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1.
Br J Haematol ; 191(5): 806-815, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33065767

RESUMEN

High-dose chemotherapy (HDC) and autologous stem cell transplantation (ASCT) are used as consolidation in first remission (CR1) in some centres for untreated, transformed indolent B-cell lymphoma (Tr-iNHL) but the evidence base is weak. A total of 319 patients with untreated Tr-iNHL meeting prespecified transplant eligibility criteria [age <75, LVEF ≥45%, no severe lung disease, CR by positron emission tomography or computed tomography ≥3 months after at least standard cyclophosphamide, doxorubicin, vincristine and prednisolone with rituximab (R-CHOP) intensity front-line chemotherapy] were retrospectively identified. Non-diffuse large B-cell lymphoma transformations were excluded. About 283 (89%) patients had follicular lymphoma, 30 (9%) marginal-zone lymphoma and six (2%) other subtypes. Forty-nine patients underwent HDC/ASCT in CR1, and a 1:2 propensity-score-matched cohort of 98 patients based on age, stage and high-grade B-cell lymphoma with MYC, BCL2 and/or BCL6 rearrangements (HGBL-DH) was generated. After a median follow-up of 3·7 (range 0·1-18·3) years, ASCT was associated with significantly superior progression-free survival [hazard ratio (HR) 0·51, 0·27-0·98; P = 0·043] with a trend towards inferior overall survival (OS; HR 2·36;0·87-6·42; P = 0·1) due to more deaths from progressive disease (8% vs. 4%). Forty (41%) patients experienced relapse in the non-ASCT cohort - 15 underwent HDC/ASCT with seven (47%) ongoing complete remission (CR); 10 chimeric antigen receptor-modified T-cell (CAR-T) therapy with 6 (60%) ongoing CR; 3 allogeneic SCT with 2 (67%) ongoing CR. Although ASCT in CR1 improves initial duration of disease control in untreated Tr-iNHL, the impact on OS is less clear with effective salvage therapies in this era of CAR-T.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Reordenamiento Génico , Trasplante de Células Madre Hematopoyéticas , Linfoma de Células B de la Zona Marginal , Linfoma Folicular , Proteínas de Neoplasias/genética , Tomografía de Emisión de Positrones , Adulto , Anciano , Autoinjertos , Ciclofosfamida/administración & dosificación , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Linfoma de Células B de la Zona Marginal/diagnóstico por imagen , Linfoma de Células B de la Zona Marginal/genética , Linfoma de Células B de la Zona Marginal/mortalidad , Linfoma de Células B de la Zona Marginal/terapia , Linfoma Folicular/diagnóstico por imagen , Linfoma Folicular/genética , Linfoma Folicular/mortalidad , Linfoma Folicular/terapia , Masculino , Persona de Mediana Edad , Prednisona/administración & dosificación , Rituximab/administración & dosificación , Tasa de Supervivencia , Vincristina/administración & dosificación
4.
Br J Cancer ; 111(6): 1072-9, 2014 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-25072255

