491 results on '"Tibben A"'
Search Results
2. Metabolic Disposition of Lurbinectedin, a Potent Selective Inhibitor of Active Transcription of Protein-Coding Genes, in Nonclinical Species and Patients
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P, Aviles, R, Altares, L, van Andel, R, Lubomirov, S, Fudio, H, Rosing, F M, Márquez Del Pino, M M, Tibben, G, Benedit, L, Nan-Offeringa, X E Luepke, Estefan, A, Francesch, A, Zeaiter, C, Cuevas, J H M, Schellens, and J H, Beijnen
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Male ,Pharmacology ,Feces ,Lung Neoplasms ,Animals ,Humans ,Pharmaceutical Science ,Female ,Heterocyclic Compounds, 4 or More Rings ,Small Cell Lung Carcinoma ,Carbolines ,Rats - Abstract
Lurbinectedin is a novel and potent selective inhibitor of active transcription of protein-coding genes, triggering apoptosis of cancerous cells. It has been approved for the treatment of patients with metastatic small-cell lung cancer with disease progression on or after platinum-based chemotherapy. Studies exploring the disposition and metabolism of lurbinectedin were performed in vitro and in vivo (by intravenous administration of lurbinectedin). Low blood cell partitioning for lurbinectedin in rats, nonhuman primates (NHP), and humans was determined as 23.4%, 29.8%, and 9.8%, respectively. Protein binding was very high (95%) in total plasma (rat, NHP, and human), albumin, and
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- 2022
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3. Is Behavioural Therapy a New Treatment Option for Task-Specific Dystonia in Athletes? A Case Series
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Marleen Ieke Tibben, Erik van Wensen, Beorn Nijenhuis, and Johannes Zwerver
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General Medicine - Published
- 2023
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4. A simple extemporaneous oral suspension of aprepitant yields sufficient pharmacokinetic exposure in children
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A Laura Nijstad, Evelien de Vos-Kerkhof, Catherine F Enters-Weijnen, Marianne D van de Wetering, Wim J E Tissing, Lidwien M Hanff, Rogier Lange, Matthijs M Tibben, Hilde Rosing, Arief Lalmohamed, C Michel Zwaan, Alwin D R Huitema, and Pediatrics
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Oncology ,Pharmacology (medical) - Abstract
Introduction Aprepitant is used for the treatment of chemotherapy induced nausea and vomiting. A liquid formulation is needed for treatment of young children. However, the commercial (powder for) suspension was not available worldwide for a prolonged period of time and, therefore, a 10 mg/mL aprepitant oral suspension was extemporarily prepared to prevent suboptimal antiemetic treatment. The current pharmacokinetic study was developed to investigate whether this extemporaneous oral suspension offers an appropriate treatment option. Methods From 49 pediatric patients (0.7–17.9 years) 235 plasma concentrations were collected. Patients were either treated with our extemporaneous oral suspension (n = 26; 53%), commercially available capsules (n = 18; 37%), or the intravenous prodrug formulation of aprepitant (fosaprepitant, n = 5; 10%). Pharmacokinetic analyses were performed using nonlinear mixed effects modelling. Results A one-compartment model adequately described the pharmacokinetics of aprepitant in children. The bioavailability of the extemporaneous oral suspension was not significantly different to that of the capsules (P = 0.26). The observed bioavailability throughout the total population was 83% (95% CI 69%-97%). The absorption of the extemporaneous oral suspension was 39.4% (95%CI 19.5–57.4%) faster than that of capsules (mean absorption time of 1.78 h (95%CI 1.32–2.35), but was comparable to that of the commercial oral suspension. The median area under the curve after (fos)aprepitant was 22.2 mg/L*h (range 8.9–50.3 mg/L*h) on day 1. Conclusion Our extemporaneous oral suspension is an adequate alternative for the commercially (un)available oral suspension in young children. An adequate exposure to aprepitant in children was yielded and the bioavailability of the extemporaneous suspension was comparable to capsules.
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- 2023
5. Patients’ and surgeons’ experiences after failed breast reconstruction: A qualitative study
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Casimir A.E. Kouwenberg, Sohal Y. Ismail, Jessica P. Gopie, Lothar E. van Hoogdalem, Aad Tibben, Leonieke W. Kranenburg, Marc A.M. Mureau, Psychiatry, and Plastic and Reconstructive Surgery and Hand Surgery
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Adult ,medicine.medical_specialty ,Patients ,Mammaplasty ,media_common.quotation_subject ,medicine.medical_treatment ,Breast Neoplasms ,030230 surgery ,Grounded theory ,Interviews as Topic ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,medicine ,Humans ,Treatment Failure ,Qualitative Research ,Aged ,media_common ,Surgeons ,Physician-Patient Relations ,business.industry ,General surgery ,Middle Aged ,Surgery ,Clinical Practice ,Feeling ,030220 oncology & carcinogenesis ,Quality of Life ,Female ,Personal experience ,business ,Breast reconstruction ,Qualitative research ,Cohort study - Abstract
Summary Background The goal of postmastectomy breast reconstruction (BR) is to improve the quality of life of patients. However, complications following autologous (A-BR) and implant-based breast reconstruction (I-BR) occur frequently and may even lead to BR-failure, which can be a distressing event for both patients and surgeons. The current study therefore looks at the experiences of both patients and surgeons after a BR-failure. Methods Patients with a failed BR from a large multicenter cohort study and participating plastic surgeons were invited to participate in semi-structured interviews focusing on their experiences. The interviews were analyzed according to the principles of grounded theory. Results Fourteen patients with a failed I-BR, four patients with a failed A-BR and four plastic surgeons participated. Three main categories emerged from the data: personal experiences with BR-failure, the motives for a redo of a failed BR, and patient-surgeon communication. Patients would like to be treated with more attention to their personal feelings and lives, instead of being approached from a purely medical-technical perspective. Surgeons may experience feelings of guilt leading to the strong urge to fix the failed BR, whereas patients may be less inclined to undergo additional operations. Patients want to know what the choice for a particular type of BR would mean to their personal lives. The impact of I-BR-failure may be underestimated and requires the same degree of intensive aftercare and attention. Conclusions Implementing the recommendations of this study in clinical practice may facilitate improvements in how both patients and surgeons cope with a BR-failure.
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- 2021
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6. Overestimation of the effect of (fos)aprepitant on intravenous dexamethasone pharmacokinetics requires adaptation of the guidelines for children with chemotherapy-induced nausea and vomiting
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A Laura, Nijstad, Evelien, de Vos-Kerkhof, Catherine F, Enters-Weijnen, Marianne D, van de Wetering, Wim J E, Tissing, Matthijs M, Tibben, Hilde, Rosing, Arief, Lalmohamed, Alwin D R, Huitema, and C Michel, Zwaan
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Adult ,Tandem Mass Spectrometry ,Vomiting ,Morpholines ,Humans ,Antiemetics ,Antineoplastic Agents ,Nausea ,Drug Therapy, Combination ,Child ,Aprepitant ,Dexamethasone ,Chromatography, Liquid - Abstract
Chemotherapy-induced nausea and vomiting (CINV) are common side effects in pediatric oncology treatment. Besides 5-HTIn total, 65 children (0.6-17.9 years), receiving intravenous or oral antiemetic therapy (dexamethasone ± aprepitant) as standard of care, were included. 305 dexamethasone plasma concentrations were determined using LC-MS/MS. An integrated dexamethasone and aprepitant pharmacokinetic model was developed using non-linear mixed effects modelling in order to investigate the effect of aprepitant administration on dexamethasone CL.In this population, dexamethasone CL in patients with concomitant administration of aprepitant was reduced by approximately 30% of the uninhibited CL (23.3 L/h (95% confidence interval 20.4-26.0)). This result is not consistent with the results of adult studies (50% reduction). This difference was not age dependent, but might be related to the route of administration of dexamethasone. Future studies are needed to assess the difference in oral/intravenous dexamethasone.When dexamethasone is given intravenously as a component of triple therapy to prevent CINV in children, we advise to reduce the dexamethasone dose by 30% instead of 50%.
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- 2022
7. Mindfulness-Based Stress Reduction in Pre-symptomatic Genetic Frontotemporal Dementia
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Jackie M. Poos, Esther van den Berg, Janne M. Papma, Fleur C. van der Tholen, Harro Seelaar, Laura Donker Kaat, J Anneke Kievit, Aad Tibben, John C. van Swieten, Lize C. Jiskoot, Radiology & Nuclear Medicine, Neurology, and Clinical Genetics
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Psychiatry and Mental health ,SDG 3 - Good Health and Well-being - Abstract
Pre-symptomatic frontotemporal dementia (FTD) mutation carriers and first-degree family members that are 50% at-risk for FTD may experience symptoms of anxiety and depression as a result of the ambiguity of when or if symptoms of the disease will manifest. We conducted a pilot study to investigate the use of an online mindfulness-based stress reduction (MBSR) course to reduce symptoms of anxiety and depression in presymptomatic frontotemporal dementia (FTD) mutation carriers and individuals 50% at-risk. Seven known mutation carriers and six individuals 50% at-risk completed a standardized 8-week MBSR course, and filled out pre- and post and two-month follow-up questionnaires. The primary outcome measure was the Hospital Anxiety and Depression Scale (HADS). Measures of psychological distress (SCL-90-R), coping style (UCL), quality of life (SF-36) and mindfulness skills (FFMQ) were administered as secondary outcome. Group effects were analyzed with repeated measures ANOVA or Friedman's test, and the individual reliability change index (RCI) was calculated per participant for each outcome measure. Semi-quantitative data included an evaluation and process measure post-intervention. Significant decline was found on the HADS-A post-intervention and after 2 months (p = 0.01), with 54% and 62% of participants demonstrating a clinically significant RCI, respectively. On the HADS-D, significant decline was found 2 months post-intervention (p = 0.04), which was driven by 23% of participants whom had a clinically significant RCI. Additional changes were found between baseline and post-intervention on the seeking distraction and reassuring thoughts subscales of the UCL, the depression and interpersonal sensitivity subscales of the SCL, the observe subscale of the FFMQ, and on physical role limitations of the SF-36 (all p < 0.05). The process evaluation form indicated that the course was found beneficial by participants, and that they applied it in a wide range of everyday situations. This exploratory pilot study indicates the feasibility of MBSR in reducing anxiety and depression in presymptomatic FTD mutation carriers and 50% at-risk individuals. A randomized controlled trial is necessary to replicate these results.
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- 2022
8. sj-docx-1-opp-10.1177_10781552221089243 - Supplemental material for A simple extemporaneous oral suspension of aprepitant yields sufficient pharmacokinetic exposure in children
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Nijstad, A Laura, de Vos-Kerkhof, Evelien, Enters-Weijnen, Catherine F, van de Wetering, Marianne D, Tissing, Wim J E, Hanff, Lidwien M, Lange, Rogier, Tibben, Matthijs M, Rosing, Hilde, Lalmohamed, Arief, Zwaan, C Michel, and Huitema, Alwin D R
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FOS: Clinical medicine ,111599 Pharmacology and Pharmaceutical Sciences not elsewhere classified ,111299 Oncology and Carcinogenesis not elsewhere classified - Abstract
Supplemental material, sj-docx-1-opp-10.1177_10781552221089243 for A simple extemporaneous oral suspension of aprepitant yields sufficient pharmacokinetic exposure in children by A Laura Nijstad, Evelien de Vos-Kerkhof, Catherine F Enters-Weijnen, Marianne D van de Wetering, Wim J E Tissing, Lidwien M Hanff, Rogier Lange, Matthijs M Tibben, Hilde Rosing, Arief Lalmohamed, C Michel Zwaan and Alwin D R Huitema in Journal of Oncology Pharmacy Practice
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- 2022
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9. sj-docx-1-opp-10.1177_10781552221089243 - Supplemental material for A simple extemporaneous oral suspension of aprepitant yields sufficient pharmacokinetic exposure in children
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Nijstad, A Laura, de Vos-Kerkhof, Evelien, Enters-Weijnen, Catherine F, van de Wetering, Marianne D, Tissing, Wim J E, Hanff, Lidwien M, Lange, Rogier, Tibben, Matthijs M, Rosing, Hilde, Lalmohamed, Arief, Zwaan, C Michel, and Huitema, Alwin D R
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FOS: Clinical medicine ,111599 Pharmacology and Pharmaceutical Sciences not elsewhere classified ,111299 Oncology and Carcinogenesis not elsewhere classified - Abstract
Supplemental material, sj-docx-1-opp-10.1177_10781552221089243 for A simple extemporaneous oral suspension of aprepitant yields sufficient pharmacokinetic exposure in children by A Laura Nijstad, Evelien de Vos-Kerkhof, Catherine F Enters-Weijnen, Marianne D van de Wetering, Wim J E Tissing, Lidwien M Hanff, Rogier Lange, Matthijs M Tibben, Hilde Rosing, Arief Lalmohamed, C Michel Zwaan and Alwin D R Huitema in Journal of Oncology Pharmacy Practice
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- 2022
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10. A Novel Instructional Design Based on Cognitive Apprenticeship Model to Enhance Teaching Network Management
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Madhav Mukherjee, Ngoc Thuy LE, William J. Tibben, Pairat Thorncharoensri, and Jun Shen
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- 2021
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11. P-Glycoprotein (ABCB1/MDR1) Controls Brain Penetration and Intestinal Disposition of the PARP1/2 Inhibitor Niraparib
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Nancy H.C. Loos, Hilde Rosing, Margarida L. F. Martins, Maria C. Lebre, Danielle de Jong, Alfred H. Schinkel, Jos H. Beijnen, Matthijs M. Tibben, and Sümeyra Mucuk
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Genetically modified mouse ,Indazoles ,Abcg2 ,CYP3A ,Metabolite ,Pharmaceutical Science ,Pharmacology ,Poly(ADP-ribose) Polymerase Inhibitors ,Madin Darby Canine Kidney Cells ,chemistry.chemical_compound ,Mice ,Dogs ,Pharmacokinetics ,Piperidines ,Tetrahydroisoquinolines ,Drug Discovery ,Distribution (pharmacology) ,Animals ,Cytochrome P-450 CYP3A ,Tissue Distribution ,ATP Binding Cassette Transporter, Subfamily B, Member 1 ,CYP3A4 ,biology ,Chemistry ,Brain ,Biological Transport ,In vitro ,Intestines ,biology.protein ,Molecular Medicine ,Acridines - Abstract
Niraparib (Zejula), a selective oral PARP1/2 inhibitor registered for ovarian, fallopian tube, and primary peritoneal cancer treatment, is under investigation for other malignancies, including brain tumors. We explored the impact of the ABCB1 and ABCG2 multidrug efflux transporters, the OATP1A/1B uptake transporters, and the CYP3A drug-metabolizing complex on oral niraparib pharmacokinetics, using wild-type and genetically modified mouse and cell line models. In vitro, human ABCB1 and mouse Abcg2 transported niraparib moderately. Compared to wild-type mice, niraparib brain-to-plasma ratios were 6- to 7-fold increased in Abcb1a/1b-/- and Abcb1a/1b;Abcg2-/- but not in single Abcg2-/- mice, while niraparib plasma exposure at later time points was ∼2-fold increased. Niraparib recovery in the small intestinal content was markedly reduced in the Abcb1a/1b-deficient strains. Pretreatment of wild-type mice with oral elacridar, an ABCB1/ABCG2 inhibitor, increased niraparib brain concentration and reduced small intestinal content recovery to levels observed in Abcb1a/1b;Abcg2-/- mice. Oatp1a/1b deletion did not significantly affect niraparib oral bioavailability or liver distribution but decreased metabolite M1 liver uptake. No significant effects of mouse Cyp3a ablation were observed, but overexpression of transgenic human CYP3A4 unexpectedly increased niraparib plasma exposure. Thus, Abcb1 deficiency markedly increased niraparib brain distribution and reduced its small intestinal content recovery, presumably through reduced biliary excretion and/or decreased direct intestinal excretion. Elacridar pretreatment inhibited both processes completely. Clinically, the negligible role of OATP1 and CYP3A could be advantageous for niraparib, diminishing drug-drug interaction or interindividual variation risks involving these proteins. These findings may support the further clinical development and application of niraparib.
