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1.
Eur J Haematol ; 109(2): 162-165, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35502609

RESUMO

OBJECTIVES: Polatuzumab vedotin with bendamustine and rituximab (Pola-BR) was approved for treatment of transplant-ineligible patients with relapsed/refractory DLBCL (R/R DLBCL). However, the number of patients treated in the GO29365 trial including the extension cohort was limited, and more data evaluating the efficacy of this treatment regimen is needed. METHODS: We analyzed 21 patients with R/R DLBCL to determine real-life efficacy and safety of Pola-BR regimen. Data of all patients entered the database of the NiHiL project (NCT03199066). RESULTS: Median overall survival was 8.7 months, and progression-free survival 3.8 months. The overall response rate was 33%. Grade 3-4 neutropenia was detected in 29%, thrombocytopenia in 38%, anemia in 19%, infections in 24% cases, and peripheral neuropathy in 5%. Discontinuation of treatment was caused by progression in 50%, adverse events in 31%, and intended bridging to CAR-T therapy in 19%. CONCLUSION: Although the outcome of patients is worse than in GO29365 trial, the use of Pola-BR regimen in the real world demonstrates tolerable toxicity profile and efficacy in transplant-ineligible patients with R/R DLBCL. Moreover, this regimen might represent a perspective option as a bridge to CAR-T therapy.


Assuntos
Imunoconjugados , Linfoma Difuso de Grandes Células B , Linfoma não Hodgkin , Receptores de Antígenos Quiméricos , Anticorpos Monoclonais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cloridrato de Bendamustina , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Rituximab
2.
Neoplasma ; 69(6): 1466-1473, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36591807

RESUMO

Burkitt lymphoma (BL) is a rare subtype of non-Hodgkin's lymphoma with an aggressive course. To refine the individual patient's prognosis, the International Prognostic Index for BL (BL-IPI) was recently developed and 4 risk factors (RF) were determined as optimal prognostic cut-off by multivariate analysis: age ≥40 years, lactate dehydrogenase >3× upper limit of normal, ECOG performance status ≥2, and central nervous system involvement. The BL-IPI distinguishes 3 prognostic groups, low (without RF), intermediate (1 RF), and high risk (2-4 RF), with significant differences in survival. The aim of the current project was to perform an external validation of the BL-IPI in 101 patients from the Registry of Czech Lymphoma Study Group diagnosed between 1999 and 2016 (median age, 45 years). The median follow-up was 50.4 months. The induction treatment included rituximab plus chemotherapy in 82% and chemotherapy alone in 18%. The overall response rate was 78% and the complete remission rate was 73%. According to BL-IPI, low/intermediate/high risk was present in 21/35/45% of patients, showing high similarity to the training BL-IPI US (United States) dataset (18/36/46%). There were significant differences in progression-free survival (PFS) and overall survival (OS) between patients with high vs. intermediate risk (PFS: hazard ratio 0.16, 95% confidence interval 0.08-0.31, p<0.0001; OS: hazard ratio 0.17, 95% confidence interval 0.09-0.35, p<0.0001) but not between patients with low vs. intermediate risk. The 3-year OS probability according to BL-IPI with low/intermediate/high risk was 96/76/59% in the BL-IPI training dataset vs. 95/85/45% in our external validation cohort; the 3-year PFS probability with low/intermediate/high risk was 92/72/53% in the BL-IPI training dataset vs. 95/85/42% in our cohort. In summary, our external validation of the BL-IPI confirmed a good separation of high-risk patients, who have a poor prognosis and for whom the new therapeutic approaches are needed; patients with low and intermediate risk had favorable clinical outcomes, and differences between these groups were not significant, likely due to a small number of patients.


