404 results on '"A K, Burnett"'
Search Results
2. Upregulated microRNA-21 drives proliferation of lymphatic malformation endothelial cells by inhibiting PDCD4
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Ravi W. Sun, Haihong Zhang, Syed J. Mehdi, Gresham T. Richter, Hayden H. Bowman, Jessica Sifford, Chelsea Smith, Alexander K. Burnett, Alexander Layman, Charity L. Washam, Stephanie D. Byrum, James T. Bennett, Dana M. Jensen, Victoria Dmyterko, Jonathan A. Perkins, Carrie J. Shawber, June K. Wu, and Graham M. Strub
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Cell Biology ,Dermatology ,Molecular Biology ,Biochemistry - Published
- 2023
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3. Just write it down: Similarity in the benefit from cognitive offloading in young and older adults
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Lois K. Burnett and Lauren L. Richmond
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Neuropsychology and Physiological Psychology ,Arts and Humanities (miscellaneous) ,Experimental and Cognitive Psychology - Published
- 2023
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4. Therapy for isocitrate dehydrogenase 2 ( IDH2 ) R172 ‐mutant acute myeloid leukaemia
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David C. Linch, Robert K. Hills, Alan K. Burnett, Nigel Russell, and Rosemary E. Gale
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Hematology - Published
- 2021
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5. Randomized evaluation of quizartinib and low-dose ara-C vs low-dose ara-C in older acute myeloid leukemia patients
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Mhairi Copland, Ian Thomas, Nigel H. Russell, Richard E. Clark, Robert Kerrin Hills, Cono Ariti, Priyanka Mehta, Michael Dennis, Steven Knapper, Laura Upton, Rohini Radia, Amanda F. Gilkes, Claire Hemmaway, and Alan K. Burnett
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Oncology ,medicine.medical_specialty ,medicine.medical_treatment ,Population ,Targeted therapy ,chemistry.chemical_compound ,fluids and secretions ,Internal medicine ,hemic and lymphatic diseases ,medicine ,Humans ,Benzothiazoles ,education ,Quizartinib ,Aged ,Chemotherapy ,education.field_of_study ,business.industry ,Phenylurea Compounds ,Hazard ratio ,Cytarabine ,Myeloid leukemia ,hemic and immune systems ,Hematology ,Stimulus Report ,Confidence interval ,Clinical trial ,Leukemia, Myeloid, Acute ,chemistry ,embryonic structures ,business ,psychological phenomena and processes - Abstract
Key Points First report of an FLT3-targeted therapy added to nonintensive chemotherapy that has improved survival in older FLT3-ITD patients with AML.Quizartinib is well tolerated, improves response and survival in older FLT3-ITD AML patients and merits consideration in future therapies. Now amended as text above., Visual Abstract, Survival for older patients with acute myeloid leukemia (AML) unsuitable for intensive chemotherapy is unsatisfactory. Standard nonintensive therapies have low response rates and only extend life by a few months. Quizartinib is an oral Fms-like tyrosine kinase 3 (FLT3) inhibitor with reported activity in wild-type patients. As part of the AML LI trial, we undertook a randomized evaluation of low-dose ara-C (LDAC) with or without quizartinib in patients not fit for intensive chemotherapy. Overall, survival was not improved (202 patients), but in the 27 FLT3-ITD patients, the addition of quizartinib to LDAC improved response (P = .05) with complete remission/complete remission with incomplete haematological recovery for quizartinib + LDAC in 5/13 (38%) vs 0/14 (0%) in patients receiving LDAC alone. Overall survival (OS) in these FLT3-ITD+ patients was also significantly improved at 2 years for quizartinib + LDAC (hazard ratio 0.36; 95% confidence intervals: 0.16, 0.85, P = .04). Median OS was 13.7 months compared with 4.2 months with LDAC alone. This is the first report of an FLT3-targeted therapy added to standard nonintensive chemotherapy that has improved survival in this population. Quizartinib merits consideration for future triplet-based treatment approaches. This trial was registered at www.clinicaltrials.gov as ISRCTN #ISRCTN40571019 and EUDRACT @2011-000749-19.
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- 2021
6. A randomised evaluation of low-dose Ara-C plus pegylated recombinant arginase BCT-100 versus low dose Ara-C in older unfit patients with acute myeloid leukaemia: Results from the LI-1 trial
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Francis, Mussai, Carmela, De Santo, Paul, Cheng, Ian F, Thomas, Cono, Ariti, Laura, Upton, Ugo, Scarpa, Victoria, Stavrou, Mia, Sydenham, Alan K, Burnett, Steven K, Knapper, Priyanka, Mehta, Mary F, McMullin, Mhairi, Copland, Nigel H, Russell, and Mike, Dennis
- Abstract
The survival of acute myeloid leukaemia (AML) patients aged over 60 has been suboptimal historically, whether they are treated using hypomethylating agents, low-dose cytarabine (LDAC) or venetoclax-based regimens. Progress is being made, however, for subgroups with favourable molecular or cytogenetic findings. Arginine metabolism plays a key role in AML pathophysiology. We report the only randomised study of LDAC with recombinant arginase BCT-100 versus LDAC alone in older AML patients unsuitable for intensive therapy. Eighty-three patients were randomised to the study. An overall response rate was seen in 19.5% (all complete remission [CR]) and 15% (7.5% each in CR and CR without evidence of adequate count recovery [CRi]) of patients in the LDAC+BCT-100 and LDAC arms respectively (odds ratio 0.73, confidence interval 0.23-2.33; p = 0.592). No significant difference in overall or median survival between treatment arms was seen. The addition of BCT-100 to LDAC was well tolerated.
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- 2022
7. Early mortality risk with non-intensive acute myeloid leukemia (AML) therapies: analysis of 1336 patients from MRC/NCRI and SWOG
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Megan Othus, Ian Thomas, Xu Wang, Cono Ariti, Priyanka Mehta, Mia Sydenham, Robert K. Hills, Alan K. Burnett, Sucha Nand, Sarit Assouline, Laura C. Michaelis, Harry P. Erba, Nigel Russell, Kathleen F. Kerr, Roland B. Walter, and Mike Dennis
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Cancer Research ,Oncology ,Hematology - Published
- 2022
8. Performance on the processing portion of complex working memory span tasks is related to working memory capacity estimates
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B. Hunter Ball, Lauren L. Richmond, Alexandra B. Morrison, and Lois K Burnett
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Computer science ,Working memory ,media_common.quotation_subject ,Attentional control ,Experimental and Cognitive Psychology ,Cognition ,Fluid intelligence ,Span (engineering) ,Task (project management) ,Arts and Humanities (miscellaneous) ,Component (UML) ,Developmental and Educational Psychology ,Psychology (miscellaneous) ,Function (engineering) ,General Psychology ,media_common ,Cognitive psychology - Abstract
Individual differences in working memory capacity (WMC) have long been known to relate to performance in domains outside of WM, including attentional control, long-term memory, problem-solving, and fluid intelligence to name a few. Complex span WM tasks, composed of a processing component and a storage component, are often used to index WMC in these types of investigations. Capacity estimates are derived from performance on the storage component only, while processing performance is often largely ignored. Here, we explore the relationship between processing performance and WMC in a large dataset for each of three complex span tasks to better characterize how the components of these tasks might be related. We provide evidence that enforcing an 85% or better accuracy criterion for the processing portion of the task results in the removal of a disproportionate number of individuals exhibiting lower WMC estimates. We also find broad support for differences in processing task performance, characterized according to both accuracy and reaction time metrics, as a function of WMC. We suggest that researchers may want to include processing task performance measures, in addition to capacity estimates, in studies using complex span tasks to index WMC. This approach may better characterize the relationships between complex span task performance and performance in disparate domains of cognition.
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- 2021
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9. Unified classification and risk-stratification in Acute Myeloid Leukemia
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Yanis Tazi, Juan E. Arango-Ossa, Yangyu Zhou, Elsa Bernard, Ian Thomas, Amanda Gilkes, Sylvie Freeman, Yoann Pradat, Sean J. Johnson, Robert Hills, Richard Dillon, Max F. Levine, Daniel Leongamornlert, Adam Butler, Arnold Ganser, Lars Bullinger, Konstanze Döhner, Oliver Ottmann, Richard Adams, Hartmut Döhner, Peter J. Campbell, Alan K. Burnett, Michael Dennis, Nigel H. Russell, Sean M. Devlin, Brian J. P. Huntly, Elli Papaemmanuil, Tazi, Yanis [0000-0002-1595-9631], Bernard, Elsa [0000-0002-2057-7187], Freeman, Sylvie [0000-0003-1869-180X], Pradat, Yoann [0000-0002-4647-5779], Dillon, Richard [0000-0001-9333-5296], Levine, Max F [0000-0001-5156-9086], Leongamornlert, Daniel [0000-0002-3486-3168], Döhner, Konstanze [0000-0002-2261-9862], Adams, Richard [0000-0003-3915-7243], Döhner, Hartmut [0000-0003-2116-5536], Campbell, Peter J [0000-0002-3921-0510], Burnett, Alan K [0000-0003-1734-5817], Devlin, Sean M [0000-0002-6801-720X], Huntly, Brian JP [0000-0003-0312-161X], Papaemmanuil, Elli [0000-0003-1709-8983], and Apollo - University of Cambridge Repository
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Cancer Research ,Multidisciplinary ,Neoplasm, Residual ,article ,General Physics and Astronomy ,General Chemistry ,631/67/69 ,Induction Chemotherapy ,Flow Cytometry ,General Biochemistry, Genetics and Molecular Biology ,Leukemia, Myeloid, Acute ,Cytogenetic Analysis ,Humans ,692/4028/67/1990/283/1897 ,631/208/69 - Abstract
Funder: E.P. is a Josie Robertson Investigator and is supported by the European Hematology Association, American Society of Hematology, Gabrielle’s Angels Foundation, V Foundation and The Geoffrey Beene Foundation and is a Damon Runyon Rachleff Innovator fellow. Work in the BJPH lab is funded by Cancer Research UK (C18680/A25508), the European Research Council (647685), MRC (MR-R009708-1), the Kay Kendall Leukaemia Fund (KKL1243), the Wellcome Trust (205254/Z/16/Z) and the Cancer Research UK Cambridge Major Centre (C49940/A25117). This research was supported by the NIHR Cambridge Biomedical Research Centre (BRC-1215-20014), and was funded in part, by the Wellcome Trust who supported the Wellcome - MRC Cambridge Stem Cell Institute (203151/Z/16/Z). The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care. L.B., H.D. and B.J.P.H. are supported by the HARMONY Alliance (IMI Project No. 116026; https://www.harmony-alliance.eu/). The UK-NCRI AML working group trials were supported with research grants from the Medical Research Council (MRC), Cancer Research UK (CRUK), Blood Cancer UK and Cardiff University. We would like to thank all patients and investigators for their participation in the trials and the study., Clinical recommendations for Acute Myeloid Leukemia (AML) classification and risk-stratification remain heavily reliant on cytogenetic findings at diagnosis, which are present in
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- 2022
10. AML: New Drugs but New Challenges
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Alan K. Burnett and Richard Stone
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0301 basic medicine ,Oncology ,Cancer Research ,medicine.medical_specialty ,Daunorubicin ,Gemtuzumab ozogamicin ,medicine.medical_treatment ,Disease ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Humans ,Chemotherapy ,Aniline Compounds ,Venetoclax ,business.industry ,Phenylurea Compounds ,Cytarabine ,Myeloid leukemia ,Hematology ,Gemtuzumab ,Leukemia, Myeloid, Acute ,030104 developmental biology ,Clinical research ,chemistry ,Pyrazines ,030220 oncology & carcinogenesis ,Benzimidazoles ,business ,medicine.drug - Abstract
Despite the approval of 8 new drugs for acute myeloid leukemia (AML) since 2017, the disease remains challenging, given the significant toxicity associated with available treatments and relatively low cure rates, especially in older adults. Although advantageous for patients, self-congratulatory rejoicing about the new agents would be extremely premature. Questions abound about the need for a specific versus less specific FLT3 inhibitor (eg, midostautin) in the upfront setting and whether a single agent (gilteritnib), albeit better than chemotherapy, is sufficient for relapsed disease. Is the new liposomal formulation of daunorubicin/cytarabine better than ‘3 + 7’ only in secondary AML? Should only those newly diagnosed patients with core binding factor AML routinely receive gemtuzumab ozogamicin? The isocitrate dehydrogenase inhibitors were approved based on non-randomized data; thus, one wonders whether single-agent isocitrate dehydrogenase inhibitor therapy is appropriate for relapsed patients. Glasdegib, an orally available hedgehog inhibitor, is approved in conjunction with low-dose cytarabine in unfit patients but is rarely used in favor of a combination of hypomethylating agents or low-dose cytarabine with venetoclax, which are hopeful newly approved combinations for the older and/or unfit previously untreated. Perhaps venetoclax-based combinations should be more widely used, but the data is currently lacking. Thus, a temperate approach, more clinical research, and a critical analysis of the available data remain important in this “optimistic” new era of AML therapeutics.