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- 2021
12. Implementing non‐invasive prenatal testing (NIPT) in the Netherlands: An interview study exploring opinions about and experiences with societal pressure, reimbursement, and an expanding scope
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Adriana Kater-Kuipers, Attie T.J.I. Go, Sam Riedijk, Inez de Beaufort, Robert-Jan H. Galjaard, Iris M. Bakkeren, Aad Tibben, Eline M. Bunnik, Public Health, Obstetrics & Gynecology, and Clinical Genetics
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Adult ,psychosocial ,medicine.medical_specialty ,Genetic counseling ,Decision‐making ,Reimbursement Mechanisms ,deliberation ,03 medical and health sciences ,0302 clinical medicine ,Pregnancy ,Prenatal Diagnosis ,medicine ,Humans ,Genetic Testing ,Genetics (clinical) ,Reimbursement ,Netherlands ,0303 health sciences ,genetic counseling ,Scope (project management) ,030305 genetics & heredity ,Original Articles ,reimbursement ,Test (assessment) ,expanding scope ,Social Class ,030220 oncology & carcinogenesis ,Family medicine ,Life expectancy ,Female ,Original Article ,Psychology ,Psychosocial ,Inclusion (education) ,NIPT ,societal pressure ,Diversity (business) - Abstract
The noninvasive prenatal test (NIPT) as the first trimester prenatal screening (FTS) for trisomies 21, 18, and 13 is offered to all pregnant women in the Netherlands. NIPT using genome sequencing allows for an expansion of the scope of FTS and the introduction of NIPT gives rise to ethical and societal concerns about deliberated decision‐making, pressure to engage in screening, and possible lack of equal access due to the financial contribution (€175) to NIPT. We explored the opinions and experiences of pregnant women, who were offered FTS, about these concerns, and the possibility of a broadened scope. Nineteen pregnant women representing a diversity of backgrounds were interviewed using a semi‐structured interview guide. Eight women did not opt for prenatal screening while 11 did (NIPT = 4, combined test = 7). Women experienced a free choice to accept or decline prenatal screening, despite sometimes receiving advice from others. Prior to pretest counseling, some women had already deliberated about what an abnormal test result would mean to them. Others accepted or declined FTS without deliberation. The current Dutch policy of requiring a co‐payment was acceptable to some, who believed that it functioned as a threshold to think carefully about FTS. Others were concerned that a financial threshold would lead to unequal access to screening. Finally, pregnant women found it difficult to formulate opinions on the scope of FTS, because of lack of knowledge. Life expectancy, severity, and treatability were considered important criteria for the inclusion of a condition in NIPT.
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- 2019
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13. P‐glycoprotein (MDR1/ABCB1) controls brain accumulation and intestinal disposition of the novel TGF‐β signaling pathway inhibitor galunisertib
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Li, Wenlong, Tibben, Matthijs, Wang, Yaogeng, Lebre, Maria C, Rosing, Hilde, Beijnen, Jos H, Schinkel, Alfred H, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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Genetically modified mouse ,Cancer Research ,ATP Binding Cassette Transporter, Subfamily B ,Abcg2 ,CYP3A ,Herb-Drug Interactions ,Organic Anion Transporters ,P-glycoprotein ,Pharmacology ,Madin Darby Canine Kidney Cells ,Mice ,03 medical and health sciences ,Dogs ,0302 clinical medicine ,Pharmacokinetics ,Transforming Growth Factor beta ,Tetrahydroisoquinolines ,ATP Binding Cassette Transporter, Subfamily G, Member 2 ,Animals ,Cytochrome P-450 CYP3A ,Humans ,Galunisertib ,Tissue Distribution ,cytochrome P450-3A ,Receptor ,biology ,CYP3A4 ,Chemistry ,Brain ,Oatp1a/1b ,Neoplasm Proteins ,brain accumulation ,galunisertib ,Oncology ,oral availability ,030220 oncology & carcinogenesis ,Quinolines ,biology.protein ,Acridines ,Pyrazoles ,Female ,intestinal disposition ,Signal Transduction - Abstract
Galunisertib (LY2157299), a promising small-molecule inhibitor of the transforming growth factor-beta (TGF-β) receptor, is currently in mono- and combination therapy trials for various cancers including glioblastoma, hepatocellular carcinoma and breast cancer. Using genetically modified mouse models, we investigated the roles of the multidrug efflux transporters ABCB1 and ABCG2, the OATP1A/1B uptake transporters and the drug-metabolizing CYP3A complex in galunisertib pharmacokinetics. In vitro, galunisertib was vigorously transported by human ABCB1, and moderately by mouse Abcg2. Orally administered galunisertib (20 mg/kg) was very rapidly absorbed. Galunisertib brain-to-plasma ratios were increased by ~24-fold in Abcb1a/1b-/- and Abcb1a/1b;Abcg2-/- mice compared to wild-type mice, but not in single Abcg2-/- mice, whereas galunisertib oral availability was not markedly affected. However, recovery of galunisertib in the small intestinal lumen was strongly reduced in Abcb1a/1b-/- and Abcb1a/1b;Abcg2-/- mice. Oral coadministration of the ABCB1/ABCG2 inhibitor elacridar boosted galunisertib brain accumulation in wild-type mice to equal the levels seen in Abcb1a/1b;Abcg2-/- mice. Oatp1a/1b deficiency did not alter oral galunisertib pharmacokinetics or liver distribution. Cyp3a-/- mice showed a 1.9-fold higher plasma AUC0-1 hr than wild-type mice, but this difference disappeared over 8 hr. Also, transgenic human CYP3A4 overexpression did not significantly alter oral galunisertib pharmacokinetics. Abcb1 thus markedly restricts galunisertib brain penetration and affects its intestinal disposition, possibly through biliary excretion. Elacridar coadministration could fully inhibit both processes, without causing acute toxicity. Moreover, mouse Cyp3a, but not human CYP3A4, may eliminate galunisertib at high plasma concentrations. These insights may help to guide the further clinical development and application of galunisertib.
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- 2019
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14. Abstract P4-12-08: Patients' and surgeons' experiences after failed breast reconstruction: A qualitative study
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SY Ismail, LE Hoogdalem, A Tibben, CA Kouwenberg, Marc A.M. Mureau, JP Gopie, and LW Kranenburg
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Cancer Research ,Reconstructive surgery ,medicine.medical_specialty ,business.industry ,media_common.quotation_subject ,General surgery ,medicine.disease ,Grounded theory ,Breast cancer ,Oncology ,Feeling ,Medicine ,Personal experience ,business ,Breast reconstruction ,Cohort study ,Qualitative research ,media_common - Abstract
Background: Breast cancer reconstructive surgery is supposed to contribute to patients' body image and quality of life. However, complications after autologous breast reconstruction (A-BR) and implant-based breast reconstruction (I-BR) do occur in approximately 40% of the women, and may even lead to complete failure in rare cases. This study explores both patients' and surgeons' experiences after failed breast reconstruction. Increased knowledge in this field could help to improve not only the care for women with failed breast cancer reconstructive surgery but may also help to guide professionals in dealing with such failures. Methods: Patients with reconstructive failure form a large multicenter cohort study and participating plastic surgeons were invited to participate in this study. A topic list consisting of ten topics served as a general outline of a semi-structured interview on their experiences with the reconstructive failure, lasting about one hour. The interview data were transcribed and after that analyzed according to the principles of grounded theory by two researchers independently of each other. Data were coded in NVivo software. Next, data were discussed in a larger team, thereby moving back and forth between data and emerging theory. Results: Fourteen patients with a failed I-BR, four patients with failed A-BR and four plastic surgeons participated in this study. Three main categories emerged from the data: personal experiences, the motivation for a redo of the failed reconstructive surgery and patient-doctor communication. With regard to personal experiences, a main patient category was the importance of being (appreciated as) a person as a whole, in his/her specific context (versus focusing on reconstructive technique). This in contrast to the surgeons, for whom it did matter whether the failure concerned an I-BR or A-BR. The latter was perceived as more intense. Some took it as a personal failure, leading to insecurity and feelings of regret towards the patient. This was especially true if they felt a strong bond with that particular patient. With regard to motivation for a redo of the failed reconstructive surgery, both patients and surgeons emphasized the importance of shared decision making. Nevertheless, patients seemed to remain more ambivalent than surgeons about pursuing additional reconstruction after failure. Finally, regarding patient-doctor communication, we found that surgeons were more distant or reflective on these matters, whereas patients expressed their experiences in a more emotional way. Patients expressed a desire to be seen and treated as an unique individual. Experiencing trustfulness, sincerity and empathy from the surgeon in discussing the failure were highly valued. Discussion: Implementing the results of this study in clinical practice may facilitate coping with the distressing or even traumatic event of failed breast reconstruction, in both patients and surgeons. Citation Format: Kouwenberg CA, Hoogdalem LE, Gopie JP, Tibben A, Mureau MA, Ismail SY, Kranenburg LW. Patients' and surgeons' experiences after failed breast reconstruction: A qualitative study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-12-08.
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- 2019
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15. Contributors to and consequences of burnout among clinical genetic counselors in the United States
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MaryAnn Campion, Colleen Caleshu, Helen Kim, Jehannine Austin, Julia Silver, and Aad Tibben
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Mindfulness ,health care facilities, manpower, and services ,media_common.quotation_subject ,education ,Burnout ,Burnout, Psychological ,health services administration ,medicine ,Humans ,Burnout, Professional ,Genetics (clinical) ,media_common ,Secondary data ,Mental health ,United States ,Distress ,Counselors ,Feeling ,Anxiety ,Female ,Psychological resilience ,medicine.symptom ,Empathy ,Psychology ,psychological phenomena and processes ,Clinical psychology - Abstract
Prior research has found that many genetic counselors (GCs) experience burnout. Studies of other clinicians have demonstrated that burnout can have significant detrimental consequences for clinicians, patients, and the healthcare system. We sought to explore the prevalence of, contributors to, and consequences of burnout among GCs. We performed a secondary data analysis of baseline data from Me-GC, a randomized controlled trial of meditation for GCs. We applied a systems model of burnout proposed by the National Academy of Medicine (NAM), which depicts burnout arising from a combination of contributors that include both work system and individual mediating factors, and then leading to consequences. Validated self-report scales were used to measure burnout and most contributors and consequences. Female and white GCs were over-represented in our sample. Over half (57.2%) of the 397 participants had Professional Fulfillment Index scores indicative of burnout. Multiple potential contributors were associated with burnout, consistent with its known multifactorial nature. Among work system factors, higher levels of burnout were associated with insufficient administrative support, lack of autonomy, and not feeling valued by non-GC colleagues. Individual mediating factors associated with greater burnout included higher levels of anxiety, depression, and stress. Participants with lower levels of burnout reported greater mindfulness, resilience, and use of professional self-care behaviors. Among variables categorized as consequences, higher levels of burnout were associated with lower levels of empathy, counseling alliance, and positive unconditional regard, as well as higher reactive distress, and a greater desire to reduce the amount of time spent on clinical care. Given the prevalence and potential consequences of burnout observed here, it is imperative that the field take steps to mitigate burnout risk.