RESUMEN

BACKGROUND: Central nervous system (CNS) relapse in diffuse large B-cell lymphoma (DLBCL) is a devastating complication; the optimal prophylactic strategy remains unclear. METHODS: We performed a multicentre, retrospective analysis of patients with DLBCL with high risk for CNS relapse as defined by two or more of: multiple extranodal sites, elevated serum LDH and B symptoms or involvement of specific high-risk anatomical sites. We compared three different strategies of CNS-directed therapy: intrathecal (IT) methotrexate (MTX) with (R)-CHOP 'group 1'; R-CHOP with IT MTX and two cycles of high-dose intravenous (IV) MTX 'group 2'; dose-intensive systemic antimetabolite-containing chemotherapy (Hyper-CVAD or CODOXM/IVAC) with IT/IV MTX 'group 3'. RESULTS: Overall, 217 patients were identified (49, 125 and 43 in groups 1-3, respectively). With median follow-up of 3.4 (range 0.2-18.6) years, 23 CNS relapses occurred (12, 10 and 1 in groups 1-3 respectively). The 3-year actuarial rates (95% CI) of CNS relapse were 18.4% (9.5-33.1%), 6.9% (3.5-13.4%) and 2.3% (0.4-15.4%) in groups 1-3, respectively (P=0.009). CONCLUSIONS: The addition of high-dose IV MTX and/or cytarabine was associated with lower incidence of CNS relapse compared with IT chemotherapy alone. However, these data are limited by their retrospective nature and warrant confirmation in prospective randomised studies.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Sistema Nervioso Central/prevención & control , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Metotrexato/administración & dosificación , Lesión Renal Aguda/inducido químicamente , Administración Intravenosa , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias del Sistema Nervioso Central/secundario , Ciclofosfamida/administración & dosificación , Citarabina/administración & dosificación , Dexametasona/administración & dosificación , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Etopósido/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Ifosfamida/administración & dosificación , Inyecciones Espinales , Linfoma de Células B Grandes Difuso/patología , Masculino , Metotrexato/efectos adversos , Persona de Mediana Edad , Prednisona/administración & dosificación , Recurrencia , Estudios Retrospectivos , Medición de Riesgo , Rituximab , Tasa de Supervivencia , Vincristina/administración & dosificación , Adulto Joven
5.
Intern Med J ; 44(12b): 1277-82, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25482740

RESUMEN

This article reports the findings of a survey developed to assess the current use of antifungal prophylaxis among haematology and infectious disease clinicians across Australia and New Zealand, and their alignment with existing consensus guidelines for the use of antifungal agents in the haematology/oncology setting (published 2008). Surveyed clinicians largely followed the current recommendations for prophylaxis in the setting of induction chemotherapy for acute myeloid leukaemia, as well as autologous and low-risk allogeneic haemopoietic stem cell transplantation (HSCT). In keeping with guideline recommendations, posaconazole was the agent used by most centres for high-risk allogeneic HSCT. However, its routine continuation for 75-100 days post-transplantation without de-escalation suggested use beyond those indications described in the 2008 guidelines, namely pre-engraftment neutropenia and graft-versus-host disease. Variations in practice were observed in other settings, such as acute lymphoblastic leukaemia and myelodysplastic syndrome, reflecting the general lack of evidence for antifungal prophylaxis in these patient populations and changing perceptions of risk. With regard to the availability of testing in cases of suspected breakthrough IFD, 40% of centres did not have access to investigative bronchoscopy within 48 h of referral, and results of Aspergillus galactomannan (GM), fungal polymerase chain reaction and therapeutic drug monitoring (TDM) were not available within 48 h in 83%, 90% and 85% of centres respectively. The survey's findings will influence the recommendations provided in the updated 2014 consensus guidelines for the use of antifungal agents in the haematology/oncology setting.


Asunto(s)
Aspergilosis/microbiología , Enfermedad Injerto contra Huésped/microbiología , Neoplasias Hematológicas/inmunología , Neoplasias Hematológicas/cirugía , Trasplante de Células Madre Hematopoyéticas/métodos , Infecciones Oportunistas/microbiología , Profilaxis Pre-Exposición , Antifúngicos/uso terapéutico , Aspergilosis/prevención & control , Australia , Quimioprevención , Conferencias de Consenso como Asunto , Recolección de Datos , Pruebas Diagnósticas de Rutina , Enfermedad Injerto contra Huésped/prevención & control , Neoplasias Hematológicas/complicaciones , Humanos , Nueva Zelanda , Infecciones Oportunistas/prevención & control , Guías de Práctica Clínica como Asunto , Triazoles/uso terapéutico
6.
Intern Med J ; 44(12b): 1283-97, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25482741

RESUMEN

There is a strong argument for the use of antifungal prophylaxis in high-risk patients given the significant mortality associated with invasive fungal disease, the late identification of these infections, and the availability of safe and well-tolerated prophylactic medications. Clinical decisions about which patients should receive prophylaxis and choice of antifungal agent should be guided by risk stratification, knowledge of local fungal epidemiology, the efficacy and tolerability profile of available agents, and estimates such as number needed to treat and number needed to harm. There have been substantial changes in practice since the 2008 guidelines were published. These include the availability of new medications and/or formulations, and a focus on refining and simplifying patient risk stratification. Used in context, these guidelines aim to assist clinicians in providing optimal preventive care to this vulnerable patient demographic.