Assuntos
Linfoma de Burkitt , Linfoma Difuso de Grandes Células B , Humanos , Pessoa de Meia-Idade , Adulto , Linfoma de Burkitt/tratamento farmacológico , Prognóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Estudos Retrospectivos , República Tcheca/epidemiologia , Sistema de Registros , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
3.
Blood ; 132(22): 2389-2400, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30213873

RESUMO

Follicular lymphoma (FL) is a common indolent B-cell malignancy with a variable clinical course. An unfavorable event in its course is histological transformation to a high-grade lymphoma, typically diffuse large B-cell lymphoma. Recent studies show that genetic aberrations of MYC or its overexpression are associated with FL transformation (tFL). However, the precise molecular mechanisms underlying tFL are unclear. Here we performed the first profiling of expression of microRNAs (miRNAs) in paired samples of FL and tFL and identified 5 miRNAs as being differentially expressed. We focused on one of these miRNAs, namely miR-150, which was uniformly downmodulated in all examined tFLs (∼3.5-fold), and observed that high levels of MYC are responsible for repressing miR-150 in tFL by binding in its upstream region. This MYC-mediated repression of miR-150 in B cells is not dependent on LIN28A/B proteins, which influence the maturation of miR-150 precursor (pri-miR-150) in myeloid cells. We also demonstrated that low miR-150 levels in tFL lead to upregulation of its target, namely FOXP1 protein, which is a known positive regulator of cell survival, as well as B-cell receptor and NF-κB signaling in malignant B cells. We revealed that low levels of miR-150 and high levels of its target, FOXP1, are associated with shorter overall survival in FL and suggest that miR-150 could serve as a good biomarker measurable in formalin-fixed paraffin-embedded tissue. Overall, our study demonstrates the role of the MYC/miR-150/FOXP1 axis in malignant B cells as a determinant of FL aggressiveness and its high-grade transformation.


Assuntos
Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Linfoma Folicular/genética , MicroRNAs/genética , Proteínas Repressoras/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Regulação para Baixo , Humanos , Linfoma Folicular/diagnóstico , Linfoma Folicular/patologia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Prognóstico , Proteínas Proto-Oncogênicas c-myc/genética , Ativação Transcricional , Regulação para Cima
4.
Ann Hematol ; 99(7): 1583-1594, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32506244

RESUMO

Relapsing diffuse large B cell lymphomas (rDLBCL) represent a heterogeneous disease. This heterogeneity should be recognized and reflected, because it can deform the interpretation of clinical trial results. DLBCL patients with the first relapse and without CNS involvement were identified in the Czech Lymphoma Study Group (CLSG) database. Interval-to-therapy (ITT) was defined as the time between the first manifestation of rDLBCL and the start of any treatment. The overall survival (OS) of different ITT cohorts (< 7 vs. 7-21 vs. > 21 days) was compared. In total, 587 rDLBCLs (51.8% males) progressed with a median of 12.8 months (range 1.6 to 152.3) since the initial diagnosis (2000-2017). At the time of relapse, the median age was 67 years (range 22-95). First-line therapy was administered in 99.3% of the patients; CHOP and anti-CD20 were given to 69.2% and 84.7% of the patients, respectively. The salvage immune/chemotherapy was administered in 88.1% of the patients (39.2% platinum-based regimen). The median ITT was 20 days (range 1-851), but 23.2% of patients initiated therapy within 7 days. The 5-year OS was 17.4% (range 10-24.5%) vs. 20.5% (range 13.5-27.4%) vs. 42.2% (range 35.5-48.8%) for ITT < 7 vs. 7-21 vs. > 21 days (p < 0.001). ITT was associated with B symptoms (p 0.004), ECOG (p < 0.001), stage (p 0.002), bulky disease (p 0.005), elevated LDH (p < 0.001), and IPI (p < 0.001). The ITT mirrors the real clinical behavior of rDLBCL. There are patients (ITT < 7 days) with aggressive disease and a poor outcome. Conversely, there are rDLBCLs with ITT ≥ 21 days who survive for a long time.