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- 2021
16. Parents, their children, whole exome sequencing and unsolicited findings: growing towards the child’s future autonomy
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Tibben, Aad, Dondorp, Wybo, Cornelis, Candice, Knoers, Nine, Brilstra, Eva, van Summeren, Marieke, Bolt, Ineke, OFR - Ethics Institute, LS Wijsgerige Ethiek, OFR - Ethics Institute, LS Wijsgerige Ethiek, Clinical Genetics, Public Health, RS: CAPHRI - R6 - Promoting Health & Personalised Care, and Metamedica
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Adult ,Male ,Parents ,RETURN ,DISCLOSURE ,Adolescent ,Inclusion (disability rights) ,media_common.quotation_subject ,PATIENTS VIEWS ,Genetic Counseling ,PREFERENCES ,Truth Disclosure ,Article ,Developmental psychology ,incidental findings ,SECONDARY VARIANTS ,Exome Sequencing ,Genetics ,Humans ,Genetics(clinical) ,Child ,Genetics (clinical) ,Exome sequencing ,media_common ,communication ,Genetic Carrier Screening ,RESEARCH PARTICIPANTS ,Infant ,Cognition ,ethics ,PERSPECTIVES ,Child, Preschool ,Carrier status ,Female ,Psychology ,Autonomy - Abstract
In a previous study we found that parents of children with developmental delay (DD) favoured acceptance of unsolicited findings (UFs) for medically actionable conditions in childhood, but that preferences diverged for UFs with no medical actionability, or only in adulthood, and regarding carrier status. Sometimes the child’s future autonomy formed a reason for withholding UFs for the present, despite an unfavourable prognosis concerning the child’s cognitive capabilities. This might be different for children undergoing whole exome sequencing (WES) for reasons other than DD and who are expected to exert future autonomy. This is the focus of the current study. We conducted nine qualitative, semi-structured interviews with parents of children, ages
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- 2021
17. Development and validation of a combined liquid chromatography tandem-mass spectrometry assay for the quantification of aprepitant and dexamethasone in human plasma to support pharmacokinetic studies in pediatric patients
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A. Laura Nijstad, Alwin D. R. Huitema, C. Michel Zwaan, Evelien de Vos-Kerkhof, Hilde Rosing, A. Gebretensae, Jos H. Beijnen, Matthijs M. Tibben, and Pediatrics
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Male ,Bioanalysis ,Adolescent ,Clinical Biochemistry ,Tandem mass spectrometry ,Sensitivity and Specificity ,030226 pharmacology & pharmacy ,01 natural sciences ,Biochemistry ,Dexamethasone ,Analytical Chemistry ,Matrix (chemical analysis) ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,Tandem Mass Spectrometry ,Liquid chromatography–mass spectrometry ,medicine ,Humans ,Protein precipitation ,Child ,Aprepitant ,Detection limit ,Chromatography ,Chemistry ,010401 analytical chemistry ,Reproducibility of Results ,Cell Biology ,General Medicine ,0104 chemical sciences ,Linear Models ,Female ,Chromatography, Liquid ,medicine.drug - Abstract
A pharmacokinetic study was set up to investigate the pharmacokinetics of the anti-emetic agents aprepitant and dexamethasone and the drug-drug interaction between these drugs in children. In order to quantify aprepitant and dexamethasone, a liquid chromatography-tandem mass spectrometry assay was developed and validated for the simultaneous analysis of aprepitant and dexamethasone. Protein precipitation with acetonitrile-methanol (1:1, v/v) was used to extract the analytes from plasma. The assay was based on reversed-phase chromatography coupled with tandem mass spectrometry detection operating in the positive ion mode. The assay was validated based on the guidelines on bioanalytical methods by the US Food and Drug Administration and European Medicines Agency. The calibration model was linear and a weighting factor of 1/concentration2 was used over the range of 0.1–50 ng/mL for aprepitant and 1–500 ng/mL for dexamethasone. Intra-assay and inter-assay bias were within ±20% for all analytes at the lower limit of quantification and within ±15% at remaining concentrations. Dilution integrity tests showed that samples exceeding the upper limit of quantification can be diluted 100 times in control matrix. Stability experiments showed that the compounds are stable in the biomatrix for 25 h at room temperatures and 89 days at −20 °C. This assay is considered suitable for pharmacokinetic studies and will be used to study the drug-drug interaction between aprepitant and dexamethasone in pediatric patients.
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- 2021
18. Simultaneous quantification of abemaciclib and its active metabolites in human and mouse plasma by UHPLC-MS/MS
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Alfred H. Schinkel, Jos H. Beijnen, Alejandra Martínez-Chávez, Karen A.M. de Jong, Matthijs M. Tibben, and Hilde Rosing
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Analyte ,Clinical Biochemistry ,Pharmaceutical Science ,Aminopyridines ,Mass spectrometry ,01 natural sciences ,Analytical Chemistry ,chemistry.chemical_compound ,Mice ,Column chromatography ,Pharmacokinetics ,Tandem Mass Spectrometry ,Drug Discovery ,Protein precipitation ,Potency ,Animals ,Humans ,Spectroscopy ,Active metabolite ,Chromatography, High Pressure Liquid ,Chromatography ,010405 organic chemistry ,Chemistry ,010401 analytical chemistry ,Reproducibility of Results ,0104 chemical sciences ,Ammonium bicarbonate ,Pharmaceutical Preparations ,Benzimidazoles - Abstract
Abemaciclib is the third cyclin-dependent kinase 4 and 6 inhibitor approved for the treatment of advanced or metastatic breast cancer. In humans, abemaciclib is extensively metabolized by CYP3A4 with the formation of three active metabolites: N-desethylabemaciclib (M2), hydroxyabemaciclib (M20) and hydroxy-N-desethylabemaciclib (M18). These metabolites showed similar potency compared to the parent drug and were significantly abundant in plasma circulation. Thus, M2, M20, and M18 may contribute to the clinical activity of abemaciclib. For this reason, an UHPLC-MS/MS method for the simultaneous quantification of abemaciclib and its active metabolites in human and mouse plasma was developed and validated to support further clinical or preclinical investigations on this drug. Samples were processed by protein precipitation with acetonitrile, followed by supernatant dilution and filtration. Chromatographic separation was performed on a Kinetex C18 column (150 × 2.1 mm ID, 2.6 μm) using gradient elution with 10 mM ammonium bicarbonate in water (eluent A) and in methanol-water (9:1, v/v, eluent B). This method was selective, linear, accurate and precise within the range of 1-600 ng/mL for abemaciclib, 0.5-300 ng/mL for M2 and M20, and 0.2-120 ng/mL for M18. Furthermore, stability of the analytes in human and mouse plasma samples in several conditions was demonstrated. Finally, this assay was successfully used in a preclinical pharmacokinetic study, where abemaciclib and its active metabolites were identified and quantified. Inter-species differences between human and mouse samples were encountered, especially in the formation of M20, where isomers of this compound were detected in mouse plasma, but not in human plasma. This was confirmed by high resolution-mass spectrometry (HR-MS) measurements.
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- 2021
19. Method for Reproducible Shipboard Segmented Flow Analysis Ammonium Measurement Using an In-House Reference Material for Quality Control
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Merinda McMahon, Andreas Marouchos, Stephen Tibben, Alicia Camac, Cassie Schwanger, Jack McDonald, Christine Rees, Kendall Sherrin, Peter Hughes, and Julie Janssens
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lcsh:QH1-199.5 ,Flow (psychology) ,NITROGEN ASSIMILATION ,Soil science ,Environmental Sciences & Ecology ,COLORIMETRIC DETERMINATION ,Ocean Engineering ,lcsh:General. Including nature conservation, geographical distribution ,Aquatic Science ,chemistry ,NUTRIENTS ,Oceanography ,01 natural sciences ,ESTUARINE ,03 medical and health sciences ,chemistry.chemical_compound ,Nitrate ,OCEAN ,nutrients ,PHYTOPLANKTON ,PHOSPHATE ,Ammonium ,Marine & Freshwater Biology ,Nitrite ,quality control ,lcsh:Science ,seawater ,030304 developmental biology ,Water Science and Technology ,0303 health sciences ,Reproducibility ,Global and Planetary Change ,Science & Technology ,STABILITY ,SEAWATER ,010401 analytical chemistry ,Repeatability ,0104 chemical sciences ,ammonium ,Certified reference materials ,lcsh:Q ,Seawater ,Life Sciences & Biomedicine ,Environmental Sciences ,shipboard analysis ,NITRATE - Abstract
Ammonium is a fundamental nutrient for phytoplankton growth in seawater and is a key component of the microbial loop. Ammonium measured in parallel with other nutrients is crucial in understanding the small temporal scale changes in oceanographic ecology. Despite the importance of measuring ammonium at sea, owing to its lability, there is no consensus on the best method. The lack of availability of certified reference materials for ammonium in seawater also makes it difficult to assess the accuracy and reproducibility of ammonium measurements. In this study we present a modified segmented flow analysis method using ortho-phthaldialdehyde (OPA) with fluorescence detection to measure ammonium at sea together with four other macro-nutrients (nitrate, nitrite, silicate and phosphate) in near real time. An in-house ammonium quality control (QC) material was produced to improve the accuracy and repeatability of the measurement at sea. The QC was prepared following two different methods and stored in two types of containers. The suitability of the in-house QC’s as a reference material were assessed onboard the RV Investigator in 2018 during two oceanographic voyages, including one on the repeat SR03 CLIVAR transect. This paper describes the production and assessment of the in-house QC for ammonium in seawater, providing groundwork for creating a short-term stable ammonium reference material for sea going voyages. The uncertainty of this method of ammonium measurement was found to be 0.10 μmol/L at ammonium concentration of 1.0 μmol/L. Results show that preparation of the QC inside a laminar flow cabinet and directly into 10 mL polypropylene sample tubes just prior to the commencement of the voyage improved its stability.
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- 2021
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20. A brief cognitive-behavioural treatment approach for PTSD and Dissociative Identity Disorder: A case report
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Agnes van Minnen and Marleen Tibben
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Dissociation (neuropsychology) ,Cognitive Behavioral Therapy ,Dissociative Identity Disorder ,Treatment outcome ,Experimental and Cognitive Psychology ,Cognition ,Dysfunctional family ,Dissociative Disorders ,medicine.disease ,Avoidant coping ,Stress Disorders, Post-Traumatic ,Experimental Psychopathology and Treatment ,Psychiatry and Mental health ,Clinical Psychology ,Posttraumatic stress ,Dissociative identity disorder ,Arts and Humanities (miscellaneous) ,Sexual abuse ,medicine ,Humans ,Female ,Child ,Psychology ,Clinical psychology - Abstract
Contains fulltext : 234230.pdf (Publisher’s version ) (Open Access) Background and objectives: We described a new treatment model for Posttraumatic Stress Disorder (PTSD) and Dissociative Identity Disorder (DID), based on cognitive-behavioural principles. In this model, dissociation is seen as a maladaptive avoidant coping strategy. In addition, we stress that patients have dysfunctional beliefs about dissociation. Both elements, avoidance behaviour and dysfunctional beliefs, are challenged during the brief, intensive trauma-focused treatment. When the PTSD-symptoms decrease, the patient is offered a fare-well ritual to say goodbye to their identities in one or more additional sessions. Methods: We illustrate this treatment approach with a case report of a woman with PTSD as a result of sexual abuse in her childhood, and DID with four identities. Treatment outcome was measured at intake, at pre-treatment, at post-treatment and at 3 and 6 months follow-up. Results After the short treatment of only 2 weeks, she no longer fulfilled the DSM-5 diagnostic criteria for PTSD nor DID. These results were maintained at the follow-ups. Limitations: Although we included a baseline-controlled time phase, it was not a controlled study, and only one patient was treated. Conclusions: This new treatment model for DID-patients is promising but results should be interpreted cautiously since we described only one patient. 6 p.
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- 2021
21. 'We Should View Him as an Individual': The Role of the Child's Future Autonomy in Shared Decision-Making About Unsolicited Findings in Pediatric Exome Sequencing
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Wybo Dondorp, Aad Tibben, M. J. H. van Summeren, G. de Wert, Ineke Bolt, Public Health, RS: GROW - R4 - Reproductive and Perinatal Medicine, RS: CAPHRI - R6 - Promoting Health & Personalised Care, and Metamedica
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Male ,Parents ,psychosocial implications ,RETURN ,Health (social science) ,medical genetics ,Adolescent ,media_common.quotation_subject ,Decision Making ,AMERICAN-COLLEGE ,Health informatics ,Pediatrics ,RECOMMENDATIONS ,ethical challenges ,incidental findings ,SDG 3 - Good Health and Well-being ,Argument ,Unsollicited findings ,medicine ,Future autonomy ,Humans ,Exome ,Genetic Testing ,CLINICAL EXOME ,Child ,Clinical sequencing ,Exome sequencing ,Shared decision making ,media_common ,Genetic testing ,Ethics ,medicine.diagnostic_test ,business.industry ,STATEMENT ,Health Policy ,Public relations ,Directive ,POLICY ,Issues, ethics and legal aspects ,Prima facie ,Philosophy of medicine ,Female ,business ,Psychology ,Decision Making, Shared ,Autonomy - Abstract
In debates about genetic testing of children, as well as about disclosing unsolicited findings (UFs) of pediatric exome sequencing, respect for future autonomy should be regarded as a prima facie consideration for not taking steps that would entail denying the future adult the opportunity to decide for herself about what to know about her own genome. While the argument can be overridden when other, morally more weighty considerations are at stake, whether this is the case can only be determined in concrete cases. Importantly, when children grow into adolescents, respect for future autonomy will have to give way to respecting their emerging autonomy. When pediatric exome sequencing is done for complex conditions not involving developmental delay, respect for the child’s future or emerging autonomy should be a primary consideration for those charged with deciding on behalf of the child. Building on what Emanuel and Emanuel have termed the ‘deliberative model’ of shared decision making, we argue that if parents fail to give these considerations their due, professionals should actively invite them to do so. Taking a directive stance may be needed in order to make sure that the future or emerging autonomy of the child are duly considered in the decision-making process, but also to help the parents and themselves to shape their respective roles as responsible care-givers.
