RESUMO
The self-organized dynamics of vortex-like rotating waves, which are also known as scroll waves, are the basis of the formation of complex spatiotemporal patterns in many excitable chemical and biological systems. In the heart, filament-like phase singularities that are associated with three-dimensional scroll waves are considered to be the organizing centres of life-threatening cardiac arrhythmias. The mechanisms that underlie the onset, maintenance and control of electromechanical turbulence in the heart are inherently three-dimensional phenomena. However, it has not previously been possible to visualize the three-dimensional spatiotemporal dynamics of scroll waves inside cardiac tissues. Here we show that three-dimensional mechanical scroll waves and filament-like phase singularities can be observed deep inside the contracting heart wall using high-resolution four-dimensional ultrasound-based strain imaging. We found that mechanical phase singularities co-exist with electrical phase singularities during cardiac fibrillation. We investigated the dynamics of electrical and mechanical phase singularities by simultaneously measuring the membrane potential, intracellular calcium concentration and mechanical contractions of the heart. We show that cardiac fibrillation can be characterized using the three-dimensional spatiotemporal dynamics of mechanical phase singularities, which arise inside the fibrillating contracting ventricular wall. We demonstrate that electrical and mechanical phase singularities show complex interactions and we characterize their dynamics in terms of trajectories, topological charge and lifetime. We anticipate that our findings will provide novel perspectives for non-invasive diagnostic imaging and therapeutic applications.
Assuntos
Arritmias Cardíacas/diagnóstico por imagem , Arritmias Cardíacas/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Contração Miocárdica , Animais , Arritmias Cardíacas/patologia , Cálcio/metabolismo , Simulação por Computador , Feminino , Potenciais da Membrana , Modelos Biológicos , Coelhos , Suínos , Porco Miniatura , UltrassonografiaRESUMO
Malignant cardiac tachyarrhythmias are associated with complex spatiotemporal excitation of the heart. The termination of these life-threatening arrhythmias requires high-energy electrical shocks that have significant side effects, including tissue damage, excruciating pain, and worsening prognosis. This significant medical need has motivated the search for alternative approaches that mitigate the side effects, based on a comprehensive understanding of the nonlinear dynamics of the heart. Cardiac optogenetics enables the manipulation of cellular function using light, enhancing our understanding of nonlinear cardiac function and control. Here, we investigate the efficacy of optically resonant feedback pacing (ORFP) to terminate ventricular tachyarrhythmias using numerical simulations and experiments in transgenic Langendorff-perfused mouse hearts. We show that ORFP outperforms the termination efficacy of the optical single-pulse (OSP) approach. When using ORFP, the total energy required for arrhythmia termination, i.e., the energy summed over all pulses in the sequence, is 1 mJ. With a success rate of 50%, the energy per pulse is 40 times lower than with OSP with a pulse duration of 10 ms. We demonstrate that even at light intensities below the excitation threshold, ORFP enables the termination of arrhythmias by spatiotemporal modulation of excitability inducing spiral wave drift.
Assuntos
Arritmias Cardíacas , Optogenética , Animais , Camundongos , Retroalimentação , Arritmias Cardíacas/terapia , Coração , Luz , Potenciais de AçãoRESUMO
Background: The combination of intermediate-dose cytarabine plus mitoxantrone (IMA) can induce high complete remission rates with acceptable toxicity in elderly patients with acute myeloid leukemia (AML). We present the final results of a randomized-controlled trial comparing IMA with the standard 7 + 3 induction regimen consisting of continuous infusion cytarabine plus daunorubicin (DA). Patients and methods: Patients with newly diagnosed AML >60 years were randomized to receive either intermediate-dose cytarabine (1000 mg/m2 twice daily on days 1, 3, 5, 7) plus mitoxantrone (10 mg/m2 days 1-3) (IMA) or standard induction therapy with cytarabine (100 mg/m2 continuously days 1-7) plus daunorubicin (45 mg/m2 days 3-5) (DA). Patients in complete remission after DA received intermediate-dose cytarabine plus amsacrine as consolidation treatment, whereas patients after IMA were consolidated with standard-dose cytarabine plus mitoxantrone. Results: Between February 2005 and October 2009, 485 patients were randomized; 241 for treatment arm DA and 244 for IMA; 