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- 2020
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11. Rubrene single crystal solar cells and the effect of crystallinity on interfacial recombination
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Duygu Akin Kara, Edmund K. Burnett, Koray Kara, Ozlem Usluer, Benjamin P. Cherniawski, Edward J. Barron, Burak Gultekin, Mahmut Kus, and Alejandro L. Briseno
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Morphology ,Mobility ,Open-Circuit Voltage ,Temperature ,General Physics and Astronomy ,Transport ,Order ,Growth ,Physical and Theoretical Chemistry ,Films - Abstract
Single crystal studies provide a better understanding of the basic properties of organic photovoltaic devices. Therefore, in this work, rubrene single crystals with a thickness of 250 nm to 1000 nm were used to produce an inverted bilayer organic solar cell. Subsequently, polycrystalline rubrene (orthorhombic, triclinic) and amorphous bilayer solar cells of the same thickness as single crystals were studied to make comparisons across platforms. To investigate how single crystal, polycrystalline (triclinic-orthorhombic) and amorphous forms alter the charge carrier recombination mechanism at the rubrene/PCBM interface, light intensity measurements were carried out. The light intensity dependency of the J(SC), V-OC and FF parameters in organic solar cells with different forms of rubrene was determined. Monomolecular (Shockley Read Hall) recombination is observed in devices employing amorphous and polycrystalline rubrene in addition to bimolecular recombination, whereas the single crystal device is weakly affected by trap assisted SRH recombination due to reduced trap states at the donor acceptor interface. To date, the proposed work is the only systematic study examining transport and interface recombination mechanisms in organic solar cells produced by different structure forms of rubrene., Office of Naval Research [N0001416-1-2612, N000147-14-1-0053]; Turkey research fellowship [TUBITAK 2214/A-1059B141501315]; Turkey Scholarship Council [2214/A-1059B141501316]; 1003 -Primary Subjects R&D Funding Program [218M940], D. A. K. acknowledges the Turkey research fellowship (TUBITAK 2214/A-1059B141501315). K. K. thanks the Turkey Scholarship Council (2214/A-1059B141501316). B. G acknowledges the 1003 -Primary Subjects R&D Funding Program (218M940) and A. L. B. acknowledges the Office of Naval Research (N0001416-1-2612 and N000147-14-1-0053).
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- 2022
12. A randomised comparison of FLAG-Ida versus daunorubicin combined with clofarabine in relapsed or refractory acute myeloid leukaemia: Results from the UK NCRI AML17 trial
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Nigel H. Russell, Robert K. Hills, Lars Kjeldsen, Richard E. Clark, Sahra Ali, Paul Cahalin, Ian F. Thomas, and Alan K. Burnett
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Leukemia, Myeloid, Acute ,Antineoplastic Combined Chemotherapy Protocols ,Chronic Disease ,Daunorubicin ,Granulocyte Colony-Stimulating Factor ,Cytarabine ,Humans ,Hematology ,Idarubicin ,United Kingdom ,Vidarabine ,Clofarabine - Abstract
The prognosis for younger patients with relapsed acute myeloid leukaemia (AML) is generally dismal. Allogeneic stem cell transplantation is the preferred therapy for these patients. As part of the UK NCRI AML17 trial, daunorubicin/clofarabine (DClo) was compared with fludarabine, cytarabine, granulocyte colony-stimulating factor with idarubicin (FLAG-Ida) in 311 patients designated high-risk following course one of induction therapy, which has previously been reported. We now report the results of the same randomisation in patients who were refractory to two induction courses or subsequently relapsed. A total of 94 relapsed or refractory AML patients, usually less than 60 years of age and with mainly favourable or intermediate-risk cytogenetics, were randomised to receive up to three courses of DClo or FLAG-Ida, with the aim of proceeding to transplant. Complete remission was achieved in 74% of patients with no difference between the arms. Overall, 57% of patients received a transplant with no difference between the arms, likewise overall survival at five years showed no significant difference (21% for DClo vs. 22% for FLAG-Ida). No patient who did not receive a transplant survived beyond 21months. A stratified analysis including the 311 post course 1 high-risk patients who underwent the same randomisation showed a consistent treatment benefit for FLAG-Ida.
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- 2022
13. 4CPS-008 The role of the pharmacist in the management of intravenous fluids and electrolytes in adult patients
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R O’Hare, K Burnett, S Haughey, C Angela, and L Edgar
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- 2022
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14. P31 Analgesia and anaesthesia study day for undergraduate midwives
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K. Burnett, C. Robinson, S. Smith, and K. Maclennan
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Anesthesiology and Pain Medicine ,Obstetrics and Gynecology - Published
- 2023
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15. Characterizing older adults’ real world memory function using ecologically valid approaches
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Lauren L. Richmond and Lois K. Burnett
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- 2022
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16. Author Correction: Genome-wide association study identifies susceptibility loci for acute myeloid leukemia
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Wei-Yu Lin, Sarah E. Fordham, Eric Hungate, Nicola J. Sunter, Claire Elstob, Yaobo Xu, Catherine Park, Anne Quante, Konstantin Strauch, Christian Gieger, Andrew Skol, Thahira Rahman, Lara Sucheston-Campbell, Junke Wang, Theresa Hahn, Alyssa I. Clay-Gilmour, Gail L. Jones, Helen J. Marr, Graham H. Jackson, Tobias Menne, Mathew Collin, Adam Ivey, Robert K. Hills, Alan K. Burnett, Nigel H. Russell, Jude Fitzgibbon, Richard A. Larson, Michelle M. Le Beau, Wendy Stock, Olaf Heidenreich, Abrar Alharbi, David J. Allsup, Richard S. Houlston, Jean Norden, Anne M. Dickinson, Elisabeth Douglas, Clare Lendrem, Ann K. Daly, Louise Palm, Kim Piechocki, Sally Jeffries, Martin Bornhäuser, Christoph Röllig, Heidi Altmann, Leo Ruhnke, Desiree Kunadt, Lisa Wagenführ, Heather J. Cordell, Rebecca Darlay, Mette K. Andersen, Maria C. Fontana, Giovanni Martinelli, Giovanni Marconi, Miguel A. Sanz, José Cervera, Inés Gómez-Seguí, Thomas Cluzeau, Chimène Moreilhon, Sophie Raynaud, Heinz Sill, Maria Teresa Voso, Francesco Lo-Coco, Hervé Dombret, Meyling Cheok, Claude Preudhomme, Rosemary E. Gale, David Linch, Julia Gaal-Wesinger, Andras Masszi, Daniel Nowak, Wolf-Karsten Hofmann, Amanda Gilkes, Kimmo Porkka, Jelena D. Milosevic Feenstra, Robert Kralovics, David Grimwade, Manja Meggendorfer, Torsten Haferlach, Szilvia Krizsán, Csaba Bödör, Friedrich Stölzel, Kenan Onel, and James M. Allan
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Multidisciplinary ,Genotype ,Science ,General Physics and Astronomy ,Reproducibility of Results ,General Chemistry ,Middle Aged ,Polymorphism, Single Nucleotide ,General Biochemistry, Genetics and Molecular Biology ,Acute myeloid leukaemia ,White People ,Leukemia, Myeloid, Acute ,Risk factors ,Aldehyde Reductase ,HLA Antigens ,Case-Control Studies ,Cancer genomics ,Humans ,Genetic Predisposition to Disease ,Author Correction ,Genome-Wide Association Study - Abstract
Acute myeloid leukemia (AML) is a hematological malignancy with an undefined heritable risk. Here we perform a meta-analysis of three genome-wide association studies, with replication in a fourth study, incorporating a total of 4018 AML cases and 10488 controls. We identify a genome-wide significant risk locus for AML at 11q13.2 (rs4930561; P = 2.15 × 10
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- 2022
17. Therapy for isocitrate dehydrogenase 2 (IDH2)
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David C, Linch, Robert K, Hills, Alan K, Burnett, Nigel, Russell, and Rosemary E, Gale
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Adult ,Cohort Studies ,Leukemia, Myeloid, Acute ,Mutation ,Humans ,Prognosis ,Isocitrate Dehydrogenase - Abstract
Although we earlier reported a very poor outcome for younger adult patients with isocitrate dehydrogenase 2 (IDH2)
- Published
- 2021
18. Genome-wide association study identifies susceptibility loci for acute myeloid leukemia
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Anne M. Dickinson, Gail Jones, David C. Linch, Clare Lendrem, David Grimwade, Richard A. Larson, Andrew D. Skol, Yaobo Xu, Adam Ivey, Wei-Yu Lin, Manja Meggendorfer, Rosemary E. Gale, Inés Gómez-Seguí, Giovani Marconi, Jean Norden, Jude Fitzgibbon, Mette K. Andersen, M Bornhäuser, Sarah E. Fordham, Amanda F. Gilkes, Heinz Sill, Eric A. Hungate, José Cervera, Friedrich Stölzel, Julia Gaal-Wesinger, Kim Piechocki, Wendy Stock, Theresa Hahn, Konstantin Strauch, David Allsup, Kenan Onel, Claire Elstob, Alyssa I. Clay-Gilmour, Nicola J. Sunter, Jelena D. Milosevic Feenstra, Meyling Cheok, Abrar Alharbi, Ann K. Daly, Sally Jeffries, Lisa Wagenführ, Olaf Heidenreich, Robert Kralovics, Alan K. Burnett, Giovanni Martinelli, Desiree Kunadt, Christian Gieger, Francesco Lo-Coco, Leo Ruhnke, Maria Teresa Voso, Junke Wang, Catherine Park, Nigel H. Russell, Chimène Moreilhon, Robert Kerrin Hills, Claude Preudhomme, Graham Jackson, Daniel Nowak, Maria Chiara Fontana, James M. Allan, Heidi Altmann, Richard S. Houlston, Anne S. Quante, Michelle M. Le Beau, Thahira Rahman, Christoph Röllig, Rebecca Darlay, Sophie Raynaud, Helen Marr, Csaba Bödör, Louise Palm, Thomas Cluzeau, Szilvia Krizsán, Heather J. Cordell, Mathew Collin, Torsten Haferlach, Lara E. Sucheston-Campbell, Wolf-Karsten Hofmann, Kimmo Porkka, Andras Masszi, Hervé Dombret, Miguel A. Sanz, Elisabeth Douglas, Tobias Menne, HUS Comprehensive Cancer Center, University Management, Helsinki University Hospital Area, Department of Oncology, and Hematologian yksikkö
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Oncology ,General Physics and Astronomy ,Genome-wide association study ,Disease ,0302 clinical medicine ,AML ,HLA Antigens ,hemic and lymphatic diseases ,Histone methylation ,Cancer genomics ,RISK ,0303 health sciences ,Multidisciplinary ,Myeloid leukemia ,Middle Aged ,CLONAL EVOLUTION ,CANCER ,3. Good health ,HLA ,Leukemia, Myeloid, Acute ,030220 oncology & carcinogenesis ,GENE-MUTATIONS ,medicine.medical_specialty ,Genotype ,Science ,Locus (genetics) ,HIF-1-ALPHA ,Human leukocyte antigen ,Polymorphism, Single Nucleotide ,Article ,Acute myeloid leukaemia ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Aldehyde Reductase ,Internal medicine ,medicine ,Humans ,Genetic Predisposition to Disease ,030304 developmental biology ,Genetic association ,OLDER PATIENTS ,Whites ,business.industry ,HUMAN-LEUKOCYTE ANTIGEN ,Reproducibility of Results ,Cancer ,General Chemistry ,Settore MED/15 ,medicine.disease ,IMMUNE ESCAPE ,Risk factors ,Case-Control Studies ,3111 Biomedicine ,business ,Genome-Wide Association Study - Abstract
Acute myeloid leukemia (AML) is a hematological malignancy with an undefined heritable risk. Here we perform a meta-analysis of three genome-wide association studies, with replication in a fourth study, incorporating a total of 4018 AML cases and 10488 controls. We identify a genome-wide significant risk locus for AML at 11q13.2 (rs4930561; P = 2.15 × 10−8; KMT5B). We also identify a genome-wide significant risk locus for the cytogenetically normal AML sub-group (N = 1287) at 6p21.32 (rs3916765; P = 1.51 × 10−10; HLA). Our results inform on AML etiology and identify putative functional genes operating in histone methylation (KMT5B) and immune function (HLA)., Genome wide association studies in cancer are used to understand the heritable genetic contribution to disease risk. Here, the authors perform a genome wide association study in European patients with acute myeloid leukemia and identify loci associated with risk of developing the disease.