Asunto(s)
Antifúngicos/uso terapéutico , Neoplasias Hematológicas/inmunología , Trasplante de Células Madre Hematopoyéticas , Infecciones Oportunistas/microbiología , Infecciones Oportunistas/prevención & control , Profilaxis Pre-Exposición , Aspergilosis/prevención & control , Candidiasis/prevención & control , Consenso , Análisis Costo-Beneficio , Adhesión a Directriz , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Pruebas de Sensibilidad Microbiana , Selección de Paciente , Guías de Práctica Clínica como Asunto , Profilaxis Pre-Exposición/economía , Medición de Riesgo
7.
Semin Hematol ; 60(2): 118-124, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37099031

RESUMEN

Recent advances in the understanding of Waldenström macroglobulinemia (WM) biology have impacted the development of effective novel agents and improved our knowledge of how the genomic background of WM may influence selection of therapy. Consensus Panel 7 (CP7) of the 11th International Workshop on WM was convened to examine the current generation of completed and ongoing clinical trials involving novel agents, consider updated data on WM genomics, and make recommendations on the design and prioritization of future clinical trials. CP7 considers limited duration and novel-novel agent combinations to be the priority for the next generation of clinical trials. Evaluation of MYD88, CXCR4 and TP53 at baseline in the context of clinical trials is crucial. The common chemoimmunotherapy backbones, bendamustine-rituximab (BR) and dexamethasone, rituximab and cyclophosphamide (DRC), may be considered standard-of-care for the frontline comparative studies. Key unanswered questions include the definition of frailty in WM; the importance of attaining a very good partial response or better (≥VGPR), within stipulated time frame, in determining survival outcomes; and the optimal treatment of WM populations with special needs.


Asunto(s)
Macroglobulinemia de Waldenström , Humanos , Macroglobulinemia de Waldenström/tratamiento farmacológico , Macroglobulinemia de Waldenström/genética , Rituximab/uso terapéutico , Consenso , Ciclofosfamida/uso terapéutico , Clorhidrato de Bendamustina/uso terapéutico
8.
Semin Hematol ; 60(2): 80-89, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37147252

RESUMEN

The consensus panel 2 (CP2) of the 11th International Workshop on Waldenström's macroglobulinemia (IWWM-11) has reviewed and incorporated current data to update the recommendations for treatment approaches in patients with relapsed or refractory WM (RRWM). The key recommendations from IWWM-11 CP2 include: (1) Chemoimmunotherapy (CIT) and/or a covalent Bruton tyrosine kinase (cBTKi) strategies are important options; their use should reflect the prior upfront strategy and are subject to their availability. (2) In selecting treatment, biological age, co-morbidities and fitness are important; nature of relapse, disease phenotype and WM-related complications, patient preferences and hematopoietic reserve are also critical factors while the composition of the BM disease and mutational status (MYD88, CXCR4, TP53) should also be noted. (3) The trigger for initiating treatment in RRWM should utilize knowledge of patients' prior disease characteristics to avoid unnecessary delays. (4) Risk factors for cBTKi related toxicities (cardiovascular dysfunction, bleeding risk and concurrent medication) should be addressed when choosing cBTKi. Mutational status (MYD88, CXCR4) may influence the cBTKi efficacy, and the role of TP53 disruptions requires further study) in the event of cBTKi failure dose intensity could be up titrated subject to toxicities. Options after BTKi failure include CIT with a non-cross-reactive regimen to one previously used CIT, addition of anti-CD20 antibody to BTKi, switching to a newer cBTKi or non-covalent BTKi, proteasome inhibitors, BCL-2 inhibitors, and new anti-CD20 combinations are additional options. Clinical trial participation should be encouraged for all patients with RRWM.