Assuntos
Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/terapia , Tempo para o Tratamento , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Coortes , Ciclofosfamida/uso terapêutico , República Tcheca/epidemiologia , Bases de Dados Factuais , Progressão da Doença , Doxorrubicina/uso terapêutico , Feminino , Humanos , Linfoma Difuso de Grandes Células B/epidemiologia , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Terapia Neoadjuvante/estatística & dados numéricos , Prednisona/uso terapêutico , Prognóstico , Recidiva , Estudos Retrospectivos , Rituximab/administração & dosagem , Tempo para o Tratamento/estatística & dados numéricos , Resultado do Tratamento , Vincristina/uso terapêutico , Adulto Jovem
5.
J Synchrotron Radiat ; 26(Pt 4): 1310-1315, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31274459

RESUMO

Spatially confined magnetic inhomogeneities were revealed by measuring nuclear forward scattering time spectra on the same sample in two different geometric arrangements. They differ by 180° rotation of the sample around one of the polarization axes. A basic theoretical description of this phenomenon and its relation to a spatial distribution of nuclei featuring different magnetic moments is provided. From an experimental point of view, the violation of rotational invariance was observed for an inhomogeneous Fe81Mo8Cu1B10 metallic glass. The development of magnetic inhomogeneities and their relation to the evolution of time spectra was studied during thermal annealing.

6.
Ann Hematol ; 98(8): 1961-1972, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31065733

RESUMO

Peripheral T cell lymphomas (PTLs) have a globally poor prognosis. The CHOP regimen shows insufficient efficacy; first-line consolidation with autologous stem cell transplantation (auto-SCT) is a promising strategy but has never been confirmed by randomized data. We analyzed retrospectively 906 patients diagnosed with PTL between 1999 and 2015. Chemotherapy was given to 862 patients, and 412 of them were < 60 years. In this subset, we compared induction with CHOP (n = 113) vs. CHOEP (n = 68) and tested auto-SCT (n = 79) vs. no SCT (n = 73) in the intent-to-treat analysis. The median age of the whole cohort at diagnosis was 60 years (range; 18-91); the median follow-up was 4.3 years (range; 0.1-17.8). A shorter overall survival (OS) was associated with the male gender, age ≥ 60 years, stage III/IV, performance status ≥ 2, bulky tumor ≥ 10 cm, and elevated LDH. CHOEP induction showed a better 5-year PFS (25.0% vs. 32.9%; p.001), and 5-year OS (65.6% vs. 47.6%; p.008) than CHOP. Auto-SCT compared to no SCT brought a 5-year OS of 49.2% vs. 59.5% (p.187). Auto-SCT did not influence the OS in low-risk or low-intermediate risk PTLs. The high-intermediate and high-risk IPIs displayed a worse 5-year OS in auto-SCT arm (17.7% vs.46.2%; p.049); however, 73.9% of the patients never received planned auto-SCT. Our population-based analysis showed the superiority of CHOEP over CHOP in first-line treatment. We confirm the 5-year OS of around 50% in PTLs undergoing auto-SCT. However, the intended auto-SCT could not be given in 73.9% of the high-risk PTLs.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ciclofosfamida/uso terapêutico , Progressão da Doença , Doxorrubicina/uso terapêutico , Etoposídeo/uso terapêutico , Feminino , Humanos , Linfoma de Células T Periférico/mortalidade , Linfoma de Células T Periférico/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prednisolona/uso terapêutico , Prednisona/uso terapêutico , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Transplante Autólogo , Vincristina/uso terapêutico
7.
Biol Blood Marrow Transplant ; 24(1): 64-70, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28942016

RESUMO

Autologous hematopoietic cell transplantation (AHCT) is curative for 60% of patients with relapsed or refractory Hodgkin lymphoma (R/R HL). A more precise assessment of the depth of remission before AHCT may help to identify patients likely to benefit from AHCT. We aimed to determine whether positron emission tomography (PET)-based quantitative parameters of total metabolic tumor volume (TMTV), total lesion glycolysis (TLG), and maximal standardized uptake volume (SUVmax) measured before AHCT predict progression-free survival (PFS) after transplant. Pretransplant PET/computed tomography images of 96 consecutive patients with R/R HL were analyzed. Median TMTV, TLG, and SUVmax were 7.97 cm3 (range, 1.3 to 102.1), 23.7 (range, 4.0 to 813.1), and 5.23 (range, 2.7 to 23.2). Two-year PFS in patients with high TMTV (TMTVhigh; more than median; n = 17) was only 12% (95% CI, 1% to 38%) compared with 53% (95% CI, 28% to 73%; P = .05) in patients with TMTVlow (lower or equal to median; n = 17) and 63% (95% CI, 50% to 74%) in 61 patients with no metabolically active tumor (TMTV0; P > .01). In concordance, high TLG (>19) and SUVmax (>4.9) predicted inferior 2-year PFS. In multivariate analysis patients with TMTVhigh had a 3.5-fold higher risk of treatment failure compared with TMTV0/TMTVlow (HR, 3.49; 95% CI, 1.75 to 6.93; P < .01). Deauville (D)-scores of 4 to 5 before AHCT predicted worse PFS compared with D-scores of 1 to 3 (HR, 3.7; 95% CI, 1.92 to 7.28; P < .01). Yet, TMTV and D-scores were disconcordant in 12 subjects; 9 patients in the D4 group with TMTVlow had 2-year PFS of 44% (95% CI, 14% to 72%), which was 2-fold higher than predicted by D4 score. In conclusion, in patients with R/R HL and PET-positive residual disease, TMTVhigh can identify very poor AHCT responders. Patients with TMTVlow, TLG, and SUVmax before AHCT have similar outcomes to those without metabolically active disease.


