Publications by authors named "Pamela M Ward"

4 Publications

  • Page 1 of 1

Application of Nuclear Magnetic Resonance to Detect Toxigenic Clostridium difficile from Stool Specimens: A Proof of Concept.

J Mol Diagn 2017 03 9;19(2):230-235. Epub 2017 Jan 9.

Keck School of Medicine, University of Southern California, Los Angeles, California. Electronic address:

We evaluated the performance of an early prototype core molecular mirroring nuclear magnetic resonance detection platform (Mentor-100) to detect toxigenic Clostridium difficile from stool. This technology uses customized nanoparticles bound to target specific oligonucleotide probes that form binaries in the presence of nucleic acid from the target microorganism. Liquid patient stool specimens were seeded with C. difficile or other Clostridium species to determine the analytical sensitivity and specificity. Samples underwent nucleic acid extraction and target amplification with probes conjugated with iron nanoparticles. Signal from nuclear magnetic resonance spin-spin relaxation time was measured to detect the presence or absence of toxigenic C. difficile. The limit of detection was <180 colony forming units per reaction of toxigenic C. difficile. No cross-reactivity was observed with nontoxigenic C. difficile, Clostridium sordellii, Clostridium perfringens, Bacillus subtilis, or Paenibacillus polymyxa at 10 colony forming units/mL. Correlation studies using frozen stool samples yielded a sensitivity of 88.4% (61 of 69) and a specificity of 87.0% (40 of 46) as compared with a commercial PCR assay for C. difficile. The area under the curve in the receiver operating characteristic curve analysis was 0.922. The prototype molecular mirroring platform showed promising performance for pathogen detection from clinical specimens. The platform design has the potential to offer a novel, low-cost alternative to currently available nucleic acid-based tests.
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http://dx.doi.org/10.1016/j.jmoldx.2016.09.012DOI Listing
March 2017

Gain of TP53 Mutation in Imatinib-treated SDH-Deficient Gastrointestinal Stromal Tumor and Clinical Utilization of Targeted Next-generation Sequencing Panel for Therapeutic Decision Support.

Appl Immunohistochem Mol Morphol 2018 09;26(8):573-578

Department of Pathology, University of Southern California, Keck School of Medicine.

Patients with succinate dehydrogenase (SDH)-deficient gastrointestinal stromal tumor (GIST) have few therapeutic options. Despite lack of KIT or platelet-derived growth factor receptor A (PDGFRA) driver mutations, SDH-deficient GISTs display strong expression of KIT by immunohistochemistry and these patients are often treated with tyrosine kinase inhibitors, including imatinib as a first-line therapy. Using a targeted next-generation sequencing panel of mutation hotspots of 50-clinically relevant genes, we investigated (1) concurrence of somatic/actionable mutations and (2) tumor molecular evolution by comparing 2 resection specimens 1.5 years apart while the patient was on imatinib adjuvant therapy. We found the tumors did not harbor KIT, PDGFRA, or any other clinically actionable mutations. However, a TP53 mutation (c.422G>A; p.C141Y) was detected in the second recurrent lesion. This represents the first study to monitor the molecular evolution of a SDH-deficient GIST during adjuvant treatment. These findings emphasize the critical need for next-generation sequencing testing before initiating targeted therapy.
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http://dx.doi.org/10.1097/PAI.0000000000000482DOI Listing
September 2018

Extra copies of chromosome 2 are a recurring aberration in ALK-negative lymphomas with anaplastic morphology.

Mod Pathol 2005 Feb;18(2):235-43

Department of Pathology, Buffalo General Hospital, The State University of New York, Buffalo, NY, USA.

The purpose of this study was to evaluate fluorescence in situ hybridization abnormalities of the 2p23 anaplastic lymphoma kinase (ALK) gene loci in lymphomas with anaplastic morphology. We studied 24 anaplastic large cell lymphomas (ALCL) classified by World Health Organization criteria [17 primary nodal/systemic (10 ALK+, 7 ALK-), seven primary cutaneous], and 17 additional non-Hodgkin's lymphomas [one ALK+ B-lineage lymphoma, 14 ALK- diffuse large B-cell lymphomas (seven anaplastic variants, five nonanaplastic, two secondary CD30+), two follicular lymphomas]. ALK- lymphomas with anaplastic morphology showed extra nonrearranged anaplastic lymphoma kinase gene loci (P=0.004) due to trisomy 2 irrespective of the following factors: B or T/null phenotype (P=0.315), diagnostic categories of systemic or cutaneous ALCL or the above-mentioned B-cell lymphomas (P=0.131), and CD30 positivity by immunohistochemistry (P=1.000). Trisomy 2 was absent in all ALK+ lymphomas (P=0.009), which showed rearranged ALK gene loci (P<0.001). Whether trisomy 2 is a primary or secondary event that leads to ALK- lymphomas cannot be determined from this study. Its presence in secondary B-cell lymphomas suggests that trisomy 2 may be a secondary cytogenetic aberration in lymphomas in general. Further investigation of this finding is necessary to further our understanding of the heterogeneous group of ALK- lymphomas.
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http://dx.doi.org/10.1038/modpathol.3800299DOI Listing
February 2005

The creation, implementation, and evaluation of a nurse residency program through a shared leadership model in the intensive care setting.

Dimens Crit Care Nurs 2002 Jul-Aug;21(4):154-61

University of Louisville Hospital, Ky 40205, USA.

This education strategy was used at a 404-bed level-one trauma center where 60% of the beds are for critical care. In June 1999, 93 nurses underwent critical care orientation. By June 2000, only 8 of these nurses remained. Exit interviews revealed the primary reason for leaving was dissatisfaction with orientation. The Education Department undertook a shared leadership approach to identify strategies for resolution of the perceived orientation problem. The Preceptor Leadership Council was formed to create a Nurse Residency Program for new nurses. Membership consisted of staff nurse lead preceptors and clinical educators. Outcomes following the implementation of the program indicated an overall increase in satisfaction with nursing orientation in the intensive care unit as well as a significant reduction in turnover rates. Strategies used to create, implement, and evaluate the program are presented.
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http://dx.doi.org/10.1097/00003465-200207000-00010DOI Listing
September 2002