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Featured researches published by Dennis J. O’Kane.


The Journal of Urology | 2000

A COMPARISON OF CYTOLOGY AND FLUORESCENCE IN SITU HYBRIDIZATION FOR THE DETECTION OF UROTHELIAL CARCINOMA

Kevin C. Halling; Walter King; Irina A. Sokolova; Reid G. Meyer; Haleh M. Burkhardt; Amy C. Halling; John C. Cheville; Thomas J. Sebo; Sanjay Ramakumar; Christopher S. Stewart; Shane Pankratz; Dennis J. O’Kane; Steven A. Seelig; Michael M. Lieber; Robert B. Jenkins

PURPOSE We determine the relative sensitivities of cytology and fluorescence in situ hybridization (FISH) for the detection of urothelial carcinoma. MATERIALS AND METHODS A mixture of fluorescent labeled probes to the centromeres of chromosomes 3, 7 and 17, and band 9p21 (P16/CDKN2A gene) was used to assess urinary cells for chromosomal abnormalities indicative of malignancy. A total of 280 urine specimens from 265 patients, including 150 with a history of urothelial carcinoma and 115 without a history of urothelial carcinoma, were analyzed. FISH analysis was performed without prior knowledge of clinical findings, that is biopsy, cystoscopy and cytology results. A positive result was defined as 5 or more urinary cells with gains of 2 or more chromosomes. RESULTS A total of 75 biopsies showed urothelial carcinoma at FISH analysis among the 265 patients. The sensitivity of urine cytology for pTa (36 cases), pTis (18) and pT1-pT4 (15) tumors was 47%, 78% and 60%, respectively, for an overall sensitivity of 58%. The sensitivity of FISH for pTa (37 cases), pTis (17) and pT1-pT4 (19) tumors was 65%, 100% and 95%, respectively, for an overall sensitivity of 81%. FISH was significantly more sensitive than cytology for pTis (p = 0.046), pT1-pT4 (p = 0.025), grade 3 (p = 0.003) and all tumors (p = 0.001). The specificity of cytology and FISH among patients without cystoscopic evidence of urothelial carcinoma and no history of urothelial carcinoma was 98% and 96%, respectively (p = 0.564). CONCLUSIONS The sensitivity of FISH for the detection of urothelial carcinoma is superior to that of cytology, and the specificity of FISH and cytology for urothelial carcinoma are not significantly different. Further prospective studies are required but FISH has the potential to improve significantly the management of urothelial carcinoma.


The Journal of Urology | 2002

A Comparison of BTA Stat, Hemoglobin Dipstick, Telomerase and Vysis Urovysion Assays for the Detection of Urothelial Carcinoma in Urine

Kevin C. Halling; Walter King; Irina A. Sokolova; R. Jeffrey Karnes; Reid G. Meyer; Eric L. Powell; Thomas J. Sebo; John C. Cheville; Amy C. Clayton; Kelly L. Krajnik; Thomas Ebert; Robert E. Nelson; Haleh M. Burkhardt; Sanjay Ramakumar; Christopher S. Stewart; Vernon S. Pankratz; Michael M. Lieber; Michael L. Blute; Horst Zincke; Steven A. Seelig; Robert B. Jenkins; Dennis J. O’Kane

PURPOSE We determine the sensitivity and specificity of various assays for the detection of urothelial carcinoma. MATERIALS AND METHODS A total of 280 voided urine specimens from 265 patients were obtained immediately before cystoscopy for BTA stat, (Bard Diagnostic, Redmond, Washington) hemoglobin dipstick, (Bayer, Elkhart, Indiana) telomerase and UroVysion (Vysis, a wholly owned subsidiary of Abbott Laboratories, Abbott Park, Illinois) analysis. RESULTS Of the 265 patients 75 had biopsy proven urothelial carcinoma, and the sensitivity of the assays was determined from these patients. From most sensitive to least sensitive, the overall sensitivity of UroVysion (73 cases), BTA stat (72), hemoglobin dipstick (73) and telomerase (70) was 81%, 78%, 74%, and 46%, respectively. Each of the first 3 tests was statistically significantly more sensitive than the telomerase assay (p <0.05). However, the differences in overall sensitivity of UroVysion, BTA stat and hemoglobin dipstick were not statistically significant. The specificity of the tests was calculated for 80 of the 265 patients in this study who had no history of urothelial carcinoma and negative cystoscopy findings despite common urological complaints. From most specific to least specific, the specificity of UroVysion, telomerase, BTA stat and hemoglobin dipstick was 96%, 91%, 74% and 51%, respectively. UroVysion and telomerase were statistically significantly (p <0.01) more specific than the BTA stat and hemoglobin dipstick assays, and all of the assays were more specific than hemoglobin dipstick testing (p <0.001). CONCLUSIONS Our study reveals that UroVysion is the most sensitive and specific assay among those tested for the detection of urothelial carcinoma. Telomerase testing had good specificity but poor sensitivity. The BTA stat and hemoglobin dipstick tests had good sensitivity but relatively poor specificity. UroVysion is a promising new assay for the detection of urothelial carcinoma in urine specimens. However, further studies are needed to explore the role of the various assays in the treatment of patients with superficial urothelial carcinoma.


