinylpyrrolidone (PVP). The results indicated that the tabletability increased with decreasing drug loadings, except for ITZ-PVP ASDs. Multivariate analysis revealed that particle surface area was the most significant factor influencing the tensile strength of ASD tablets. Secondly, the contact angle and surface free energy of ITZ ASD tablets containing different HPMCAS grades and drug loadings were evaluated using a Drop Shape Analyzer. A larger contact angle was correlated with a higher dissolution rate, suggesting that contact angle could be a high throughput tool for screening ASDs formulations. Lastly, we investigated the influence of fillers such as microcrystalline cellulose, lactose, mannitol, and starch on drug release and stability of ITZ-HPMCAS ASDs. We discovered that the dissolution performance and physical stability of tablets were influenced by the choice of filler. The results and inferences drawn from this research will provide valuable insights into ASD formulation development downstream tablet production.
    • The Regulatory Role of the Cytoplasmic Heme Binding Protein PhuS in Pseudomonas aeruginosa

      Wilson, Tyree; Wilks, Angela (2022)
      Pseudomonas aeruginosa is an opportunistic pathogen that requires iron for its survival and virulence. P. aeruginosa can acquire iron from heme via the nonredundant heme assimilation system and Pseudomonas heme uptake (Phu) systems. Heme transported by either system is eventually sequestered by the cytoplasmic protein PhuS, which specifically shuttles heme to the iron-regulated heme oxygenase HemO. Furthermore, a conformational rearrangement upon heme binding is necessary for the protein-protein interaction with HemO and a ligand switch between the heme coordinating ligands (His209 and His212) was proposed ot be required for translocation of heme to HemO. As the PhuS homolog ShuS from Shigella dysenteriae was observed to bind DNA as a function of its heme status, we sought to further determine if PhuS, in addition to its role in regulating heme flux through HemO, functions as a DNA-binding protein. Herein, through a combination of chromatin immunoprecipation-PCR, EMSA, and fluorescence anisotropy, we show that apo-PhuS but not holo-PhuS binds upstream of the tandem iron- responsive sRNAs prrF1, F2. Previous studies have shown the PrrF sRNAs are required for sparing iron for essential proteins during iron starvation. Furthermore, under certain conditions, a heme-dependent read through of the prrF1 terminator yields the longer PrrH transcript. Quantitative PCR analysis of P. aeruginosa WT and ΔphuS strains shows that loss of PhuS abrogates the heme-dependent regulation of PrrF and PrrH levels. Taken together, our data show that PhuS, in addition to its role in extracellular heme metabolism, can also modulate PrrF and PrrH levels in response to heme. The dual function of PhuS is central to integrating extracellular heme utilization into the PrrF/PrrH sRNA regulatory network that is critical for P. aeruginosa adaptation and virulence within the host. Additional biophysical, genetic and metabolic approaches have been conducted to determine the role of the PhuS heme coordinating residues regulate the mutual exclusivity of heme and DNA binding and the resulting effects on PrrF and PrrH expression.
    • Maryland Pharmacist Winter-Fall 2015

      Maryland Pharmaceutical Association (Baltimore, Maryland (Winter, Spring 2015); Columbia, Maryland (Summer, Fall 2015) : Maryland Pharmaceutical Association, 2015)
    • Maryland Pharmacist Winter-Fall 2021

      Maryland Pharmaceutical Association (Columbia, Maryland : Maryland Pharmaceutical Association, 2021)
    • Maryland Pharmacist Winter-Fall 2018

      Maryland Pharmaceutical Association (Columbia, Maryland : Maryland Pharmaceutical Association, 2018)
    • Maryland Pharmacist Winter-Fall 2019

      Maryland Pharmaceutical Association (Columbia, Maryland : Maryland Pharmaceutical Association, 2019)
    • Maryland Pharmacist Winter-Fall 2017

      Maryland Pharmaceutical Association (Columbia, Maryland : Maryland Pharmaceutical Association, 2017)
    • Maryland Pharmacist Winter-Fall 2016

      Maryland Pharmaceutical Association (Columbia, Maryland : Maryland Pharmaceutical Association, 2016)
    • Maryland Pharmacist Winter-Fall 2020

      Maryland Pharmaceutical Association (Columbia, Maryland : Maryland Pharmaceutical Association, 2020)
    • Maryland Pharmacist Winter-Fall 2014

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 2014)
    • Maryland Pharmacist 72:no. 1-6 (1996); 73:no. 1-4 (1997)

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 1997)
    • Maryland Pharmacist 71:no. 1-12 (1995)

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 1995)
    • Maryland Pharmacist 86: no. 1-4 (2010); 87:no. 1-2 (2011); Fall 2011

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 2011)
    • Maryland Pharmacist 84: no. 1-4 (2008); 85:no. 1-4 (2009)

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 2009)
    • Maryland Pharmacist 78:no. 1-4 (2002); 79:no. 1-3 (2003)

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 2003)
    • Maryland Pharmacist 82:no. 1-3 (2006); 83:no. 1-4 (2007)

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 2007)
    • Maryland Pharmacist 80:no. 1-4 (2004); 81:no. 1-4 (2005)

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 2005)
    • Maryland Pharmacist Spring-Fall 2012; Spring-Winter 2013

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 2013)
    • Maryland Pharmacist 74:no. 1-4 (1998); 75:no. 1-4 (1999)

      Maryland Pharmaceutical Association (Baltimore, Maryland : Maryland Pharmaceutical Association, 1999)