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- 2021
19. Twenty five years of UK trials in acute myeloid leukaemia: what have we learned?
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Robert Kerrin Hills, Alan K. Burnett, and Nigel H. Russell
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Male ,Oncology ,Clinical Trials as Topic ,medicine.medical_specialty ,Myeloid ,business.industry ,Hematology ,History, 20th Century ,medicine.disease ,History, 21st Century ,United Kingdom ,Leukemia, Myeloid, Acute ,Leukemia ,medicine.anatomical_structure ,Internal medicine ,medicine ,Humans ,Female ,Acute promyelocytic leukaemia ,Myeloid leukaemia ,business ,Aged - Published
- 2019
- Full Text
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20. Even–Odd Alkyl Chain-Length Alternation Regulates Oligothiophene Crystal Structure
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Benjamin P. Cherniawski, Qianxiang Ai, Sean Parkin, Edmund K. Burnett, Chad Risko, and Alejandro L. Briseno
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chemistry.chemical_classification ,Steric effects ,Chemistry ,General Chemical Engineering ,Alternation (geometry) ,02 engineering and technology ,General Chemistry ,Crystal structure ,Chromophore ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Chain length ,Crystallography ,Materials Chemistry ,lipids (amino acids, peptides, and proteins) ,Solubility ,0210 nano-technology ,Alkyl - Abstract
Alkyl chains of varied length and steric bulk are generally appended to π-conjugated chromophores to increase solubility. These alkyl chains also regulate many aspects of the solid-state packing an...
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- 2019
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21. Genome-wide association study identifies susceptibility loci for acute myeloid leukemia
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Michelle M. Le Beau, Thahira Rahman, Yaobo Xu, Wendy Stock, Andrew D. Skol, Abrar Alharbi, David Allsup, Claire Elstob, Lara E. Sucheston-Campbell, Lisa Wagenführ, Olaf Heidenreich, Claude Preudhomme, Tobias Menne, Szilvia Krizsán, Rebecca Darlay, Jelena D. Milosevic Feenstra, David C. Linch, Sophie Raynaud, Helen Marr, Christian Gieger, Francesco Lo-Coco, David Grimwade, Maria Teresa Voso, Junke Wang, Christoph Röllig, Clare Lendrem, Wolf-Karsten Hofmann, Mathew Collin, Manja Meggendorfer, Friedrich Stölzel, Wei-Yu Lin, Ann K. Daly, Theresa Hahn, Torsten Haferlach, Sally Jeffries, Julia Gaal-Wesinger, Konstantin Strauch, Giovani Marconi, Amanda F. Gilkes, Chimène Moreilhon, Giovanni Martinelli, Anne M. Dickinson, Robert Kerrin Hills, Alan K. Burnett, Mette K. Andersen, Leo Ruhnke, Kimmo Porkka, Catherine Park, Desiree Kunadt, Nigel H. Russell, M Bornhäuser, Alyssa I. Clay-Gilmour, Hervé Dombret, Sarah E. Fordham, Eric A. Hungate, Miguel A. Sanz, Inés Gómez-Seguí, Csaba Bödör, Jean Norden, Elisabeth Douglas, Rosemary E. Gale, Heinz Sill, Kim Piechocki, Richard A. Larson, Robert Kralovics, Meyling Cheok, Heidi Altmann, Richard S. Houlston, Andras Masszi, Anne S. Quante, Louise Palm, Thomas Cluzeau, Heather J. Cordell, Nicola J. Sunter, Graham Jackson, Daniel Nowak, Maria Chiara Fontana, James M. Allan, José Cervera, Kenan Onel, Gail Jones, Adam Ivey, and Jude Fitzgibbon
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0303 health sciences ,Myeloid leukemia ,Locus (genetics) ,Genome-wide association study ,Human leukocyte antigen ,Biology ,3. Good health ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,030220 oncology & carcinogenesis ,Histone methylation ,Cancer research ,Etiology ,030304 developmental biology ,Genetic association - Abstract
Acute myeloid leukemia (AML) is a hematological malignancy with an undefined heritable risk. Here we performed a meta-analysis of three genome-wide association studies, with replication in a fourth study, incorporating a total of 4018 AML cases and 10488 controls. We identified a genome-wide significant risk locus for AML at 11q13.2 (rs4930561; P = 2.15 × 10-8; KMT5B). We also identified a genome-wide significant risk locus for the cytogenetically normal AML sub-group (N=1287) at 6p21.32 (rs3916765; P = 1.51 × 10-10; HLA). Our results inform on AML etiology by identifying putative functional genes operating in histone methylation (KMT5B) and immune function (HLA).
- Published
- 2021
- Full Text
- View/download PDF
22. Less Intensive 1 (LI1) Trial: A Randomized Phase II/III Clinical Trial in Approximately 1000 Elderly Patients With Acute Myeloid Leukaemia (AML) Deemed Not Suitable for Intensive Chemotherapy
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R Hills, Cono Ariti, Michael Dennis, N Russell, Ian Thomas, Alan K. Burnett, Laura Upton, and Mhairi Copland
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Clinical trial ,Oncology ,medicine.medical_specialty ,Text mining ,business.industry ,Internal medicine ,Medicine ,Intensive chemotherapy ,Myeloid leukaemia ,business - Abstract
BackgroundAcute myeloid leukaemia (AML) is a heterogeneous disease where outcome is substantially influenced by age. Over the last 30-40 years, significant improvements have been made in survival for younger patients (those under 60). However, with the median age of the disease at diagnosis at 65 years, outcome in older patients has improved much less. Additionally, many elderly patients are not considered suitable for intensive chemotherapy and the current standard treatment is considered unsatisfactory. MethodsLI1 will evaluate several relevant therapeutic questions in AML patients over 60 years of age for whom intensive chemotherapy is not considered suitable. Patients are invited to enter a randomized comparison of standard therapy (LD Ara-C) versus a novel treatment. A number of different treatment options are available at any one time, but there is no comparison between novel agents. If, at initial review, a novel agent is deemed unlikely to demonstrate the required improvement, it may be removed from the protocol and replaced with another novel agent, via protocol amendment. Agents are initially entered into a phase II comparison against standard of care - where an agent is considered promising at interim review (based on remission rates), the randomisation may be extended to a fully powered phase III comparison based on survival. Agents which may prolong survival or improve remission rates will also be required to demonstrate equivalence or better of quality of life in patients – therefore, quality of life assessments are undertaken throughout, in each arm. DiscussionEven when less intensive treatment options are delivered, the outcomes are not satisfactory. The NCRI AML working group has a strong network, required for delivery of this trial program. The UK network is augmented by international collaborative groups, most notably from New Zealand and Denmark. The use of the Pick-a-Winner design improves efficiency and speed of review of the available novel agents with the aim of benefitting the increasing number of patients in this age group.Trial registration: ISCRTN40571019, EUDRACT2011-000479-19 (12th May 2011)
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- 2021
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23. Protocorm-Supporting Fungi Are Retained in Roots of Mature Tipularia discolor Orchids as Mycorrhizal Fungal Diversity Increases
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Robert K. Burnett, Melissa K. McCormick, and Dennis F. Whigham
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0106 biological sciences ,orchid mycorrhizae ,Plant Science ,010603 evolutionary biology ,01 natural sciences ,Article ,Fungal Diversity ,Mycorrhizal fungi ,Botany ,Temperate climate ,Orchidaceae ,protocorm fungi ,Ecology, Evolution, Behavior and Systematics ,Abiotic component ,Ecology ,biology ,fungi ,mycorrhizal diversity ,Tipularia discolor ,Substrate (biology) ,biology.organism_classification ,Germination ,QK1-989 ,010606 plant biology & botany - Abstract
Mycorrhizal fungi are critical to understanding the distribution patterns of many plants, but they are especially important for orchids. Some orchids may change the mycorrhizal fungi they use through their lives, either in response to changes in abiotic or biotic conditions, or as a result of ontogenetic changes that alter the orchid’s need for fungal nutrition. The temperate terrestrial orchid Tipularia discolor germinates only on decomposing wood, but often persists well after the wood has completely decomposed and has been incorporated into the soil. We used PCR and Sanger sequencing to ask: (1) Do mature T. discolor retain protocorm fungi or are protocorm and adult mycorrhizal fungi mutually exclusive? (2) Are protocorm fungi limited to areas with decomposing wood? (3) Does the abundance of protocorm fungi in the substrate differ between decomposing wood and bare soil? We found that T. discolor retained protocorm fungi into maturity, regardless of whether they were growing in persistent decomposing wood or soil. Protocorm fungi were not restricted to decomposing wood but were more common and abundant in it. We conclude that the mycorrhizal fungi associated with T. discolor change during the ontogeny of individuals. These results highlight the importance of assessing protocorm fungi, in addition to mycorrhizal fungi associating with adult orchids, to understand the conditions needed for orchid germination, growth, and reproduction.
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- 2021
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24. Performance on the processing portion of complex working memory span tasks is related to working memory capacity estimates
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Lauren L, Richmond, Lois K, Burnett, Alexandra B, Morrison, and B Hunter, Ball
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Memory, Short-Term ,Intelligence ,Reaction Time ,Humans ,Attention ,Problem Solving - Abstract
Individual differences in working memory capacity (WMC) have long been known to relate to performance in domains outside of WM, including attentional control, long-term memory, problem-solving, and fluid intelligence to name a few. Complex span WM tasks, composed of a processing component and a storage component, are often used to index WMC in these types of investigations. Capacity estimates are derived from performance on the storage component only, while processing performance is often largely ignored. Here, we explore the relationship between processing performance and WMC in a large dataset for each of three complex span tasks to better characterize how the components of these tasks might be related. We provide evidence that enforcing an 85% or better accuracy criterion for the processing portion of the task results in the removal of a disproportionate number of individuals exhibiting lower WMC estimates. We also find broad support for differences in processing task performance, characterized according to both accuracy and reaction time metrics, as a function of WMC. We suggest that researchers may want to include processing task performance measures, in addition to capacity estimates, in studies using complex span tasks to index WMC. This approach may better characterize the relationships between complex span task performance and performance in disparate domains of cognition.