Asunto(s)
Antineoplásicos , Macroglobulinemia de Waldenström , Humanos , Macroglobulinemia de Waldenström/tratamiento farmacológico , Macroglobulinemia de Waldenström/genética , Factor 88 de Diferenciación Mieloide/genética , Consenso , Recurrencia Local de Neoplasia/inducido químicamente , Recurrencia Local de Neoplasia/tratamiento farmacológico , Antineoplásicos/uso terapéutico
9.
Ann Oncol ; 28(5): 920-921, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28379289
11.
Intern Med J ; 41(1b): 90-101, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21272173

RESUMEN

Administration of empiric antimicrobial therapy is standard practice in the management of neutropenic fever, but there remains considerable debate about the selection of an optimal regimen. In view of emerging evidence regarding efficacy and toxicity differences between empiric treatment regimens, and strong evidence of heterogeneity in clinical practice, the current guidelines were developed to provide Australian clinicians with comprehensive guidance for selecting an appropriate empiric strategy in the setting of neutropenic fever. Beta-lactam monotherapy is presented as the treatment of choice for all clinically stable patients while early treatment with combination antibiotic therapy is considered for patients at higher risk. Due consideration is given to the appropriate use of glycopeptides in this setting. Several clinical caveats, accounting for institution- and patient-specific risk factors, are provided to help guide the judicious use of the agents described. Detailed recommendations are also provided regarding time to first dose, timing of blood cultures, selection of a first-line antibiotic regimen, subsequent modification of antibiotic choice and cessation of therapy.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Fiebre/tratamiento farmacológico , Neoplasias/complicaciones , Neutropenia/complicaciones , Adulto , Antibacterianos/administración & dosificación , Antibacterianos/clasificación , Profilaxis Antibiótica/normas , Australia , Bacteriemia/sangre , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Infecciones Bacterianas/sangre , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/diagnóstico , Técnicas Bacteriológicas , Instituciones Oncológicas/normas , Manejo de la Enfermedad , Farmacorresistencia Bacteriana Múltiple , Fiebre/etiología , Humanos , Huésped Inmunocomprometido , Medición de Riesgo , Índice de Severidad de la Enfermedad , beta-Lactamas/administración & dosificación , beta-Lactamas/uso terapéutico
12.
Diabetologia ; 53(8): 1700-8, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20461357

RESUMEN

AIMS/HYPOTHESIS: The purpose of the study was to test prospectively whether healthy individuals with a family history of type 2 diabetes are more susceptible to adverse metabolic effects during experimental overfeeding. METHODS: We studied the effects of 3 and 28 days of overfeeding by 5,200 kJ/day in 41 sedentary individuals with and without a family history of type 2 diabetes (FH+ and FH- respectively). Measures included body weight, fat distribution (computed tomography) and insulin sensitivity (hyperinsulinaemic-euglycaemic clamp). RESULTS: Body weight was increased compared with baseline at 3 and 28 days in both groups (p < 0.001), FH+ individuals having gained significantly more weight than FH- individuals at 28 days (3.4 +/- 1.6 vs 2.2 +/- 1.4 kg, p < 0.05). Fasting serum insulin and C-peptide were increased at 3 and 28 days compared with baseline in both groups, with greater increases in FH+ than in FH- for insulin at +3 and +28 days (p < 0.01) and C-peptide at +28 days (p < 0.05). Fasting glucose also increased at both time points, but without a significant group effect (p = 0.1). Peripheral insulin sensitivity decreased in the whole cohort at +28 days (54.8 +/- 17.7 to 50.3 +/- 15.6 micromol min(-1) [kg fat-free mass](-1), p = 0.03), and insulin sensitivity by HOMA-IR decreased at both time points (p < 0.001) and to a greater extent in FH+ than in FH- (p = 0.008). Liver fat, subcutaneous and visceral fat increased similarly in the two groups (p < 0.001). CONCLUSIONS: Overfeeding induced weight and fat gain, insulin resistance and hepatic fat deposition in healthy individuals. However, individuals with a family history of type 2 diabetes gained more weight and greater insulin resistance by HOMA-IR. The results of this study suggest that healthy individuals with a family history of type 2 diabetes are predisposed to adverse effects of overfeeding. TRIAL REGISTRATION: ClinicalTrials.gov NCT00562393 FUNDING: The study was funded by the National Health and Medical Research Council (NHMRC), Australia (no. #427639).


