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1.
Blood ; 139(24): 3546-3557, 2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-35286378

RESUMEN

Older patients with acute myeloid leukemia (AML) have high relapse risk and poor survival after allogeneic hematopoietic cell transplantation (HCT). Younger patients may receive myeloablative conditioning to mitigate relapse risk associated with high-risk genetics or measurable residual disease (MRD), but older adults typically receive reduced-intensity conditioning (RIC) to limit toxicity. To identify factors that drive HCT outcomes in older patients, we performed targeted mutational analysis (variant allele fraction ≥2%) on diagnostic samples from 295 patients with AML aged ≥60 years who underwent HCT in first complete remission, 91% of whom received RIC, and targeted duplex sequencing at remission in a subset comprising 192 patients. In a multivariable model for leukemia-free survival (LFS) including baseline genetic and clinical variables, we defined patients with low (3-year LFS, 85%), intermediate (55%), high (35%), and very high (7%) risk. Before HCT, 79.7% of patients had persistent baseline mutations, including 18.3% with only DNMT3A or TET2 (DT) mutations and 61.4% with other mutations (MRD positive). In univariable analysis, MRD positivity was associated with increased relapse and inferior LFS, compared with DT and MRD-negative mutations. However, in a multivariable model accounting for baseline risk, MRD positivity had no independent impact on LFS, most likely because of its significant association with diagnostic genetic characteristics, including MDS-associated gene mutations, TP53 mutations, and high-risk karyotype. In summary, molecular associations with MRD positivity and transplant outcomes in older patients with AML are driven primarily by baseline genetics, not by mutations present in remission. In this group of patients, where high-intensity conditioning carries substantial risk of toxicity, alternative approaches to mitigating MRD-associated relapse risk are needed.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Anciano , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Recurrencia , Estudios Retrospectivos , Acondicionamiento Pretrasplante , Trasplante Homólogo
2.
Br J Haematol ; 203(5): 840-851, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37614192

RESUMEN

Comorbidity assessment before allogeneic haematopoietic cell transplantation (allo-HCT) is essential for estimating non-relapse mortality (NRM) risk. We previously developed the Simplified Comorbidity Index (SCI), which captures a small number of 'high-yield' comorbidities and older age. The SCI was predictive of NRM in myeloablative CD34-selected allo-HCT. Here, we evaluated the SCI in a single-centre cohort of 327 patients receiving reduced-intensity conditioning followed by unmanipulated allografts from HLA-matched donors. Among the SCI factors, age above 60, mild renal impairment, moderate pulmonary disease and cardiac disease were most frequent. SCI scores ranged from 0 to 8, with 39%, 20%, 20% and 21% having scores of 0-1, 2, 3 and ≥4 respectively. Corresponding cumulative incidences of 3-year NRM were 11%, 16%, 22% and 27%; p = 0.03. In multivariable models, higher SCI scores were associated with incremental risks of all-cause mortality and NRM. The SCI had an area under the receiver operating characteristic curve of 65.9%, 64.1% and 62.9% for predicting 1-, 2- and 3-year NRM versus 58.4%, 60.4% and 59.3% with the haematopoietic cell transplantation comorbidity index. These results demonstrate for the first time that the SCI is predictive of NRM in patients receiving allo-HCT from HLA-matched donors after reduced-intensity conditioning.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Donantes de Tejidos , Humanos , Comorbilidad , Trasplante de Células Madre Hematopoyéticas/métodos , Recurrencia , Estudios Retrospectivos , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo/métodos , Mortalidad
3.
N Engl J Med ; 382(9): 822-834, 2020 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-32101664

RESUMEN

BACKGROUND: Relationships between microbiota composition and clinical outcomes after allogeneic hematopoietic-cell transplantation have been described in single-center studies. Geographic variations in the composition of human microbial communities and differences in clinical practices across institutions raise the question of whether these associations are generalizable. METHODS: The microbiota composition of fecal samples obtained from patients who were undergoing allogeneic hematopoietic-cell transplantation at four centers was profiled by means of 16S ribosomal RNA gene sequencing. In an observational study, we examined associations between microbiota diversity and mortality using Cox proportional-hazards analysis. For stratification of the cohorts into higher- and lower-diversity groups, the median diversity value that was observed at the study center in New York was used. In the analysis of independent cohorts, the New York center was cohort 1, and three centers in Germany, Japan, and North Carolina composed cohort 2. Cohort 1 and subgroups within it were analyzed for additional outcomes, including transplantation-related death. RESULTS: We profiled 8767 fecal samples obtained from 1362 patients undergoing allogeneic hematopoietic-cell transplantation at the four centers. We observed patterns of microbiota disruption characterized by loss of diversity and domination by single taxa. Higher diversity of intestinal microbiota was associated with a lower risk of death in independent cohorts (cohort 1: 104 deaths among 354 patients in the higher-diversity group vs. 136 deaths among 350 patients in the lower-diversity group; adjusted hazard ratio, 0.71; 95% confidence interval [CI], 0.55 to 0.92; cohort 2: 18 deaths among 87 patients in the higher-diversity group vs. 35 deaths among 92 patients in the lower-diversity group; adjusted hazard ratio, 0.49; 95% CI, 0.27 to 0.90). Subgroup analyses identified an association between lower intestinal diversity and higher risks of transplantation-related death and death attributable to graft-versus-host disease. Baseline samples obtained before transplantation already showed evidence of microbiome disruption, and lower diversity before transplantation was associated with poor survival. CONCLUSIONS: Patterns of microbiota disruption during allogeneic hematopoietic-cell transplantation were similar across transplantation centers and geographic locations; patterns were characterized by loss of diversity and domination by single taxa. Higher diversity of intestinal microbiota at the time of neutrophil engraftment was associated with lower mortality. (Funded by the National Cancer Institute and others.).