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- 2021
25. Vibration Suppression of a Composite Prosthetic Foot Using Piezoelectric Shunt Damping: Implications to Vibration-Induced Cumulative Trauma
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Ross H. Miller, Jenna K. Burnett, Norman M. Wereley, Young T. Choi, Jae Kun Shim, and Hua Li
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Materials science ,Foot ,Modal analysis ,Acoustics ,Composite number ,Biomedical Engineering ,Artificial Limbs ,Walking ,Piezoelectricity ,Vibration ,Finite element method ,Amputees ,Bending moment ,Humans ,Shunt (electrical) ,Electronic circuit - Abstract
Objective: Energy-storage-and-return (ESAR) prosthetic feet have improved amputee mobility due to their efficient conversion of strain energy to mechanical work. However, this efficiency is typically achieved using light-weight, high-stiffness materials, which generate high-frequency vibrations that are potentially injurious if transmitted to biological tissues. To reduce the vibration which may cause cumulative tissue trauma, high-frequency vibration suppression by piezoelectric shunt damping patches on a commercial ESAR foot was evaluated. Methods: Two patches with either passive or active shunt circuits were placed on the foot to investigate vibration suppression during experimental tests where a plastic hammer was used to hit a clamped ESAR foot on the free end. Prosthesis bending moments at each modal frequency were obtained by finite element methods to identify piezoelectric patch placement. Results: Both shunt circuits decreased vibration amplitudes at specific modes better than the no shunt case, but also increased the amplitude at specific frequencies. The vibration suppression performance of the active shunt circuit deteriorated at the second mode, while the vibration suppression performance of the passive shunt circuit deteriorated at all frequencies above the third mode. Conclusions: These results indicate piezoelectric shunt patches may be a viable strategy for decreasing vibrations of an ESAR foot, with active methods more efficient at suppressing high-frequency vibrations. Additional research is necessary to fine-tune the method for maximal vibration suppression. Significance: Overall, this study indicates that high-frequency vibration suppression is possible using piezoelectric patches, possibly decreasing the cumulative tissue damage that may occur with repetitive exposure to vibration.
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- 2021
26. Management of acute promyelocytic leukemia: updated recommendations from an expert panel of the European LeukemiaNet
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Giuseppe Avvisati, Farhad Ravandi, Uwe Platzbecker, Alan K. Burnett, Pau Montesinos, Elihu H. Estey, Miguel A. Sanz, Harry J. Iland, Pierre Fenaux, Eduardo Magalhães Rego, Eva Lengfelder, Hagop M. Kantarjian, Hartmut Döhner, Bob Löwenberg, Vikram Mathews, Lionel Adès, Nigel H. Russell, Martin S. Tallman, Tomoki Naoe, Sai Juan Chen, Francesco Lo-Coco, and Hematology
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Acute promyelocytic leukemia ,medicine.medical_specialty ,medicine.medical_treatment ,Immunology ,MEDLINE ,Tretinoin ,Disease ,Hemorrhagic Disorders ,Biochemistry ,Hemorrhagic disorder ,European LeukemiaNet ,Arsenic Trioxide ,Leukemia, Promyelocytic, Acute ,Pregnancy ,Recurrence ,Humans ,Medicine ,Disease management (health) ,Intensive care medicine ,Special Report ,Neoadjuvant therapy ,APL Differentiation Syndrome ,Aged ,business.industry ,Disease Management ,Cell Biology ,Hematology ,medicine.disease ,Practice Guidelines as Topic ,Female ,business - Abstract
Since the comprehensive recommendations for the management of acute promyelocytic leukemia (APL) reported in 2009, several studies have provided important insights, particularly regarding the role of arsenic trioxide (ATO) in frontline therapy. Ten years later, a European LeukemiaNet expert panel has reviewed the recent advances in the management of APL in both frontline and relapse settings in order to develop updated evidence- and expert opinion–based recommendations on the management of this disease. Together with providing current indications on genetic diagnosis, modern risk-adapted frontline therapy, and salvage treatment, the review contains specific recommendations for the identification and management of the most important complications such as the bleeding disorder APL differentiation syndrome, QT prolongation, and other all-trans retinoic acid– and ATO-related toxicities, as well as recommendations for molecular assessment of the response to treatment. Finally, the approach to special situations is also discussed, including management of APL in children, elderly patients, and pregnant women. The most important challenges remaining in APL include early death, which still occurs before and during induction therapy, and optimizing treatment in patients with high-risk disease.
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- 2019
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27. Efficient Electron Mobility in an All-Acceptor Napthalenediimide-Bithiazole Polymer Semiconductor with Large Backbone Torsion
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Soohyung Park, Jean-Luc Brédas, Yao Liu, Yeonjin Yi, Todd Emrick, Alejandro L. Briseno, Simil Thomas, Stephen J. Rosa, Thomas P. Russell, Edmund K. Burnett, Jack Ly, Areej Aljarb, and Hyunbok Lee
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chemistry.chemical_classification ,Diffraction ,Electron mobility ,Materials science ,business.industry ,02 engineering and technology ,Polymer ,Dihedral angle ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Acceptor ,0104 chemical sciences ,chemistry.chemical_compound ,Crystallography ,Semiconductor ,chemistry ,General Materials Science ,Density functional theory ,0210 nano-technology ,Thiazole ,business - Abstract
An all-acceptor napthalenediimide-bithiazole-based co-polymer, P(NDI2OD-BiTz), was synthesized and characterized for application in thin-film transistors. Density functional theory calculations point to an optimal perpendicular dihedral angle of 90° between acceptor units along isolated polymer chains; yet optimized transistors yield electron mobility of 0.11 cm2/(V s) with the use of a zwitterionic naphthalene diimide interlayer. Grazing incidence X-ray diffraction measurements of annealed films reveal that P(NDI2OD-BiTz) adopts a highly ordered edge-on orientation, exactly opposite to similar bithiophene analogs. This report highlights an NDI and thiazole all-acceptor polymer and demonstrates high electron mobility despite its nonplanar backbone conformation.
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- 2018
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28. Correlating Crystal Thickness, Surface Morphology, and Charge Transport in Pristine and Doped Rubrene Single Crystals
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Natalie Stingelin, D. Leonardo Gonzalez Arellano, Guillaume Wantz, Cédric Ayela, Edmund K. Burnett, Stefan Bachevillier, Stefan C. B. Mannsfeld, Jae Joon Kim, Özlem Usluer, Alejandro L. Briseno, Benjamin P. Cherniawski, Laboratoire de l'intégration, du matériau au système (IMS), Université Sciences et Technologies - Bordeaux 1-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie des Polymères Organiques (LCPO), Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Ecole Nationale Supérieure de Chimie, de Biologie et de Physique (ENSCBP)-Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC), Stanford Synchrotron Radiation Lightsource (SSRL SLAC), SLAC National Accelerator Laboratory (SLAC), and Stanford University-Stanford University
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Surface (mathematics) ,Materials science ,Morphology (linguistics) ,Doping ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Subthreshold slope ,0104 chemical sciences ,Crystal ,[SPI]Engineering Sciences [physics] ,chemistry.chemical_compound ,Surface conductivity ,chemistry ,Chemical physics ,Surface roughness ,General Materials Science ,[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics ,0210 nano-technology ,Rubrene ,ComputingMilieux_MISCELLANEOUS - Abstract
The relationship between charge transport and surface morphology is investigated by utilizing rubrene single crystals of varying thicknesses. In the case of pristine crystals, the surface conductivities decrease exponentially as the crystal thickness increases until ∼4 μm, beyond which the surface conductivity saturates. Investigation of the surface morphology using optical and atomic force microscopy reveals that thicker crystals have a higher number of molecular steps, increasing the overall surface roughness compared with thin crystals. The density of molecular steps as a surface trap is further quantified with the subthreshold slope of rubrene air-gap transistors. This thickness-dependent surface conductivity is rationalized by a shift from in-plane to out-of-plane transport governed by surface roughness. The surface transport is disrupted by roughening of the crystal surface and becomes limited by the slower vertical crystallographic axis on molecular step edges. Separately, we investigate surface-doping of rubrene crystals by using fluoroalkyltrichrolosilane and observe a different mechanism for charge transport which is independent of surface roughness. This work demonstrates that the correlation between crystal thickness, surface morphology, and charge transport must be taken into account when measuring organic single crystals. Considering the fact that these molecular steps are universally observed on organic/inorganic and single/polycrystals, we believe that our findings can be widely applied to improve charge transport understanding.
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- 2018
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29. Breaking the Bimolecular Crystal: The Effect of Side-Chain Length on Oligothiophene/Fullerene Intercalation
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Detlef-M. Smilgies, Benjamin P. Cherniawski, Stephen J. Rosa, Sean Parkin, Edmund K. Burnett, and Alejandro L. Briseno
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chemistry.chemical_classification ,Fullerene ,Materials science ,General Chemical Engineering ,Dimer ,Intercalation (chemistry) ,02 engineering and technology ,General Chemistry ,Polymer ,Conjugated system ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Branching (polymer chemistry) ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Crystallography ,chemistry ,Materials Chemistry ,Thiophene ,Side chain ,0210 nano-technology - Abstract
Polymer/fullerene bimolecular crystal formation has been investigated using a variety of conjugated polymers and fullerenes to understand the design rules that influence donor–acceptor interaction. Modifications of the polymer by varying the substitution side-chain position, density, and branching have demonstrated the importance of the “pocket” dimensions (free volume between side chains where the fullerene resides) for controlling intercalation. Yet the effect of pocket height has not been systematically explored because of the solubility limitations in polymers. In this report, we present an experimental investigation into the effect of the pocket height by synthesizing poly[2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene] dimers with varied side chain lengths and track the morphological changes of the dimer/fullerene blends using grazing-incidence X-ray scattering, thermal measurements, and photoluminescence quenching. We identify two regimes: (1) oligomers with side chains greater than or equal t...
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- 2018
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30. Oxidation of rubrene, and implications for device stability
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Jack Ly, Hyunbok Lee, Jae Joon Kim, Steven A. Lopez, Kendall N. Houk, Alán Aspuru-Guzik, Janice B. Lin, Edmund K. Burnett, Alejandro L. Briseno, and Lei Zhang
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Chlorinated solvents ,Materials science ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,Mobility devices ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Phenol ,Density functional theory ,Thin film ,0210 nano-technology ,Spectroscopy ,Rubrene ,Single crystal - Abstract
The rapid spontaneous photo-oxidation of rubrene to form endo-peroxide, rubrene-Ox1, was monitored via1H NMR and UV-vis spectroscopy. The reaction is thermally reversible, which restores high mobility devices in both the crystalline thin film and single crystal. Prolonged stirring in chlorinated solvents yields a secondary, irreversible product, rubrene-Ox2, which has lost phenol, as confirmed by single crystal analysis. An acid-catalyzed rearrangement of the endo-peroxide to form rubrene-Ox2 was identified here with Density Functional Theory (DFT). Implications of the nature of these processes for the preparation of organic transistors are described.