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- 2020
22. Development and validation of an LC-MS/MS method for the quantitative analysis of milciclib in human and mouse plasma, mouse tissue homogenates and tissue culture medium
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Martínez-Chávez, Alejandra, Tibben, Matthijs M, Broeders, Jelle, Rosing, Hilde, Schinkel, Alfred H, Beijnen, Jos H, Afd Pharmacoepi & Clinical Pharmacology, Pharmacoepidemiology and Clinical Pharmacology, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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Bioanalysis ,Analyte ,Milciclib ,Clinical Biochemistry ,Pharmaceutical Science ,Tissue homogenates ,01 natural sciences ,CDK inhibitor ,Analytical Chemistry ,Mice ,chemistry.chemical_compound ,Tissue culture ,Plasma ,LC–MS/MS ,Tandem Mass Spectrometry ,Drug Discovery ,Animals ,Humans ,Protein precipitation ,Protein Kinase Inhibitors ,Spectroscopy ,Detection limit ,Chromatography ,010405 organic chemistry ,010401 analytical chemistry ,Extraction (chemistry) ,Reproducibility of Results ,Culture Media ,0104 chemical sciences ,Ammonium bicarbonate ,chemistry ,Quantitative analysis (chemistry) ,Chromatography, Liquid ,Tissue culture medium - Abstract
Milciclib is a promising cyclin-dependent kinase inhibitor currently in phase II clinical trials to treat several types of cancer. The first bioanalytical method for the quantitative analysis of milciclib in several biomatrices using liquid chromatography-tandem mass spectrometry is described here. This method was fully validated in human plasma according to FDA and EMA guidelines, and partially validated in mouse plasma, homogenates of mouse brain, kidney, liver, small intestine, spleen, and tissue culture medium. Palbociclib, an analog compound, was used as internal standard. A simple and fast sample pre-treatment by protein precipitation with acetonitrile was used, leading to efficient extraction of the analyte with recoveries between 95-100%. Chromatographic separation was achieved with a C18 analytical column and a gradient elution using 10 mM ammonium bicarbonate in water and 10 mM ammonium bicarbonate in water-methanol (1:9, v/v). This assay was selective, accurate, precise and linear in the concentration range of 1-1000 ng/mL. Moreover, samples above the upper limit of quantification can be integrally diluted up to 10-fold prior to analysis. The use of human plasma as a surrogate matrix to quantify milciclib in tissue culture medium and mouse matrices resulted in acceptable accuracy and precision, however tissue culture medium samples required a dilution with human plasma prior the pre-treatment. All performance parameters of the method complied with the acceptance criteria recommended by the guidelines, except for the carry-over, which was slightly above (22.9% of the lower limit of quantification) the recommended percentage (20%). Therefore, additional measures were taken to assure data integrity. Stability of milciclib in all matrices was evaluated, and in some matrices the analyte was unstable under the tested conditions. It is therefore recommended to keep these samples as briefly as possible at room temperature during the pre-treatment, and to store them at -70 °C to avoid analyte degradation. This method was successfully applied to support preclinical pharmacokinetic studies of milciclib.
- Published
- 2020
23. The role of drug efflux and uptake transporters ABCB1 (P-gp), ABCG2 (BCRP) and OATP1A/1B and of CYP3A4 in the pharmacokinetics of the CDK inhibitor milciclib
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Alejandra Martínez-Chávez, Jelle Broeders, Matthijs T. Tibben, Hilde Rosing, Maria C. Lebre, Alfred H. Schinkel, and Jos H. Beijnen
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Cmax ,Pharmaceutical Science ,Biological Availability ,02 engineering and technology ,Pharmacology ,030226 pharmacology & pharmacy ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Dogs ,Pharmacokinetics ,Cyclin-dependent kinase ,ATP Binding Cassette Transporter, Subfamily G, Member 2 ,Animals ,Cytochrome P-450 CYP3A ,Tissue Distribution ,Receptor ,Mice, Knockout ,biology ,Chemistry ,Kinase ,Brain ,021001 nanoscience & nanotechnology ,Neoplasm Proteins ,Pharmaceutical Preparations ,Trk receptor ,biology.protein ,Efflux ,0210 nano-technology ,CDK inhibitor - Abstract
The promising anticancer drug milciclib potently inhibits cyclin-dependent kinase (CDK) 2 and tropomyosin receptor kinase (TRK) A, and is currently in phase II clinical studies. To characterize factors affecting milciclib pharmacokinetics, we investigated whether milciclib is a substrate of the multidrug efflux and uptake transporters ABCB1 (P-gp), ABCG2 (BCRP), and OATP1A/1B, and the drug-metabolizing enzyme CYP3A, using genetically-modified mouse models and Madin-Darby Canine Kidney (MDCK-II) cells. In vitro, milciclib was transported by mAbcg2, and this was inhibited by the ABCG2 inhibitor Ko143. Upon oral administration of milciclib, its plasma exposure in Abcb1a/1b-/-, Abcg2-/-, and Abcb1a/1b;Abcg2-/- mice was similar to that found in wild-type mice. Milciclib showed good brain penetration even in wild-type mice (brain-to-plasma ratio of 1.2), but this was further increased by 5.2-fold when both Abcb1 and Abcg2 were ablated, and to a lesser extent in single Abcb1- or Abcg2-deficient mice. Oatp1a/1b deficiency had only a minor impact on the milciclib plasma AUC0-24h and Cmax. The milciclib AUC0-8h increased 1.9-fold in Cyp3a-/- mice but decreased only 1.3-fold upon overexpression of human CYP3A4. Thus, ABCB1 and ABCG2 cooperatively limit milciclib brain penetration. The low impact of OATP1 and CYP3A could be clinically favorable for milciclib, reducing the risks of unintended drug-drug interactions or interindividual variation in CYP3A4 activity.
- Published
- 2020
24. The histone and non-histone methyllysine reader activities of the UHRF1 tandem Tudor domain are dispensable for the propagation of aberrant DNA methylation patterning in cancer cells
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Varun Patel, Bailey M. Tibben, Stephen V. Frye, Rochelle L. Tiedemann, Robert M. Vaughan, Christine A. Berryhill, Krzysztof Krajewski, Cari A. Sagum, Caroline A. Foley, Brian D. Strahl, Ariana Kupai, Scott B. Rothbart, Mark T. Bedford, Kevin M. Shaw, Hope E. Eden, and Bradley M. Dickson
- Subjects
Tudor domain ,Methyltransferase ,lcsh:QH426-470 ,Ubiquitin-Protein Ligases ,Methylation ,Epigenesis, Genetic ,Histones ,03 medical and health sciences ,Methyllysine ,chemistry.chemical_compound ,Histone H3 ,0302 clinical medicine ,Genetics ,Humans ,Molecular Biology ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,DNA ligase ,biology ,Tudor Domain ,Research ,Lysine ,DNA Methylation ,HCT116 Cells ,Ubiquitin ligase ,Cell biology ,Gene Expression Regulation, Neoplastic ,Histone Code ,lcsh:Genetics ,Histone ,chemistry ,DNA methylation ,biology.protein ,CCAAT-Enhancer-Binding Proteins ,Protein Processing, Post-Translational ,030217 neurology & neurosurgery ,HeLa Cells - Abstract
The chromatin-binding E3 ubiquitin ligase ubiquitin-like with PHD and RING finger domains 1 (UHRF1) contributes to the maintenance of aberrant DNA methylation patterning in cancer cells through multivalent histone and DNA recognition. The tandem Tudor domain (TTD) of UHRF1 is well-characterized as a reader of lysine 9 di- and tri-methylation on histone H3 (H3K9me2/me3) and, more recently, lysine 126 di- and tri-methylation on DNA ligase 1 (LIG1K126me2/me3). However, the functional significance and selectivity of these interactions remain unclear. In this study, we used protein domain microarrays to search for additional readers of LIG1K126me2, the preferred methyl state bound by the UHRF1 TTD. We show that the UHRF1 TTD binds LIG1K126me2 with high affinity and selectivity compared to other known methyllysine readers. Notably, and unlike H3K9me2/me3, the UHRF1 plant homeodomain (PHD) and its N-terminal linker (L2) do not contribute to multivalent LIG1K126me2 recognition along with the TTD. To test the functional significance of this interaction, we designed a LIG1K126me2 cell-penetrating peptide (CPP). Consistent with LIG1 knockdown, uptake of the CPP had no significant effect on the propagation of DNA methylation patterning across the genomes of bulk populations from high-resolution analysis of several cancer cell lines. Further, we did not detect significant changes in DNA methylation patterning from bulk cell populations after chemical or genetic disruption of lysine methyltransferase activity associated with LIG1K126me2 and H3K9me2. Collectively, these studies identify UHRF1 as a selective reader of LIG1K126me2 in vitro and further implicate the histone and non-histone methyllysine reader activity of the UHRF1 TTD as a dispensable domain function for cancer cell DNA methylation maintenance.
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- 2020
25. Toxicological analysis of azide and cyanide for azide intoxications using gas chromatography
- Author
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Hilde Rosing, Douwe Dekker, Alwin D. R. Huitema, Dylan W. de Lange, Jos H. Beijnen, M.A.C. Bruin, Nikkie Venekamp, and Matthijs M. Tibben
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Adult ,Azides ,CYANIDE EXPOSURE ,Chromatography, Gas ,Cyanide ,gas chromatography ,Hydrogen cyanide ,chemistry.chemical_element ,Urine ,030226 pharmacology & pharmacy ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Propionic anhydride ,azide ,Humans ,Clinical Toxicology ,Pharmacology ,cyanide ,Chromatography ,Cyanides ,nitrogen phosphorous detector ,General Medicine ,Nitrogen ,chemistry ,Female ,Original Article ,Azide ,Gas chromatography ,ORIGINAL ARTICLES ,030217 neurology & neurosurgery ,toxicology - Abstract
Azide is a highly toxic chemical agent to human being. Accidental, but also intentional exposure to azide occurs. To be able to confirm azide ingestion, we developed a method to identify and quantify azide in biological matrices. Cyanide was included in the method to evaluate suggested in vivo production of cyanide after azide ingestion. Azide in biological matrices was first derivatized by propionic anhydride to form propionyl azide. Simultaneously, cyanide was converted into hydrogen cyanide. After thermal rearrangement of propionyl azide, ethyl isocyanate was formed, separated together with hydrogen cyanide by gas chromatography (GC) and detected using a nitrogen phosphorous detector (NPD). The method was linear from 1.0‐100 µg/mL for both analytes, and azide was stable in human plasma at −20°C for at least 49 days. Azide was measured in the gastric content of two cases of suspected azide ingestion (case 1:1.2 mg/mL, case 2:1.5 mg/mL). Cyanide was only identified in the gastric content of case 1 (approximately 1.4 µg/mL). Furthermore, azide was quantified in plasma (19 µg/mL), serum (24 µg/mL), cell pellet (21 µg/mL) and urine (3.0 µg/mL) of case 2. This method can be used to confirm azide and cyanide exposure, and azide concentrations can be quantified in several biological matrices.
- Published
- 2020
26. [Don't be guided purely by numbers: false increased TSH values due to analytical interference]
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N E, Tibben, J A P, Bons, S A A, van den Berg, J, Huisman, and J G, Krabbe
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Male ,Thyroxine ,Thyrotoxicosis ,Hypothyroidism ,Reference Values ,Immunoglobulin G ,Humans ,Thyrotropin ,False Positive Reactions ,Middle Aged ,Thyroid Function Tests ,Hyperthyroidism - Abstract
Physicians are often guided by laboratory values. When a clinical presentation does not match laboratory values, one must consider the possibility that these values may be falsely increased or decreased. A common cause is analytical interference.A 57-year-old male, presenting with fatigue and palpitations, had high TSH and normal FT4 values. Although there were no fitting clinical symptoms for these values, the patient was treated with levothyroxine assuming he had subclinical hypothyroidism. TSH levels remained high, however, whereas FT4 levels increased and the patient developed thyrotoxicosis. Eventually, it was discovered that the TSH was falsely elevated.The patient turned out to have macro TSH, where TSH forms conjunctions with IgG into larger molecules. These conjugates cause a rarely occurring interference during laboratory analysis, resulting in a falsely increased TSH value.
