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1.
Br J Haematol ; 191(5): 806-815, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33065767

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Rearranjo Gênico , Transplante de Células-Tronco Hematopoéticas , Linfoma de Zona Marginal Tipo Células B , Linfoma Folicular , Proteínas de Neoplasias/genética , Tomografia por Emissão de Pósitrons , Adulto , Idoso , Autoenxertos , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Linfoma de Zona Marginal Tipo Células B/diagnóstico por imagem , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/mortalidade , Linfoma de Zona Marginal Tipo Células B/terapia , Linfoma Folicular/diagnóstico por imagem , Linfoma Folicular/genética , Linfoma Folicular/mortalidade , Linfoma Folicular/terapia , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Rituximab/administração & dosagem , Taxa de Sobrevida , Vincristina/administração & dosagem
2.
Br J Cancer ; 111(6): 1072-9, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25072255

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Nervoso Central/prevenção & controle , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Metotrexato/administração & dosagem , Injúria Renal Aguda/induzido quimicamente , Administração Intravenosa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias do Sistema Nervoso Central/secundário , Ciclofosfamida/administração & dosagem , Citarabina/administração & dosagem , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Seguimentos , Humanos , Ifosfamida/administração & dosagem , Injeções Espinhais , Linfoma Difuso de Grandes Células B/patologia , Masculino , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Recidiva , Estudos Retrospectivos , Medição de Risco , Rituximab , Taxa de Sobrevida , Vincristina/administração & dosagem , Adulto Jovem
3.
Intern Med J ; 44(12b): 1277-82, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25482740

RESUMO

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.


Assuntos
Aspergilose/microbiologia , Doença Enxerto-Hospedeiro/microbiologia , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/cirurgia , Transplante de Células-Tronco Hematopoéticas/métodos , Infecções Oportunistas/microbiologia , Profilaxia Pré-Exposição , Antifúngicos/uso terapêutico , Aspergilose/prevenção & controle , Austrália , Quimioprevenção , Conferências de Consenso como Assunto , Coleta de Dados , Testes Diagnósticos de Rotina , Doença Enxerto-Hospedeiro/prevenção & controle , Neoplasias Hematológicas/complicações , Humanos , Nova Zelândia , Infecções Oportunistas/prevenção & controle , Guias de Prática Clínica como Assunto , Triazóis/uso terapêutico
4.
Intern Med J ; 44(12b): 1283-97, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25482741

RESUMO

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.


Assuntos
Antifúngicos/uso terapêutico , Neoplasias Hematológicas/imunologia , Transplante de Células-Tronco Hematopoéticas , Infecções Oportunistas/microbiologia , Infecções Oportunistas/prevenção & controle , Profilaxia Pré-Exposição , Aspergilose/prevenção & controle , Candidíase/prevenção & controle , Consenso , Análise Custo-Benefício , Fidelidade a Diretrizes , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Testes de Sensibilidade Microbiana , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Profilaxia Pré-Exposição/economia , Medição de Risco
5.
Semin Hematol ; 60(2): 118-124, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37099031

RESUMO

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.


Assuntos
Macroglobulinemia de Waldenstrom , Humanos , Macroglobulinemia de Waldenstrom/tratamento farmacológico , Macroglobulinemia de Waldenstrom/genética , Rituximab/uso terapêutico , Consenso , Ciclofosfamida/uso terapêutico , Cloridrato de Bendamustina/uso terapêutico
6.
Semin Hematol ; 60(2): 80-89, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37147252

RESUMO

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.


Assuntos
Antineoplásicos , Macroglobulinemia de Waldenstrom , Humanos , Macroglobulinemia de Waldenstrom/tratamento farmacológico , Macroglobulinemia de Waldenstrom/genética , Fator 88 de Diferenciação Mieloide/genética , Consenso , Recidiva Local de Neoplasia/induzido quimicamente , Recidiva Local de Neoplasia/tratamento farmacológico , Antineoplásicos/uso terapêutico
7.
Ann Oncol ; 28(5): 920-921, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28379289
9.
Intern Med J ; 41(1b): 90-101, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21272173

RESUMO

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.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Febre/tratamento farmacológico , Neoplasias/complicações , Neutropenia/complicações , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/classificação , Antibioticoprofilaxia/normas , Austrália , Bacteriemia/sangue , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Infecções Bacterianas/sangue , Infecções Bacterianas/complicações , Infecções Bacterianas/diagnóstico , Técnicas Bacteriológicas , Institutos de Câncer/normas , Gerenciamento Clínico , Farmacorresistência Bacteriana Múltipla , Febre/etiologia , Humanos , Hospedeiro Imunocomprometido , Medição de Risco , Índice de Gravidade de Doença , beta-Lactamas/administração & dosagem , beta-Lactamas/uso terapêutico
10.
Diabetologia ; 53(8): 1700-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20461357

RESUMO

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).