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- 2018
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31. A Randomised Evaluation of Low-Dose Cytarabine Arabinoside Plus Lenalidomide Versus Single-Agent Low-Dose Cytarabine Arabinoside in Older Patients with Acute Myeloid Leukaemia: Results from the LI-1 Trial
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Cono Ariti, Alan K. Burnett, Priyanka Mehta, Michael Dennis, Laura Upton, Mhairi Copland, Robert Kerrin Hills, Ian Thomas, N Russell, Shahidul Islam, Mia Sydenham, and Lars Kjeldsen
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Oncology ,medicine.medical_specialty ,business.industry ,Immunology ,Low dose cytarabine ,Cell Biology ,Hematology ,Biochemistry ,Older patients ,Internal medicine ,medicine ,Single agent ,Myeloid leukaemia ,business ,Lenalidomide ,medicine.drug - Abstract
Background: Many patients with Acute Myeloid Leukemia (AML) diagnosed after 60 years of age are not considered suitable for intensive remission induction chemotherapy, either due to co-morbidities or frailty associated with advanced age. Despite treatment with either a hypomethylating agent or low-dose cytarabine arabinoside (LDAC), survival is usually poor, with 1-year survival after LDAC of 24-37% in NCRI AML16 and historical arms of LI-1. Combination therapy with additional agents represents an attractive option, and has the potential to improve patient outcomes without substantially increasing toxicity. Lenalidomide (Revlimid TM) is an immunomodulatory drug, used to treat myeloma, and some cases of myelodysplastic syndrome, and has potent antineoplastic, anti-angiogenic, anti-inflammatory and pro-erythropoietic properties. Early-phase trials of lenalidomide in AML have demonstrated clinical activity with acceptable toxicity. Aim: To assess the efficacy and tolerability of LDAC+lenalidomide versus LDAC alone in patients aged 60+ unsuitable for intensive therapy. The aim was to double 2-year survival from 11% to 22% (HR 0.69). Methods: LI-1 was an international multicentre, multi-arm, randomised phase II trial developed to study the efficacy and tolerability of novel non-intensive therapies in AML using a "pick a winner" design. LDAC was given at 20mg BD SC on days 1-10 of each course. Lenalidomide was administered orally once daily in a flat 10mg dose for 21 days, where day 1 is day 1 of LDAC with courses occurring at 5-week intervals for courses 1-4. Patients considered to be benefitting after 4 courses, i.e. in remission or stable disease, could continue to receive treatment until disease progression, either with LDAC+lenalidomide at 6-week intervals, or lenalidomide only at 4-week intervals if patient had experienced significant toxicity. Toxicities were recorded using CTCAEv3. Primary objectives included overall survival (OS), complete remission (CR + CRi) achievement, reasons for failure, duration of response (CR/CRi), relapse rates and deaths in first CR. Secondary objectives included toxicity, supportive care requirements, and Quality of Life assessments (measured using EORTC QLQ-30, EQ5D and HADS tools). Results: Between Jan-17 and Jun-19, 202 patients from Denmark (8%), New Zealand (16%) and the UK (76%) were randomised. Median age was 78 years (range 62-89). Overall, 58% were male; 76% de novo AML, 20% secondary AML, and 4% high risk MDS; 1% favourable, 66% intermediate, 19% adverse and 14% unknown cytogenetics; WHO performance status 0 for 15%, 1 for 58%, 2 for 22% and 3 for 5%. Median of 2 courses (range 0-24; mean 3.28) was delivered in LDAC arm and 1 course in LDAC+lenalidomide arm (range 0-25; mean 3.48). Overall response (CR/CRi) was achieved in 40/202 patients (20%), (LDAC+lenalidomide 25%, LDAC 14%, OR 0.45 (0.22, 0.93), P=0.031). 30-day mortality was not significantly increased (19% in both arms); and 2-year OS showed no significant difference (14% vs 11.5%, HR 0.94 (0.69, 1.29, P=0.719). Median OS was 3.5 vs 4.6 months; HR 0.96 (0.71, 1.30), P=0.80. 1-year OS for patients that didn't enter CR/CRi was 6.8% for LDAC+lenalidomide vs 16.9% for LDAC (P=0.028). Cause of death for the majority of patients was resistant/recurrent disease: 45(53%) vs 47(58%). Most adverse events (AEs) were grade 1/2 in both arms. During cycle 1, there were 78 vs 51 grade 3/4 AEs in the LDAC+lenalidomide and LDAC arms, respectively (P=0.02). This included 5 thrombotic events in the LDAC+lenalidomide arm (4 grade 3 and 1 grade 4) and none in the LDAC arm. In course 1, supportive care requirements were higher in terms of both days of antibiotics (7 vs 3; p=0.001) and hospitalisation days (11 vs 6.5; p=0.005) for the LDAC+lenalidomide arm. There was no difference in transfusion requirements. Conclusions: Despite improving the CR/CRi rate, the combination of lenalidomide+LDAC did not improve OS, relapse-free survival or time in remission in elderly patients with AML. The addition of lenalidomide to LDAC resulted in increased toxicity, including episodes of thrombosis, as well as increased supportive care requirements. Alternative strategies to improve survival for elderly patients with AML remain a significant clinical need. Acknowledgements: We are grateful to Blood Cancer UK for funding the trial and Celgene for providing drug and additional support for this IIS. Fig 1: OS All patients Figure 1 Figure 1. Disclosures Copland: Astellas: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Incyte: Honoraria, Research Funding, Speakers Bureau; Jazz: Honoraria, Speakers Bureau; Cyclacel Ltd: Research Funding. Russell: Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Speakers Bureau; Astellas: Membership on an entity's Board of Directors or advisory committees; Jazz: Research Funding, Speakers Bureau. OffLabel Disclosure: Off label use of lenalidomide in combination with low dose cytarabine will be discussed in the setting of elderly unfit AML.
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- 2021
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32. A Randomised Evaluation of Low-Dose Ara-C Plus BCT-100 Versus Low Dose Ara-C in Older Patients with Acute Myeloid Leukaemia: Results from the LI-1 Trial
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Mary Frances McMullin, Ian Thomas, Priyanka Mehta, Francis Mussai, Nigel H. Russell, Cono Ariti, Laura Upton, Mhairi Copland, Robert Kerrin Hills, Steve Knapper, Alan K. Burnett, and Mia Sydenham
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medicine.medical_specialty ,business.industry ,Immunology ,Low dose ,Cell Biology ,Hematology ,Biochemistry ,Gastroenterology ,Older patients ,Internal medicine ,medicine ,Myeloid leukaemia ,business ,health care economics and organizations - Abstract
Background: Among patients with Acute Myeloid Leukaemia (AML) over the age of 60, a considerable number are not considered suitable for intensive remission-induction chemotherapy. Survival in these patients is poor, whether they are treated using hypomethylating agents or low-dose ara-C (LDAC). The possibility of combination therapy with additional agents represents an attractive option. Arginine metabolism plays a key role in AML pathogenesis (Mussai et al. Blood 2013); BCT-100 is a pegylated recombinant human arginase that leads to a rapid depletion in extracellular and intracellular arginine concentrations resulting in G0/G1 arrest, and subsequent death by necrosis. BCT-100 demonstrates significant activity as single-agent against AML cell lines, AML xenografts and primary AML blasts from newly diagnosed or relapsed patients (Mussai et al. Blood 2015). Importantly BCT-100 is synergistic in combination with cytarabine. Aims: To assess the efficacy of LDAC+BCT100 versus LDAC alone in patients aged 60+ unsuitable for intensive therapy, in a "pick a winner" design. This design allows several treatments to be assessed simultaneously in a randomised fashion, with the aim of doubling 2-year survival from 11% to 22% (HR 0.69), with interim assessments after 50 and 100 patients per arm are recruited. Methods: LDAC was given at 20mg BD SC on days 1-10 of each course. Patients randomised to the combination received LDAC as above with BCT-100 1600U/kg on Days 1, 8, 15 and 22 as a 1-hour intravenous infusion. Courses occurred at 4-6 week intervals. Toxicities were recorded using CTCAE version 3. Pharmacokinetic and biomarker samples were assessed in BCT-100 patients. Results here are based upon median follow-up of 3.8 months (range: 0.1 - 20.6 months) Results: Between September 2018 and December 2020, 83 patients were randomised. The trial was prematurely closed due to the COVID pandemic and did not reach the pre-planned first evaluation. Median age was 76.7 years (range 62-88). Overall, 65% were male; 70% de novo AML, 23% secondary AML, and 6% high risk MDS; 2% favourable, 59% intermediate, 23% adverse and 15% unknown/unreported cytogenetics. Median of 2 courses was delivered in either arm (mean 2 LDAC, 2 LDAC+BCT, range for both: 1-12). BCT-100 leads to a depletion of arginine from baseline in the majority of patients. Overall response (CR/CRi) was achieved in 12/81 patients (15%), (LDAC+BCT-100 15%, LDAC 15%, R 1.03 (0.30, 3.51),P=0.963). Thirty-day mortality was not significantly increased (18% vs 11%, HR 1.71 (0.50, 5.84), P=0.393; and 1-year survival showed no evidence of a difference (31% vs 30%, HR 1.28 (0.72, 2.25). Median overall survival time was 3.8 vs 6.4months; overall survival HR 1.11 (0.64, 1.90), P=0.715. The most common cause of death was resistant/recurrent disease: 12(46%) vs 16(59%). BCT-100 was not associated with any haematological toxicity; although rare grade 3/4 cardiac and hepatic events were reported, these were not significantly increased with BCT-100. Summary: The addition of BCT-100 to LDAC did not improve response rate or survival. BCT-100 was well tolerated with an acceptable toxicity profile. Further clinical evaluation of BCT-100 induced arginase depletion continues in a variety of malignancies. Acknowledgements: We are grateful to Blood Cancer UK for funding the trial and Bio-Cancer Treatment International for providing drug and additional support for this Investigator Initiated Study. Figure 1. OS All patients Figure 1 Figure 1. Disclosures Knapper: Jazz: Consultancy, Speakers Bureau; Pfizer: Consultancy, Speakers Bureau; Astellas: Ended employment in the past 24 months, Speakers Bureau; Novartis: Consultancy, Research Funding, Speakers Bureau. McMullin: Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Other: clinical trial support, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AOP Orphan: Research Funding, Speakers Bureau. Copland: Incyte: Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; Cyclacel Ltd: Research Funding; Astellas: Honoraria, Speakers Bureau; Jazz: Honoraria, Speakers Bureau. Russell: Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Speakers Bureau; Astellas: Membership on an entity's Board of Directors or advisory committees; Jazz: Research Funding, Speakers Bureau.
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- 2021
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33. Prediction of Early Mortality with Non-Intensive Acute Myeloid Leukemia (AML) Therapies: Analysis of 1336 Patients from MRC/NCRI and SWOG
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Cono Ariti, Harry P. Erba, Mia Sydenham, Sucha Nand, Alan K. Burnett, Megan Othus, Kathleen F. Kerr, Ian Thomas, Laura C. Michaelis, Michael Dennis, Xu Wang, Roland B. Walter, Sarit Assouline, Priyanka Mehta, Nigel H Russel, and Robert Kerrin Hills
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Oncology ,medicine.medical_specialty ,business.industry ,Internal medicine ,Immunology ,Medicine ,Myeloid leukemia ,Cell Biology ,Hematology ,business ,Biochemistry - Abstract
Background: Therapeutic resistance and treatment tolerance vary greatly in patients with AML, likely due to the advanced age and genetic diversity in pharmacokinetics of those affected. Undoubtedly, tools to accurately predict outcomes of individual therapies for patients could inform decision-making and improve response rates. To this end, several scoring systems have been developed aimed at identifying patients at high risk of poor outcome after intensive chemotherapy. Similar tools for use after non-intensive therapies are currently not available. As such therapies are increasingly effective and more widely utilized we sought to develop tools to predict early death and survival for patients treated with non-intensive therapies. Patients and Methods: We developed prediction models for all-cause death by day 28, 42, 56, and 100 from enrollment using data from 796 patients enrolled on MRC/NCRI trial LI-1, which we then validated in a cohort of 540 patients treated on SWOG trials S0432, S0703, and S1612. Treatments included: Low dose Ara-C (LDAC) alone, sapacitabine alone and LDAC in combination with vosaroxin, tosedostat or ganetespib (MRC/NCRI); Azacytidine (AZA) alone, tipifarnib alone, and AZA in combination with mylotarg, midostaurin, and nivolumab (SWOG). The following covariates were available in the MRC/NCRI and SWOG cohorts to build multivariable logistic regression models (quantitative unless specified otherwise): age, performance status (PS; 0-1 vs. 2-4), secondary AML (vs. de novo AML or high-risk myelodysplastic syndrome), white blood cell and platelet counts, and percentage of bone marrow blasts - all assessed at enrollment. The regression coefficients from the model fit in the MRC/NCRI cohort were used to derive a score and applied to each patient in the SWOG cohort. The models' prognostic accuracies were assessed using the area under the receiver operating characteristic curve (AUC). For the MRC/NCRI cohort, additional covariates were available: cytogenetic risk (per Grimwade 2011), FLT3-ITD, and NPM1 mutation and patient-reported outcomes using the QLQ-C30 instrument. Logistic regression models with these covariates were fit and optimism-corrected AUC estimated to assess prognostic performance for early death. Results: Both patient cohorts were largely composed of older individuals (median age of 75 [range: 60-91] for MRC/NCRI and 77 [60-94] for SWOG, respectively. A substantial subset in each had a PS of 2-4 (MRC/NCRI: 20%; SWOG: 37%) and/or secondary AML (MRC/NCRI: 26%; SWOG: 41%). Overall, the ability to predict early death either by day 28, 42, 56, or 100 was limited in the MRC/NCRI cohort. Subscales of the QLQ-C30 had univariate AUC=0.67, the highest among all covariates evaluated. Multivariable models with just clinical covariates had optimism-corrected AUCs ranging from 0.63-0.65; adding cytogenetic risk and FLT3-ITD and NPM1 mutation status led optimism-corrected AUCs ranging from 0.64-0.66; addition of two QLQ-C30 subscales (fatigue and appetite loss) led to optimism-corrected AUCs ranging from 0.66-0.69. The SWOG cohort did not collect QLQ-C30 or mutational data on all patients and only the clinical multivariable models could be evaluated. The models had a similar performance in the SWOG cohort with AUCs ranging from 0.65-0.68. Conclusion: Our ability to predict early death in older patients treated with lower intensity AML therapies is limited with routinely available clinical variables. Inclusion of cytogenetic risk, FLT3-ITD, and NPM1 mutation status minimally improved the prognostic accuracy as did some of the QLQ-C30 subscales. Our data highlight the difficulties in predicting outcomes with non-intensive AML therapy with routinely available baseline clinical information. Improving the clinical utility of these models may require more complete characterization of patient comorbidities (including frailty index, cognitive function, renal and hepatic function, comorbidity scores) or additional PRO measures since some QLQ-C30 subscales had the strongest univariate signals. Support: NIH/NCI grants CA180888 and CA180819; Blood Cancer UK grant 13041 and Cardiff University. Figure 1 Figure 1. Disclosures Assouline: Novartis: Honoraria, Research Funding; Amgen: Current equity holder in publicly-traded company, Research Funding; Gilead: Speakers Bureau; Johnson&Johnson: Current equity holder in publicly-traded company; Jewish General Hospital, Montreal, Quebec: Current Employment; Eli Lilly: Research Funding; Roche/Genentech: Research Funding; Takeda: Research Funding; BeiGene: Consultancy, Honoraria, Research Funding; F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Research Funding; AstraZeneca: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria. Erba: AbbVie Inc; Agios Pharmaceuticals Inc; Astellas; Bristol Myers Squibb; Celgene, a Bristol Myers Squibb company; Daiichi Sankyo Inc; Genentech, a member of the Roche Group; GlycoMimetics Inc; Incyte Corporation; Jazz Pharmaceuticals Inc; Kura Oncology; Nov: Other: Advisory Committee; AbbVie Inc: Other: Independent review committee; AbbVie Inc; Agios Pharmaceuticals Inc; Bristol Myers Squibb; Celgene, a Bristol Myers Squibb company; Incyte Corporation; Jazz Pharmaceuticals Inc; Novartis: Speakers Bureau; AbbVie Inc; Agios Pharmaceuticals Inc; ALX Oncology; Amgen Inc; Daiichi Sankyo Inc; FORMA Therapeutics; Forty Seven Inc; Gilead Sciences Inc; GlycoMimetics Inc; ImmunoGen Inc; Jazz Pharmaceuticals Inc; MacroGenics Inc; Novartis; PTC Therapeutics: Research Funding. Walter: Jazz: Research Funding; Pfizer: Consultancy, Research Funding; Selvita: Research Funding; Amphivena: Consultancy, Other: ownership interests; Agios: Consultancy; Astellas: Consultancy; BMS: Consultancy; Genentech: Consultancy; Janssen: Consultancy; Kite: Consultancy; Macrogenics: Consultancy, Research Funding; Immunogen: Research Funding; Celgene: Consultancy, Research Funding; Aptevo: Consultancy, Research Funding; Amgen: Research Funding. Othus: Daiichi Sankyo: Consultancy; Celgene: Other: Data safety monitoring board; Merck: Consultancy; Biosight: Consultancy; Glycomimetics: Other: Data safety monitoring board.