- Published
- 2020
27. The Position of Neuromuscular Patients in Shared Decision Making. Report from the 235th ENMC Workshop: Milan, Italy, January 19-20, 2018
- Author
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Mike Snape, Aad Tibben, Baziel G.M. van Engelen, Mencia de Lemus, Hanns Lochmüller, Alexandra Breukel, Holly L. Peay, Nathalie Bere, Ellen Sterrenburg, George W. Padberg, Raffaella Willmann, Erik Landfeldt, Ingeborg Meijer, Lucia Monaco, Anna Ambrosini, Guus Schrijvers, Elena S. Mazzone, Mats G. Hansson, and Anne Lennox
- Subjects
0301 basic medicine ,medicine.medical_specialty ,business.industry ,Psychological intervention ,Context (language use) ,Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3] ,Biobank ,Clinical trial ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Quality of life (healthcare) ,Neurology ,Family medicine ,Health care ,medicine ,Observational study ,Neurology (clinical) ,Patient participation ,Psychology ,business ,030217 neurology & neurosurgery - Abstract
Contains fulltext : 207092.pdf (Publisher’s version ) (Closed access) In the era of patient-centered medicine, shared decision-making (SDM) - in which healthcare professionals and patients exchange information and preferences and jointly reach a decision - has emerged as the gold standard model for the provision of formal healthcare. Indeed, in many geographical settings, patients are frequently invited to participate in choices concerning the design and delivery of their medical management. From a clinical perspective, benefits of this type of patient involvement encompass, for example, enhanced treatment satisfaction, improved medical compliance, better health outcomes, and maintained or promoted quality of life. Yet, although the theory and enactment of SDM in healthcare are well-described in the literature [1-3], comparatively less attention has been devoted to contextualizing questions relating to if, when, and how to include patients in decisions within medical research. In this context, patient involvement would be expected to be potentially relevant for and applicable to a wide range of activities and processes, from the identification of research priorities and development of grant applications, to the design of patient information and consent procedures, formulation of interventions, identification and recruitment of study sample populations, feasibility of a clinical trial, identification, selection, and specification of endpoints and outcomes in clinical trials and observational studies, data collection and analysis, and dissemination of results. To this end, 45 clinicians, healthcare professionals, researchers, patients, caregivers, and representatives from regulatory authorities and pharmaceutical companies from 15 different countries met to discuss the level of involvement of patients with neuromuscular diseases, specifically in the following settings of medical research for neuromuscular diseases: i) registries and biobanks; ii) clinical trials; and iii) regulatory processes. In this report, we present summaries of the talks that were given during the workshop, as well as discussion outcomes from the three topic areas listed above.
- Published
- 2019
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28. ABCB1 and ABCG2 limit brain penetration and, together with CYP3A4, total plasma exposure of abemaciclib and its active metabolites
- Author
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Nancy H.C. Loos, Alejandra Martínez-Chávez, Hilde Rosing, Alfred H. Schinkel, Jos H. Beijnen, Matthijs M. Tibben, and Maria C. Lebre
- Subjects
CYP3A ,Cmax ,Aminopyridines ,Pharmacology ,Madin Darby Canine Kidney Cells ,Mice ,Dogs ,Pharmacokinetics ,Cyclin-dependent kinase ,Oral administration ,medicine ,ATP Binding Cassette Transporter, Subfamily G, Member 2 ,Animals ,Cytochrome P-450 CYP3A ,Humans ,ATP Binding Cassette Transporter, Subfamily B, Member 1 ,Active metabolite ,Mice, Knockout ,biology ,Chemistry ,Brain ,Small intestine ,Neoplasm Proteins ,medicine.anatomical_structure ,Pharmaceutical Preparations ,Toxicity ,biology.protein ,Benzimidazoles - Abstract
Abemaciclib is the third cyclin-dependent kinase (CDK) 4/6 inhibitor approved for the treatment of breast cancer and currently under investigation for other malignancies, including brain cancer. Primarily CYP3A4 metabolizes abemaciclib, forming three active metabolites (M2, M20 and M18) that are likely relevant for abemaciclib efficacy and toxicity. We investigated the impact of ABCB1 (P-gp), ABCG2 (BCRP) and CYP3A on the pharmacokinetics and tissue distribution of abemaciclib and its metabolites using genetically modified mice. In vitro, abemaciclib was efficiently transported by hABCB1 and mAbcg2, and slightly by hABCG2, but the active metabolites were transported even better. Upon oral administration of 10mg/kg abemaciclib, absence of Abcg2 and especially Abcb1a/1b significantly increased the plasma AUC0-24h and Cmax of M2 and M18. Furthermore, the relative brain penetration of abemaciclib, M2 and M20 was dramatically increased by 25-, 4- and 60-fold, respectively, in Abcb1a/1b;Abcg2-/- mice, and to a lesser extent in single Abcb1a/1b- or Abcg2-deficient mice. The recovery of all active compounds in the small intestine content was profoundly reduced in Abcb1a/1b;Abcg2-/- mice, with smaller effects in single Abcb1a/1b-/- and Abcg2-/- mice. Our results indicate that Abcb1a/1b and Abcg2 cooperatively and profoundly limit the brain penetration of abemaciclib and its active metabolites, and likely also participate in their hepatobiliary or direct intestinal elimination. Moreover, transgenic human CYP3A4 drastically reduced the abemaciclib plasma AUC0-24h and Cmax by 7.5- and 5.6-fold, respectively, relative to Cyp3a-/- mice. These insights may help to optimize the clinical development of abemaciclib, especially for the treatment of brain malignancies.
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- 2022
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29. Offering a choice between NIPT and invasive PND in prenatal genetic counseling: The impact of clinician characteristics on patients’ test uptake
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Arend Tibben, Sanne van der Steen, Jan J. V. Busschbach, Iris M. Bakkeren, Marike Polak, Samantha Riedijk, Diewertje Houtman, Robert-Jan H. Galjaard, Clinical Genetics, Research Methods and Techniques, and Psychiatry
- Subjects
0301 basic medicine ,Adult ,Male ,medicine.medical_specialty ,Genetic counseling ,MEDLINE ,Prenatal diagnosis ,Genetic Counseling ,030105 genetics & heredity ,Affect (psychology) ,Choice Behavior ,Article ,03 medical and health sciences ,0302 clinical medicine ,Pregnancy ,Physicians ,Prenatal Diagnosis ,Genetics ,medicine ,Humans ,In patient ,Genetic Testing ,Genetics (clinical) ,030219 obstetrics & reproductive medicine ,business.industry ,Patient Preference ,Middle Aged ,medicine.disease ,Preference ,Test (assessment) ,Family medicine ,Female ,business - Abstract
Testing options for pregnant women at increased risk of common aneuploidies are non-invasive prenatal testing (NIPT) and invasive prenatal diagnosis (PND). Clinicians are challenged to comprehensively discuss the complex information in a patient-centered and non-directive manner, to allow for patients’ informed decision-making. This study explored the information-centeredness, patient-centeredness, and level of non-directivity of different clinicians and examined group differences between their patients. First, semi-structured interviews with four senior obstetricians and one senior nurse were held regarding their information provision, their adaptation of a patient-centered attitude, and their practice of non-directivity. Interviews were transcribed verbatim and rated by four independent researchers. Secondly, 181 pregnant women were included in the study, of whom 82% opted for NIPT and 18% chose PND. Between clinicians, we assessed the distribution of choice ratios, patients’ impression of clinicians’ test preferences, and patients’ knowledge scores. The results indicate that clinicians do not differ in their information-centeredness, but do differ in their patient-centeredness and their level of non-directivity. Significant differences in patients’ NIPT/PND ratios were observed between clinicians, with the largest difference being 35 vs. 4% opting for invasive PND. Between 9 and 22% of the patients had an impression of their clinician’s preference and chose in accordance with this preference. Patients’ overall knowledge scores did not differ across clinicians. In conclusion, the differences in NIPT/PND ratios between clinicians indicate that clinicians’ differing counseling approaches affect the choices their patients make. The interviews indicate a possible framing effect which may unintentionally steer the decision-making process.
- Published
- 2018
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30. Review of cybersecurity frameworks: context and shared concepts
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William Tibben, Riza Azmi, and Khin Than Win
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021110 strategic, defence & security studies ,0211 other engineering and technologies ,Context (language use) ,060301 applied ethics ,06 humanities and the arts ,02 engineering and technology ,Sociology ,0603 philosophy, ethics and religion ,Resilience (network) ,Computer security ,computer.software_genre ,computer - Abstract
In an effort to develop strong cyber resilience, international organisations, academic institutions, corporations and countries have been actively working to develop cybersecurity frameworks (CSFs)...
- Published
- 2018
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31. Barriers and facilitators to clinical trial participation among parents of children with pediatric neuromuscular disorders
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Holly L. Peay, Jill Jarecki, Aad Tibben, Barbara B. Biesecker, Kendall L. Umstead, Diana M. Escolar, and Benjamin S. Wilfond
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Male ,Parents ,Duchenne muscular dystrophy ,Health Knowledge, Attitudes, Practice ,Pediatrics ,medicine.medical_specialty ,Spinal Muscular Atrophies of Childhood ,Article ,Unmet needs ,03 medical and health sciences ,Clinical trials ,0302 clinical medicine ,Professional-Family Relations ,Surveys and Questionnaires ,030225 pediatrics ,Humans ,participation ,Medicine ,Child ,Randomized Controlled Trials as Topic ,spinal muscular atrophy ,Pharmacology ,business.industry ,Patient Selection ,Communication Barriers ,General Medicine ,Spinal muscular atrophy ,medicine.disease ,Muscular Dystrophy, Duchenne ,Clinical trial ,Logistic Models ,recruitment ,Becker muscular dystrophy ,Female ,business ,030217 neurology & neurosurgery ,Rare disease - Abstract
Background/aims: Pediatric rare disease presents a challenging situation of high unmet need and a limited pool of potential clinical trial participants. Understanding perspectives of parents of children who have not participated in trials may facilitate approaches to optimize participation rates. The objective of this study was to explore factors associated with parental interest in enrolling children with pediatric neuromuscular disorders in clinical trials. Methods: Parents of individuals with Duchenne or Becker muscular dystrophy and spinal muscular atrophy were recruited through advocacy organizations, a registry, and clinics. These parents ( N = 203) completed a questionnaire including assessments of barriers and facilitators to clinical trial participation, parents’ interest in trial participation, and their perceptions of others’ views about participation in a clinical trial. Results: Trial interest in participating parents was high (64% combined group). The most highly endorsed barrier to participation was the possibility of receiving placebo, followed by not having enough information on risks and trial procedures. Compared to parents of children with Duchenne or Becker muscular dystrophy, parents of children with spinal muscular atrophy endorsed significantly more information and knowledge barriers. The greatest facilitators of participation were (1) confidence in improving disease understanding and (2) guarantee to receive the treatment after a successful trial. A logistic regression model, χ2 (4, n = 188) = 80.64, p Conclusion: We found high parental interest in pediatric neuromuscular trials that was tempered by concerns about the potential for randomization to a placebo arm. Participants perceived that their trial participation would be facilitated by additional education and guidance from their clinicians. Yet, intentions were negatively associated with frequency of provider communication, perhaps reflecting waning parental interest with a greater understanding of limitations in trial access, increased sophistication in their understanding of trial design, and appreciation of potential burden. To support parents’ informed decisions, it is important to educate them to evaluate the quality of research, as well as providing lay information explaining the use of placebo, trial processes, and potential barriers to long-term drug access. Our findings should inform the development of targeted educational content, clinician training, and decision support tools.
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- 2018
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32. Determination of the absolute oral bioavailability of niraparib by simultaneous administration of a 14C-microtracer and therapeutic dose in cancer patients
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Zhi-Yi Zhang, Matthijs M. Tibben, M. Sanghvi, V. Kansra, A. Gebretensae, Hilde Rosing, Jos H. Beijnen, L. van Andel, J. H. M. Schellens, and L. Hughes
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Pharmacology ,Cancer Research ,Chemotherapy ,business.industry ,medicine.medical_treatment ,Cancer ,Toxicology ,Placebo ,medicine.disease ,030226 pharmacology & pharmacy ,High-performance liquid chromatography ,Bioavailability ,Clinical trial ,03 medical and health sciences ,0302 clinical medicine ,Therapeutic index ,Oncology ,Pharmacokinetics ,030220 oncology & carcinogenesis ,Medicine ,Pharmacology (medical) ,business - Abstract
Niraparib (Zejula™) is a poly(ADP-ribose) polymerase inhibitor recently approved by the US Food and Drug Administration for the maintenance treatment of patients with recurrent platinum-sensitive epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to platinum-based chemotherapy. The pivotal phase III clinical trial has shown improved progression-free survival in patients receiving niraparib compared with those receiving placebo. Since niraparib is administered orally, it is of interest to investigate the oral bioavailability (F po) of this novel compound, which is the aim of this study. Six patients received an oral therapeutic dose of 300 mg niraparib, followed by a 15-min intravenous infusion of 100 µg 14C-niraparib with a radioactivity of approximately 100 nCi. The niraparib therapeutic dose was measured in plasma using a validated liquid chromatography–tandem mass spectrometry method, whereas the total 14C-radioactivity and 14C-niraparib plasma levels were measured by accelerator mass spectrometry and a validated high performance liquid chromatography assay with AMS. The F po of niraparib was determined to be 72.7% in humans.
