RESUMEN
Asciminib is a myristoyl site BCR::ABL1 inhibitor approved for chronic phase chronic myeloid leukaemia (CP-CML) patients failing ≥2 prior lines of therapy. The Australasian Leukaemia & Lymphoma Group (ALLG) conducted the ASCEND study to assess efficacy of asciminib for newly-diagnosed CP-CML. Patients commenced asciminib 40 mg twice daily (BID) and thereafter were managed according to molecular milestones. Patients with treatment failure, defined as BCR::ABL1 >10% (IS) at 3 or 6 months, or >1% at 12 or 18 months, received either imatinib, nilotinib or dasatinib in addition to asciminib. In patients with suboptimal response, defined as levels of 1-10% at 6 months, >0.1-1% at 12 months, or >0.01%-1% at 18 months, the asciminib dose was increased to 80 mg BID. With a median follow-up of 21 months (range 0-36), 82/101 patients continue asciminib. The most frequent reasons for treatment discontinuation were adverse events (6%), loss of response (4%) and withdrawn consent (5%). There were no deaths; one patient developed lymphoid blast crisis at 6 months. The co-primary endpoints were early molecular response (BCR::ABL1 ≤10% at 3 months), achieved in 93% (96% CI 86-97%), and major molecular response by 12 months achieved in 79%; (95% CI 69.7-86.8%), respectively. The cumulative incidence of MR4.5 was 53% by 24 months. One patient had 2 cerebrovascular events; no other arterial occlusive events were reported. Asciminib as frontline therapy in CP-CML produces high rates of molecular response with excellent tolerance and a low rate of discontinuation for toxicity. (ANZ Clinical Trials Registry ACTRN12620000851965).
RESUMEN
The mobility and bioavailability of phosphate in paddy soils are closely coupled to redox-driven Fe-mineral dynamics. However, the role of phosphate during Fe-mineral dissolution and transformations in soils remains unclear. Here, we investigated the transformations of ferrihydrite and lepidocrocite and the effects of phosphate pre-adsorbed to ferrihydrite during a 16-week field incubation in a flooded sandy rice paddy soil in Thailand. For the deployment of the synthetic Fe-minerals in the soil, the minerals were contained in mesh bags either in pure form or after mixing with soil material. In the latter case, the Fe-minerals were labeled with 57Fe to allow the tracing of minerals in the soil matrix with 57Fe Mössbauer spectroscopy. Porewater geochemical conditions were monitored, and changes in the Fe-mineral composition were analyzed using 57Fe Mössbauer spectroscopy and/or X-ray diffraction analysis. Reductive dissolution of ferrihydrite and lepidocrocite played a minor role in the pure mineral mesh bags, while in the 57Fe-mineral-soil mixes more than half of the minerals was dissolved. The pure ferrihydrite was transformed largely to goethite (82-85%), while ferrihydrite mixed with soil only resulted in 32% of all remaining 57Fe present as goethite after 16 weeks. In contrast, lepidocrocite was only transformed to 12% goethite when not mixed with soil, but 31% of all remaining 57Fe was found in goethite when it was mixed with soil. Adsorbed phosphate strongly hindered ferrihydrite transformation to other minerals, regardless of whether it was mixed with soil. Our results clearly demonstrate the influence of the complex soil matrix on Fe-mineral transformations in soils under field conditions and how phosphate can impact Fe oxyhydroxide dynamics under Fe reducing soil conditions.
Asunto(s)
Compuestos Férricos , Oryza , Fosfatos , Suelo , Oryza/química , Fosfatos/química , Suelo/química , Adsorción , Compuestos Férricos/química , Minerales/química , Espectroscopía de Mossbauer , Hierro/química , Oxidación-ReducciónRESUMEN
Asciminib is a novel allosteric STAMP (specifically targets the ABL myristoyl pocket) inhibitor of the BCR::ABL1 oncogene. Real-world clinical outcomes of patients with tyrosine kinase inhibitor (TKI)-resistant/intolerant chronic myeloid leukaemia (CML) in Australia on the Managed Access Programme for asciminib showed higher molecular responses for those with intolerance versus resistance ± intolerance to their last TKI. There remains a clinical need to improve outcomes in patients with CML who have resistance to multiple TKIs, especially in the ponatinib-pretreated cohort.
Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva , Inhibidores de Proteínas Quinasas , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Australia , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/uso terapéutico , Femenino , Resultado del Tratamiento , Anciano , Adulto , Resistencia a Antineoplásicos , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Antineoplásicos/uso terapéutico , Piridazinas/uso terapéutico , Anciano de 80 o más Años , Niacinamida/análogos & derivados , PirazolesRESUMEN
Infection and lymphopenia are established bendamustine-related complications. The relationship between lymphopenia severity and infection risk, and the role of antimicrobial prophylaxis, is not well described. This multicentre retrospective study analysed infection characteristics and antimicrobial prophylaxis in 302 bendamustine-treated indolent non-Hodgkin lymphoma patients. Lymphopenia (<1 × 109/L) was near universal and time to lymphocyte recovery correlated with cumulative bendamustine dose. No association between lymphopenia severity and duration with infection was observed. Infections occurred in 44% of patients (50% bacterial) with 27% hospitalised; 32% of infections occurred ≥3 months post bendamustine completion. Infection was associated with obinutuzumab and/or maintenance anti-CD20 therapy, prior therapy and advanced stage. Twenty-four opportunistic infections occurred in 21 patients: ten varicella zoster virus (VZV), seven herpes simplex virus (HSV), one cytomegalovirus, one progressive multifocal leucoencephalopathy, one nocardiosis, one Pneumocystis jiroveci pneumonia (PJP) and three other fungal infections. VZV/HSV and PJP prophylaxis were prescribed to 42% and 54% respectively. Fewer VZV/HSV infections occurred in patients receiving prophylaxis (HR 0.14, p = 0.061) while PJP prophylaxis was associated with reduced risk of bacterial infection (HR 0.48, p = 0.004). Our study demonstrates a significant infection risk regardless of lymphopenia severity and supports prophylaxis to mitigate the risk of early and delayed infections.
Asunto(s)
Clorhidrato de Bendamustina , Linfoma no Hodgkin , Linfopenia , Infecciones Oportunistas , Humanos , Clorhidrato de Bendamustina/uso terapéutico , Clorhidrato de Bendamustina/efectos adversos , Clorhidrato de Bendamustina/administración & dosificación , Masculino , Linfoma no Hodgkin/tratamiento farmacológico , Femenino , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Linfopenia/inducido químicamente , Adulto , Infecciones Oportunistas/prevención & control , Anciano de 80 o más Años , Profilaxis Antibiótica/métodos , Antineoplásicos Alquilantes/efectos adversos , Antineoplásicos Alquilantes/uso terapéuticoRESUMEN
The alunite supergroup of minerals contains several hydroxysulfate mineral phases that commonly occur in acidic natural and engineered environments. The main division of the mineral supergroup defines two minerals, jarosite and alunite, based on the relative structural occupancy by Al or Fe, respectively. However, intermediate members of the jarosite-alunite solid solution have not been extensively characterized, especially in the environment. Here, we link the mineral unit cell sizes measured by X-ray diffraction, peak shifts in Raman spectra, fitting parameters in Mössbauer spectroscopy, and elemental quantification by EDX spectroscopy to known amounts of Al substitution in two synthetic series of Al-substituted jarosite (up to Al-for-Fe substitution of 9.5%) and unknown Al substitution in a natural jarosite isolated from an acid sulfate soil. Strong correlations were observed between the Al substitution of the jarosite samples and unit cell size, position of several vibrational peaks in Raman spectroscopy, and the temperature of magnetic ordering. In addition, elemental mapping provided a robust way to characterize the Al content of jarosite. As the techniques were effective in quantifying the Al or Fe content of jarosite-alunite supergroup mineral samples, without the need for sample dissolution, the findings support the application of these spectroscopy techniques to characterize natural jarosite-alunite samples. Using these techniques, we demonstrate at least 5% Al-for-Fe substitution in a jarosite sample from an acid sulfate soil. Application to environmental samples is especially useful in cases where it is otherwise difficult to directly measure the Al content of a mineral sample or when Al-for-Fe substitution influences the spectral responses to substitution at other sites in the crystal structure.