Assuntos
Transplante de Células-Tronco Hematopoéticas/mortalidade , Doença de Hodgkin/terapia , Tomografia por Emissão de Pósitrons/métodos , Valor Preditivo dos Testes , Adulto , Idoso , Feminino , Glicólise , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Transplante Autólogo/mortalidade , Resultado do Tratamento , Carga Tumoral
8.
Hematol Oncol ; 36(5): 773-778, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30129045

RESUMO

Rituximab maintenance (RM) prolongs survival of elderly patients with mantle cell lymphoma (MCL). Persistent minimal residual disease (MRD) after induction repeatedly correlated with shorter progression-free survival (PFS). However, none of the published studies analyzed patients treated with RM. The main purpose was to analyze prognostic significance of MRD in the elderly patients with newly diagnosed MCL treated according to the recently published observational trial protocol (alternation of R-CHOP and R-cytarabine, 3 + 3 cycles, GovTrial number NCT03054883) at the centers that implemented RM. Minimal residual disease was evaluated by a EuroMRD standardized real-time PCR approach after 3 and 6 cycles of the induction therapy. Prognostic significance of MRD was analyzed in a subcohort of patients treated at the centers that implemented RM as a standard approach. Bone marrow proved to be a significantly more sensitive source for MRD detection than peripheral blood. In either compartment MRD (positive versus negative) after 3 or 6 cycles of the induction therapy did not correlate with PFS. The observed loss of prognostic significance of MRD after the R-CHOP-based induction appears to be a consequence of RM immune control over the residual lymphoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma de Célula do Manto , Quimioterapia de Manutenção , Rituximab/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/administração & dosagem , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Linfoma de Célula do Manto/sangue , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Prednisona/administração & dosagem , Taxa de Sobrevida , Vincristina/administração & dosagem
9.
Hematol Oncol ; 36(1): 110-115, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29083050

RESUMO

Implementation of cytarabine into induction therapy became standard of care for younger patients with mantle cell lymphoma (MCL). On the basis of its beneficial impact, many centers incorporated cytarabine at lower doses also into first-line treatments of elderly patients. We conducted a multicenter observational study that prospectively analyzed safety and efficacy of alternating 3 + 3 cycles of R-CHOP and R-cytarabine for newly diagnosed transplant-ineligible MCL patients. A total of 73 patients were enrolled with median age 70 years. Most patients had intermediate (39.7%) and high-risk (50.7%) disease according to MCL international prognostic index. Rituximab maintenance was initiated in 58 patients. Overall response rate reached 89% by positron emission tomography-computed tomography, including 75.3% complete remissions. Two patients (2.7%) did not complete the induction therapy because of toxicity. Three patients (4.1%) were considered nonresponders, which led to therapy change before completion of induction. Estimated progression-free survival and overall survival were 51.3% and 68.6% at 4 years, respectively. Mantle cell lymphoma international prognostic index, bulky disease (≥ 5 cm), and achievement of positron emission tomography-negativity independently correlated with progression-free survival. Grade 3 to 4 hematologic and nonhematologic toxicity was documented in 48% and 20.5% patients, respectively. Alternation of R-CHOP and R-cytarabine represents feasible and very effective regimen for elderly/comorbid MCL patients. This study was registered at GovTrial (clinicaltrials.gov) NCT03054883.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/uso terapêutico , Linfoma de Célula do Manto/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/farmacologia , Anticorpos Monoclonais Murinos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Citarabina/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Feminino , Humanos , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Prednisona/farmacologia , Prednisona/uso terapêutico , Rituximab , Vincristina/farmacologia , Vincristina/uso terapêutico
11.
Ann Hematol ; 97(4): 669-678, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29318369