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- 2017
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33. Human mass balance study and metabolite profiling of 14C-niraparib, a novel poly(ADP-Ribose) polymerase (PARP)-1 and PARP-2 inhibitor, in patients with advanced cancer
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van Andel, Lotte, Zhang, Z, Lu, S., Kansra, V, Agarwal, S., Hughes, L., Tibben, M., Gebretensae, A., Lucas, L., Hillebrand, Michel J X, Rosing, H., Schellens, J H M, Beijnen, J H, Sub Inorganic Chemistry and Catalysis, Afd Pharmacoepi & Clinical Pharmacology, Pharmacoepidemiology and Clinical Pharmacology, Sub Inorganic Chemistry and Catalysis, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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0301 basic medicine ,Adult ,Indazoles ,Metabolite ,Poly (ADP-Ribose) Polymerase-1 ,Breast Neoplasms ,Urine ,Niraparib ,Pharmacology ,Mass balance ,Poly(ADP-ribose) Polymerase Inhibitors ,Tandem mass spectrometry ,Poly (ADP-Ribose) Polymerase Inhibitor ,Excretion ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Piperidines ,Phase I Studies ,Radiolabelled ,Metabolites ,Humans ,Pharmacology (medical) ,Carbon Radioisotopes ,ADME ,Whole blood ,Aged ,Ovarian Neoplasms ,Middle Aged ,Prognosis ,030104 developmental biology ,Oncology ,chemistry ,Biochemistry ,030220 oncology & carcinogenesis ,Female ,Poly(ADP-ribose) Polymerases ,Glucuronide ,Colorectal Neoplasms ,TRA ,Follow-Up Studies - Abstract
SummaryNiraparib is an investigational oral, once daily, selective poly(ADP-Ribose) polymerase (PARP)-1 and PARP-2 inhibitor. In the pivotal Phase 3 NOVA/ENGOT/OV16 study, niraparib met its primary endpoint of improving progression-free survival (PFS) for adult patients with recurrent, platinum sensitive, ovarian, fallopian tube, or primary peritoneal cancer in complete or partial response to platinum-based chemotherapy. Significant improvements in PFS were seen in all patient cohorts regardless of biomarker status. This study evaluates the absorption, metabolism and excretion (AME) of 14C–niraparib, administered to six patients as a single oral dose of 300 mg with a radioactivity of 100 μCi. Total radioactivity (TRA) in whole blood, plasma, urine and faeces was measured using liquid scintillation counting (LSC) to obtain the mass balance of niraparib. Moreover, metabolite profiling was performed on selected plasma, urine and faeces samples using liquid chromatography – tandem mass spectrometry (LC-MS/MS) coupled to off-line LSC. Mean TRA recovered over 504 h was 47.5% in urine and 38.8% in faeces, indicating that both renal and hepatic pathways are comparably involved in excretion of niraparib and its metabolites. The elimination of 14C–radioactivity was slow, with t1/2 in plasma on average 92.5 h. Oral absorption of 14C–niraparib was rapid, with niraparib concentrations peaking at 2.49 h, and reaching a mean maximum concentration of 540 ng/mL. Two major metabolites were found: the known metabolite M1 (amide hydrolysed niraparib) and the glucuronide of M1. Based on this study it was shown that niraparib undergoes hydrolytic, and conjugative metabolic conversions, with the oxidative pathway being minimal.
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- 2017
34. Additional file 4 of The histone and non-histone methyllysine reader activities of the UHRF1 tandem Tudor domain are dispensable for the propagation of aberrant DNA methylation patterning in cancer cells
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Vaughan, Robert M., Kupai, Ariana, Foley, Caroline A., Sagum, Cari A., Tibben, Bailey M., Eden, Hope E., Tiedemann, Rochelle L., Berryhill, Christine A., Varun Patel, Shaw, Kevin M., Krajewski, Krzysztof, Strahl, Brian D., Bedford, Mark T., Frye, Stephen V., Dickson, Bradley M., and Rothbart, Scott B.
- Abstract
Additional file 4: Figure S2. A LIG1K126me2 cell penetrating peptide has no significant effects on HCT116 cell DNA methylation. (A) Fluorescence microscopy of HCT116 cells after 5-h incubation with control solvent (water) or with FAM-LIG1K126me2-CPP. (B) Infinium MethylationEPIC BeadChip analysis of HCT116 cells (beta values: 0, unmethylated; 1, methylated) after 7 days of incubation with water (control) or LIG1K126me2-CPP peptide at 20 µM. Scatter plots with density for all probes (left), those that had beta value > 0.8 in control cells (middle), and distribution of ∆β (right) between control and LIG1K126me2-CPP treated cells for probes that were > 0.8 in control cells (n).
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- 2020
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35. Additional file 1 of The histone and non-histone methyllysine reader activities of the UHRF1 tandem Tudor domain are dispensable for the propagation of aberrant DNA methylation patterning in cancer cells
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Vaughan, Robert M., Kupai, Ariana, Foley, Caroline A., Sagum, Cari A., Tibben, Bailey M., Eden, Hope E., Tiedemann, Rochelle L., Berryhill, Christine A., Varun Patel, Shaw, Kevin M., Krajewski, Krzysztof, Strahl, Brian D., Bedford, Mark T., Frye, Stephen V., Dickson, Bradley M., and Rothbart, Scott B.
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ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION - Abstract
Additional file 1: Figure S1. Methyl reader domain array layout corresponding to images in Fig. 1a.
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- 2020
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36. Revisiting 'Cyber' Definition
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Ima Apriany, William Tibben, Kautsarina Kautsarina, and Riza Azmi
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Cognitive science ,021110 strategic, defence & security studies ,020209 energy ,Political science ,0211 other engineering and technologies ,0202 electrical engineering, electronic engineering, information engineering ,Context (language use) ,02 engineering and technology ,Domain (software engineering) - Abstract
The term “cyber” has been used widely in recent times and in particular in the context of security. Given the wide usage in formal and informal contexts, it is possible that its origin and true meaning will not be fully appreciated and understood. The Cooperative Cyber Defense Center of Excellence (CCDCE) has made available a range of various definitions. The term cyber has become very prevalent and appeared in many national and international statements and in some cases having contradictory interpretations. This chapter aims to revisit the term cyber by walking through its use in various contexts. It starts from the context of the word's origin; what is really entailed in the cyber world; and definitions portraying the understanding of the term from academics, national, and international organizations. Finally, the chapter combines the different interpretations into a single abridged definition from the various accumulated perspectives.
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- 2020
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37. P-glycoprotein (MDR1/ABCB1) controls brain accumulation and intestinal disposition of the novel TGF-β signaling pathway inhibitor galunisertib
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Li, Wenlong, Tibben, Matthijs, Wang, Yaogeng, Lebre, Maria C, Rosing, Hilde, Beijnen, Jos H, Schinkel, Alfred H, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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brain accumulation ,galunisertib ,oral availability ,intestinal disposition ,cytochrome P450-3A ,P-glycoprotein ,Oatp1a/1b - Abstract
Galunisertib (LY2157299), a promising small-molecule inhibitor of the transforming growth factor-beta (TGF-β) receptor, is currently in mono- and combination therapy trials for various cancers including glioblastoma, hepatocellular carcinoma and breast cancer. Using genetically modified mouse models, we investigated the roles of the multidrug efflux transporters ABCB1 and ABCG2, the OATP1A/1B uptake transporters and the drug-metabolizing CYP3A complex in galunisertib pharmacokinetics. In vitro, galunisertib was vigorously transported by human ABCB1, and moderately by mouse Abcg2. Orally administered galunisertib (20 mg/kg) was very rapidly absorbed. Galunisertib brain-to-plasma ratios were increased by ~24-fold in Abcb1a/1b-/- and Abcb1a/1b;Abcg2-/- mice compared to wild-type mice, but not in single Abcg2-/- mice, whereas galunisertib oral availability was not markedly affected. However, recovery of galunisertib in the small intestinal lumen was strongly reduced in Abcb1a/1b-/- and Abcb1a/1b;Abcg2-/- mice. Oral coadministration of the ABCB1/ABCG2 inhibitor elacridar boosted galunisertib brain accumulation in wild-type mice to equal the levels seen in Abcb1a/1b;Abcg2-/- mice. Oatp1a/1b deficiency did not alter oral galunisertib pharmacokinetics or liver distribution. Cyp3a-/- mice showed a 1.9-fold higher plasma AUC0-1 hr than wild-type mice, but this difference disappeared over 8 hr. Also, transgenic human CYP3A4 overexpression did not significantly alter oral galunisertib pharmacokinetics. Abcb1 thus markedly restricts galunisertib brain penetration and affects its intestinal disposition, possibly through biliary excretion. Elacridar coadministration could fully inhibit both processes, without causing acute toxicity. Moreover, mouse Cyp3a, but not human CYP3A4, may eliminate galunisertib at high plasma concentrations. These insights may help to guide the further clinical development and application of galunisertib.
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- 2020
38. Vaar niet alleen op een getal: vals verhoogde TSH-waarde door interferentie bij analyse = Don't be guided purely by numbers: false increased TSH values due to analytical interference
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Tibben, NE, Bons, JAP, van den Berg, Sjoerd, Huisman, J, Krabbe, JG, and Clinical Chemistry
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- 2020
39. Liquid chromatography-tandem mass spectrometric assay for the quantification of galunisertib in human plasma and the application in a pre-clinical study
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Tibben, M M, Huijberts, S, Li, W, Schinkel, A H, Gebretensae, A, Rosing, H, Beijnen, J H, Afd Pharmacoepi & Clinical Pharmacology, Pharmacoepidemiology and Clinical Pharmacology, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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Male ,Analyte ,Bioanalysis ,Clinical Biochemistry ,Administration, Oral ,Pharmaceutical Science ,Sensitivity and Specificity ,01 natural sciences ,Analytical Chemistry ,Matrix (chemical analysis) ,Mice ,Pharmacokinetics ,LC–MS/MS ,Tandem Mass Spectrometry ,Transforming Growth Factor beta ,Drug Discovery ,Animals ,Humans ,Galunisertib ,Protein precipitation ,Protein Kinase Inhibitors ,Chromatography, High Pressure Liquid ,Spectroscopy ,Chromatography ,Tandem ,human plasma ,010405 organic chemistry ,Chemistry ,010401 analytical chemistry ,Reproducibility of Results ,assay ,mouse plasma ,quantification ,0104 chemical sciences ,Triple quadrupole mass spectrometer ,Quinolines ,Pyrazoles ,Galunisertb ,Drug Screening Assays, Antitumor - Abstract
Galunisertib is an anti-cancer drug currently evaluated in phase I and II clinical trials. This study describes the development and validation of a bioanalytical assay to quantify galunisertib in human plasma using HPLC-MS/MS. Stable isotope labelled galunisertib was added as internal standard and the analyte and internal standard were extracted from the matrix by protein precipitation using acetonitrile-methanol (50:50, v/v). Final extracts were injected onto a C18 column, gradient elution was applied for chromatographic separation and detection was performed using a triple quadrupole mass spectrometer operating in the positive ion mode. The assay was linear over the range 0.05-10 ng/mL, with acceptable accuracy (bias ranging from -6.1 to 3.1%) and precision (below 5.7% C.V.) values. The applicability of the assay was demonstrated in a pharmacokinetic experiment in mice.
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- 2019
40. P-glycoprotein Limits Ribociclib Brain Exposure and CYP3A4 Restricts Its Oral Bioavailability
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Martínez-Chávez, Alejandra, van Hoppe, Stéphanie, Rosing, Hilde, Lebre, Maria C, Tibben, Matthijs, Beijnen, Jos H, Schinkel, Alfred H, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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CYP3A4 ,BRCP ,P-gp ,ribociclib ,CDK4/6 inhibitor ,brain penetration - Abstract
Ribociclib is a CDK4/6 inhibitor recently approved for the treatment of some types of breast cancer in combination with an aromatase inhibitor. It is currently investigated in the clinic to treat other malignancies, including brain tumors. Using in vitro and genetically modified mouse models, we investigated the effect of the multidrug efflux transporters ABCB1 and ABCG2, and the drug-metabolizing CYP3A enzymes on ribociclib pharmacokinetics and tissue distribution. In vitro, ribociclib was avidly transported by human ABCB1, but not by human ABCG2 and only modestly by mouse Abcg2. Upon oral administration at 20 mg/kg, the plasma AUC0-24h of ribociclib was increased by 2.3-fold, and its terminal elimination was delayed in Abcb1a/1b -/- ;Abcg2 -/- compared to wild-type mice. The brain-to-plasma ratios of ribociclib were increased by at least 23-fold relative to wild-type mice in Abcb1a/1b -/- ;Abcg2 -/- and Abc1a/1b -/- mice, but not noticeably in Abcg2 -/- mice. Oral coadministration of elacridar, an ABCB1 and ABCG2 inhibitor, increased the brain penetration of ribociclib in wild-type mice to the same level as seen in Abcb1a/1b -/- ;Abcg2 -/- mice. Plasma exposure of ribociclib further decreased by 3.8-fold when transgenic human CYP3A4 was overexpressed in Cyp3a-deficient mice. Ribociclib penetration into the brain is thus drastically limited by ABCB1 in the blood-brain barrier, but coadministration of elacridar can fully reverse this process. Moreover, human CYP3A4 can extensively metabolize ribociclib and strongly restrict its oral bioavailability. The insights obtained from this study may be useful to further optimize the clinical application of ribociclib, especially for the treatment of (metastatic) brain tumors.
