Search

Your search keyword '"Cobice, Diego F."' showing total 5 results
Start Over Author "Cobice, Diego F." Publisher elsevier
5 results on '"Cobice, Diego F."'

1. List of contributors

Author

Adams, John S., primary, Amrein, Karin, additional, Anderson, Paul H., additional, Arnold, Leggy A., additional, Arora, Juhi, additional, Artusa, Patricio, additional, Ascherio, Alberto, additional, Asmussen, Niels C., additional, Astier, Anne L., additional, Bak, Min Ji, additional, Bauerle, Kevin T., additional, Belorusova, Anna Y., additional, Benkusky, Nancy A., additional, Bernal-Mizrachi, Carlos, additional, Bhattoa, Harjit P., additional, Bikle, Daniel D., additional, Bilezikian, John P., additional, Binkley, Neil C., additional, Bischoff-Ferrari, Heike A., additional, Bishop, Charles W., additional, Blomberg Jensen, Martin, additional, Boisen, Ida Marie, additional, Boucher, Barbara J., additional, Bouillon, Roger, additional, Boyan, Barbara D., additional, Bradford, Dana, additional, Brancatella, Alessandro, additional, Buburuzan, Laura, additional, Burne, Thomas H.J., additional, Buschittari, Damien, additional, Calkins, Hannah, additional, Calvo, Mona S., additional, Camargo, Carlos A., additional, Campbell, Moray J., additional, Cantorna, Margherita T., additional, Cappellani, Daniele, additional, Carlberg, Carsten, additional, Carmeliet, Geert, additional, Cashman, Kevin D., additional, Ceglia, Lisa, additional, Cetani, Filomena, additional, Chang, Wenhan, additional, Cheadle, Charlotte, additional, Chou, Sharon H., additional, Christakos, Sylvia, additional, Christopher, Kenneth B., additional, Chu, Emily Y., additional, Chun, Rene F., additional, Cleal, Jane K., additional, Cobice, Diego F., additional, Cooper, Cyrus, additional, Coort, Susan L.M., additional, Cui, Xiaoying, additional, Curtis, Elizabeth M., additional, Danilenko, Michael, additional, Darling, Andrea L., additional, David Roodman, G., additional, Dawson-Hughes, Bess, additional, de Jongh, Renate, additional, Demay, Marie B., additional, Dennison, Elaine M., additional, Dixon, Katie M., additional, Dong, Bingning, additional, Doroudi, Maryam, additional, Dusso, Adriana, additional, Dvorzhinskiy, Aleksey, additional, Ebeling, Peter R., additional, Erben, Reinhold G., additional, Evelo, Chris T.A., additional, Eyles, Darryl, additional, Feldman, David, additional, Ferrer-Mayorga, Gemma, additional, Fleet, James C., additional, Forcellati, Marianela, additional, Foster, Brian L., additional, Gafni, Rachel I., additional, Gayan-Ramirez, Ghislaine, additional, Giovannucci, Edward, additional, Girgis, Christian M., additional, Glencross, Drew A., additional, Glorieux, Francis H., additional, Gocek, Elzbieta, additional, Goldfarb, David S., additional, Goltzman, David, additional, González-Sancho, José Manuel, additional, Grant, William B., additional, Groves, Natalie J., additional, Gysemans, Conny, additional, Harrison, Stephanie, additional, Harvey, Nicholas C., additional, Haseltine, Katherine, additional, Hawrylowicz, Catherine M., additional, Hayes, Colleen E., additional, Heckel, John E., additional, Hershberger, Pamela A., additional, Hewison, Martin, additional, Högler, Wolfgang, additional, Holick, Michael F., additional, Hollis, Bruce W., additional, Holt, Rune, additional, Hujoel, Philippe P., additional, Hyppönen, Elina, additional, Ismailova, Aiten, additional, Jablonski, Nina G., additional, Jakobsen, Jette, additional, Janssens, Wim, additional, Jeffery, Louisa, additional, Jenkinson, Carl, additional, Jensen, Marie Bagge, additional, Jetten, Anton M., additional, Jiang, Heng, additional, Johnson, Candace S., additional, Jones, Glenville, additional, Jones, Kerry S., additional, Jüppner, Harald, additional, Kalia, Vandana, additional, Kallay, Enikö, additional, Karapalis, Andrew C., additional, Kaufmann, Martin, additional, Kiely, Mairead, additional, Kim, Hanseul, additional, Kim, Tiffany Y., additional, Kojima, Hiroyuki, additional, Kooij, Ireen, additional, Kovacs, Christopher