RESUMEN
Budesonide is a 'non-absorbable' corticosteroid often used for gut graft versus host disease. Systemic exposure is usually minimal because of metabolism by cytochrome (CYP) 3A4 in enterocytes and the liver. However, concomitant use of posaconazole and voriconazole, inhibitors of CYP3A4 commonly used as antifungal prophylaxis in allograft patients receiving immunosuppression, can lead to substantial systemic steroid exposure. This paper describes a case of severe iatrogenic Cushing syndrome and tertiary adrenal insufficiency because of this interaction, highlighting the necessity for improved awareness of this phenomenon.
Asunto(s)
Insuficiencia Suprarrenal , Síndrome de Cushing , Humanos , Antifúngicos/efectos adversos , Budesonida/efectos adversos , Síndrome de Cushing/tratamiento farmacológico , Triazoles/efectos adversosRESUMEN
Arsenic trioxide is an essential component of therapy for acute promyelocytic leukaemia (APL) and is currently dosed on actual body weight with no upper limit. Arsenic-induced neurotoxicity is a well-recognised complication; however, there is uncertainty about its relationship to arsenic dose and obesity. We conducted a large multicentre retrospective study of 487 patients with APL treated with arsenic-based therapy across 23 sites in Australia from 2008 to 2023. The primary outcome was incidence of neurotoxicity, and secondary outcomes included relationship of neurotoxicity to obesity and cumulative arsenic dose. Any-grade neurotoxicity occurred in 113 (23%) patients, predominantly peripheral neuropathy (91%). Most events were grade 1-2 severity (85%), with grade 3 events in 12% and grade 4-5 in 3%. The incidence of neurotoxicity increased with BMI (non-obese: 16%, obesity class I: 25%, obesity class II-III: 41%; p < 0.001). On univariable analysis, obesity class I (OR 1.81, p = 0.036), obesity class II-III (OR 3.93, p < 0.001), weight >100 kg (OR 2.72, p < 0.001), daily arsenic trioxide dose >15 mg (OR 5.05, p < 0.001) and cumulative induction dose >500 mg (OR 3.95, p < 0.001) were all significantly associated with neurotoxicity. Obesity class II-III and induction dose >500 mg remained significant on multivariable analysis. Our study highlights the strong association between BMI, arsenic trioxide dose and neurotoxicity. Pre-emptive dose reductions should be considered for obese patients receiving high doses of arsenic.
Asunto(s)
Trióxido de Arsénico , Leucemia Promielocítica Aguda , Síndromes de Neurotoxicidad , Humanos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Estudios Retrospectivos , Trióxido de Arsénico/efectos adversos , Trióxido de Arsénico/administración & dosificación , Trióxido de Arsénico/uso terapéutico , Anciano , Síndromes de Neurotoxicidad/etiología , Síndromes de Neurotoxicidad/epidemiología , Obesidad/complicaciones , Australia/epidemiología , Arsénico/efectos adversos , Arsénico/toxicidad , Adulto Joven , Adolescente , Anciano de 80 o más AñosRESUMEN
The Philadelphia-negative myeloproliferative neoplasms (MPN) are a heterogeneous group of overlapping bone marrow disorders defined by characteristic peripheral blood counts and bone marrow morphological findings in conjunction with recurrent somatic mutations. The accurate diagnosis and subclassification of MPN relies upon careful reporting of bone marrow morphology combined with ancillary information in an integrated pathology report. This co-operative trial group study ALLG MPN01 (ANZCTR:12613000138785), led by the Australasian Leukaemia & Lymphoma Group (ALLG), aimed to describe the current approach to diagnosis of MPN in routine practice. Specifically, we assessed the frequency with which bone marrow biopsies were performed, and the adherence of reporting pathologists to recommendations contained in the revised 2016 WHO classification pertaining to MPN. We reviewed the diagnosis of 152 patients from eight institutions who were enrolled in a national MPN registry of the ALLG between 2010 and 2016. The ALLG MPN01 registry is now closed to recruitment. Key features were extracted from pathology reports provided to the registry. Bone marrow biopsies were performed in 112/152 cases (74%). The pathological information entered was concordant with the stated clinical diagnosis in 75/112 cases (67%). The main reasons for discordant results were incomplete descriptions of megakaryocyte topography and morphology, inconsistent grading of reticulin fibrosis, and failure to integrate the available morphological and ancillary clinicopathological information. In this retrospective audit, 26% of MPN patients did not undergo a diagnostic bone marrow biopsy. In those who did, the specific MPN subtype may not have been reported correctly in 33% of cases, as evidenced by inconsistent features reported or insufficient information to assess. A more standardised approach to bone marrow reporting is required to ensure accuracy of MPN diagnoses and consistent reporting to cancer registries and clinical trials.