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- 2019
41. P-glycoprotein Limits Ribociclib Brain Exposure and CYP3A4 Restricts Its Oral Bioavailability
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Martínez-Chávez, Alejandra, van Hoppe, Stéphanie, Rosing, Hilde, Lebre, Maria C, Tibben, Matthijs, Beijnen, Jos H, Schinkel, Alfred H, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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Genetically modified mouse ,ATP Binding Cassette Transporter, Subfamily B ,CYP3A4 ,Abcg2 ,CYP3A ,Transgene ,Administration, Oral ,Aminopyridines ,Biological Availability ,Pharmaceutical Science ,02 engineering and technology ,Pharmacology ,030226 pharmacology & pharmacy ,CDK4/6 inhibitor ,brain penetration ,Madin Darby Canine Kidney Cells ,Mice ,03 medical and health sciences ,Dogs ,0302 clinical medicine ,Pharmacokinetics ,Transduction, Genetic ,Oral administration ,Tetrahydroisoquinolines ,Drug Discovery ,ATP Binding Cassette Transporter, Subfamily G, Member 2 ,Animals ,Cytochrome P-450 CYP3A ,Humans ,Tissue Distribution ,ATP Binding Cassette Transporter, Subfamily B, Member 1 ,ribociclib ,P-glycoprotein ,Mice, Knockout ,biology ,Chemistry ,Biological Transport ,021001 nanoscience & nanotechnology ,Neoplasm Proteins ,Bioavailability ,Blood-Brain Barrier ,Purines ,biology.protein ,BRCP ,Acridines ,Molecular Medicine ,P-gp ,Female ,0210 nano-technology - Abstract
Ribociclib is a CDK4/6 inhibitor recently approved for the treatment of some types of breast cancer in combination with an aromatase inhibitor. It is currently investigated in the clinic to treat other malignancies, including brain tumors. Using in vitro and genetically modified mouse models, we investigated the effect of the multidrug efflux transporters ABCB1 and ABCG2, and the drug-metabolizing CYP3A enzymes on ribociclib pharmacokinetics and tissue distribution. In vitro, ribociclib was avidly transported by human ABCB1, but not by human ABCG2 and only modestly by mouse Abcg2. Upon oral administration at 20 mg/kg, the plasma AUC0-24h of ribociclib was increased by 2.3-fold, and its terminal elimination was delayed in Abcb1a/1b -/- ;Abcg2 -/- compared to wild-type mice. The brain-to-plasma ratios of ribociclib were increased by at least 23-fold relative to wild-type mice in Abcb1a/1b -/- ;Abcg2 -/- and Abc1a/1b -/- mice, but not noticeably in Abcg2 -/- mice. Oral coadministration of elacridar, an ABCB1 and ABCG2 inhibitor, increased the brain penetration of ribociclib in wild-type mice to the same level as seen in Abcb1a/1b -/- ;Abcg2 -/- mice. Plasma exposure of ribociclib further decreased by 3.8-fold when transgenic human CYP3A4 was overexpressed in Cyp3a-deficient mice. Ribociclib penetration into the brain is thus drastically limited by ABCB1 in the blood-brain barrier, but coadministration of elacridar can fully reverse this process. Moreover, human CYP3A4 can extensively metabolize ribociclib and strongly restrict its oral bioavailability. The insights obtained from this study may be useful to further optimize the clinical application of ribociclib, especially for the treatment of (metastatic) brain tumors.
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- 2019
42. Development and validation of a bioanalytical method for the quantification of the CDK4/6 inhibitors abemaciclib, palbociclib, and ribociclib in human and mouse matrices using liquid chromatography-tandem mass spectrometry
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Martínez-Chávez, Alejandra, Rosing, Hilde, Hillebrand, Michel, Tibben, Matthijs, Schinkel, Alfred H, Beijnen, Jos H, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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Cyclin-Dependent Kinase 4/antagonists & inhibitors ,Pyridines/analysis ,Benzimidazoles/analysis ,Mice ,Purines/analysis ,Animals ,Chromatography, Liquid/methods ,Humans ,Aminopyridines/analysis ,Piperazines/analysis ,Cyclin-Dependent Kinase 6/antagonists & inhibitors ,Protein Kinase Inhibitors/analysis ,Tandem Mass Spectrometry/methods - Abstract
A novel method was developed and validated for the quantification of the three approved CDK4/6 inhibitors (abemaciclib, palbociclib, and ribociclib) in both human and mouse plasma and mouse tissue homogenates (liver, kidney, spleen, brain, and small intestine) using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). For all matrices, pretreatment was performed using 50 μL of sample by protein precipitation with acetonitrile, followed by dilution of the supernatant. Chromatographic separation of the analytes was done on a C18 column using gradient elution. A full validation was performed for human plasma, while a partial validation was executed for mouse plasma and mouse tissue homogenates. The method was linear in the calibration range from 2 to 200 ng/mL, with a correlation coefficient (r) ≥0.996 for each analyte. For both human and mouse plasma, the accuracy and precision were within ±15% and ≤15%, respectively, for all concentrations, except for the lower limit of quantification, where they were within ±20% and ≤20%, respectively. A fit-for-purpose strategy was followed for tissue homogenates, and the accuracy and precision were within ±20% and ≤20%, respectively, for all concentrations. Stability of all analytes in all matrices at different processing and storage conditions was tested; ribociclib and palbociclib were unstable in most tissue homogenates and conditions were modified to increase the stability. The method was successfully applied for the analysis of mouse samples from preclinical studies. A new ribociclib metabolite was detected in mouse plasma samples with the same m/z transition as the parent drug.
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- 2019
43. 'be an ambassador for change that you would like to see':A call to action to all stakeholders for co-creation in healthcare and medical research to improve quality of life of people with a neuromuscular disease
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Ingeborg Meijer, Hanns Lochmüller, Ros Quinlivan, George W. Padberg, Aad Tibben, Alexandre Méjat, Anna Ambrosini, Alexandra Breukel, Guus Schrijvers, Valeria A. Sansone, Raffaella Willmann, Michal Rataj, Maarten de Wit, Ellen Sterrenburg, Goemans, Nathalie, Ethics, Law & Medical humanities, and Schara, Ulrike (Beitragende*r)
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0301 basic medicine ,PATIENT PARTICIPATION ,INVOLVEMENT ,Biomedical Research ,Decision Making ,Medizin ,Patient engagement ,lcsh:Medicine ,030105 genetics & heredity ,Research & Experimental Medicine ,Marketing authorization ,DIAGNOSIS ,DUCHENNE MUSCULAR-DYSTROPHY ,03 medical and health sciences ,0302 clinical medicine ,Cultural diversity ,Health care ,Co-creation ,MANAGEMENT ,Humans ,Pharmacology (medical) ,Patient involvement ,Genetics (clinical) ,Genetics & Heredity ,Medical education ,Science & Technology ,business.industry ,RESEARCH-AND-DEVELOPMENT ,Research ,lcsh:R ,Healthcare ,General Medicine ,Biobank ,Call to action ,MODEL ,Neuromuscular diseases ,Medicine, Research & Experimental ,General partnership ,Quality of Life ,Patient-reported outcome ,Psychology ,business ,SHARED DECISION-MAKING ,RARE DISEASES ,FOLLOW-UP ,Life Sciences & Biomedicine ,030217 neurology & neurosurgery - Abstract
BACKGROUND: Patient and public involvement for co-creation is increasingly recognized as a valuable strategy to develop healthcare research targeting patients' real needs. However, its practical implementation is not as advanced and unanimously accepted as it could be, due to cultural differences and complexities of managing healthcare programs and clinical studies, especially in the rare disease field. MAIN BODY: The European Neuromuscular Centre, a European foundation of patient organizations, involved its key stakeholders in a special workshop to investigate the position of the neuromuscular patient community with respect to healthcare and medical research to identify and address gaps and bottlenecks. The workshop took place in Milan (Italy) on January 19-20, 2018, involving 45 participants who were mainly representatives of the patient community, but also included experts from clinical centers, industry and regulatory bodies. In order to provide practical examples and constructive suggestions, specific topics were identified upfront. The first set of issues concerned the quality of life at specific phases of a patient's life, such as at the time of diagnosis or during pediatric to adult transition, and patient involvement in medical research on activities in daily living including patient reported outcome measures. The second set of issues concerned the involvement of patients in the management of clinical research tools, such as registries and biobanks, and their participation in study design or marketing authorization processes. Introductory presentations were followed by parallel working group sessions, to gain constructive contributions from all participants. The concept of shared decision making was used to ensure, in discussions, a partnership-based identification of the wishes and needs of all stakeholders involved, and the "ladder of participation" tool served as a model to evaluate the actual and the desired level of patients' involvement in all topics addressed. A general consensus on the outcome of the meeting was collected during the final plenary session. This paper reports the outcome of the workshop and the specific suggestions derived from the analysis of the first set of topics, related to quality of life. The outcomes of the second set of topics are reported elsewhere and are only briefly summarized herein for the sake of completeness. CONCLUSIONS: The neuromuscular community proved to be very active and engaged at different levels in the healthcare initiatives of interest. The workshop participants critically discussed several topics, providing practical examples where different stakeholders could play a role in making a change and bridging gaps. Overall, they indicated the need for education of all stakeholders for better communication, where everyone should become an ambassador to promote real change. Support should also come from institutions and healthcare bodies both at structural and economic level. ispartof: ORPHANET JOURNAL OF RARE DISEASES vol:14 issue:1 ispartof: location:England status: published
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- 2019
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44. Development and validation of a bioanalytical method for the quantification of the CDK4/6 inhibitors abemaciclib, palbociclib, and ribociclib in human and mouse matrices using liquid chromatography-tandem mass spectrometry
- Author
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Martínez-Chávez, Alejandra, Rosing, Hilde, Hillebrand, Michel, Tibben, Matthijs, Schinkel, Alfred H, Beijnen, Jos H, Afd Pharmacoepi & Clinical Pharmacology, and Pharmacoepidemiology and Clinical Pharmacology
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Pyridines ,Metabolite ,Aminopyridines ,02 engineering and technology ,Tissue homogenates ,Tandem mass spectrometry ,01 natural sciences ,Biochemistry ,Piperazines ,Analytical Chemistry ,chemistry.chemical_compound ,Mice ,Plasma ,Liquid chromatography–mass spectrometry ,Tandem Mass Spectrometry ,Ribociclib ,Piperazines/analysis ,Pyridines/analysis ,Chromatography ,Chemistry ,Cyclin-Dependent Kinase 6/antagonists & inhibitors ,021001 nanoscience & nanotechnology ,Dilution ,Cyclin-Dependent Kinase 4/antagonists & inhibitors ,Liquid/methods ,Aminopyridines/analysis ,0210 nano-technology ,Research Paper ,Bioanalysis ,Analyte ,Palbociclib ,Tandem Mass Spectrometry/methods ,Purines/analysis ,Protein precipitation ,Animals ,Humans ,LC-MS/MS ,Protein Kinase Inhibitors/analysis ,Protein Kinase Inhibitors ,010401 analytical chemistry ,Chromatography, Liquid/methods ,Cyclin-Dependent Kinase 4 ,Cyclin-Dependent Kinase 6 ,0104 chemical sciences ,Abemaciclib ,Benzimidazoles/analysis ,Purines ,Benzimidazoles ,Chromatography, Liquid - Abstract
A novel method was developed and validated for the quantification of the three approved CDK4/6 inhibitors (abemaciclib, palbociclib, and ribociclib) in both human and mouse plasma and mouse tissue homogenates (liver, kidney, spleen, brain, and small intestine) using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). For all matrices, pretreatment was performed using 50 μL of sample by protein precipitation with acetonitrile, followed by dilution of the supernatant. Chromatographic separation of the analytes was done on a C18 column using gradient elution. A full validation was performed for human plasma, while a partial validation was executed for mouse plasma and mouse tissue homogenates. The method was linear in the calibration range from 2 to 200 ng/mL, with a correlation coefficient (r) ≥0.996 for each analyte. For both human and mouse plasma, the accuracy and precision were within ±15% and ≤15%, respectively, for all concentrations, except for the lower limit of quantification, where they were within ±20% and ≤20%, respectively. A fit-for-purpose strategy was followed for tissue homogenates, and the accuracy and precision were within ±20% and ≤20%, respectively, for all concentrations. Stability of all analytes in all matrices at different processing and storage conditions was tested; ribociclib and palbociclib were unstable in most tissue homogenates and conditions were modified to increase the stability. The method was successfully applied for the analysis of mouse samples from preclinical studies. A new ribociclib metabolite was detected in mouse plasma samples with the same m/z transition as the parent drug. Electronic supplementary material The online version of this article (10.1007/s00216-019-01932-w) contains supplementary material, which is available to authorized users.
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- 2019
45. Phase I/II study with ruthenium compound NAMI-A and gemcitabine in patients with non-small cell lung cancer after first line therapy
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Leijen, Suzanne, Burgers, Sjaak A, Baas, Paul, Pluim, Dick, Tibben, Matthijs, van Werkhoven, Erik, Alessio, Enzo, Sava, Gianni, Beijnen, Jos H, Schellens, Jan H M, Sub Clinical Pharmacology, Pharmacoepidemiology and Clinical Pharmacology, Sub Clinical Pharmacology, Pharmacoepidemiology and Clinical Pharmacology, Pulmonology, Other departments, Leijen, Suzanne, Burgers, Sjaak A, Baas, Paul, Pluim, Dick, Tibben, Matthij, van Werkhoven, Erik, Alessio, Enzo, Sava, Gianni, Beijnen, Jos H, and Schellens, Jan H. M.