76% of patients were >65 years. The complete response rate after DA was 39% [95% confidence interval (95% CI): 33-45] versus 55% (95% CI: 49-61) after IMA (odds ratio 1.89, P = 0.001). The 6-week early-death rate was 14% in both arms. Relapse-free survival curves were superimposable in the first year, but separated afterwards, resulting in 3-year relapse-free survival rates of 29% versus 14% in the DA versus IMA arms, respectively (P = 0.042). The median overall survival was 10 months in both arms (P = 0.513). Conclusion: The dose escalation of cytarabine in induction therapy lead to improved remission rates in the elderly AML patients. This did not translate into a survival advantage, most likely due to differences in consolidation treatment. Thus, effective consolidation strategies need to be further explored. In combination with an effective consolidation strategy, the use of intermediate-dose cytarabine in induction may improve curative treatment for elderly AML patients.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Mitoxantrona/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citarabina/efeitos adversos , Daunorrubicina/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitoxantrona/efeitos adversos , Indução de Remissão , Análise de SobrevidaRESUMO
BACKGROUND: The value of allogeneic hematopoietic cell transplantation (alloHCT) as postremission treatment is not well defined for patients with intermediate-risk acute myeloid leukemia (AML) without FLT3-ITD, biallelic CEBPA-, or NPM1 mutations (here referred to as NPM1mut-neg/CEBPAdm-neg/FLT3-ITDneg AML) in first complete remission (CR1). PATIENTS AND METHODS: We addressed this question using data from two prospective randomized controlled trials on intensive induction- and risk-stratified postremission therapy. The NPM1mut-neg/CEBPAdm-neg/FLT3-ITDneg AML subgroup comprised 497 patients, aged 18-60 years. RESULTS: In donor versus no-donor analyses, patients with a matched related donor had a longer relapse-free survival (HR 0.5; 95% CI 0.3-0.9, P = 0.02) and a trend toward better overall survival (HR 0.6, 95% CI 0.3-1.1, P = 0.08) compared with patients who received postremission chemotherapy. Notably, only 58% of patients in the donor group were transplanted in CR1. We therefore complemented the donor versus no-donor analysis with multivariable Cox regression analyses, where alloHCT was tested as a time-dependent covariate: overall survival (HR 0.58, 95% CI 0.37-0.9, P = 0.02) and relapse-free survival (HR 0.51, 95% CI 0.34-0.76; P = 0.001) for patients who received alloHCT compared with chemotherapy in CR1 were significantly longer. CONCLUSION: Outside clinical trials, alloHCT should be the preferred postremission treatment of patients with intermediate risk NPM1mut-neg/CEBPAdm-neg/FLT3-ITDneg AML in CR1. CINICALTRIALS.GOV IDENTIFIER: NCT00180115, NCT00180102.
Assuntos
Biomarcadores Tumorais/genética , Proteínas Estimuladoras de Ligação a CCAAT/genética , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/terapia , Mutação , Proteínas Nucleares/genética , Tirosina Quinase 3 Semelhante a fms/genética , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Nucleofosmina , Prognóstico , Estudos Prospectivos , Indução de Remissão , Taxa de Sobrevida , Transplante Homólogo , Adulto JovemRESUMO
Allogeneic stem cell transplantation is potentially curative, but associated with post-transplantation complications, including cytomegalovirus (CMV) infections. An effective immune response requires T cells recognizing CMV epitopes via their T cell receptors (TCRs). Little is known about the TCR repertoire, in particular the TCR-α repertoire and its clinical relevance in patients following stem cell transplantation. Using next-generation sequencing we examined the TCR-α repertoire of CD8(+) T cells and CMV-specific CD8(+) T cells in four patients. Additionally, we performed single-cell TCR-αß sequencing of CMV-specific CD8(+) T cells. The TCR-α composition of human leucocyte antigen (HLA)-A*0201 CMVpp65- and CMVIE -specific T cells was oligoclonal and defined by few dominant clonotypes. Frequencies of single clonotypes reached up to 11% of all CD8(+) T cells and half of the total CD8(+) T cell repertoire was dominated by few CMV-reactive clonotypes. Some TCR-α clonotypes were shared between patients. Gene expression of the circulating CMV-specific CD8(+) T cells was consistent with chronically activated effector memory T cells. The CD8(+) T cell response to CMV reactivation resulted in an expansion of a few TCR-α clonotypes to dominate the CD8(+) repertoires. These results warrant further larger studies to define the ability of oligoclonally expanded T cell clones to achieve an effective anti-viral T cell response in this setting.