Asunto(s)
Leucemia , Linfoma , Trastornos Mieloproliferativos , Humanos , Biopsia/métodos , Médula Ósea/patología , Leucemia/patología , Linfoma/patología , Trastornos Mieloproliferativos/patología , Estudios Retrospectivos , Ensayos Clínicos como AsuntoRESUMEN
Iron (Fe) oxyhydroxides can be reductively dissolved or transformed under Fe reducing conditions, affecting mineral crystallinity and the sorption capacity for other elements. However, the pathways and rates at which these processes occur under natural soil conditions are still poorly understood. Here, we studied Fe oxyhydroxide transformations during reduction-oxidation cycles by incubating mesh bags containing ferrihydrite or lepidocrocite in paddy soil mesocosms for up to 12 weeks. To investigate the influence of close contact with the soil matrix, mesh bags were either filled with pure Fe minerals or with soil mixed with 57Fe-labeled Fe minerals. Three cycles of flooding (3 weeks) and drainage (1 week) were applied to induce soil redox cycles. The Fe mineral composition was analyzed with Fe K-edge X-ray absorption fine structure spectroscopy, X-ray diffraction analysis and/or 57Fe Mössbauer spectroscopy. Ferrihydrite and lepidocrocite in mesh bags without soil transformed to magnetite and/or goethite, likely catalyzed by Fe(II) released to the pore water by microbial Fe reduction in the surrounding soil. In contrast, 57Fe-ferrihydrite in mineral-soil mixes transformed to a highly disordered mixed-valence Fe(II)-Fe(III) phase, suggesting hindered transformation to crystalline Fe minerals. The 57Fe-lepidocrocite transformed to goethite and small amounts of the highly disordered Fe phase. The extent of reductive dissolution of minerals in 57Fe-mineral-soil mixes during anoxic periods increased with every redox cycle, while ferrihydrite and lepidocrocite precipitated during oxic periods. The results demonstrate that the soil matrix strongly impacts Fe oxyhydroxide transformations when minerals are in close spatial association or direct contact with other soil components. This can lead to highly disordered and reactive Fe phases from ferrihydrite rather than crystalline mineral products and promoted goethite formation from lepidocrocite.
Asunto(s)
Compuestos Férricos , Minerales , Compuestos Férricos/química , Minerales/química , Oxidación-Reducción , Óxido FerrosoférricoRESUMEN
The phase 3 SELENE study evaluated ibrutinib + chemoimmunotherapy (CIT; bendamustine and rituximab [BR]; or rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone [R-CHOP]) for patients with relapsed/refractory (R/R) follicular lymphoma (FL) or marginal zone lymphoma (MZL). Adult patients who had received ≥1 prior line of CIT were randomized 1:1 to oral ibrutinib (560 mg) or placebo daily, plus 6 cycles of BR/R-CHOP. The primary end point was investigator-assessed progression-free survival (PFS). Overall, 403 patients were randomized to ibrutinib + CIT (n = 202) or placebo + CIT (n = 201). Most patients received BR (90.3%) and had FL (86.1%). With a median follow-up of 84 months, median PFS was 40.5 months in the ibrutinib + CIT arm and 23.8 months in the placebo + CIT arm (hazard ratio [HR], 0.806; 95% confidence interval [CI], 0.626-1.037; P = .0922). Median overall survival was not reached in either arm (HR, 0.980; 95% CI, 0.686-1.400). Grade ≥3 treatment-emergent adverse events (TEAEs) were reported in 85.6% and 75.4% of patients in the ibrutinib + CIT and placebo + CIT arms, respectively. In each arm, 13 patients had TEAEs leading to death. The addition of ibrutinib to CIT did not significantly improve PFS compared with placebo + CIT. The safety profile was consistent with known profiles of ibrutinib and CIT. This trial was registered at www.clinicaltrials.gov as #NCT01974440.