Expert Opinion on Drug Metabolism & Toxicology | 2007

The impact of CYP allelic variation on antidepressant metabolism: a review

John L. Black; Dennis J. O’Kane; David A. Mrazek

Psychiatric diseases that are treated with antidepressants are the leading causes of morbidity and mortality in humankind. Although antidepressants are generally well tolerated and widely available, they are not equally effective in all patients and only 35 – 45% of patients treated for depression with these drugs recover to premorbid levels of functioning. There is a need for an effective, individualized approach to antidepressant selection. One promising lead in the development of personalized medicine is the emerging field of pharmacogenomics, whereby pharmacologic agents are selected on the basis of the genotype of patients, with particular attention to drug targets and phase I- and phase II-metabolizing enzymes. This review article focusses on phase I antidepressant-metabolizing enzymes (e.g., relevant CYP enzymes). The authors first briefly review CYP nomenclature, the relevant members of the CYP superfamily and their alleles, the metabolic categories and CYP antidepressant substrates, inhibitors and inducers. The literature on the impact of CYP polymorphisms on antidepressant metabolism are also reviewed.


Archive | 1998

The Renilla Luciferase-Modified GFP Fusion Protein is Functional in Transformed Cells

Yubao Wang; Gefu Wang; Dennis J. O’Kane; Aladar A. Szalay

The cDNA of Renilla reniformis luciferase (ruc) has been cloned and used successfully as a marker gene in a variety of transgenic species. Similarly, the transfer and expression of green fluorescent protein (GFP) cDNA (gfp) and its mutants from Aequorea victoria resulted in high levels of GFP in transformed cells, allowing convenient visualization of gene expression under the microscope.


Leukemia Research | 2012

Correlation of CYP2B6, CYP2C19, ABCC4 and SOD2 genotype with outcomes in allogeneic blood and marrow transplant patients

John L. Black; Mark R. Litzow; William J. Hogan; Dennis J. O’Kane; Denise L. Walker; Timothy G. Lesnick; Walter K. Kremers; Rajeswari Avula; Rhett P. Ketterling

CYP2B6, CYP2C19, ABCC4, and SOD2 have been implicated in adverse drug reactions and survival after cyclophosphamide (CPA) treatment. 110 BMT patients who received high dose CPA treatment were genotyped for variants in these genes and the results were correlated with toxicity and relapse. CYP2B6 genotype significantly influenced overall toxicity suggesting active CYP2B6 alleles led to higher rates of overall toxicity. The p.R487C deficiency allele was significantly associated with a lower rate of overall toxicity and a higher rate of relapse. SOD2 rs4880 V16A polymorphism was associated with significantly less CPA-related overall toxicity and significantly lower relapse rates by Kaplan-Meier analysis although the SOD2 finding regarding relapse was not significant when evaluated by the cumulative incidence function.


Pharmacogenomics | 2012

CYP2D6*11 and challenges in clinical genotyping of the highly polymorphic CYP2D6 gene

Jennifer M. Skierka; Denise L. Walker; Sandra Peterson; Dennis J. O’Kane; John L. Black

CYP2D6 is genotyped clinically for prediction of response to tamoxifen, psychotropic drugs and other medications. Phenotype prediction is dependent upon accurate genotyping. The CYP Allele Nomenclature Committee maintains the allelic nomenclature for CYP2D6; however, in some cases, the list of polymorphisms associated with a given allele is incomplete. Clinical laboratories and in vitro diagnostic manufacturers rely upon this nomenclature, in addition to the literature, to infer allelic function and haplotypes and when they design CYP2D6-testing platforms. This article provides more complete sequencing data for the CYP2D6*11 allele and describes the difficulties encountered in genotyping CYP2D6 when incomplete data are available. The CYP Allele Nomenclature Committee should provide clear information about the completeness of the original data used to define each allele.


Molecular Diagnostics#R##N#Techniques and Applications for the Clinical Laboratory | 2010

UDP-Glucuronosyltransferase 1A1 and the Glucuronidation in Oncology Applications and Hyperbilirubinemia

Jennifer M. Skierka; Dennis J. O’Kane

Publisher Summary Glucuronidation is an important phase II reaction catalyzed by the UDP-glucuronosyltransferases (UGTs), UGTs are enzymes involved in a number of metabolic processes, including phase II drug metabolism conjugation of endogenous compounds with glucuronic acid, such as bilirubin and estradiol with glucuronic acid, to form water-soluble conjugates for excretion; and detoxification of potential carcinogens. Clinicians need to be aware of the options available to them for irinotecan and hyperbilirubinemia genetic testing. When complying with the minimum FDA requirements for irinotecan dose adjustments by only testing to determine if the *28 allele is present, patients of African or Asian ancestry could potentially be put at increased risk for neutropenia with this drug. Many factors go into determining hyperbilirubinemia; having a comprehensive genetic test available to aid a physician in treatment options (UGT1A1 genetic based or not) provides the patient with the best clinical outcome. The UGT1A1 gene is a complex gene, not only in its design, with alternative splicing on the 5’ and 3’ end of the gene, but also because of the impact it has on genetic diseases and drug metabolism. In addition, the variations that have been reported (known star alleles) all have different frequencies depending on ethnicity. As a result, an allele (for example, *6) may have vast clinical significance in one ethnicity but is rarely observed in other populations. Only by continuing to investigate and research the gene in various populations can we further our understanding on the clinical significance and impact of UGT1A1.


Clinical Chemistry | 2004

Liquid Chromatography–Tandem Mass Spectrometry Assay for Simultaneous Measurement of Estradiol and Estrone in Human Plasma

Robert E. Nelson; Stefan K. Grebe; Dennis J. O’Kane; Ravinder J. Singh


Clinical Chemistry | 2004

Measurement of Plasma Free Metanephrine and Normetanephrine by Liquid Chromatography–Tandem Mass Spectrometry for Diagnosis of Pheochromocytoma

Susan A. Lagerstedt; Dennis J. O’Kane; Ravinder J. Singh


Clinical Chemistry | 2004

Prevalence of Heterophilic Antibody Interference in Eight Automated Tumor Marker Immunoassays

Carol M. Preissner; Larry A. Dodge; Dennis J. O’Kane; Ravinder J. Singh; Stefan K. Grebe

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