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- 2021
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34. A randomized assessment of adding the kinase inhibitor lestaurtinib to first-line chemotherapy for FLT3-mutated AML
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Robert Kerrin Hills, Amanda F. Gilkes, James D. Cavenagh, Nigel H. Russell, Mark J. Levis, Lars Kjeldsen, Rosemary E. Gale, Gail Jones, Heiko Konig, Michael R. Grunwald, Steven Knapper, Alan K. Burnett, and Ian Thomas
- Subjects
0301 basic medicine ,Oncology ,Male ,Clinical Trials and Observations ,Kaplan-Meier Estimate ,Pharmacology ,Biochemistry ,0302 clinical medicine ,hemic and lymphatic diseases ,Antineoplastic Combined Chemotherapy Protocols ,Medicine ,Child ,Lestaurtinib ,Hazard ratio ,Hematopoietic Stem Cell Transplantation ,Hematology ,Induction Chemotherapy ,Middle Aged ,Chemotherapy regimen ,Leukemia, Myeloid, Acute ,030220 oncology & carcinogenesis ,Child, Preschool ,Female ,medicine.drug ,Adult ,medicine.medical_specialty ,Adolescent ,Gemtuzumab ozogamicin ,Immunology ,Carbazoles ,Disease-Free Survival ,03 medical and health sciences ,Young Adult ,Internal medicine ,Humans ,Furans ,Protein Kinase Inhibitors ,Aged ,Proportional Hazards Models ,business.industry ,Surrogate endpoint ,Induction chemotherapy ,Consolidation Chemotherapy ,Cell Biology ,030104 developmental biology ,fms-Like Tyrosine Kinase 3 ,Fms-Like Tyrosine Kinase 3 ,Mutation ,business - Abstract
The clinical benefit of adding FMS-like tyrosine kinase-3 (FLT3)-directed small molecule therapy to standard first-line treatment of acute myeloid leukemia (AML) has not yet been established. As part of the UK AML15 and AML17 trials, patients with previously untreated AML and confirmed FLT3-activating mutations, mostly younger than 60 years, were randomly assigned either to receive oral lestaurtinib (CEP701) or not after each of 4 cycles of induction and consolidation chemotherapy. Lestaurtinib was commenced 2 days after completing chemotherapy and administered in cycles of up to 28 days. The trials ran consecutively. Primary endpoints were overall survival in AML15 and relapse-free survival in AML17; outcome data were meta-analyzed. Five hundred patients were randomly assigned between lestaurtinib and control: 74% had FLT3-internal tandem duplication mutations, 23% FLT3-tyrosine kinase domain point mutations, and 2% both types. No significant differences were seen in either 5-year overall survival (lestaurtinib 46% vs control 45%; hazard ratio, 0.90; 95% CI 0.70-1.15; P = .3) or 5-year relapse-free survival (40% vs 36%; hazard ratio, 0.88; 95% CI 0.69-1.12; P = .3). Exploratory subgroup analysis suggested survival benefit with lestaurtinib in patients receiving concomitant azole antifungal prophylaxis and gemtuzumab ozogamicin with the first course of chemotherapy. Correlative studies included analysis of in vivo FLT3 inhibition by plasma inhibitory activity assay and indicated improved overall survival and significantly reduced rates of relapse in lestaurtinib-treated patients who achieved sustained greater than 85% FLT3 inhibition. In conclusion, combining lestaurtinib with intensive chemotherapy proved feasible in younger patients with newly diagnosed FLT3-mutated AML, but yielded no overall clinical benefit. The improved clinical outcomes seen in patients achieving sustained FLT3 inhibition encourage continued evaluation of FLT3-directed therapy alongside front-line AML treatment. The UK AML15 and AML17 trials are registered at www.isrctn.com/ISRCTN17161961 and www.isrctn.com/ISRCTN55675535 respectively.
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- 2019
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35. The effect of hexyl side chains on molecular conformations, crystal packing, and charge transport of oligothiophenes
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Steven A. Lopez, Kendall N. Houk, Ilhan Yavuz, Sean Parkin, Lei Zhang, Alejandro L. Briseno, Edmund K. Burnett, and Benjamin P. Cherniawski
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chemistry.chemical_classification ,Chemistry ,Stereochemistry ,Dimer ,Substituent ,02 engineering and technology ,General Chemistry ,Crystal structure ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Crystallography ,Monomer ,Alkane stereochemistry ,Materials Chemistry ,Side chain ,Molecule ,0210 nano-technology ,Alkyl - Abstract
We report substituent effects on conformational preferences and hole mobilities of 2,5-bis-(thiophen-2-yl)thieno[3,2-b]thiophenes (BTTT) monomer and dimer, and hexyl derivatives. We employ single-crystal X-ray diffraction, quantum mechanical calculations, and thin-film transistors to explore the difference between monomer, dimer, and effect of hexyl substitution. The hexyl-substituted molecules show marked differences in solid-state packing compared to the unsubstituted analogs. Most notably, the alkylated monomer crystal structure exhibits terminal thiophenes in the syn conformation. In contrast, the unsubstituted monomer adopts the more common anti conformation. The hexyl-substituted dimer, however, features a mixture of syn and anti thiophenes. Gas phase conformations of oligomers rationalize the intrinsic conformational preferences. We use a multimode simulation to compute hole mobilities and find excellent agreement with experiment. Theoretical results support our hypothesis that alkyl side chains cause these small molecules to adopt orientations that enhance hole mobilities by an order of magnitude upon hexyl substitution of the monomer.
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- 2017
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36. Pinaceous Wood from the Lower Cretaceous (Barremian—Early Aptian) of California, USA; Lower Chickabally Member, Budden Canyon Formation
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Emma R. Fryer, Alexandru M. F. Tomescu, Christa R. Unger, and Jamie K. Burnett
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Canyon ,010506 paleontology ,geography ,geography.geographical_feature_category ,biology ,Aptian ,Paleontology ,010502 geochemistry & geophysics ,biology.organism_classification ,01 natural sciences ,Cretaceous ,chemistry.chemical_compound ,chemistry ,Pinaceae ,Tracheid ,Fossil wood ,Carbonate ,Ecology, Evolution, Behavior and Systematics ,Geology ,0105 earth and related environmental sciences - Abstract
The Budden Canyon Formation is a Cretaceous unit spanning the Valanginian—Turonian interval in northern California. This marine unit includes plant-fossiliferous near-shore sequences, with richest plant fossil occurrences in the Hauterivian—Aptian. The Lower Chickabally Member (Barremian—early Aptian, ca. 125 Ma) hosts a rich flora preserved anatomically in carbonate concretions, near the town of Ono. The material is dominated by conifers: wood, foliage, cones and dispersed seeds. We characterize the anatomy of a coniferous trunk. The wood exhibits axial and radial resin canals with thick-walled epithelial cells, distinct growth rings, and conspicuous early to late wood transition. Axial tracheids bear radial uniseriate and opposite biseriate pitting. Rays are uniseriate with biseriate portions, with scarce ray tracheids and taxodioid cross-field pitting. Traumatic resin canals form extensive tangential bands. The axial and radial resin canals indicate pinaceous affinities for the Ono wood, but s...
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- 2016
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37. Graphene Ink as a Conductive Templating Interlayer for Enhanced Charge Transport of C60-Based Devices
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Alejandro L. Briseno, Hyunbok Lee, Ethan B. Secor, James J. Watkins, D. Leonardo Gonzalez Arellano, Edmund K. Burnett, and Mark C. Hersam
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Materials science ,business.industry ,Graphene ,Graphene foam ,Nanotechnology ,02 engineering and technology ,Substrate (electronics) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,Semiconductor ,law ,Optoelectronics ,General Materials Science ,Thin film ,0210 nano-technology ,business ,Bilayer graphene ,Graphene nanoribbons ,Graphene oxide paper - Abstract
We demonstrate conductive templating interlayers of graphene ink, integrating the electronic and chemical properties of graphene in a solution-based process relevant for scalable manufacturing. Thin films of graphene ink are coated onto ITO, following thermal annealing, to form a percolating network used as interlayer. We employ a benchmark n-type semiconductor, C60, to study the interface of the active layer/interlayer. On bare ITO, C60 molecules form films of homogeneously distributed grains; with a graphene interlayer, a preferential orientation of C60 molecules is observed in the individual graphene plates. This leads to crystal growth favoring enhanced charge transport. We fabricate devices to characterize the electron injection and the effect of graphene on the device performance. We observe a significant increase in the current density with the interlayer. Current densities as high as ∼1 mA/cm2 and ∼70 mA/cm2 are realized for C60 deposited with the substrate at 25 °C and 150 °C, respectively.