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Conducta Alimentaria/fisiología , Hipernutrición/fisiopatología , Aumento de Peso/fisiología , Adulto , Análisis de Varianza , Australia , Composición Corporal , Péptido C/sangre , Diabetes Mellitus Tipo 2/sangre , Femenino , Predisposición Genética a la Enfermedad , Glucosa/metabolismo , Humanos , Insulina/sangre , Resistencia a la Insulina , Leptina/sangre , Masculino , Persona de Mediana Edad , Hipernutrición/sangre , Factores de Riesgo , Conducta Sedentaria
14.
Leukemia ; 32(1): 83-91, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28592889

RESUMEN

In the phase 3 RESONATE study, ibrutinib demonstrated superior progression-free survival (PFS), overall survival (OS) and overall response rate (ORR) compared with ofatumumab in relapsed/refractory CLL patients with high-risk prognostic factors. We report updated results from RESONATE in these traditionally chemotherapy resistant high-risk genomic subgroups at a median follow-up of 19 months. Mutations were detected by Foundation One Heme Panel. Baseline mutations in the ibrutinib arm included TP53 (51%), SF3B1 (31%), NOTCH1 (28%), ATM (19%) and BIRC3 (14%). Median PFS was not reached, with 74% of patients randomized to ibrutinib alive and progression-free at 24 months. The improved efficacy of ibrutinib vs ofatumumab continues in all prognostic subgroups including del17p and del11q. No significant difference within the ibrutinib arm was observed for PFS across most genomic subtypes, although a subset carrying both TP53 mutation and del17p had reduced PFS compared with patients with neither abnormality. Reduced PFS or OS was not evident in patients with only del17p. PFS was significantly better for ibrutinib-treated patients in second-line vs later lines of therapy. The robust clinical activity of ibrutinib continues to show ongoing efficacy and acceptable safety consistent with prior reports, independent of various known high-risk mutations.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/patología , Mutación/genética , Adenina/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Antineoplásicos/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , Mutación/efectos de los fármacos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Piperidinas , Pronóstico , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Proteína p53 Supresora de Tumor/genética
15.
Blood Rev ; 31(5): 318-327, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28499646

RESUMEN

The anti-CD20 antibodies represent a major advancement in the therapeutic options available for chronic lymphocytic leukemia. The addition of rituximab, ofatumumab and obinutuzumab to various chemotherapy regimens has led to considerable improvements in both response and survival. Ocaratuzumab, veltuzumab and ublituximab are currently being explored within the trial setting. We review the current status of these antibodies, and discuss how their mechanisms of action may impact on the choice of combinations with novel small molecule agents.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Terapia Molecular Dirigida , Antígenos CD20/metabolismo , Antineoplásicos Inmunológicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Ensayos Clínicos como Asunto , Descubrimiento de Drogas , Humanos , Leucemia Linfocítica Crónica de Células B/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Rituximab/administración & dosificación , Resultado del Tratamiento
16.
Obes Rev ; 18(7): 776-790, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28474421

RESUMEN

Skeletal muscle extracellular matrix remodelling has been proposed as a new feature associated with obesity and metabolic dysfunction. Exercise training improves muscle function in obesity, which may be mediated by regulatory effects on the muscle extracellular matrix. This review examined available literature on skeletal muscle extracellular matrix remodelling during obesity and the effects of exercise. A non-systematic literature review was performed on PubMed of publications from 1970 to 2015. A total of 37 studies from humans and animals were retained. Studies reported overall increases in gene and protein expression of different types of collagen, growth factors and enzymatic regulators of the skeletal muscle extracellular matrix in obesity. Only two studies investigated the effects of exercise on skeletal muscle extracellular matrix during obesity, with both suggesting a regulatory effect of exercise. The effects of exercise on muscle extracellular matrix seem to be influenced by the duration and type of exercise training with variable effects from a single session compared with a longer duration of exercise. More studies are needed to elucidate the mechanisms behind skeletal muscle extracellular matrix remodelling during obesity and the effects of exercise.