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Male ,Lung Neoplasms ,Pharmacology ,Gastroenterology ,Deoxycytidine ,chemistry.chemical_compound ,Non-small cell lung cancer ,Carcinoma, Non-Small-Cell Lung ,Antineoplastic Combined Chemotherapy Protocols ,NAMI-A ,Pharmacology (medical) ,Clinical investigation ,Middle Aged ,Phase II ,Anticancer ,Treatment Outcome ,Oncology ,Toxicity ,Ruthenium Compounds ,Female ,medicine.symptom ,medicine.drug ,Adult ,medicine.medical_specialty ,Ruthenium ,Antimetastatic ,Maximum Tolerated Dose ,Nausea ,Neutropenia ,Clinical study ,Phase I ,Pharmacokinetics ,Internal medicine ,medicine ,Organometallic Compounds ,Humans ,Dimethyl Sulfoxide ,Lung cancer ,Adverse effect ,Aged ,business.industry ,medicine.disease ,Gemcitabine ,chemistry ,business - Abstract
Background This phase I/II study determined the maximal tolerable dose, dose limiting toxicities, antitumor activity, the pharmacokinetics and pharmacodynamics of ruthenium compound NAMI-A in combination with gemcitabine in Non-Small Cell Lung Cancer patients after first line treatment. Methods Initial dose escalation of NAMI-A was performed in a 28 day cycle: NAMI-A as a 3 h infusion through a port-a-cath at a starting dose of 300 mg/m(2) at day 1, 8 and 15, in combination with gemcitabine 1,000 mg/m(2) at days 2, 9 and 16. Subsequently, dose escalation of NAMI-A in a 21 day schedule was explored. At the maximal tolerable dose level of this schedule an expansion group was enrolled of which 15 patients were evaluable for response. Results Due to frequent neutropenic dose interruptions in the third week, the 28 day schedule was amended into a 21 day schedule. The maximal tolerable dose was 300 and 450 mg/m(2) of NAMI-A (21 day schedule). Main adverse events consisted of neutropenia, anemia, elevated liver enzymes, transient creatinine elevation, nausea, vomiting, constipation, diarrhea, fatigue, and renal toxicity. Conclusion NAMI-A administered in combination with gemcitabine is only moderately tolerated and less active in NSCLC patients after first line treatment than gemcitabine alone.
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- 2015
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46. Predictive Genetic Testing: The <scp>H</scp> untington Disease Model
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Emilia K. Bijlsma and Aad Tibben
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medicine.medical_specialty ,medicine.diagnostic_test ,Informed consent ,Genetic counseling ,medicine ,Disease ,Genetic Status ,Age of onset ,Psychology ,Psychiatry ,Predictive testing ,Genetic testing ,Test (assessment) - Abstract
Predictive or presymptomatic genetic testing enables individuals at risk for a hereditary late-onset disease to learn about their genetic status before symptoms have appeared. The predictive testing protocol for Huntington disease (HD) safeguards the interests of test candidates and has served as a model for other diseases. Most people seen for genetic counselling regarding HD are the asymptomatic children of an affected parent. Predictive testing provides the opportunity to get relief from the anguish of being at risk, to have prenatal tests or preimplantation genetic testing, to have children free from the disorder and to make informed plans for the future regarding marriage, education, professional career and finances. The common experience has been that tested individuals found relief from their prior psychological distress and that they benefited psychologically from testing. Having children proved to be an additional stress factor for partners. Key concepts: Predictive testing provides the opportunity to get relief from uncertainty and prepare better for the future. Preimplantation genetic testing enables couples to have a pregnancy without the burden of termination after an unfavourable prenatal test result. At 55 years of age and being not symptomatic, there is still a 25% empirical chance of being a carrier of the Huntington's gene. The Huntington disease CAG repeat length accounts for roughly 50–77% of the variation in the age of onset. Predictive testing requires informed consent by the individual at risk and the provision of psychological support. Predictive testing for adult-onset disorders without treatment options should not be offered to children and adolescents. Exclusion testing is an important option for an individual at 25% risk because the genetic status of his at-risk parent does not need to be revealed. Counselling test candidates at 25% risk to get Huntington disease requires a family system approach. The predictive test candidate's beliefs about causation and emotional, social and cultural issues may affect the perception of the information that is given in genetic counselling. Keywords: predictive; presymptomatic; prenatal; Huntington disease
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- 2016
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47. Abstract 6322: The role of multidrug efflux transporters and CYP3A in the pharmacokinetics and tissue distribution of abemaciclib and its active metabolites
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Hilde Rosing, Maria C. Lebre, Alejandra Martinez Chavez, Alfred H. Schinkel, Jos H. Beijnen, and Matthijs M. Tibben
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0301 basic medicine ,Cancer Research ,Aromatase inhibitor ,Abcg2 ,biology ,CYP3A4 ,CYP3A ,medicine.drug_class ,business.industry ,Pharmacology ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Oncology ,Pharmacokinetics ,Oral administration ,030220 oncology & carcinogenesis ,Humanized mouse ,medicine ,biology.protein ,business ,Active metabolite - Abstract
Abemaciclib is the third CDK4/6 inhibitor approved by the U.S. Food and Drug Administration to treat some types of breast cancer in combination with an aromatase inhibitor. Currently it is also in clinical development to treat other types of cancer, including lung and brain cancers. Abemaciclib is mainly metabolized by CYP3A4, with the formation of three active metabolites with similar potency to abemaciclib, including N-desethylabemaciclib (M2), hydroxyabemaciclib (M20) and N-desethylhydroxyabemaciclib. The systemic exposure and/or tissue distribution of these active compounds could be affected by drug transporters and CYP3A enzymes, and hence the efficacy and safety of abemaciclib. In this study we aimed to determine the effect of P-glycoprotein (ABCB1), breast cancer resistance protein (ABCG2), and CYP3A on the pharmacokinetics and tissue distribution of abemaciclib and its active metabolites. We performed pharmacokinetic experiments in several mouse models, including ABC transporter knockout (Abcb1a/1b-/-;Abcg2-/-), Cyp3a knockout (Cyp3a-/-), a humanized mouse model with the expression of human CYP3A4 in liver and small intestine in a Cyp3a-/- background (Cyp3aXAV), and wild-type mice. To support these studies, we set up a bioanalytical method using LC-MS/MS for the (semi-)quantification of abemaciclib and its metabolites. After a single oral administration of abemaciclib at 10 mg/kg, the plasma exposure (AUC0-24h) of abemaciclib was not significantly different, but the AUC0-24h of N-desethylabemaciclib increased 5.3-fold in Abcb1a/1b-/-;Abcg2-/- compared to the wild-type mice. In Abcb1a/1b-/-;Abcg2-/- mice also the brain-to-plasma ratio of abemaciclib and N-desethylabemaciclib increased respectively 25- and 4-fold relative to wild-type mice. Regarding CYP3A, the abemaciclib plasma exposure increased 3.1-fold in Cyp3a-/- compared to the wild-type mice, and it decreased 7.6-fold in Cyp3aXAV compared to the Cyp3a-/- mice. However, the plasma exposure of N-desethylabemaciclib was not significantly different among these mouse strains. No other meaningful differences were observed including the distribution of abemaciclib and N-desethylabemaciclib in other tissues. Based on our preliminary data, Abcb1a/1b and/or Abcg2 limit the penetration of abemaciclib and N-desethylabemaciclib into the brain, and they also decrease the oral exposure of the active metabolite N-desethylabemaciclib. CYP3A4 extensively metabolizes abemaciclib, restricting the plasma exposure of the parental drug, but without significantly altering the plasma exposure of N-desethylabemaciclib. It therefore might be important to consider the high risk of variation in oral exposure of abemaciclib due to variable CYP3A4 activity. The insights gained from this study may be useful to optimize the clinical use of abemaciclib, especially for the treatment of brain tumors. Citation Format: Alejandra Martinez Chavez, Matthijs M. Tibben, Maria C. Lebre, Hilde Rosing, Jos H. Beijnen, Alfred H. Schinkel. The role of multidrug efflux transporters and CYP3A in the pharmacokinetics and tissue distribution of abemaciclib and its active metabolites [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6322.
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- 2020
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48. Risk Assessment for Huntington's Disease for (Future) Offspring Requires Offering Preconceptional CAG Analysis to Both Partners
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Guido de Wert, Wybo Dondorp, Christine E. M. de Die-Smulders, Aad Tibben, Moniek Losekoot, Emilia K. Bijlsma, Metamedica, RS: CAPHRI - R6 - Promoting Health & Personalised Care, RS: GROW - R4 - Reproductive and Perinatal Medicine, MUMC+: DA KG Polikliniek (9), and Klinische Genetica
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0301 basic medicine ,Male ,GUIDELINES ,prenatal genetic testing ,FAMILIES ,0302 clinical medicine ,Trinucleotide Repeats ,Pregnancy ,Medicine ,Predictive testing ,preimplantation genetic diagnosis ,CAG repeat ,education.field_of_study ,medicine.diagnostic_test ,AGE-OF-ONSET ,Obstetrics ,ORIGIN ,intermediate alleles ,REPEAT INSTABILITY ,Huntington's disease ,Pedigree ,REDUCED PENETRANCE ALLELES ,Huntington Disease ,embryonic structures ,Female ,Adult ,medicine.medical_specialty ,preconceptional ,Offspring ,Genetic counseling ,Population ,Context (language use) ,Genetic Counseling ,Preimplantation genetic diagnosis ,DIAGNOSIS ,Risk Assessment ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Humans ,Genetic Testing ,education ,Alleles ,Genetic testing ,HIGH-FREQUENCY ,business.industry ,partner testing ,medicine.disease ,GENE ,030104 developmental biology ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
Amongst the main reasons people at risk for Huntington's disease (HD) have for undergoing predictive genetic testing are planning a family and prevention of passing on an expanded CAG-repeat to future offspring. After having received an unfavourable test result, a couple may consider prenatal testing in the foetus or preimplantation genetic diagnostic testing (PGD) in embryos. Testing of the foetus or embryos is possible by means of direct testing of the expanded repeat. Optimal reliability in testing the foetus or embryos requires the establishment of the origin of the repeats of both parents in the foetus. For PGD the analysis is combined with or sometimes solely based on identification of the at-risk haplotype in the embryo. This policy implies that in the context of direct testing, the healthy partner's CAG repeat lengths in the HD gene are also tested, but with the expectation that the repeat lengths of the partner are within the normal range, with the proviso that the partner's pedigree is free of clinically confirmed HD. However, recent studies have shown that the expanded repeat has been observed more often in the general population than previously estimated. Moreover, we have unexpectedly observed an expanded repeat in the non-HD partner in four cases which had far-reaching consequences. Hence, we propose that in the context of reproductive genetic counselling, prior to a planned pregnancy, and irrespective of the outcome of the predictive test in the HD-partner, the non-HD partner should also be given the option of being tested on the expanded allele. International recommendations for predictive testing for HD should be adjusted.
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- 2019
49. Reply to Oliver W Quarrell et al.: 'Letter in response to Tibben et al., Risk Assessment for Huntington's Disease for (Future) Offspring Requires Offering Preconceptional CAG Analysis to Both Partners'
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Wybo Dondorp, Moniek Losekoot, Guido de Wert, Christine E. M. de Die-Smulders, Emilia K. Bijlsma, Aad Tibben, RS: GROW - R4 - Reproductive and Perinatal Medicine, RS: CAPHRI - R6 - Promoting Health & Personalised Care, Metamedica, MUMC+: DA KG Polikliniek (9), and Klinische Genetica
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medicine.medical_specialty ,medicine.diagnostic_test ,Offspring ,business.industry ,MEDLINE ,Guidelines as Topic ,medicine.disease ,Risk Assessment ,Cellular and Molecular Neuroscience ,Huntington Disease ,Trinucleotide Repeats ,Huntington's disease ,medicine ,Humans ,Genetic Testing ,Neurology (clinical) ,Allele ,Psychiatry ,business ,Risk assessment ,Alleles ,Genetic testing - Published
- 2019
50. Uncertainties in Genome Sequencing
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Barbara B. Biesecker, Aad Tibben, and Joel Vos
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media_common.quotation_subject ,Genomics ,Ambiguity ,law.invention ,Optimism ,Risk analysis (engineering) ,law ,Mutation (genetic algorithm) ,Credibility ,CLARITY ,Psychological resilience ,Psychology ,Return of results ,media_common - Abstract
Uncertainties pervade life and medicine; genomics is no exception. Yet, return of results from genomic sequencing greatly exceeds the frequency of uncertain results of single-gene testing and of uncertain results in medicine generally. Undergoing genomic sequencing comes with a high probability of the return of variants of unknown clinical significance (VUS). A VUS is a genetic variant whose association with disease risk is unknown yet. Existing information about a variant lacks reliability, credibility, or adequacy to classify the sequence change either as a normal variation (benign) or a disease-causing mutation and is therefore ambiguous. As such, informing patients to establish the expectation for VUS results at the time of obtaining consent, exploring with patients how they may respond to uncertain results, and helping them navigate uncertain results upon return, are all valuable but challenging aspects of implementing genomic sequencing. Overall, there is a widespread need to help research participants, patients, and the public learn to expect and accept uncertainties from genomic tests for the foreseeable future. Additionally, individuals may benefit from differentiation of uncertainties that can be modified (aleatory) and those that cannot (epistemic). For example, the uncertainties about whether a person with a mutation that predisposes to hereditary cancer risk will develop cancer are not modifiable—it will happen or not (epistemic). In contrast, the degree of risk may be reduced by prophylactic surgery (aleatory). In one case, patients must come to manage that which is not modifiable and in the other they may effectively pursue opportunities to reduce the uncertainty. While most patients find psychological and behavioral approaches to manage both types of uncertainties, healthcare providers can expedite the process of identifying and pursuing aleatory uncertainties to mitigate negative health outcomes. Significant variation in how patients manage uncertainties relates to differences in the extent to which patients need clarity or are able to tolerate ambiguity. Personality traits such as optimism and resilience are associated with lower perceptions of uncertainties and higher psychological wellbeing.
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- 2019
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