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- 2016
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38. Lack of glucuronidation products of trans-resveratrol in plasma and urine of cats
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Andrea J. Fascetti, Jon J. Ramsey, Birgit Puschner, K. Burnett, Alfreda Wei, and Yanping Lin
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Male ,0301 basic medicine ,medicine.medical_specialty ,endocrine system diseases ,Glucuronidation ,Urine ,Resveratrol ,030226 pharmacology & pharmacy ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Food Animals ,Oral administration ,Internal medicine ,Stilbenes ,Blood plasma ,medicine ,Animals ,CATS ,Trans-resveratrol ,organic chemicals ,food and beverages ,Animal Feed ,Diet ,Specific Pathogen-Free Organisms ,030104 developmental biology ,Endocrinology ,chemistry ,Cats ,Animal Nutritional Physiological Phenomena ,Female ,Animal Science and Zoology ,Glucuronide - Abstract
Author(s): Burnett, K; Puschner, B; Ramsey, JJ; Lin, Y; Wei, A; Fascetti, AJ | Abstract: Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH Resveratrol has generated interest in cats due to reported health benefits. Cats have low activity of β-glucuronidase, and we hypothesized they could not form two common resveratrol metabolites, resveratrol-3-O-glucuronide and resveratrol-4′-O-glucuronide. Resveratrol, 3 mg/cat/day, was given orally to intact male (n = 5) and female cats (n = 5) for 4 weeks. A control group (8 intact males) was used for comparison. Plasma and urine were collected weekly and analysed using high-pressure liquid chromatography coupled with tandem mass spectrometry. Resveratrol and resveratrol-3-O-sulphate, but no glucuronide metabolites, were detected in plasma and urine. Median (range 10–90th percentile) plasma resveratrol for control and treatment groups was 0.46 ng/ml (0.02–1.74 ng/ml) and 0.96 ng/ml (0.65–3.21 ng/ml). Median (range) plasma resveratrol-3-O-sulphate for control and treatment groups was 6.32 ng/ml (2.55–10.29 ng/ml) and 11.45 ng/ml (1.47–53.29 ng/ml). Plasma resveratrol differed from control in week 4, while plasma resveratrol-3-O-sulphate was different in all weeks (p l 0.05). Median (range) urine resveratrol for control and treatment groups was 0.28 ng/ml (0.05–1.59 ng/ml) and 19.98 ng/ml (8.44–87.54 ng/ml). Median (range) urine resveratrol-3-O-sulphate for control and treatment groups was 26.71 ng/ml (10.50–75.58 ng/ml) and 108.69 ng/ml (11.83–231.05 ng/ml). All time points for urine resveratrol and resveratrol-3-O-sulphate were significantly different from control (p l 0.05), except for weeks 1, 3 and 4 for resveratrol. The results support our hypothesis that cats are unlikely able to glucuronidate resveratrol, most likely due to a reduction in the activity of β-glucuronidase.
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- 2016
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39. Germination patterns in three terrestrial orchids relate to abundance of mycorrhizal fungi
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Melissa K. McCormick, D. Lee Taylor, Dennis F. Whigham, and Robert K. Burnett
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0106 biological sciences ,education.field_of_study ,Goodyera pubescens ,Orchidaceae ,Ecology ,biology ,Host (biology) ,fungi ,Population ,Tulasnella ,Plant Science ,Tipularia discolor ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Germination ,Abundance (ecology) ,Botany ,education ,Ecology, Evolution, Behavior and Systematics ,010606 plant biology & botany - Abstract
Summary The spatial distribution of plants, which is often generated by patterns of seed recruitment, is an important determinant of population dynamics, especially for orchids with seeds that must be exposed to appropriate mycorrhizal fungi. We compared the distribution and abundance of target mycorrhizal fungi detected in the soil using DNA-based molecular techniques and germination in seed packets of Goodyera pubescens, Liparis liliifolia and Tipularia discolor. We further examined Tulasnella spp. associated with G. pubescens to determine whether areas with abundant host fungi resulted from multiple genets of the same species or from a single widespread fungal genet. We found that target fungi were more likely to be detected using soil DNA assays than by seed germination. Based on soil DNA, fungi were more widespread than suggested by seed germination, which most often reflected the presence of abundant mycorrhizal fungi in the soil. Fungi were more likely to be abundant close to established orchids. Established plants of G. pubescens that were 50 cm apart associated with multiple fungal genets. Synthesis. This study demonstrates the importance of using multiple methods to detect the distribution and abundance of target fungi and suggests that fungal ‘hot spots’ may be keys to the dynamics of orchid populations.
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- 2016
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40. Stress, burnout, depression and work satisfaction among <scp>UK</scp> anaesthetic trainees – a response
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T. Heaton, M. Devlin, T. Hardern, and K. Burnett
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Depression ,business.industry ,MEDLINE ,Personal Satisfaction ,Burnout, Psychological ,Burnout ,Job Satisfaction ,United Kingdom ,Anesthesiology and Pain Medicine ,Stress (linguistics) ,Humans ,Medicine ,Job satisfaction ,business ,Stress, Psychological ,Depression (differential diagnoses) ,Anesthetics ,Clinical psychology - Published
- 2020
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41. Enhanced Device Efficiency and Long-Term Stability via Boronic Acid-Based Self-Assembled Monolayer Modification of Indium Tin Oxide in a Planar Perovskite Solar Cell
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D. Leonardo Gonzalez Arellano, Duygu Akın Kara, Edmund K. Burnett, Koray Kara, Sumeyra Buyukcelebi, Gorkem Oylumluoglu, Alejandro L. Briseno, Faruk Ozel, Jae Joon Kim, Mesude Zeliha Yigit, Mahmut Kus, Özlem Usluer, and Mustafa Can
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Materials science ,Passivation ,Perovskite solar cell ,Self-assembled monolayer ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Indium tin oxide ,law.invention ,Chemical engineering ,law ,Monolayer ,Solar cell ,Surface modification ,General Materials Science ,0210 nano-technology ,Perovskite (structure) - Abstract
Interfacial engineering is essential for the development of highly efficient and stable solar cells through minimizing energetic losses at interfaces. Self-assembled monolayers (SAMs) have been shown as a handle to tune the work function (WF) of indium tin oxide (ITO), improving photovoltaic cell performance and device stability. In this study, we utilize a new class of boronic acid-based fluorine-terminated SAMs to modify ITO surfaces in planar perovskite solar cells. The SAM treatment demonstrates an increase of the WF of ITO, an enhancement of the short-circuit current, and a passivation of trap states at the ITO/[poly(3,4ethylenedioxylenethiophene):poly(styrenesulfonic acid)] interface. Device stability improves upon SAM modification, with efficiency decreasing only 20% after one month. Our work highlights a simple treatment route to achieve hysteresis-free, reproducible, stable, and highly efficient (16%) planar perovskite solar cells.
- Published
- 2018
42. Gecko-Inspired Biocidal Organic Nanocrystals Initiated from a Pencil-Drawn Graphite Template
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Feyza Dundar Arisoy, Jessica D. Schiffman, David Leonardo Gonzalez Arellano, Irene S. Kurtz, Edmund K. Burnett, Alejandro L. Briseno, Kristopher W. Kolewe, Victor K. Champagne, and Julia A. Zakashansky
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Indoles ,Nanostructure ,Materials science ,Silicon ,lcsh:Medicine ,chemistry.chemical_element ,02 engineering and technology ,Isoindoles ,010402 general chemistry ,01 natural sciences ,Article ,Escherichia coli ,Organometallic Compounds ,Animals ,Gecko ,Graphite ,Polyimide foil ,lcsh:Science ,Nanopillar ,Zinc phthalocyanine ,Multidisciplinary ,biology ,lcsh:R ,Lizards ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Anti-Bacterial Agents ,0104 chemical sciences ,chemistry ,Nanocrystal ,Chemical engineering ,Zinc Compounds ,Nanoparticles ,lcsh:Q ,0210 nano-technology - Abstract
The biocidal properties of gecko skin and cicada wings have inspired the synthesis of synthetic surfaces decorated with high aspect ratio nanostructures that inactivate microorganisms. Here, we investigate the bactericidal activity of oriented zinc phthalocyanine (ZnPc) nanopillars grown using a simple pencil-drawn graphite templating technique. By varying the evaporation time, nanopillars initiated from graphite that was scribbled using a pencil onto silicon substrates were optimized to yield a high inactivation of the Gram-negative bacteria, Escherichia coli. We next adapted the procedure so that analogous nanopillars could be grown from pencil-drawn graphite scribbled onto stainless steel, flexible polyimide foil, and glass substrates. Time-dependent bacterial cytotoxicity studies indicate that the oriented nanopillars grown on all four substrates inactivated up to 97% of the E. coli quickly, in 15 min or less. These results suggest that organic nanostructures, which can be easily grown on a broad range of substrates hold potential as a new class of biocidal surfaces that kill microbes quickly and potentially, without spreading antibiotic-resistance genes.
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- 2018
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43. Phase Transition of Graphene-Templated Vertical Zinc Phthalocyanine Nanopillars
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D. Leonardo Gonzalez Arellano, Alejandro L. Briseno, Stefan C. B. Mannsfeld, Julia A. Zakashansky, Michelle H George, Sema Demirci Uzun, Edmund K. Burnett, and Victor K. Champagne
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Chemiresistor ,Phase transition ,Chemistry ,Graphene ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,Catalysis ,0104 chemical sciences ,law.invention ,Crystal ,Colloid and Surface Chemistry ,Chemical engineering ,law ,Phase (matter) ,Crystallization ,0210 nano-technology ,Single crystal ,Nanopillar - Abstract
We report on the graphene-assisted growth, crystallization, and phase transition of zinc phthalocyanine (ZnPc) vertically oriented single crystal nanopillars. Postcrystallization thermal annealing of the nanostructures results in a molecular packing change while maintaining the vertical orientation of the single crystals orthogonal to the underlying substrate. Grazing incidence X-ray diffraction and high-resolution TEM studies characterized this phase transition from a metastable crystal phase to the more stable β-phase commonly observed in bulk crystals. These vertical arrays of crystalline nanopillars exhibit a high-surface-to-volume ratio, which is advantageous for applications such as gas sensors. We fabricated chemiresistor sensors with ZnPc nanopillars grown on graphene and demonstrated its selectivity for ammonia vapors, and improvement in sensitivity in the β-phase crystal packing pillars due to their molecular orientation increasing the exposure of the Zn2+ ion to the ammonia analyte. This work h...
- Published
- 2018
44. A comparison of FLAG-Ida and daunorubicin combined with clofarabine in high-risk acute myeloid leukaemia: data from the UK NCRI AML17 Trial
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A. Ali, Ove Juul Nielsen, Ian Thomas, Ann Hunter, Sylvie D. Freeman, Nigel H. Russell, Alan K. Burnett, Robert Kerrin Hills, and P Cahalin
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0301 basic medicine ,Oncology ,Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Myeloid ,Adolescent ,Daunorubicin ,Brief Communication ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,Granulocyte Colony-Stimulating Factor ,medicine ,Clofarabine ,Humans ,business.industry ,Cytarabine ,Hematology ,Middle Aged ,medicine.disease ,United Kingdom ,Leukemia ,Leukemia, Myeloid, Acute ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,FLAG (chemotherapy) ,Female ,Myeloid leukaemia ,business ,Idarubicin ,Vidarabine ,medicine.drug - Published
- 2018
45. Preclinical toxicity evaluation of a novel immunotoxin, D2C7-(scdsFv)-PE38KDEL, administered via intracerebral convection-enhanced delivery in rats
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Ramona M. Rodriguiz, Xuhui Bao, Darell D. Bigner, Chien-Tsun Kuan, Vidyalakshmi Chandramohan, John N. Norton, Edward D. Levin, Bruce K. Burnett, Dipendra K. Aryal, Roger E. McLendon, Neil A. Petry, William C. Wetsel, Randall P. Reynolds, Ira Pastan, Michael R. Zalutsky, Supporting clinical sciences, and Medical Imaging
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Male ,medicine.medical_specialty ,Immunoconjugates ,Drug Evaluation, Preclinical ,Pharmacology ,Convection ,Article ,Rats, Sprague-Dawley ,Inhibitory Concentration 50 ,03 medical and health sciences ,Drug Delivery Systems ,0302 clinical medicine ,Immunotoxin ,Edema ,medicine ,Animals ,Pharmacology (medical) ,Encephalomalacia ,Injections, Intraventricular ,Gross Pathologic Examination ,business.industry ,Immunotoxins ,Brain ,Clinical trial ,Oncology ,030220 oncology & carcinogenesis ,Cohort ,Toxicity ,Female ,Histopathology ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Single-Chain Antibodies - Abstract
D2C7-(scdsFv)-PE38KDEL (D2C7-IT) is a novel immunotoxin that reacts with wild-type epidermal growth factor receptor (EGFRwt) and mutant EGFRvIII proteins overexpressed in glioblastomas. This study assessed the toxicity of intracerebral administration of D2C7-IT to support an initial Food and Drug Administration Investigational New Drug application. After the optimization of the formulation and administration, two cohorts (an acute and chronic cohort necropsied on study days 5 and 34) of Sprague-Dawley (SD) rats (four groups of 5 males and 5 females) were infused with the D2C7-IT formulation at total doses of 0, 0.05, 0.1, 0.4 µg (the acute cohort) and 0, 0.05, 0.1, 0.35 µg (the chronic cohort) for approximately 72 hours by intracerebral convection-enhanced delivery using osmotic pumps. Mortality was observed in the 0.40 µg (5/10 rats) and 0.35 µg (4/10 rats) high-dose groups of each cohort. Body weight loss and abnormal behavior were only revealed in the rats treated with high doses of D2C7-IT. No dose-related effects were observed in clinical laboratory tests in either cohort. A gross pathologic examination of systemic tissues from the high-dose and control groups in both cohorts exhibited no dose-related or drug-related pathologic findings. Brain histopathology revealed the frequent occurrence of dose-related encephalomalacia, edema, and demyelination in the high-dose groups of both cohorts. In this study, the maximum tolerated dose of D2C7-IT was determined to be between 0.10 and 0.35 µg, and the no observed adverse effect level was 0.05 µg in SD rats. Both parameters were utilized to design the Phase I/II D2C7-IT clinical trial.