Asunto(s)
Ejercicio Físico/fisiología , Matriz Extracelular/fisiología , Músculo Esquelético/fisiopatología , Obesidad/fisiopatología , Animales , Humanos
17.
Nutr Diabetes ; 5: e187, 2015 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-26657013

RESUMEN

Skeletal muscle extracellular matrix (ECM) remodelling has been proposed as a feature of the pathogenic milieu associated with obesity and metabolic dysfunction. Whether muscle ECM is associated with impaired physical function in obese conditions is unknown. C57BL/6 mice were fed a high-fat diet (HFD) or chow for 5, 10 and 25 weeks. Non-invasive physiological tests (hang wire, hang mesh and grip strength) to assess neuromuscular function and motor co-ordination were performed. Genes related to ECM structure (COL1, COL3, COL6A2, SPARC), growth factors (TGFB1, TGFB2, CTGF, VEGF) and muscle function (DMD (Dp147), CPN3, DAG1) were measured in gastrocnemius muscle using real-time PCR and COL1, 3 and 6 protein were measured by western immunoblot. Compared with chow, HFD mice had two to six-fold lower muscle strength (hang wire test; raw data and multiplied by body weight) at all time-points (P<0.001) and two-fold lower hang mesh and grip strength at 10 weeks (P<0.05). At 5 weeks, COL1, COL3 and COL6 gene expression, but not protein levels were three to eight-fold lower in HFD compared with chow. In the HFD group at 5 weeks, greater COL3 and 6 gene expression were associated with poorer hang wire performance. For the first time, our results demonstrate links between muscle ECM structure and physical function in obesity.

18.
Leukemia ; 29(4): 783-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25138588

RESUMEN

The BTK (Bruton's tyrosine kinase) inhibitor ibrutinib is associated with an increased risk of bleeding. A previous study reported defects in collagen- and adenosine diphosphate (ADP)-dependent platelet responses when ibrutinib was added ex vivo to patient samples. Whereas the collagen defect is expected given the central role of BTK in glycoprotein VI signaling, the ADP defect lacks a mechanistic explanation. In order to determine the real-life consequences of BTK platelet blockade, we performed light transmission aggregometry in 23 patients receiving ibrutinib treatment. All patients had reductions in collagen-mediated platelet aggregation, with a significant association between the degree of inhibition and the occurrence of clinical bleeding or bruising (P=0.044). This collagen defect was reversible on drug cessation. In contrast to the previous ex vivo report, we found no in vivo ADP defects in subjects receiving standard doses of ibrutinib. These results establish platelet light transmission aggregometry as a method for gauging, at least qualitatively, the severity of platelet impairment in patients receiving ibrutinib treatment.


Asunto(s)
Antineoplásicos/efectos adversos , Plaquetas/efectos de los fármacos , Colágeno/farmacología , Hemorragia/diagnóstico , Agregación Plaquetaria/efectos de los fármacos , Pirazoles/efectos adversos , Pirimidinas/efectos adversos , Adenina/análogos & derivados , Adenosina Difosfato/farmacología , Anciano , Anciano de 80 o más Años , Antineoplásicos/administración & dosificación , Plaquetas/patología , Células Cultivadas , Femenino , Hemorragia/inducido químicamente , Hemorragia/patología , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/patología , Linfoma de Células del Manto/tratamiento farmacológico , Linfoma de Células del Manto/patología , Masculino , Persona de Mediana Edad , Piperidinas , Pirazoles/administración & dosificación , Pirimidinas/administración & dosificación , Índice de Severidad de la Enfermedad
19.
J Bone Miner Res ; 15(6): 1158-68, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10841185

