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Tampa, FL, United States

Boucher K.,H. Lee Moffitt Cancer Center and Research Institute | Parquet N.,H. Lee Moffitt Cancer Center and Research Institute | Widen R.,Esoteric Testing Laboratory | Shain K.,H. Lee Moffitt Cancer Center and Research Institute | And 6 more authors.
Clinical Cancer Research | Year: 2012

Purpose: In myeloma, B cells and plasma cells show a clonal relationship. Clonotypic B cells may represent a tumor-initiating compartment or cancer stem cell responsible for minimal residual disease in myeloma. Experimental Design: We report a study of 58 patients with myeloma at time of diagnosis or relapse. B cells in bone marrow were evaluated by multicolor flow cytometry and sorting. Clonality was determined by light chain and/or immunoglobulin chain gene rearrangement PCR. We also determined aldehyde dehydrogenase activity and colony formation growth. Drug sensitivity was tested with conventional and novel agents. Results: Marrow CD19+ cells express a light chain identical to plasma cells and are therefore termed light chain restricted (LCR). The LCR B-cell mass is small in both newly diagnosed and relapsed patients (≤1%). Few marrow LCR B cells (∼10%) are CD19+/CD34+, with the rest being more differentiated CD19+/CD34- B cells. Marrow LCR CD19+ B cells exhibit enhanced aldehyde dehydrogenase activity versus healthy controls. Both CD19+/CD34+ and CD19+/CD34- cells showed colony formation activity, with colony growth efficiency optimized when stroma-conditioned medium was used. B-cell progenitors showed resistance to melphalan, lenalidomide, and bortezomib. Panobinostat, a histone deacetylase inhibitor, induced apoptosis of LCR B cells and CD138+ cells. LCR B cells are CD117, survivin, and Notch positive. Conclusions: We propose that antigen-independent B-cell differentiation stages are involved in disease origination and progression in myeloma. Furthermore, investigations of myeloma putative stem cell progenitors may lead to novel treatments to eradicate the potential reservoir of minimal residual disease. ©2012 AACR. Source

Rolfe N.E.,University of South Florida | Garcia C.,University of South Florida | Widen R.H.,Esoteric Testing Laboratory | Taylor S.P.,University of South Florida
Journal of Medical Microbiology | Year: 2013

Nontuberculous mycobacteria are widely distributed in the environment and have the potential to cause a wide spectrum of infections including pulmonary, bone, soft tissue or ocular infections. They are a rare cause of endophthalmitis, a potentially devastating condition, which may be acquired through contamination of water or antiseptic solutions. Diagnosis is often delayed due to low clinical suspicion, resulting in poor clinical outcomes. Newer laboratory techniques such as real-time PCR can be used for rapid detection, identification and speciation of mycobacteria and allow for initiation of focused antibiotic therapy. We describe a case of Mycobacterium abscessus endophthalmitis that developed 30 years after traumatic loss of cornea in a patient with diabetes mellitus. © 2013 SGM. Source

Silva F.M.,University of Sao Paulo | Carmo M.S.,University of Sao Paulo | Carmo M.S.,Centro Universitario | Silbert S.,Esoteric Testing Laboratory | Gales A.C.,University of Sao Paulo
Microbial Drug Resistance | Year: 2011

In Brazil, the spread of an endemic clone of SPM-1-producing Pseudomonas aeruginosa has been reported. Recently, a higher genomic variety has been observed among the SPM-1-producing P. aeruginosa isolates. The principal aim of this study was to analyze through multilocus sequence typing (MLST) analysis whether the recently isolated SPM-1-producing P. aeruginosa descend or not from a common ancestor. A total of 50 SPM-1-producing P. aeruginosa exhibiting 11 distinct ribotyping genotypes collected from 11 different Brazilian cities were studied. Three IMP-1-producing P. aeruginosa and two non-metallo-beta-lactamase- producing P. aeruginosa isolates were included in the study as controls. For assignment of allelic numbers and subsequent determination of sequence type (ST), the obtained sequences were compared to existing sequences in the MLST database (www.pubmlst.org/paeruginosa). The eBURSTv3 software was used in this study for establishing the evolutionary relationship and phylogenetic analysis. A total of 5 different STs were identified among 55 P. aeruginosa isolates. All of the SPM-1-producing P. aeruginosa presented an identical allelic profile (ST277), except for one strain. The three IMP-1-producing P. aeruginosa strains were classified as belonging to the ST593, whereas the non-metallo-beta- lactamase-producing P. aeruginosa showed two new distinct STs, ST594 and ST595. Our study shows that SPM-1-producing P. aeruginosa isolates as well as the IMP producers evaluated in this study descend from a common ancestor. © 2011, Mary Ann Liebert, Inc. Source

Widen R.,Esoteric Testing Laboratory | Healer V.,Esoteric Testing Laboratory | Silbert S.,Esoteric Testing Laboratory
Journal of Clinical Microbiology | Year: 2014

A comparison between the BD MAX MRSA and Xpert MRSA assays was performed using 239 nares samples. A 97.9% overall agreement between the two molecular assays was observed. The BD MAX MRSA assay proved to be a reliable alternative for a highly automated system to detect methicillin-resistant Staphylococcus aureus (MRSA) in patient nares samples. Copyright © 2014, American Society for Microbiology. All Rights Reserved. Source

Silbert S.,Esoteric Testing Laboratory | Rocchetti T.T.,Esoteric Testing Laboratory | Rocchetti T.T.,Federal University of Sao Paulo | Gostnell A.,Esoteric Testing Laboratory | And 2 more authors.
Journal of Clinical Microbiology | Year: 2016

Group B Streptococcus detection directly from Copan ESwab collected samples, using the BD Max GBS assay, was evaluated on receipt in the laboratory and after 24 h at room temperature. Results were compared to those using Lim broth enrichment PCR and culture. No significant difference was observed between 24 h ESwab and Lim broth PCRs. © 2016, American Society for Microbiology. All Rights Reserved. Source

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