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Comportamento Alimentar/fisiologia , Hipernutrição/fisiopatologia , Aumento de Peso/fisiologia , Adulto , Análise de Variância , Austrália , Composição Corporal , Peptídeo C/sangue , Diabetes Mellitus Tipo 2/sangue , Feminino , Predisposição Genética para Doença , Glucose/metabolismo , Humanos , Insulina/sangue , Resistência à Insulina , Leptina/sangue , Masculino , Pessoa de Meia-Idade , Hipernutrição/sangue , Fatores de Risco , Comportamento Sedentário
11.
Leukemia ; 32(1): 83-91, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28592889

RESUMO

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.


Assuntos
Leucemia Linfocítica Crônica de Células B/patologia , Mutação/genética , Adenina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Piperidinas , Prognóstico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Proteína Supressora de Tumor p53/genética
12.
Blood Rev ; 31(5): 318-327, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28499646

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Terapia de Alvo Molecular , Antígenos CD20/metabolismo , Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ensaios Clínicos como Assunto , Descoberta de Drogas , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Rituximab/administração & dosagem , Resultado do Tratamento
13.
Obes Rev ; 18(7): 776-790, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28474421

RESUMO

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.


Assuntos
Exercício Físico/fisiologia , Matriz Extracelular/fisiologia , Músculo Esquelético/fisiopatologia , Obesidade/fisiopatologia , Animais , Humanos
14.
Nutr Diabetes ; 5: e187, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26657013

RESUMO

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.

15.
Leukemia ; 29(4): 783-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25138588

RESUMO

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.


Assuntos
Antineoplásicos/efeitos adversos , Plaquetas/efeitos dos fármacos , Colágeno/farmacologia , Hemorragia/diagnóstico , Agregação Plaquetária/efeitos dos fármacos , Pirazóis/efeitos adversos , Pirimidinas/efeitos adversos , Adenina/análogos & derivados , Difosfato de Adenosina/farmacologia , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Plaquetas/patologia , Células Cultivadas , Feminino , Hemorragia/induzido quimicamente , Hemorragia/patologia , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Piperidinas , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem , Índice de Gravidade de Doença
16.
J Bone Miner Res ; 8(1): 83-91, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8427051

RESUMO

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.


Assuntos
Osso e Ossos/efeitos dos fármacos , Osteíte Fibrosa Cística/metabolismo , Osteoblastos/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , Pseudo-Hipoparatireoidismo/metabolismo , Adenilil Ciclases/metabolismo , Adulto , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Células Cultivadas , Feminino , Humanos , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Hormônio Paratireóideo/metabolismo , Síndrome
17.
J Bone Miner Res ; 15(6): 1158-68, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10841185

RESUMO

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.


Assuntos
Osteoporose/prevenção & controle , Condicionamento Físico Animal , Animais , Osso e Ossos/fisiologia , Comportamento Alimentar , Masculino , Músculos/fisiologia , Orquiectomia , Osteoporose/etiologia , Esforço Físico , Postura , Ratos , Ratos Sprague-Dawley
18.
Endocrinology ; 109(5): 1448-53, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6271531

RESUMO

The regulatory role of vitamin D in bone formation and its interaction with parathyroid hormone (PTH) were analyzed in rats in vivo. The bone apposition rate was determined by measuring the distances between tetracycline lines deposited at 48-h intervals. Vitamin D restriction was associated with a decrease in the bone apposition rate and was paralleled by the expected decrease in serum 25-hydroxyvitamin D3 levels but not by changes in 1,25-dihydroxyvitamin D3 levels. Vitamin D3 repletion restored the apposition rate to normal in parathyroid-intact animals but had no effect in parathyroidectomized animals. Vitamin D repletion of PTH-repleted parathyroidectomized animals restored the bone apposition rate. These results indicate that vitamin D or vitamin D metabolites are required for the expression of the effect of PTH on bone apposition. Conversely, vitamin D repletion only affects the bone formation rate in the presence of PTH, thus suggesting the requirement for PTH-dependent vitamin D metabolism.


