RESUMO
Continuous attractors offer a unique class of solutions for storing continuous-valued variables in recurrent system states for indefinitely long time intervals. Unfortunately, continuous attractors suffer from severe structural instability in general--they are destroyed by most infinitesimal changes of the dynamical law that defines them. This fragility limits their utility especially in biological systems as their recurrent dynamics are subject to constant perturbations. We observe that the bifurcations from continuous attractors in theoretical neuroscience models display various structurally stable forms. Although their asymptotic behaviors to maintain memory are categorically distinct, their finite-time behaviors are similar. We build on the persistent manifold theory to explain the commonalities between bifurcations from and approximations of continuous attractors. Fast-slow decomposition analysis uncovers the persistent manifold that survives the seemingly destructive bifurcation. Moreover, recurrent neural networks trained on analog memory tasks display approximate continuous attractors with predicted slow manifold structures. Therefore, continuous attractors are functionally robust and remain useful as a universal analogy for understanding analog memory.
RESUMO
Although it is known that increasing age is associated with increased morbidity and mortality in allogeneic transplantation (allo-HSCT), individualization of the process may allow to perform it in progressively older patients.This study analyzed the outcome of 97 patients older than 60 years with a first allo-HSCT performed at our institution between 2011 and 2019.Median age was 66 years (range 60-79) and 15.4% were older than 70 years. The most frequent diagnosis was acute leukemia (50.5%), and 58.8% received a myeloablative conditioning. With a median follow-up of 33.9 months (range 7.9-111.5), at 3-years overall survival (OS) was 50%; progression-free survival (PFS), 46%; cumulative incidence of relapse, 22%; and non-relapse mortality (NRM), 32%. There were no significant differences in OS (p = 0.415), PFS (p = 0.691), cumulative incidence of relapse (p = 0.357) or NRM (p = 0.658) between patients of 60-64 years (n = 37), 65-69 (n = 45) and ≥ 70 years (n = 15). No differences were observed either depending on the intensity of the conditioning regimen in terms of OS (p = 0.858), PFS (p = 0.729), cumulative incidence of relapse (p = 0.416) or NRM (p = 0.270).In conclusion, older adults can safely and effectively undergo allo-HSCT with proper patient selection and individualized transplantation procedures.
Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Humanos , Idoso , Pessoa de Meia-Idade , Estudos de Viabilidade , Estudos Retrospectivos , Leucemia Mieloide Aguda/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Recidiva , Condicionamento Pré-Transplante/métodos , Doença Enxerto-Hospedeiro/etiologiaRESUMO
The Hospital at Home (HaH) model has been positioned as an appropriate therapeutic strategy for selected patients undergoing autologous hematopoietic stem cell transplantation (ASCT). This care model provides hospital-equivalent care, in terms of both quality and quantity, with medical and nursing staff that go to the patient's home. Here we describe our experience with a full HaH model for patients undergoing ASCT during the phase of aplasia. The patients met the eligibility criteria between January 1997 and December 2019 and were discharged from the hospital and admitted into the HaH-ASCT program on the same day they in which hematopoietic stem cells were infused. A total of 84 patients were included. The median patient age was 54 years (range, 16 to 74 years), and the median duration of participation in the HaH program was 17 days (range, 3 to 86 days). Only 10 of these patients (12%) required hospital readmission to the hematology department, 9 of them due to sepsis and 1 because of family care support claudication. Seventy-two patients (86%) experienced an episode of neutropenic fever during the HAH admission, with a median duration of 2 days (interquartile range [IQR], 1 to 11 days); all were treated with empiric i.v. antimicrobial therapy. Most patients (88%) presented with mucositis (44% with grade 3-4). Parenteral nutrition was administered in 26% of patients for a median of 6 days (IQR, 1 to 12 days). Most patients (94%) required at least 1 blood product transfusion at home. There was no transplantation-related mortality during the HaH-ASCT program or in the patients who were readmitted. With careful selection of patients and a comprehensive and well- experienced multidisciplinary team (doctors, nurses, and auxiliary nurses) in the HaH department and in close collaboration with the hematology department, complete at-home management of ASCT recipients immediately after transplantation is possible. This allows patients undergoing an aggressive procedure such as ASCT to remain in their own familiar environment, providing a better quality of life with a program that has demonstrated to be effective and safe, with a low incidence of complications and no associated mortality.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Qualidade de Vida , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Estudos de Viabilidade , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hospitalização , HospitaisRESUMO
Although case-control analyses have suggested an additive value with the association of clarithromycin to continuous lenalidomide and dexamethasone (Rd), there are not phase III trials confirming these results. In this phase III trial, 286 patients with MM ineligible for ASCT received Rd with or without clarithromycin until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS). With a median follow-up of 19 months (range, 0-54), no significant differences in the median PFS were observed between the two arms (C-Rd 23 months, Rd 29 months; HR 0.783, p = 0.14), despite a higher rate of complete response (CR) or better in the C-Rd group (22.6% vs 14.4%, p = 0.048). The most common G3-4 adverse events were neutropenia [12% vs 19%] and infections [30% vs 25%], similar between the two arms; however, the percentage of toxic deaths was higher in the C-Rd group (36/50 [72%] vs 22/40 [55%], p = 0.09). The addition of clarithromycin to Rd in untreated transplant ineligible MM patients does not improve PFS despite increasing the ≥CR rate due to the higher number of toxic deaths in the C-Rd arm. Side effects related to overexposure to steroids due to its delayed clearance induced by clarithromycin in this elderly population could explain these results. The trial was registered in clinicaltrials.gov with the name GEM-CLARIDEX: Ld vs BiRd and with the following identifier NCT02575144. The full trial protocol can be accessed from ClinicalTrials.gov. This study received financial support from BMS/Celgene.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Claritromicina/uso terapêutico , Dexametasona/uso terapêutico , Lenalidomida/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Claritromicina/efeitos adversos , Dexametasona/efeitos adversos , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Lenalidomida/efeitos adversos , Masculino , Transplante Autólogo , Resultado do TratamentoRESUMO