RESUMO

The aim of this study is to assess the incidence, risk factors, and outcome of biopsy-proven transformation in follicular lymphoma (FL) patients in the rituximab era. Transformation was analyzed in 1233 patients with initially diagnosed FL grades 1-3A, identified between 2002 and 2012 in the prospectively maintained Czech Lymphoma Study Group database. Only patients with histologically proven transformation (HT) were included. HT occurred in 58 cases at a median of 3.0 years from the initial FL diagnosis; the HT rate was 4% at 5 years. Transformation occurred most frequently at the first relapse (84% patients). Median OS from the HT was 2.5 years (95% CI 0.4-4.6) and 6-year OS with HT was shorter compared to all FLs (60 vs. 83.9%; 95% CI). A bulky tumor (≥ 10 cm), increased lactate dehydrogenase, age ≥ 60 years, and International Prognostic Index (intermediate/high risk), but not Follicular Lymphoma International Prognostic Index, were associated with transformation (p < 0.05). In the first line, 70% of patients received rituximab (including 36% rituximab maintenance), 57% CHOP-like regimens, and 2.6% of patients were treated with fludarabine-based therapy, whereas 11% of patients were watched only. The patients treated with R-CHOP in the first line (n = 591) showed the transformation rate at 5 years of 4.23% (95% CI 2.52-5.93); subsequent rituximab maintenance (n = 276) vs. observation (n = 153) was associated with a lower transformation rate (p.033; HR 3.29; CI 1.10-9.82). The transformation rate seems to be lower than in previous series, which may be influenced by broad use of rituximab, but prognosis of HT developed during therapy continues to be poor.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transformação Celular Neoplásica/efeitos dos fármacos , Linfoma Folicular/tratamento farmacológico , Rituximab/uso terapêutico , Adulto , Idoso , Antraciclinas/efeitos adversos , Antraciclinas/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biópsia , Transformação Celular Neoplásica/patologia , Estudos de Coortes , República Tcheca/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Linfoma Folicular/epidemiologia , Linfoma Folicular/patologia , Linfoma Folicular/prevenção & controle , Quimioterapia de Manutenção/efeitos adversos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Rituximab/efeitos adversos , Prevenção Secundária , Análise de Sobrevida
12.
Acta Haematol ; 134(4): 208-14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26066608

RESUMO

The programmed cell death pathway is involved in functional impairment of cytotoxic CD8+ T cells in chronic viral infection and in tumor immune evasion. The interaction of programmed cell death-1 (PD-1) with its ligand suppresses antitumor T cell function and stimulates the regulatory T cell population. The objectives were to investigate whether examining PD-1 expression in peripheral T cells of patients with chronic lymphocytic leukemia (CLL) reflected the disease phase and Binet stage and to compare the results with those in healthy volunteers. The study analyzed peripheral blood from previously untreated patients with CLL, patients with relapsed or refractory disease under treatment and healthy blood donors using flow cytometry. PD-1 expression in peripheral blood CD4+ and CD8+ cells was markedly different between disease stages and in comparison with healthy subjects. The highest numbers of both CD8+PD-1+ and CD4+PD-1+ cells were present in patients with relapsed/refractory disease. No distinct difference according to Binet stage was found. These facts support the hypothesis that tumor clones may switch effector CD8+ cells through the PD-1/PD-1L pathway into an immunotolerant state. The extent to which the mechanisms of antitumor immunity are influenced by enhanced expression of the programmed cell death depends on the disease phase but not Binet stage.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Regulação Leucêmica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/sangue , Proteínas de Neoplasias/sangue , Receptor de Morte Celular Programada 1/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Linfócito CD4 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Phys Chem Chem Phys ; 17(42): 28239-49, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25913178