S., additional, Kremer, Richard, additional, Krieger, Kirsten, additional, Kritmetapak, Kittrawee, additional, Krueger, Diane C., additional, Kumar, Rajiv, additional, Kurihara, Noriyoshi, additional, Lane, Joseph M., additional, Lanham-New, Susan A., additional, Latic, Nejla, additional, LeBoff, Meryl S., additional, Lee, Maija B., additional, Lee, Seong Min, additional, Levine, Michael A., additional, Lewis, Richard, additional, Lewis, Rohan M., additional, Li, Wei, additional, Li, Yan Chun, additional, Lincoln, Matthew R., additional, Lips, Paul, additional, Lisse, Thomas S., additional, Liu, Eva S., additional, López de Maturana, Evangelina, additional, Lugg, Sebastian T., additional, Machado, Christopher J., additional, Maes, Karen, additional, Maestro, Miguel A., additional, Malats, Núria, additional, Malloy, Peter J., additional, Manousaki, Despoina, additional, Marcinkowska, Ewa, additional, Marcocci, Claudio, additional, Martens, Pieter-Jan, additional, Martineau, Adrian R., additional, Mason, Rebecca S., additional, Mathieu, Chantal, additional, Mayne, Phoebe, additional, McGrath, John J., additional, Mehta, Mansi, additional, Mellanby, Richard John, additional, Merchant, Nadia, additional, Meyer, Mark B., additional, Miao, Dengshun, additional, Moon, Rebecca J., additional, Mortensen, Li Juel, additional, Motlaghzadeh, Yasaman, additional, Munger, Kassandra L., additional, Muñoz, Alberto, additional, Nakamichi, Yuko, additional, Narvaez, Carmen J., additional, Nikiphorou, Elena, additional, Nonn, Larisa, additional, Pal, Lubna, additional, Parekh, Dhruv, additional, Pettifor, John M., additional, Pike, J. Wesley, additional, Pilz, Stefan, additional, Pittas, Anastassios G., additional, Pludowski, Pawel, additional, Prosser, David E., additional, Pullagura, Sri Ramulu N., additional, Raphael, Joseph, additional, Rauz, Saaeha, additional, Raza, Karim, additional, Real, Francisco X., additional, Reichrath, Jörg, additional, Richards, J. Brent, additional, Rivadeneira, Fernando, additional, Rochel, Natacha, additional, Roizen, Jeffrey D., additional, Ryan, Brittany A., additional, Sarkar, Surojit, additional, Sarmadi, Fatemeh, additional, Schafer, Anne L., additional, Schepelmann, Martin, additional, Schoenmakers, Inez, additional, Schuit, Frans, additional, Schwartz, Zvi, additional, Scott, Kayla M., additional, Sellmeyer, Deborah E., additional, Sempos, Christopher T., additional, Sepiashvili, Lusia, additional, Seshadri, Mukund, additional, Shane, Elizabeth, additional, Shaurova, Tatiana, additional, Shieh, Albert, additional, Shui, Irene, additional, Singh, Ravinder J., additional, Slominski, Andrzej T., additional, Smith, Karl W., additional, St-Arnaud, René, additional, Stein, Emily M., additional, Studzinski, George P., additional, Suda, Tatsuo, additional, Takahashi, Naoyuki, additional, Taylor, Hugh S., additional, Tebben, Peter J., additional, Thacher, Tom D., additional, Thandrayen, Kebashni, additional, Thickett, David R., additional, Tiosano, Dov, additional, Trajanoska, Katerina, additional, Tu, Chia-Ling, additional, Tuckey, Robert C., additional, Tutaworn, Teerapat, additional, Udagawa, Nobuyuki, additional, Uday, Suma, additional, Unnanuntana, Aasis, additional, van Driel, Marjolein, additional, van Leeuwen, Johannes P.T.M., additional, van Schoor, Natasja, additional, Verlinden, Lieve, additional, Vieth, Reinhold, additional, Vimaleswaran, Karina S., additional, Wagner, Carol L., additional, Wallace, Graham R., additional, Weaver, Connie M., additional, Webb, Daniel A., additional, Welsh, JoEllen, additional, White, John H., additional, Whiting, Susan J., additional, Williams, Emma L., additional, Yahyavi, Sam Kafai, additional, Yamamoto, Keiko, additional, Yates, Clayton, additional, Zagorac, Sladjana, additional, Zhang, Rong Mei, additional, Zhao, Hengguang, additional, Zhou, Ang, additional, and Zittermann, Armin, additional

Published
2024
Full Text
View/download PDF

2. Derivatization with 2-hydrazino-1-methylpyridine enhances sensitivity of analysis of 5α-dihydrotestosterone in human plasma by liquid chromatography tandem mass spectrometry.