BACKGROUND: Several risk stratification models have been proposed in recent years for systemic mastocytosis but have not been directly compared. Here we designed and validated a risk stratification model for progression-free survival (PFS) and overall survival (OS) in systemic mastocytosis on the basis of all currently available prognostic factors, and compared its predictive capacity for patient outcome with that of other risk scores. METHODS: We did a retrospective prognostic modelling study based on patients diagnosed with systemic mastocytosis between March 1, 1983, and Oct 11, 2019. In a discovery cohort of 422 patients from centres of the Spanish Network on Mastocytosis (REMA), we evaluated previously identified, independent prognostic features for prognostic effect on PFS and OS by multivariable analysis, and designed a global prognostic score for mastocytosis (GPSM) aimed at predicting PFS (GPSM-PFS) and OS (GPSM-OS) by including only those variables that showed independent prognostic value (p<0·05). The GPSM scores were validated in an independent cohort of 853 patients from centres in Europe and the USA, and compared with pre-existing risk models in the total patient series (n=1275), with use of Harrells' concordance index (C-index) as a readout of the ability of each model to risk-stratify patients according to survival outcomes. FINDINGS: Our GPSM-PFS and GPSM-OS models were based on unique combinations of independent prognostic factors for PFS (platelet count ≤100â×â109 cells per L, serum ß2-microglobulin ≥2·5 µg/mL, and serum baseline tryptase ≥125 µg/L) and OS (haemoglobin ≤110 g/L, serum alkaline phosphatase ≥140 IU/L, and at least one mutation in SRSF2, ASXL1, RUNX1, or DNMT3A). The models showed clear discrimination between low-risk and high-risk patients in terms of worse PFS and OS prognoses in the discovery and validation cohorts, and further discrimination of intermediate-risk patients. The GPSM-PFS score was an accurate predictor of PFS in systemic mastocytosis (C-index 0·90 [95% CI 0·87-0·93], vs values ranging from 0·85 to 0·88 for pre-existing models), particularly in non-advanced systemic mastocytosis (C-index 0·85 [0·76-0·92], within the range for pre-existing models of 0·80 to 0·93). Additionally, the GPSM-OS score was able to accurately predict OS in the entire cohort (C-index 0·92 [0·89-0·94], vs 0·67 to 0·90 for pre-existing models), and showed some capacity to predict OS in advanced systemic mastocytosis (C-index 0·72 [0·66-0·78], vs 0·64 to 0·73 for pre-existing models). INTERPRETATION: All evaluated risk classifications predicted survival outcomes in systemic mastocytosis. The REMA-PFS and GPSM-PFS models for PFS, and the International Prognostic Scoring System for advanced systemic mastocytosis and GPSM-OS model for OS emerged as the most accurate models, indicating that robust prognostication might be prospectively achieved on the basis of biomarkers that are accessible in diagnostic laboratories worldwide. FUNDING: Carlos III Health Institute, European Regional Development Fund, Spanish Association of Mastocytosis and Related Diseases, Rare Diseases Strategy of the Spanish National Health System, Junta of Castile and León, Charles and Ann Johnson Foundation, Stanford Cancer Institute Innovation Fund, Austrian Science Fund.
Assuntos
Mastocitose Sistêmica/diagnóstico , Adulto , Idoso , Fosfatase Alcalina/sangue , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Hemoglobinas/análise , Humanos , Estimativa de Kaplan-Meier , Masculino , Mastocitose Sistêmica/mortalidade , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Intervalo Livre de Progressão , Proteínas Repressoras/genética , Estudos Retrospectivos , Fatores de Risco , Fatores de Processamento de Serina-Arginina/genéticaRESUMO
Follicular lymphoma does not usually present with associated paraneoplastic syndromes. We describe the case of a patient diagnosed with follicular lymphoma when investigating anaemia of chronic disease/inflammation and who, during her clinical course, developed peliosis hepatis. We have been able to confirm the similarity between the symptoms, the tumour's biology, the anaemia and peliosis, with the behaviour of endothelial growth factor, interleukins and iron metabolism disorders, which were normalised with treatment. To date, we have found no cases where peliosis has been described in this type of lymphoma.
RESUMO
Mycobacterium tuberculosis infections are uncommon complications in the haematopoietic stem cell post-transplant period. Most cases are reactivations of latent infections affecting the lung. We present an atypical case of isolated lymph node tuberculosis after an allogeneic haematopoietic stem cell transplantation, which highlights the importance of having a high suspicion index, even in non-endemic countries.
RESUMO
AIMS: Here we report two cases of follicular lymphoma that transformed to CD30 positive diffuse large B cell lymphoma and review the literature on this topic. RESULTS: The first case represents an example of early transformation of conventional low-grade follicular lymphoma to CD30-positive large B cell lymphoma. Immunoglobulin (Ig)H and cytogenetic identity was demonstrated between both components. High-dose and auto-stem cell transplant (SCT) was applied and complete response was achieved. The second case represents an example of d'emblee transformation of intrafollicular neoplasia to CD30-positive large B cell lymphoma. Immunoglobulin K deleting element (IgKde) and cytogenetic identity between both phases was demonstrated. The patient was in partial response after four cycles of rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP). CONCLUSIONS: CD30 expression was found to be associated in these cases to the transformation event and could be considered a therapeutic target to add to conventional immunochemotherapeutic regimens, even in combination with auto-SCT. We suggest looking for CD30 expression in transformed follicular lymphoma cases.