Assuntos
Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Epitopos/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Idoso , Sequência de Aminoácidos , Antígenos Virais/genética , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Células Clonais , Citomegalovirus/crescimento & desenvolvimento , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , Epitopos/genética , Feminino , Regulação da Expressão Gênica , Antígeno HLA-A2/genética , Antígeno HLA-A2/imunologia , Humanos , Memória Imunológica , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia Linfocítica Crônica de Células B/terapia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Análise de Sequência de DNA , Transdução de Sinais , Análise de Célula Única , Transplante HomólogoRESUMO
It has been demonstrated that physical exercise benefits younger patients undergoing allogeneic haematopoietic stem cell transplantation (allo-HSCT). We designed a prospective pilot study investigating whether elderly patients (>60 years) would also be able to participate in such a programme. It consisted of physiotherapist-supervised alternating endurance and resistance workouts on 6 of 7 days a week. Sixteen consecutive patients undergoing allo-HSCT were enrolled into the study. The median age was 64.5 years. Twelve patients participated in the programme until the time of discharge (75%) from the transplant unit. Therefore, the predefined criteria regarding feasibility were met. The reason for drop out was transplantation associated mortality in all patients (n = 4). Adherence was very good with a median of 85% attended training sessions. No adverse events were recorded. The endurance capacity dropped by 7% and lower extremity strength improved by 2% over time. Quality of life decreased during the study period, with global health being significantly worse at the time of discharge. In conclusion, a combined and intensified strength and endurance exercise programme is feasible and safe in a population of elderly patients undergoing allo-HSCT. Further research should focus on exploring effect sizes of such an intervention by conducting randomised controlled trials.
Assuntos
Terapia por Exercício/métodos , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Cooperação do Paciente , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Transplante HomólogoRESUMO
BACKGROUND: For patients with primary refractory or relapsed acute myeloid leukemia (AML), no treatment of choice has until now been defined to date. Cytarabine (Ara-C) is a key drug in the treatment of AML patients, there is still uncertainly regarding its optimal dose and infusion schedule. The aim of this study is to examine the impact of the Ara-C infusion schedule used as part of an intensive salvage regimen, in patients with relapsed or refractory AML. PATIENTS AND METHODS: A total of 252 adult patients (median age 59 years) with relapsed or refractory AML were randomly allocated to receive either Mito-FLAG with Ara-C as bolus (B) (1000 mg/m(2) over 1 h, every 12 h, days 1-5), or continuous infusion (CI) (150 mg/m(2) over 24 h, days 1-5) in combination with mitoxantrone, fludarabine, and granulocyte colony-stimulating factor (G-CSF). Autologous or allogeneic hematopoietic stem-cell transplantation was offered as consolidation therapy. Primary end point was the rate of complete remissions (CRs) after the first cycle of Mito-FLAG. RESULTS: The CR rates after Mito-FLAG (B) and Mito-FLAG (CI) were 54% and 43%, respectively (P = 0.1). There was no statistical difference between rates of grade 3/4 neutropenia, thrombocytopenia, mucositis, renal, and liver toxicity. More infections occurred, however, after Mito-FLAG (B) compared with Mito-FLAG (CI) (80% versus 69%, P = 0.01). The early death rate by day 42 was 13% in both arms. Median disease-free survival was comparable in the two arms (7.8 versus 7.1 months, P = 0.53) as was overall survival (7.1 versus 6.6 months, P = 0.53). CONCLUSION: A 5-day course of Ara-C 2 × 1000 mg/m(2) administered as bolus versus Ara-C 150 mg/m(2) administered by CI (in combination with mitoxantrone, fludarabine, and G-CSF), resulted in a nonsignificant trend in response rates in favor of Mito-FLAG (B) at the selected dose levels, but no differences in the survival outcome in relapsed or refractory AML. CLINICAL TRIAL NUMBER: LN_NN_2004_39/EudraCT number 2014-000083-18.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Terapia de Salvação , Adolescente , Adulto , Idoso , Citarabina/administração & dosagem , Vias de Administração de Medicamentos , Feminino , Seguimentos , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Humanos , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados , Adulto JovemRESUMO