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- 2016
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46. Characteristics and outcome of patients with therapy-related acute promyelocytic leukemia front-line treated with or without arsenic trioxide
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Richard F. Schlenk, David Grimwade, E. Estey, Martin Görner, Mark J. Levis, Zdeněk Ráčil, Tomáš Szotkowski, Sabine Kayser, Axel Benner, Jiří Mayer, Christian Thiede, Uwe Platzbecker, B D Smith, Maria R. Baer, Joerg Westermann, Jan Novák, Patrick K. Gonzales, Martin S. Tallman, Michelle A. Elliott, Kelly J. Norsworthy, Nigel H. Russell, Alwin Krämer, Roland B. Walter, Pavel Žák, Christoph Röllig, Anthony D. Ho, Robert Kerrin Hills, G. Ehninger, A. K. Burnett, and Julia Krzykalla
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Acute promyelocytic leukemia ,Adult ,Male ,Cancer Research ,Pathology ,medicine.medical_specialty ,Adolescent ,Malignancy ,Gastroenterology ,Article ,Arsenicals ,03 medical and health sciences ,chemistry.chemical_compound ,Young Adult ,0302 clinical medicine ,Arsenic Trioxide ,Leukemia, Promyelocytic, Acute ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Humans ,Arsenic trioxide ,neoplasms ,Survival analysis ,Aged ,Aged, 80 and over ,Hematology ,business.industry ,organic chemicals ,Remission Induction ,Myeloid leukemia ,Neoplasms, Second Primary ,Oxides ,Middle Aged ,medicine.disease ,Survival Analysis ,biological factors ,3. Good health ,Lymphoma ,Leukemia ,Treatment Outcome ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Female ,business ,030215 immunology - Abstract
Therapy-related acute promyelocytic leukemia (t-APL) is relatively rare, with limited data on outcome after treatment with arsenic trioxide (ATO) compared to standard intensive chemotherapy (CTX). We evaluated 103 adult t-APL patients undergoing treatment with all-trans retinoic acid (ATRA) alone (n = 7) or in combination with ATO (n = 24), CTX (n = 53), or both (n = 19). Complete remissions were achieved after induction therapy in 57% with ATRA, 100% with ATO/ATRA, 78% with CTX/ATRA, and 95% with CTX/ATO/ATRA. Early death rates were 43% for ATRA, 0% for ATO/ATRA, 12% for CTX/ATRA and 5% for CTX/ATO/ATRA. Three patients relapsed, two developed therapy-related acute myeloid leukemia and 13 died in remission including seven patients with recurrence of the prior malignancy. Median follow-up for survival was 3.7 years. None of the patients treated with ATRA alone survived beyond one year. Event-free survival was significantly higher after ATO-based therapy (95%, 95% CI, 82–99%) as compared to CTX/ATRA (78%, 95% CI, 64–87%; P= 0.042), if deaths due to recurrence of the prior malignancy were censored. The estimated 2-year overall survival in intensively treated patients was 88% (95% CI, 80–93%) without difference according to treatment (P= 0.47). ATO when added to ATRA or CTX/ATRA is feasible and leads to better outcomes as compared to CTX/ATRA in t-APL.
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- 2017
47. ClinicalTrials.gov Reporting: Strategies for Success at an Academic Health Center
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Erin K. O'Reilly, Amanda B. Parrish, Susan Natoli, Nancy Hassell, Jelena P. Berglund, Irwin M. Liu, Denise C. Snyder, Mark Stacy, Valerie Amspacher, Bruce K. Burnett, and Jackie B. Rimmler
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Research Report ,Academic Medical Centers ,Clinical Trials as Topic ,Internet ,Full-time ,business.industry ,General Neuroscience ,Advisory Committees ,Food and Drug Administration Amendments Act of 2007 ,Legislation ,General Medicine ,Public relations ,General Biochemistry, Genetics and Molecular Biology ,Clinical trial ,Public law ,Resource (project management) ,Original Research Articles ,Agency (sociology) ,Humans ,Medicine ,The Internet ,Investments ,General Pharmacology, Toxicology and Pharmaceutics ,business - Abstract
The Food and Drug Administration Amendments Act of 2007 (FDAAA 2007, US Public Law 110-98) mandated registration and reporting of results for applicable clinical trials (ACTs). Meeting these registration and results reporting requirements has proven to be a challenge for the academic research community. Duke Medicine has made compliance with registration and results reporting a high priority. In order to create uniformity across a large institution, a written policy was created describing requirements for clinical trials disclosure. Furthermore, a centralized resource group was formed with three full time staff members. The group not only ensures compliance with FDAAA 2007, it also acts as a resource for study teams providing hands-on support, reporting, training and ongoing education. Intensive resourcing for results reporting has been crucial for success. Due to implementation of the institutional policy and creation of centralized resources, compliance with FDAAA 2007 has increased dramatically at Duke Medicine for both registration and results reporting. A consistent centralized approach has enabled success in the face of changing agency rules and new legislation.
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- 2014
- Full Text
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48. Comprehensive hands-on training for influenza vaccine manufacturing: A WHO-BARDA-BTEC partnership for global workforce development
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Gary Gilleskie, Ruben G. Carbonell, Patty Brown, Jennifer Ruiz, and Bruce K. Burnett
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Medical education ,Quality management system ,Transfer of training ,Influenza vaccine ,Preparedness ,Professional development ,Global workforce ,Business ,Workforce development ,Molecular Biology ,Biochemistry ,Human services - Abstract
The critical need for enhancing influenza pandemic preparedness in many developing nations has led the World Health Organization (WHO) and the Biomedical Advanced Research and Development Authority (BARDA), part of the U.S. Department of Health and Human Services (HHS), to develop an international influenza vaccine capacity-building program. Among the critical limitations faced by many of these nations is lack of access to training programs for staff supporting operations within vaccine production facilities. With support from BARDA, the Biomanufacturing Training and Education Center (BTEC) at North Carolina State University has addressed this need for training by developing and delivering a comprehensive training program, consisting of three courses: Fundamentals of cGMP Influenza Vaccine Manufacturing, Advanced Upstream Processes for Influenza Vaccine Manufacturing, and Advanced Downstream Processes for Influenza Vaccine Manufacturing. The courses cover process design, transfer, and execution at manufacturing scale, quality systems, and regulations covering both manufacturing and approval of pandemic vaccines. The Fundamentals course focuses on the concepts, equipment, applicable regulations, and procedures commonly used to produce influenza vaccine. The two Advanced courses focus on process design, scale up, validation, and new technologies likely to improve efficiency of vaccine production. All three courses rely on a combination of classroom instruction and hands-on training in BTEC's various laboratories. Each course stands alone, and participants may take one or more of the three courses. Overall participant satisfaction with the courses has been high, and follow-up surveys show that participants actively transferred the knowledge they gained to the workplace. Future plans call for BTEC to continue offering the three courses and to create an online version of several modules of the Fundamentals course.
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- 2014
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49. Controlling Conformations of Diketopyrrolopyrrole-Based Conjugated Polymers: Role of Torsional Angle
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Mallari A. Naik, Satish Patil, Edmund K. Burnett, Alejandro L. Briseno, Thomas D. Anthopoulos, Nir Yaacobi-Gross, and Catherine Kanimozhi
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chemistry.chemical_classification ,Electron mobility ,Organic field-effect transistor ,Materials science ,Stereochemistry ,Polymer ,Conjugated system ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,General Energy ,chemistry ,Chemical physics ,Thiophene ,Copolymer ,Charge carrier ,Physical and Theoretical Chemistry ,Thin film - Abstract
Transport of charge carriers through conjugated polymers is strongly influenced by the presence and distribution of structural disorders. In the present work, structural defects caused by the presence of torsional.. angle were investigated in a diketopyrrolopyrrole (DPP)-based conjugated polymer. Two new copolymers of DPP were synthesized with varying torsional angles to trace the role of structural disorder. The optical properties of these copolymers in solution and thin film reveal the strong influence of torsional angle on their photophysical properties. A strong influence was observed on carrier transport properties of polymers in organic field-effect transistors (OFET) device geometry. The polymers based on phenyl DPP with higher torsional angle (PPTDPP-OD-TEG) resulted in high threshold voltage with less charge carrier mobility as compared to the polymer based on thiophene DPP (2DPP-OD-TEG) bearing a lower torsional angle. Carrier mobility and the molecular orientation of the conjugated polymers were correlated on the basis of grazing incidence X-ray scattering measurements showing the strong role of torsional angle introduced in the form of structural disorder. The results presented in this Article provide a deep insight into the sensitivity of structural disorder and its impact on the device performance of DPP-based conjugated polymers.
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- 2014
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50. Rubicene: a molecular fragment of C70 for use in organic field-effect transistors
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Alejandro L. Briseno, Lei Zhang, Fred Wudl, Timothy J. Mirabito, Yue Zhang, Stefan C. B. Mannsfeld, Stefan Trahan, Edmund K. Burnett, Hyunbok Lee, and Ali Mohebbi
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Organic semiconductor ,Electron mobility ,Materials science ,Monolayer ,Materials Chemistry ,Analytical chemistry ,Density functional theory ,Work function ,Field-effect transistor ,General Chemistry ,Electronic structure ,Ultraviolet photoelectron spectroscopy - Abstract
Rubicene, a molecular fragment of C70, is a promising organic semiconductor material that displays excellent electronic characteristics for use in organic field-effect transistors (OFETs). Bottom-gate/bottom-contact polycrystalline thin-film OFETs using rubicene exhibit a saturation hole mobility of 0.20 cm2 V−1 s−1 and a current on/off ratio (Ion/Ioff) of 1.0 × 104. In addition, the device performance can be improved with a mobility of 0.32 cm2 V−1 s−1 and Ion/Ioff of 2.5 × 104 with pentafluorobenzenethiol (PFBT) self-assembled monolayer (SAM) treatment on Au electrodes. To characterize the interfacial electronic structure and morphology of rubicene on Au and PFBT/Au, ultraviolet photoelectron spectroscopy (UPS), theoretical calculation with density functional theory (DFT) and grazing incidence X-ray diffraction (GIXD) were performed. With PFBT SAM treatment, the hole injection barrier from Au to rubicene is significantly decreased from 1.15 to 0.48 eV due to the formation of a large interface dipole on Au that increased its work function from 4.33 to 5.67 eV. Furthermore, PFBT SAM treatment also induces an “edge-on” configuration of rubicene, which can lead to the increase in carrier mobility. These results indicate that rubicene can serve as a benchmark organic semiconductor for model charge transport studies and in various organic electronic devices.
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- 2014
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