Assuntos
Osso e Ossos/fisiopatologia , Colecalciferol/farmacologia , Ergocalciferóis/farmacologia , Deficiência de Vitamina D/fisiopatologia , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Cálcio/sangue , Masculino , Glândulas Paratireoides/fisiologia , Hormônio Paratireóideo/farmacologia , Ratos , Ratos Endogâmicos , Tireoidectomia , Vitamina D/sangue
19.
Endocrinology ; 118(6): 2217-24, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3486118

RESUMO

The linear rate of bone mineral apposition (BMAR) was measured in vitamin D-deficient and vitamin D-sufficient adult rats before and during treatment with either 25-hydroxyvitamin D3 (25OHD3), 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3], or 24,25-dihydroxyvitamin D3 [24,25-(OH)2D3]. Dietary vitamin D restriction caused a fall in BMAR which began after 1 week and fell progressively to a value of 35-50% of control values by 4 weeks. The fall in BMAR was related to a fall in the serum concentrations of 25(OH)D3 and 24,25-(OH)2D3, without a fall in the 1,25-(OH)2D3 concentration. Dietary supplementation of the D-deficient animals with either 25OHD3 or 24,25-(OH)2D3 at doses of 200 ng/day restored BMAR. If vitamin D-deficient animals were thyroparathyroid-ectomized before supplementation with vitamin D metabolites, 24,25-(OH)2D3 administration was without effect on BMAR. The combined administration of PTH and 24,25-(OH)2D3 to such animals led to a restoration of the BMAR to normal. In vitamin D-sufficient animals, parathyroidectomy led to a 50% reduction in BMAR, which could be restored by treatment with PTH alone but not with 24,25-(OH)2D3. Simultaneous treatment of these animals with PTH and 24,25-(OH)2D3 led to a greater than normal increase in BMAR (130% of control) in these animals. These data support the concept that 24,25-(OH)2D3 has a role in the regulation of bone formation and/or mineralization, and demonstrate the interrelation between the effects of PTH and 24,25-(OH)2D3 on bone.


Assuntos
Osso e Ossos/metabolismo , Minerais/metabolismo , Deficiência de Vitamina D/metabolismo , Vitamina D/farmacologia , 24,25-Di-Hidroxivitamina D 3 , Animais , Osso e Ossos/efeitos dos fármacos , Calcifediol/sangue , Calcifediol/farmacologia , Calcitriol/sangue , Calcitriol/farmacologia , Di-Hidroxicolecalciferóis/sangue , Di-Hidroxicolecalciferóis/farmacologia , Masculino , Glândulas Paratireoides/fisiologia , Hormônio Paratireóideo/farmacologia , Ratos , Ratos Endogâmicos
20.
Endocrinology ; 110(2): 506-12, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7056211

RESUMO

The deposition of mineralized bone matrix by differentiated osteoblasts was studied in rats in vivo by labeling the bone with three doses of tetracycline given at 48-h intervals. Only bone formation loci bearing all three tetracycline doses were measured, thus eliminating sites where bone formation was not continuous during the labeling period. Using this technique, the effects of intact bovine parathyroid hormone [bPTH-(1-84)] and of a synthetic amino-terminal fragment of human PTH [hPTH-(1-34)] were measured in thyroparathyroidectomized animals. bPTH-(1-84), administered sc, and hPTH-(1-34), administered iv, caused a dose-dependent increase in the bone apposition. Subcutaneous administration of hPTH-(1-34) in doses varying from 2.7-173.0 pmol/rat.day had no effect, probably due to the degradation of the hormone when administered this way. We also compared the effects of bPTH-(1-84) when administered by either daily sc injections or continuous infusion. Continuous infusion of bPTH-(1-84) resulted in an increased apposition rate. Using a morphometric technique, we also found an increase in both formation and resorption surfaces and a net decrease in the trabecular bone volume in this group. Daily injection of the hormone caused an increase in the bone apposition rate, accompanied by an increase in the formation surface without an increase in the resorption surface. This resulted in a net increase in trabecular bone volume. The results thus suggest that the resorptive effects of bPTH-(1-84) can be separated from the effects of the hormone on the apposition rate.


Assuntos
Desenvolvimento Ósseo/efeitos dos fármacos , Reabsorção Óssea/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , Animais , Masculino , Hormônio Paratireóideo/administração & dosagem , Ratos , Ratos Endogâmicos
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