RESUMO

Evolution of structure and local magnetic fields in (Fe(1-x)Co(x))76Mo8Cu1B15 (HITPERM) metallic glass ribbons with various amounts of Co (x = 0, 0.25, 0.5) were studied in situ using diffraction and nuclear forward scattering of synchrotron radiation. It was found that crystallization of all three glasses proceeds in two stages. In the first stage, bcc (Fe,Co) nanocrystals are formed, while in the second stage additional crystalline phases evolve. For all three glasses, the crystallization temperatures at the wheel side were found to be lower than at the air side of the ribbon. The crystallization temperatures were found to decrease with increasing Co content. The lattice parameters of the bcc nanocrystals decrease up to about 550 °C and then increase pointing to squeezing Mo atoms out of the nanograins or to interface effects between the nanocrystals and the glassy matrix. Nuclear forward scattering enabled separate evaluation of the contributions that stem from structurally different regions within the investigated samples including the newly formed nanocrystals and the residual amorphous matrix. Even minor Co content (x = 0.25) has a substantial effect not only upon the magnetic behaviour of the alloy but also upon its structure. Making use of hyperfine magnetic fields, it was possible to unveil structurally diverse positions of Fe atoms that reside in a nanocrystalline lattice with different numbers of Co nearest neighbours.

14.
Phys Chem Chem Phys ; 17(34): 21787-90, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26248056

RESUMO

Identification of unstable high-valent iron species in electron transfer reactions of ferrate(VI) (Fe(VI)O4(2-), Fe(VI)) has been an important challenge in advancing the understanding of the oxidative mechanisms of ferrates. This paper presents the first example of distinguishing various phases differing in the valence state of iron in the solid state reduction of Fe(VI) to Fe(III) oxides at 235 °C using hyperfine parameters, isomer shift and hyperfine magnetic field, obtained from nuclear forward scattering of synchrotron radiation (NFS). The NFS technique enables a fast data accumulation resulting in high time resolution of in situ experiments. The results suggest a reaction mechanism, involving Fe(V) and Fe(IV) species, in the thermal decomposition of K2FeO4 to KFeO2. The present study opens up an approach to exploring the unambiguous identification of Fe(VI), Fe(V), Fe(IV), and Fe(III) in electron-transfer reaction mechanisms of ferrates in solid and aqueous phase systems.


Assuntos
Ferro/química , Teoria Quântica , Espalhamento de Radiação , Síncrotrons , Transporte de Elétrons
16.
Cesk Patol ; 50(2): 95-9, 2014 Apr.
Artigo em Tcheco | MEDLINE | ID: mdl-24758506

RESUMO

The currently valid molecular genetic subclassification of patients with diffuse large B-cell lymphoma (DLBCL) into three prognostic subgroups based on expression profiling has been the objective of numerous genetic studies. In routine clinical practice, however, expression profiling technology remains unavailable for the most of centers. Apart from the technology, in some cases molecular genetic laboratories have problems obtaining high-quality material, i.e. fresh tissues, for RNA isolation to determine gene expression. One possibility is to determine the gene expression from RNA obtained by isolation from formalin-fixed, paraffin-embedded (FFPE) tissue. This pilot study aimed at isolating RNA from FFPE in patients diagnosed with DLBCL and verifying the potential use of such RNA for the expression analysis of 7 selected genes. Although the study showed that it is possible to isolate RNA and determine the expression of the selected genes from archival material, the values of relative expression of some genes in the set were too variable to be used for unambiguous prognostic classification. It was confirmed that retrospective analyses of selected genes may be performed with sufficient material obtained, and that properly archived blocks may be used for molecular biology analyses even after 8 years.