Asunto(s)
Linfoma de Células B de la Zona Marginal , Linfoma Folicular , Adulto , Humanos , Rituximab/efectos adversos , Clorhidrato de Bendamustina/uso terapéutico , Piperidinas/uso terapéutico , Vincristina/efectos adversos , Ciclofosfamida/efectos adversos , Prednisona/efectos adversos , Doxorrubicina/efectos adversos , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Linfoma Folicular/tratamiento farmacológicoRESUMEN
Safe outpatient management of acute leukaemia consolidation cycles may enable substantial savings in admission costs. Safety involves the prompt administration of antibiotics in patients with neutropenic fever. Our unit in a metropolitan tertiary referral hospital analysed a cohort of patients spanning a 10-year period, with two key observations: (i) a high proportion of patients living a substantial distance from hospital and (ii) the high incidence and generally prompt onset of fever after severe neutropenia, suggesting this broad applicability of this approach is unfeasible without addressing travel issues and potentially reducing and/or delaying neutropenic fever with prophylactic antibiotics.
Asunto(s)
Leucemia Mieloide Aguda , Neutropenia , Humanos , Pacientes Ambulatorios , Quimioterapia de Consolidación , Readmisión del Paciente , Leucemia Mieloide Aguda/tratamiento farmacológico , Antibacterianos , Neutropenia/inducido químicamente , Neutropenia/epidemiología , Políticas , Centros de Atención TerciariaRESUMEN
Despite the recent publication of calreticulin (CALR)-mutated essential thrombocythemia (ET) management guidelines by the European Leukemia Net (ELN), there remains a paucity of data regarding the optimal way to manage this condition. To determine practice around Australia, we constructed a survey asking investigation and treatment questions in a hypothetical case of a young woman with CALR-mutated ET and subsequent progression to myelofibrosis. 51 of 88 hematologists replied. The responses demonstrated significant heterogeneity in specific issues such as the use of aspirin, when to initiate cytoreduction, the preferred type of cytoreduction, and platelet targets. These observations support the ELN acknowledgment that a strong evidence base for many management recommendations is lacking in this disease, and that substantial further research is needed.
Asunto(s)
Leucemia , Mielofibrosis Primaria , Trombocitemia Esencial , Femenino , Humanos , Mielofibrosis Primaria/diagnóstico , Mielofibrosis Primaria/genética , Mielofibrosis Primaria/terapia , Trombocitemia Esencial/diagnóstico , Trombocitemia Esencial/genética , Trombocitemia Esencial/terapia , Calreticulina/genética , Plaquetas , Mutación , Janus Quinasa 2/genéticaRESUMEN
Importance: Autologous hematopoietic stem cell transplant (AHSCT) is available for treatment of highly active multiple sclerosis (MS). Objective: To compare the effectiveness of AHSCT vs fingolimod, natalizumab, and ocrelizumab in relapsing-remitting MS by emulating pairwise trials. Design, Setting, and Participants: This comparative treatment effectiveness study included 6 specialist MS centers with AHSCT programs and international MSBase registry between 2006 and 2021. The study included patients with relapsing-remitting MS treated with AHSCT, fingolimod, natalizumab, or ocrelizumab with 2 or more years study follow-up including 2 or more disability assessments. Patients were matched on a propensity score derived from clinical and demographic characteristics. Exposure: AHSCT vs fingolimod, natalizumab, or ocrelizumab. Main outcomes: Pairwise-censored groups were compared on annualized relapse rates (ARR) and freedom from relapses and 6-month confirmed Expanded Disability Status Scale (EDSS) score worsening and improvement. Results: Of 4915 individuals, 167 were treated with AHSCT; 2558, fingolimod; 1490, natalizumab; and 700, ocrelizumab. The prematch AHSCT cohort was younger and with greater disability than the fingolimod, natalizumab, and ocrelizumab cohorts; the matched groups were closely aligned. The proportion of women ranged from 65% to 70%, and the mean (SD) age ranged from 35.3 (9.4) to 37.1 (10.6) years. The mean (SD) disease duration ranged from 7.9 (5.6) to 8.7 (5.4) years, EDSS score ranged from 3.5 (1.6) to 3.9 (1.9), and frequency of relapses ranged from 0.77 (0.94) to 0.86 (0.89) in the preceding year. Compared with the fingolimod group (769 [30.0%]), AHSCT (144 [86.2%]) was associated with fewer relapses (ARR: mean [SD], 0.09 [0.30] vs 0.20 [0.44]), similar risk of disability worsening (hazard ratio [HR], 1.70; 95% CI, 0.91-3.17), and higher chance of disability improvement (HR, 2.70; 95% CI, 1.71-4.26) over 5 years. Compared with