BACKGROUND: Autologous stem-cell transplantation (autoSCT) is considered a standard treatment of non-frail patients with mantle cell lymphoma (MCL), but little is known about outcome of MCL patients relapsing after autoSCT. We therefore sought to analyse the outcome after autoSCT failure and the efficacy of a rescue stem-cell transplantation (SCT) in this setting. PATIENTS AND METHODS: Patients with MCL were eligible if they had relapsed after autoSCT performed between 2000 and 2009. A total of 1054 patients could be identified in the EBMT registry. By contacting the transplant centres, a full dataset could be retrieved for 360 patients. RESULTS: Median overall survival (OS) after relapse of the whole study group was 19 months. A long (>12 months) interval between autoSCT and relapse [P < 0.001, hazard ratio (HR) 0.62], primary refractory disease (P < 0.02, HR 1.92), prior high-dose ARA-C treatment (P = 0.04, HR 1.43), and the year of relapse (P = 0.02, HR 0.92) significantly influenced OS from relapse in multivariate analysis. Eighty patients (22%) received a rescue allogeneic SCT (alloSCT). Relapse incidence, non-relapse mortality, and OS 2 years after alloSCT was 33% [confidence interval (95% CI 21% to 45%)], 30% (95% CI 19% to 42%), and 46% (95% CI 33% to 59%), respectively. Remission duration after autoSCT was the only variable significantly affecting the outcome of salvage alloSCT. In contrast, rescue autoSCT was not associated with long-term disease control. However, individual patients survived long term even without salvage transplantation. CONCLUSIONS: MCL recurrence within 1 year after autoSCT has an extremely dismal outcome, while the prognosis of patients with longer remission durations after autoSCT is significantly better. AlloSCT may offer the possibility of durable survival when performed for patients with a remission duration of more than 12 months after first autoSCT, but the favourable effect of a salvage alloSCT in this setting needs further validation.
Assuntos
Linfoma de Célula do Manto/mortalidade , Transplante de Células-Tronco , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfoma de Célula do Manto/patologia , Linfoma de Célula do Manto/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Terapia de Salvação , Transplante Autólogo , Falha de Tratamento , Resultado do TratamentoRESUMO
To analyze the outcome of solid organ transplantation (SOT) in patients who had undergone allogeneic hematopoietic stem cell transplantation (HSCT), a questionnaire survey was carried out within 107 European Group of Blood and Marrow Transplantation centers. This study covered HSCT between 1984 and 2007 in Europe. Forty-five SOT in 40 patients were reported. Fifteen liver, 15 renal, 13 lung, 1 heart and 1 skin transplantations were performed in 28 centers. Overall survival (OS) of patients after SOT was 78% at 5 years (95% confidence interval [CI], 64% to 92%). OS at 5 years was 100% for renal, 71% (95% CI, 46% to 96%) for liver and 63% (95% CI, 23% to 100%) for lung transplant recipients. The 2-year-incidence of SOT failure was 20% (95% CI, 4% to 36%) in patients with graft-versus-host disease (GvHD) and 7% (95% CI, 0% to 21%) in patients without GvHD before SOT. The relapse incidence for underlying malignant diseases was 4% at 5 years (95% CI, 0% to 12%). In summary, this study shows that selected patients receiving SOT after HSCT have a remarkably good overall and organ survival. These data indicate that SOT should be considered in selected patients with single organ failure after HSCT.
Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Órgãos/efeitos adversos , Adolescente , Adulto , Criança , Pré-Escolar , Europa (Continente)/epidemiologia , Feminino , Sobrevivência de Enxerto , Doença Enxerto-Hospedeiro/epidemiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Transplante de Órgãos/mortalidade , Recidiva , Estudos Retrospectivos , Análise de SobrevidaRESUMO
Preliminary data suggest that allogeneic stem cell transplantation (allo-SCT) may be effective in T-prolymphocytic leukemia (T-PLL). The purpose of the present observational study was to assess the outcome of allo-SCT in patients aged 65 years or younger with a centrally confirmed diagnosis of T-PLL. Patients were consecutively registered with the EBMT at the time of transplantation and followed by routine EBMT monitoring but with an extended dataset. Between 2007 and 2012, 37 evaluable patients (median age 56 years) were accrued. Pre-treatment contained alemtuzumab in 95% of patients. Sixty-two percent were in complete remission (CR) at the time of allo-SCT. Conditioning contained total body irradiation with 6 Gy or more (TBI6) in 30% of patients. With a median follow-up of 50 months, the 4-year non-relapse mortality, relapse incidence, progression-free (PFS) and overall survival were 32, 38, 30 and 42%, respectively. By univariate analysis, TBI6 in the conditioning was the only significant predictor for a low relapse risk, and an interval between diagnosis and allo-SCT of more than 12 months was associated with a lower NRM. This study confirms for the first time prospectively that allo-SCT can provide long-term disease control in a sizable albeit limited proportion of patients with T-PLL.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Prolinfocítica de Células T , Sistema de Registros , Condicionamento Pré-Transplante , Irradiação Corporal Total , Adolescente , Adulto , Idoso , Aloenxertos , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Prolinfocítica de Células T/mortalidade , Leucemia Prolinfocítica de Células T/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de SobrevidaRESUMO
As low trough levels of mycophenolic acid (MPA) have been measured in recipients of allo-SCTs, we performed a pilot study targeting mycophenolate mofetil (MMF) doses according to the MPA area under the concentration (AUC) levels. Twenty-nine patients were transplanted from matched sibling (n=7) and unrelated donors (n=22). Tacrolimus was given orally from day -1 to achieve trough blood levels of 5-10 ng/ml. MMF was started on day 0 at 1500 mg intravenously b.i.d. AUC measurements of MPA by HPLC were scheduled on days 3, 7 and 11 after transplantation. The MMF dose was modified to achieve an MPA AUC of 35-60 microg/ml/h. With the respective adjustments 66 and 75% surpassed the lower AUC target on days 7 and 11, respectively. The cumulative incidence of grade III-IV acute GVHD was 28% (8/29). Eight out of 24 evaluable patients (33%) suffer from limited (n=3) or extensive (n=5) chronic GVHD. Overall, the results of this study suggest that targeting of MPA exposure is feasible early after transplantation. A simplified MMF targeting strategy based on MPA C(max) or C(2h) levels seems to be warranted in future trials involving more patients at later time points in the outpatient setting.
Assuntos
Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/uso terapêutico , Ácido Micofenólico/análogos & derivados , Adulto , Idoso , Área Sob a Curva , Monitoramento de Medicamentos , Feminino , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/farmacocinética , Ácido Micofenólico/uso terapêutico , Transplante HomólogoRESUMO
The aim of this project was to identify situations where allogeneic stem cell transplantation (allo-SCT) might be considered as a preferred treatment option for patients with B-cell chronic lymphocytic leukemia (CLL). Based on a MEDLINE search and additional sources, a consented proposal was drafted, refined and approved upon final discussion by an international expert panel. Key elements of the consensus are (1) allo-SCT is a procedure with evidence-based efficacy in poor-risk CLL; (2) although definition of 'poor-risk CLL' requires further investigation, allo-SCT is a reasonable treatment option for younger patients with (i) non-response or early relapse (within 12 months) after purine analogues, (ii) relapse within 24 months after having achieved a response with purine-analogue-based combination therapy or autologous transplantation, and (iii) patients with p53 abnormalities requiring treatment; and (3) optimum transplant strategies may vary according to distinct clinical situations and should be defined in prospective trials. This is the first attempt to define standard indications for allo-SCT in CLL. Nevertheless, whenever possible, allo-SCT should be performed within disease-specific prospective clinical protocols in order to continuously refine transplant indications according to new developments in risk assessment and treatment of CLL.
Assuntos
Leucemia Linfocítica Crônica de Células B/terapia , Transplante de Células-Tronco , Adolescente , Adulto , Fatores Etários , Medicina Baseada em Evidências , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia Linfocítica Crônica de Células B/fisiopatologia , Pessoa de Meia-Idade , Prognóstico , Recidiva , Fatores de Risco , Fatores de TempoRESUMO
Monitoring of minimal residual disease (MRD) has become an important clinical aspect for early relapse detection during follow-up care after cancer treatment. Still, the sensitive detection of single base pair point mutations via Next-Generation Sequencing (NGS) is hampered mainly due to high substitution error rates. We evaluated the use of NGS for the detection of low-level variants on an Ion Torrent PGM system. As a model case we used the c.1849Gâ¯>â¯T (p.Val617Phe) mutation of the JAK2-gene. Several reaction parameters (e.g. choice of DNA-polymerase) were evaluated and a comprehensive analysis of substitution errors was performed. Using optimized conditions, we reliably detected JAK2 c.1849Gâ¯>â¯T VAFs in the range of 0.01-0.0015% which, in combination with results obtained from clinical data, validated the feasibility of NGS-based MRD detection. Particularly, PCR-induced transitions (mainly Gâ¯>â¯A and Câ¯>â¯T) were the major source of error, which could be significantly reduced by the application of proofreading enzymes. The integration of NGS results for several common point mutations in various oncogenes (i.e. IDH1 and 2, c-KIT, DNMT3A, NRAS, KRAS, BRAF) revealed that the prevalent transition vs. transversion bias (3.57:1) has an impact on site-specific detection limits of low-level mutations. These results may help to select suitable markers for MRD detection and to identify individual cut-offs for detection and quantification.