RESUMEN

The objectives of this study were to investigate the different effects on muscle mass and cancellous (proximal tibial metaphysis [PTM]) and cortical (tibial shaft [TX]) bone mass of sham-operated and orchidectomized (ORX) male rats by making rats rise to erect bipedal stance for feeding. Specially designed raised cages (RC) were used so that the rats had to rise to erect bipedal stance to eat and drink for 12 weeks. Dual-energy X-ray absorptiometry (DEXA) and peripheral quantitative computerized tomography (pQCT) were used to estimate the lean leg mass and bone mineral. Static and dynamic histomorphometry were performed on the triple-labeled undecalcified sections. We found that making the intact rats rise to erect bipedal stance for feeding increased muscle mass, cortical bone volume, and periosteal bone formation. Orchidectomy increased net losses of bone next to the marrow by increasing bone turnover. Making the ORX rats rise to erect bipedal stance increased muscle mass, partially prevented cancellous bone loss in the PTM, and prevented net cortical bone loss in TX induced by ORX by depressing cancellous and endocortical high bone turnover and stimulating periosteal bone formation. The bone-anabolic effects were achieved mainly in the first 4 weeks in the PTM and by 8 weeks in the TX. These findings suggested that making the rats rise to erect bipedal stance for feeding helped to increase muscle mass and cortical bone mass in the tibias of intact rats, increase muscle mass, and partially prevented cancellous and net cortical bone loss in ORX rats.


Asunto(s)
Osteoporosis/prevención & control , Condicionamiento Físico Animal , Animales , Huesos/fisiología , Conducta Alimentaria , Masculino , Músculos/fisiología , Orquiectomía , Osteoporosis/etiología , Esfuerzo Físico , Postura , Ratas , Ratas Sprague-Dawley
20.
J Bone Miner Res ; 8(1): 83-91, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8427051

RESUMEN

A young girl had tibial osteotomies at age 14 for genu valgum and then had recurrent tibial cysts over a number of years. Hypocalcemia and hyperphosphatemia were first noted at age 21. The diagnosis of pseudohypoparathyroidism was made at age 28, when elevated plasma PTH was detected. Clinical and biochemical features, including a PTH response test and assay of RBC Gs, established the diagnosis of pseudohypoparathyroidism type 1b. Failure to suppress plasma PTH with vitamin D therapy led to an exacerbation of her cystic bone disease; there were widespread lytic lesions radiologically, most of which took up [99mTc]diphosphonate on bone scan. Microradioscopy revealed evidence of resorption of phalangeal tufts. Bone biopsy showed osteitis fibrosa cystica. During an orthopedic procedure, trabecular bone fragments were taken from her right humerus, and bone-derived cells cultured using an explant technique. The cultured cells were osteoblast-like in morphology, fully responsive to PTH, cholera toxin, forskolin, and PGE1 in vitro, and had an alkaline phosphatase and osteocalcin response to 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. Following this examination of skeletal responsiveness, attempts were made to suppress the elevated plasma PTH levels and symptomatic bone disease by optimizing therapy with oral 1,25-(OH)2D3. When bone pain associated with the cystic bone disease failed to resolve, the patient underwent total parathyroidectomy, following which the bone pain gradually resolved. This is the first direct demonstration of PTH responsiveness in cultured bone cells in the syndrome of pseudohypoparathyroidism with osteitis fibrosa cystica.


Asunto(s)
Huesos/efectos de los fármacos , Osteítis Fibrosa Quística/metabolismo , Osteoblastos/efectos de los fármacos , Hormona Paratiroidea/farmacología , Seudohipoparatiroidismo/metabolismo , Adenilil Ciclasas/metabolismo , Adulto , Huesos/citología , Huesos/metabolismo , Células Cultivadas , Femenino , Humanos , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Hormona Paratiroidea/metabolismo , Síndrome
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