Author

Faqehi AM, Denham SG, Naredo G, Cobice DF, Khan S, Simpson JP, Sabil G, Upreti R, Gibb F, Homer NZ, and Andrew R

Subjects
Adult, Androgens blood, Androstenedione blood, Biological Assay, Calibration, Chromatography, Liquid, Female, Humans, Hydrazines chemical synthesis, Male, Pyridines chemical synthesis, Reference Standards, Reproducibility of Results, Testosterone blood, Dihydrotestosterone blood, Hydrazines chemistry, Pyridines chemistry, Tandem Mass Spectrometry methods
Abstract

Liquid Chromatography tandem mass spectrometry (LC-MS/MS) is the gold-standard approach for androgen analysis in biological fluids, superseding immunoassays in selectivity, particularly at low concentrations. While LC-MS/MS is established for analysis of testosterone and androstenedione, 5α-dihydrotestosterone (DHT) presents greater analytical challenges. DHT circulates at low nanomolar concentrations in men and lower in women, ionizing inefficiently and suffering from isobaric interference from other androgens. Even using current LC-MS/MS technology, large plasma volumes (>0.5 mL) are required for detection, undesirable clinically and unsuitable for animals. This study investigated derivatization approaches using hydrazine-based reagents to enhance ionization efficiency and sensitivity of analysis of DHT by LC-MS/MS. Derivatization of DHT using 2-hydrazino-1-methylpyridine (HMP) and 2-hydrazino-4-(trifluoromethyl)-pyrimidine (HTP) were compared. A method was validated using an UHPLC interfaced by electrospray with a triple quadruple mass spectrometer , analyzing human plasma (male and post-menopausal women) following solid-phase extraction. HMP derivatives were selected for validation affording greater sensitivity than those formed with HTP. HMP derivatives were detected by selected reaction monitoring (DHT-HMP m/z 396→108; testosterone-HMP m/z 394→108; androstenedione-HMP m/z 392→108). Chromatographic separation of androgen derivatives was optimized, carefully separating isobaric interferents and acceptable outputs for precision and trueness achieved following injection of 0.4 pg on column (approximately 34 pmol/L). HMP derivatives of all androgens tested could be detected in low plasma volumes: male (100 µL) and post-menopausal female (200 µL), and derivatives were stable over 30 days at -20°C. In conclusion, HMP derivatization, in conjunction with LC-MS/MS, is suitable for quantitative analysis of DHT, testosterone and androstenedione in low plasma volumes, offering advantages in sensitivity over current methodologies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier B.V.)

Published
2021
Full Text
View/download PDF

3. Effects of vitamin D as a regulator of androgen intracrinology in LNCAP prostate cancer cells.

Author

Smith KW, Thompson PD, Rodriguez EP, Mackay L, and Cobice DF

Subjects
Humans, Ligands, Male, Prostatic Neoplasms metabolism, Prostatic Neoplasms pathology, Tumor Cells, Cultured, Androgen Antagonists pharmacology, Androgens metabolism, Prostatic Neoplasms drug therapy, Vitamin D pharmacology
Abstract

Prostate cancer is initially treated via androgen deprivation therapy (ADT), a highly successful treatment in the initial pursuit of tumor regression, but commonly restricted by the eventual emergence of a more lethal 'castrate resistant' form of the disease. Intracrine pathways that utilize dehydroepiandrosterone (DHEA) or other circulatory precursor steroids, are thought to generate relevant levels of growth-stimulating androgens such as testosterone (T) and dihydrotestosterone (DHT). In this study, we explored the capacity of the active vitamin D hormone to interact and elicit changes upon this prostatic intracrine pathway at a metabolic level. We used androgen dependent LNCaP cells cultured under steroid-depleted conditions and assessed the impact of vitamin D-based compounds upon intracrine pathways that convert exogenously added DHEA to relevant metabolites, through Mass Spectrometry (MS). Changes in relevant metabolism-related gene targets were also assessed. Our findings confirm that exposure to vitamin D based compounds, within LNCaP cells, elicits measurable and significant reduction in the intracrine conversion of DHEA to T, DHT and other intermediate metabolites within the androgenic pathway. The aassessment and validation of the biological model and analytical platforms were performed by pharmacological manipulations of the SRD5α and HSD-17β enzymes. The data provides further confirmation for how a vitamin D-based regime may be used to counter intracrine mechanisms contributing to the emergence of castrate-resistant tumors., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Published
2019
Full Text
View/download PDF

4. Derivatization of estrogens enhances specificity and sensitivity of analysis of human plasma and serum by liquid chromatography tandem mass spectrometry.