RESUMO
Optical mapping is a widely used imaging technique for investigating cardiac electrophysiology in intact, Langendorff-perfused hearts. Mechanical contraction of cardiac tissue, however, may result in severe motion artifacts and significant distortion of the fluorescence signals. Therefore, pharmacological uncoupling is widely used to reduce tissue motion. Recently, various image processing algorithms have been proposed to reduce motion artifacts. We will review these technological developments. Furthermore, we will present a novel approach for the three-dimensional, marker-free reconstruction of contracting Langendorff-perfused intact hearts under physiological conditions. The algorithm allows disentangling the fluorescence signals (e.g. membrane voltage or intracellular calcium) from the mechanical motion (e.g. tissue strain). We will discuss the algorithms reconstruction accuracy, resolution, and robustness using experimental data from Langendorff-perfused rabbit hearts.
Assuntos
Coração/diagnóstico por imagem , Coração/fisiologia , Fenômenos Mecânicos , Imagens com Corantes Sensíveis à Voltagem/métodos , Animais , Artefatos , Imageamento Tridimensional , Movimento , CoelhosRESUMO
Donor T-cells transferred after allogeneic stem cell transplantation (alloSCT) can result in long-term disease control in myeloma by the graft-versus-myeloma (GvM) effect. However, T-cell therapy may show differential effectiveness against bone marrow (BM) infiltration and focal myeloma lesions resulting in different control and progression patterns. Outcomes of 43 myeloma patients who underwent T-cell-depleted alloSCT with scheduled donor lymphocyte infusion (DLI) were analyzed with respect to diffuse BM infiltration and focal progression. For comparison, 12 patients for whom a donor search was started but no alloSCT was performed, were analyzed. After DLI, complete disappearance of myeloma cells in BM occurred in 86% of evaluable patients. The probabilities of BM progression-free survival (PFS) at 2 years after start of donor search, alloSCT and DLI, were 17% (95% confidence interval 0-38%), 51% (36-66%), and 62% (44-80%) respectively. In contrast, the probabilities of focal PFS at 2 years after start of donor search, alloSCT and DLI, were 17% (0-38%), 30% (17-44%) and 28% (11-44%), respectively. Donor-derived T-cell responses effectively reduce BM infiltration, but not focal progression in myeloma, illustrating potent immunological responses in BM with only limited effect of T-cells on focal lesions.
Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Mieloma Múltiplo/terapia , Linfócitos T/transplante , Adulto , Medula Óssea/patologia , Progressão da Doença , Feminino , Humanos , Depleção Linfocítica , Transfusão de Linfócitos , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Doadores de TecidosRESUMO
For young patients with high-risk CLL, BTK-/PI3K-inhibitors or allogeneic stem cell transplantation (alloHCT) are considered. Patients with a low risk of non-relapse mortality (NRM) but a high risk of failure of targeted therapy may benefit most from alloHCT. We performed Cox regression analyses to identify risk factors for 2-year NRM and 5-year event-free survival (using EFS as a surrogate for long-term disease control) in a large, updated EBMT registry cohort (n= 694). For the whole cohort, 2-year NRM was 28% and 5-year EFS 37%. Higher age, lower performance status, unrelated donor type and unfavorable sex-mismatch had a significant adverse impact on 2-year NRM. Two-year NRM was calculated for good- and poor-risk reference patients. Predicted 2-year-NRM was 11 and 12% for male and female good-risk patients compared with 42 and 33% for male and female poor-risk patients. For 5-year EFS, age, performance status, prior autologous HCT, remission status and sex-mismatch had a significant impact, whereas del(17p) did not. The model-based prediction of 5-year EFS was 55% and 64%, respectively, for male and female good-risk patients. Good-risk transplant candidates with high-risk CLL and limited prognosis either on or after failure of targeted therapy should still be considered for alloHCT.
Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia Linfocítica Crônica de Células B/terapia , Adulto , Fatores Etários , Idoso , Doadores de Sangue , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco , Fatores de Risco , Fatores Sexuais , Análise de Sobrevida , Transplante Homólogo , Falha de Tratamento , Adulto JovemRESUMO
Even with the availability of targeted drugs, allogeneic hematopoietic cell transplantation (allo-HCT) is the only therapy with curative potential for patients with CLL. Cure can be assessed by comparing long-term survival of patients to the matched general population. Using data from 2589 patients who received allo-HCT between 2000 and 2010, we used landmark analyses and methods from relative survival analysis to calculate excess mortality compared with an age-, sex- and calendar year-matched general population. Estimated event-free survival, overall survival and non-relapse mortality (NRM) 10 years after allo-HCT were 28% (95% confidence interval (CI), 25-31), 35% (95% CI, 32-38) and 40% (95% CI, 37-42), respectively. Patients who passed the 5-year landmark event-free survival (N=394) had a 79% probability (95% CI, 73-85) of surviving the subsequent 5 years without an event. Relapse and NRM contributed equally to treatment failure. Five-year mortality for 45- and 65-year-old reference patients who were event-free at the 5-year landmark was 8% and 47% compared with 3% and 14% in the matched general population, respectively. The prospect of long-term disease-free survival remains an argument to consider allo-HCT for young patients with high-risk CLL, and programs to understand and prevent late causes of failure for long-term survivors are warranted, especially for older patients.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/terapia , Adolescente , Adulto , Fatores Etários , Idoso , Aloenxertos , Criança , Intervalo Livre de Doença , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Sociedades Médicas , Taxa de Sobrevida , Fatores de TempoRESUMO
Ibrutinib, a recently approved inhibitor of Bruton's tyrosine kinase (BTK), has shown great efficacy in patients with high-risk CLL. Nevertheless, there are few data regarding its use in patients who relapsed after allogeneic stem cell transplantation (alloSCT). We report clinical data from five CLL patients treated with ibrutinib for relapse after first or even second allogeneic transplantation. Additionally, we performed analyses on cytokine levels and direct measuring of CD4 Th1 and CD4 Th2 cells to evaluate possible clinically relevant immunomodulatory effects of ibrutinib. All patients achieved partial responses including one minimal residual disease (MRD)-negative remission. Within 1 year of follow-up, no relapse was observed. One patient died of severe pneumonia while on ibrutinib treatment. Beside this, no unexpected adverse events were observed. Flow cytometry and analyses of T cell-mediated cytokine levels (IL10 and TNFα) did not reveal substantial changes in T-cell distribution in favor of a CD4 Th1 T-cell shift in our patients. No acute exacerbation of GvHD was reported. In conclusion, these results support further evaluation of ibrutinib in CLL patients relapsing after alloSCT.
Assuntos
Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem , Terapia de Salvação/métodos , Adenina/análogos & derivados , Adulto , Idoso , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/terapia , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Piperidinas , Pirazóis/efeitos adversos , Pirimidinas/efeitos adversos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
In patients with relapsed or refractory (r/r) acute myeloid leukemia (AML), long-term disease control can only be achieved by allogeneic hematopoietic stem cell transplantation (HSCT). We studied the safety and efficacy of clofarabine-based salvage therapy. The study was designed as phase II, multicenter, intent-to-transplant (ITT) study. A total of 84 patients with r/r AML were enrolled. All patients received at least one cycle of CLARA (clofarabine 30 mg/m(2) and cytarabine 1 g/m(2), days 1-5). Chemo-responsive patients with a donor received HSCT in aplasia after first CLARA. Generally, HSCT was performed as soon as possible. The conditioning regimen consisted of clofarabine (4 × 30 mg/m(2)) and melphalan (140 mg/m(2)). The median patient age was 61 years (range 40-75). On day 15 after start of CLARA, 26% of patients were in a morphologically leukemia-free state and 79% exposed a reduction in bone marrow blasts. Overall, 67% of the patients received HSCT within the trial. The primary end point, defined as complete remission after HSCT, was achieved by 60% of the patients. According to the ITT, overall survival at 2 years was 43% (95% confidence interval (CI), 32-54%). The 2-year disease-free survival for transplanted patients was 52% (95% CI, 40-69%). Clofarabine-based salvage therapy combined with allogeneic HSCT in aplasia shows promising results in patients with r/r AML.