natalizumab (730 [49.0%]), AHSCT (146 [87.4%]) was associated with marginally lower ARR (mean [SD], 0.08 [0.31] vs 0.10 [0.34]), similar risk of disability worsening (HR, 1.06; 95% CI, 0.54-2.09), and higher chance of disability improvement (HR, 2.68; 95% CI, 1.72-4.18) over 5 years. AHSCT (110 [65.9%]) and ocrelizumab (343 [49.0%]) were associated with similar ARR (mean [SD], 0.09 [0.34] vs 0.06 [0.32]), disability worsening (HR, 1.77; 95% CI, 0.61-5.08), and disability improvement (HR, 1.37; 95% CI, 0.66-2.82) over 3 years. AHSCT-related mortality occurred in 1 of 159 patients (0.6%). Conclusion: In this study, the association of AHSCT with preventing relapses and facilitating recovery from disability was considerably superior to fingolimod and marginally superior to natalizumab. This study did not find evidence for difference in the effectiveness of AHSCT and ocrelizumab over a shorter available follow-up time.
Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Femenino , Humanos , Adulto , Natalizumab/uso terapéutico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Clorhidrato de Fingolimod/uso terapéuticoRESUMEN
The phase III GALLIUM trial assessed the safety and efficacy of obinutuzumab-based versus rituximab-based immunochemotherapy in patients with previously untreated follicular lymphoma (FL) or marginal zone lymphoma (MZL). At the primary analysis, the trial met its primary end point, demonstrating improvement in investigator-assessed progression-free survival (PFS) with obinutuzumab-based versus rituximab-based immunochemotherapy in patients with FL. We report the results of the final analysis in the FL population, with an additional exploratory analysis in the MZL subgroup. Overall, 1202 patients with FL were randomized 1:1 to obinutuzumab- or rituximab-based immunochemotherapy followed by maintenance with the same antibody for up to 2 years. After a median 7.9 (range, 0.0-9.8) years of follow-up, PFS remained improved with obinutuzumab- versus rituximab-based immunochemotherapy, with 7-year PFS rates of 63.4% versus 55.7% (P = 0.006). Time-to-next antilymphoma treatment was also improved (74.1% versus 65.4% of patients had not started their next antilymphoma treatment at 7 y; P = 0.001). Overall survival was similar between the arms (88.5% versus 87.2%; P = 0.36). Irrespective of the treatment received, PFS and OS were higher in patients with a complete molecular response (CMR) versus those with no CMR (P < 0.001). Serious adverse events were reported in 48.9% and 43.4% of patients in the obinutuzumab and rituximab arms, respectively; there was no difference in the rate of fatal adverse events (4.4% and 4.5%, respectively). No new safety signals were reported. These data demonstrate the long-term benefit of obinutuzumab-based immunochemotherapy and confirm its role as a standard-of-care for the first-line treatment of advanced-stage FL, taking into account patient characteristics and safety considerations.
RESUMEN
Iron minerals in soils and sediments play important roles in many biogeochemical processes and therefore influence the cycling of major and trace elements and the fate of pollutants in the environment. However, the kinetics and pathways of Fe mineral recrystallization and transformation processes under environmentally relevant conditions are still elusive. Here, we present a novel approach enabling us to follow the transformations of Fe minerals added to soils or sediments in close spatial association with complex solid matrices including other minerals, organic matter, and microorganisms. Minerals enriched with the stable isotope 57Fe are mixed with soil or sediment, and changes in Fe speciation are subsequently studied by 57Fe Mössbauer spectroscopy, which exclusively detects 57Fe. In this study, 57Fe-labeled ferrihydrite was synthesized, mixed with four soils differing in chemical and physical properties, and incubated for 12+ weeks under anoxic conditions. Our results reveal that the formation of crystalline Fe(III)(oxyhydr)oxides such as lepidocrocite and goethite was strongly suppressed, and instead formation of a green rust-like phase was observed in all soils. These results contrast those from Fe(II)-catalyzed ferrihydrite transformation experiments, where formation of lepidocrocite, goethite, and/or magnetite often occurs. The presented approach allows control over the composition and crystallinity of the initial Fe mineral, and it can be easily adapted to other experimental setups or Fe minerals. It thus offers great potential for future investigations of Fe mineral transformations in situ under environmentally relevant conditions, in both the laboratory and the field.