Author

Faqehi AMM, Cobice DF, Naredo G, Mak TCS, Upreti R, Gibb FW, Beckett GJ, Walker BR, Homer NZM, and Andrew R

Subjects
Adult, Aged, Aged, 80 and over, Benzenesulfonates chemistry, Estradiol chemistry, Estradiol isolation & purification, Estrogens chemistry, Estrogens isolation & purification, Estrone chemistry, Estrone isolation & purification, Female, Humans, Male, Middle Aged, Postmenopause, Premenopause blood, Pyridinium Compounds chemistry, Reproducibility of Results, Solid Phase Extraction, Spectrometry, Mass, Electrospray Ionization, Young Adult, Chromatography, Liquid methods, Estradiol blood, Estrogens blood, Estrone blood, Tandem Mass Spectrometry methods
Abstract

Estrogens circulate at concentrations less than 20pg/mL in men and postmenopausal women, presenting analytical challenges. Quantitation by immunoassay is unreliable at these low concentrations. Liquid chromatography tandem mass spectrometry (LC-MS/MS) offers greater specificity and sometimes greater sensitivity, but ionization of estrogens is inefficient. Introduction of charged moieties may enhance ionization, but many such derivatives of estrogens generate non-specific product ions originating from the "reagent" group. Therefore an approach generating derivatives with product ions specific to individual estrogens was sought. Estrogens were extracted from human plasma and serum using solid phase extraction and derivatized using 2-fluoro-1-methylpyridinium-p-toluenesulfonate (FMP-TS). Electrospray in positive mode with multiple reaction monitoring using a QTrap 5500 mass spectrometer was used to quantify "FMP" derivatives of estrogens, following LC separation. Transitions for the FMP derivatives of estrone (E1) and estradiol (E2) were compound specific (m/z 362→238 and m/z 364→128, respectively). The limits of detection and quantitation were 0.2pg on-column and the method was linear from 1-400pg/sample. Measures of intra- and inter-assay variability, precision and accuracy were acceptable (<20%). The derivatives were stable over 24h at 10°C (7-9% degradation). Using this approach, E1 and E2, respectively were detected in human plasma and serum: pre-menopausal female serum (0.5mL) 135-473, 193-722pmol/L; male plasma (1mL) 25-111, 60-180pmol/L and post-menopausal female plasma (2mL), 22-78, 29-50pmol/L. Thus FMP derivatization, in conjunction with LC-MS/MS, is suitable for quantitative analysis of estrogens in low abundance in plasma and serum, offering advantages in specificity over immunoassay and existing MS techniques., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Published
2016
Full Text
View/download PDF

5. Measurement of tamsulosin in human serum by liquid chromatography-tandem mass spectrometry.

Author

Upreti R, Homer NZ, Naredo G, Cobice DF, Hughes KA, Stewart LH, Walker BR, and Andrew R

Subjects
Adolescent, Adult, Drug Stability, Humans, Linear Models, Liquid-Liquid Extraction, Male, Middle Aged, Prostatic Hyperplasia, Reproducibility of Results, Sensitivity and Specificity, Sulfonamides chemistry, Tamsulosin, Chromatography, Liquid methods, Sulfonamides blood, Tandem Mass Spectrometry methods
Abstract

A simple, sensitive and robust method to extract tamsulosin from human serum, and quantify by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and validated and is applicable as a measure of compliance in clinical research. Tamsulosin was extracted from human serum (100μL) via liquid-liquid extraction with methyl tert-butyl ether (2mL) following dilution with 0.1M ammonium hydroxide (100μL), achieving 99.9% analyte recovery. Internal standard, d9-finasteride, was synthesised in-house. Analyte and internal standard were separated on an Ascentis(®) Express C18 (100mm×3mm, 2.7μm) column using a gradient elution with mobile phases methanol and 2mM aqueous ammonium acetate (5:95, v/v). Total run-time was 6min. Tamsulosin was quantified using a triple quadrupole mass spectrometer operated in multi-reaction-monitoring (MRM) mode using positive electrospray ionisation. Mass transitions monitored for quantitation were: tamsulosin m/z 409→228 and d9-finasteride m/z 382→318, with the structural formulae of ions confirmed by Fourier transform ion cyclotron resonance mass spectrometry (within 10ppm). The limit of quantitation was 0.2ng/mL, and the method was validated in the linear range 0.2-50ng/mL with acceptable inter- and intra-assay precision and accuracy and stability suitable for routine laboratory practice. The method was successfully applied to samples taken from research volunteers in a clinical study of benign prostatic hyperplasia., (Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.)

Published
2013
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results