Assuntos
Perfilação da Expressão Gênica , Genes Neoplásicos , Linfoma Difuso de Grandes Células B/genética , RNA/isolamento & purificação , Formaldeído , Humanos , Parafina , Inclusão em Parafina , Projetos Piloto , Prognóstico , Estudos Retrospectivos , Manejo de Espécimes
18.
Blood Adv ; 7(23): 7295-7303, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-37729621

RESUMO

In the pre-novel agent era, the median postprogression overall survival (PPS) of patients with classic Hodgkin lymphoma (cHL) who progress after autologous stem cell transplant (ASCT) was 2 to 3 years. Recently, checkpoint inhibitors (CPI) and brentuximab vedotin (BV) have improved the depth and durability of response in this population. Here, we report the estimate of PPS in patients with relapsed cHL after ASCT in the era of CPI and BV. In this multicenter retrospective study of 15 participating institutions, adult patients with relapsed cHL after ASCT were included. Study objective was postprogression overall survival (PPS), defined as the time from posttransplant progression to death or last follow-up. Of 1158 patients who underwent ASCT, 367 had progressive disease. Median age was 34 years (range, 27-46) and 192 were male. Median PPS was 114.57 months (95% confidence interval [CI], 91-not achieved) or 9.5 years. In multivariate analysis, increasing age, progression within 6 months, and pre-ASCT positive positron emission tomography scan were associated with inferior PPS. When adjusted for these features, patients who received CPI, but not BV, as first treatment for post-ASCT progression had significantly higher PPS than the no CPI/no BV group (hazard ratio, 3.5; 95% CI, 1.6-7.8; P = .001). Receipt of allogeneic SCT (Allo-SCT) did not improve PPS. In the era of novel agents, progressive cHL after ASCT had long survival that compares favorably with previous reports. Patients who receive CPI as first treatment for progression had higher PPS. Receipt to Allo-SCT was not associated with PPS in this population.


Assuntos
Doença de Hodgkin , Imunoconjugados , Adulto , Feminino , Humanos , Masculino , Brentuximab Vedotin , Doença de Hodgkin/terapia , Estudos Retrospectivos , Transplante de Células-Tronco , Pessoa de Meia-Idade
20.
Front Oncol ; 12: 874462, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646641

RESUMO

Introduction: We analyzed the incidence, risk factors of central nervous system (CNS) relapse, and outcome of CNS involvement in patients with peripheral T-cell lymphomas (PTCL) from the Czech Lymphoma Study Group Registry NiHiL (Clinical Trial gov. NCT03199066). Materials and Methods: Out of 1,040 patients with PTCL, we identified 29 patients (2.79%) with CNS involvement: 2 patients with primary CNS T cell lymphoma, 11 patients with CNS and systemic disease at diagnosis, and 16 patients (1.54%) at CNS relapse. The most common histology with CNS disease was PTCL, not otherwise specified. Progression-free survival (PFS) was defined as the time interval from diagnosis to progression or death. PFS-2 was defined as the interval from the date of a new relapse until the next relapse. Results: Patients with testicular involvement received intrathecal prophylaxis with methotrexate. High-dose methotrexate-based treatment was administered in 44.8% of patients with CNS disease. Median follow-up was 71.3 months. The difference between the median PFS of 1,027 patients without initial CNS disease (32.6 months) and 11 patients with initial CNS and systemic disease (4.8 months) was significant (p = 0.04). The difference between the median PFS2 in CNS relapses (10.1 months) and 493 relapses outside of CNS (9.1 months) was not significant (p = 0.6). Risk factors for CNS relapses included the following: involvement of more than one extranodal site (p = 0.008), soft tissue involvement (p = 0.003), testicular involvement (p = 0.046), and the presence of B symptoms (p = 0.035). The difference between the median OS of 1,027 patients without initial CNS disease (46.0 months) and 11 patients with initial CNS and systemic disease (18.2 months) was significant (p = 0.02). The median OS2 in CNS relapses was 11.8 months and that in relapses outside of CNS was 21.3 months. CNS involvement was not associated with a significantly worse OS compared to relapsed/refractory patients without CNS involvement (p = 0.1). Conclusions: The incidence of CNS disease at the time of diagnosis and at relapse in PTCL is low and usually associated with other systemic involvement. The prognosis of PTCL with initial CNS involvement is significantly worse when compared to patients without CNS disease at diagnosis. The outcome of CNS relapse is comparable with relapsed PTCL outside of CNS. The optimal treatment is not defined yet.

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