Asunto(s)
Compuestos Férricos , Hierro , Compuestos Férricos/química , Suelo , Espectroscopía de Mossbauer , Oxidación-Reducción , Minerales/químicaRESUMEN
We evaluated immune cell subsets in patients with chronic lymphocytic leukemia (CLL) who received first-line therapy with 3 cycles of ibrutinib then 13 cycles of ibrutinib plus venetoclax in the minimal residual disease (MRD) cohort of the CAPTIVATE study (NCT02910583). Patients with Confirmed undetectable MRD (uMRD) were randomly assigned to placebo or ibrutinib groups; patients without Confirmed uMRD were randomly assigned to ibrutinib or ibrutinib plus venetoclax groups. We compared immune cell subsets in samples collected at 7 time points with age-matched healthy donors. CLL cells decreased within 3 cycles after venetoclax initiation; from cycle 16 onward, levels were similar to healthy donor levels (HDL; ≤0.8 cells per µL) in patients with Confirmed uMRD and slightly above HDL in patients without Confirmed uMRD. By 4 months after cycle 16, normal B cells had recovered to HDL in patients randomly assigned to placebo. Regardless of randomized treatment, abnormal counts of T cells, classical monocytes, and conventional dendritic cells recovered to HDL within 6 months (median change from baseline -49%, +101%, and +91%, respectively); plasmacytoid dendritic cells recovered by cycle 20 (+598%). Infections generally decreased over time regardless of randomized treatment and were numerically lowest in patients randomly assigned to placebo within 12 months after cycle 16. Sustained elimination of CLL cells and recovery of normal B cells were confirmed in samples from patients treated with fixed-duration ibrutinib plus venetoclax in the GLOW study (NCT03462719). These results demonstrate promising evidence of restoration of normal blood immune composition with ibrutinib plus venetoclax.
Asunto(s)
Reconstitución Inmune , Leucemia Linfocítica Crónica de Células B , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Piperidinas/uso terapéuticoRESUMEN
Since the recognition of BRAF V600E mutations in the majority of cases of hairy cell leukaemia, Erdheim-Chester disease and Langerhans cell histiocytosis, the targeted oral kinase inhibitors dabrafenib and vemurafenib have been adapted for their treatment. Like other targeted agents, these drugs produce high response rates and predictable but unique side effects. Physician familiarity is essential for the effective use of these agents. We review the Australian experience of BRAF/MEK inhibitor therapy in these rare haematological cancers.
Asunto(s)
Neoplasias Hematológicas , Proteínas Proto-Oncogénicas B-raf , Humanos , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Neoplasias Hematológicas/tratamiento farmacológico , Australia , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Vemurafenib/uso terapéutico , Histiocitosis de Células de Langerhans/tratamiento farmacológico , Enfermedad de Erdheim-Chester/tratamiento farmacológico , Leucemia de Células Pilosas/tratamiento farmacológicoRESUMEN
Currently there are no guidelines on a safe neutrophil count(ANC) for intravenous antibiotic(IVAB) cessation and hospital discharge in patients recovering after febrile neutropenia(FN). We assessed the safety in selected patients after recent FN of prompt IVAB cessation and hospital discharge. Safety was defined as no fever recurrence after IVAB cessation and readmission in the 10-days post-discharge for infections.A retrospective, single center audit conducted on 92 adult hematology patients admitted with de novo acute myeloid leukemia (AML) for intensive chemotherapy or for an autograft. Most admissions (n = 128/141;91%) were complicated by FN. Half of FN episodes ceased IVAB promptly with a median(range) ANC of 0.6(0.1-4.9x109/L); none of these episodes had recurrent fever requiring IVAB resumption. Prompt discharge occurred in 45% overall. Subsequent unplanned readmission rates were low.In afebrile, stable AML and autograft patients without medico-social barriers to discharge, IVAB can be ceased and hospital discharges safely done ≤24h of ANC ≥ 0.2x109/L.