Asunto(s)
Microbioma Gastrointestinal , Trasplante de Células Madre Hematopoyéticas/mortalidad , Adulto , Biodiversidad , Heces/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Análisis de Supervivencia , Trasplante Homólogo/mortalidad
4.
Cancer Immunol Immunother ; 72(4): 815-826, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36063172

RESUMEN

Immune suppressive factors of the tumor microenvironment (TME) undermine viability and exhaust the activities of the intratumoral cytotoxic CD8 + T lymphocytes (CTL) thereby evading anti-tumor immunity and decreasing the benefits of immune therapies. To counteract this suppression and improve the efficacy of therapeutic regimens, it is important to identify and understand the critical regulators within CD8 + T cells that respond to TME stress and tumor-derived factors. Here we investigated the regulation and importance of activating transcription factor-4 (ATF4) in CTL using a novel Atf4ΔCD8 mouse model lacking ATF4 specifically in CD8 + cells. Induction of ATF4 in CD8 + T cells occurred in response to antigenic stimulation and was further increased by exposure to tumor-derived factors and TME conditions. Under these conditions, ATF4 played a critical role in the maintenance of survival and activities of CD8 + T cells. Conversely, selective ablation of ATF4 in CD8 + T cells in mice rendered these Atf4ΔCD8 hosts prone to accelerated growth of implanted tumors. Intratumoral ATF4-deficient CD8 + T cells were under-represented compared to wild-type counterparts and exhibited impaired activation and increased apoptosis. These findings identify ATF4 as an important regulator of viability and activity of CD8 + T cells in the TME and argue for caution in using agents that could undermine these functions of ATF4 for anti-cancer therapies.


Asunto(s)
Linfocitos Infiltrantes de Tumor , Neoplasias , Ratones , Animales , Linfocitos T CD8-positivos , Linfocitos T Citotóxicos , Factores de Transcripción Activadores , Microambiente Tumoral
5.
Am J Hematol ; 98(12): 1869-1876, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37688521

RESUMEN

Allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative treatment for patients with acute leukemia. Despite this, studies have shown that only a minority of patients ultimately proceed to allo-HCT. The primary objective of this prospective, observational study was to identify the rate of allo-HCT in patients for whom it was recommended, and reasons why patients deemed appropriate and eligible for HCT did not subsequently undergo transplant. Between April 2016 and April 2021, adult patients with newly diagnosed or relapsed/refractory acute leukemia were enrolled at the time of induction/reinduction therapy. Initial transplantation workup and allo-HCT recommendations were made during the early phase of induction/reinduction. Of the 307 enrolled patients, allo-HCT was recommended to 85% (n = 259), of whom 66% (n = 170) underwent transplant. Donor sources comprised 54% human leukocyte antigen (HLA)-matched unrelated donors, 20% HLA-matched sibling donors and HLA-mismatched graft sources with 15% umbilical cord blood units, 8% HLA-mismatched unrelated donors, and 4% HLA-haploidentical donors. The most common reason for transplant disqualification in the 89 patients in whom it was initially recommended was persistent/relapsed disease (70%), followed by early patient death (10%). In this prospective study, we report a high allo-HCT rate, which may be due to early transplant referral and workup. The main allo-HCT barrier was disease control, followed by early patient death. With the increasing availability of HLA-mismatched graft sources, the lack of donor availability was not a transplant barrier. Further development of novel transplant strategies for patients not achieving remission and improvements in induction regimens could result in increased allo-HCT utilization.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Adulto , Humanos , Estudios Prospectivos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Donante no Emparentado , Trasplante Homólogo , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/etiología , Enfermedad Aguda , Antígenos HLA , Enfermedad Injerto contra Huésped/etiología , Estudios Retrospectivos
6.
Am J Hematol ; 98(1): 79-89, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36251406

RESUMEN

Measurable residual disease (MRD) is a powerful prognostic factor in acute myeloid leukemia (AML). However, pre-treatment molecular predictors of immunophenotypic MRD clearance remain unclear. We analyzed a dataset of 211 patients with pre-treatment next-generation sequencing who received induction chemotherapy and had MRD assessed by serial immunophenotypic monitoring after induction, subsequent therapy, and allogeneic stem cell transplant (allo-SCT). Induction chemotherapy led to MRD- remission, MRD+ remission, and persistent disease in 35%, 27%, and 38% of patients, respectively. With subsequent therapy, 34% of patients with MRD+ and 26% of patients with persistent disease converted to MRD-. Mutations in CEBPA, NRAS, KRAS, and NPM1 predicted high rates of MRD- remission, while mutations in TP53, SF3B1, ASXL1, and RUNX1 and karyotypic abnormalities including inv (3), monosomy 5 or 7 predicted low rates of MRD- remission. Patients with fewer individual clones were more likely to achieve MRD- remission. Among 132 patients who underwent allo-SCT, outcomes were favorable whether patients achieved early MRD- after induction or later MRD- after subsequent therapy prior to allo-SCT. As MRD conversion with chemotherapy prior to allo-SCT is rarely achieved in patients with specific baseline mutational patterns and high clone numbers, upfront inclusion of these patients into clinical trials should be considered.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Humanos , Pronóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Trasplante de Células Madre , Inducción de Remisión , Trasplante Homólogo , Neoplasia Residual/genética
7.
J Infect Dis ; 225(3): 453-464, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34390240

RESUMEN

BACKGROUND: We examined the correlation between persistent human herpesvirus 6 (HHV-6) DNAemia (p-HHV-6) and absolute lymphocyte count (ALC), platelet count (PLT), and all-cause mortality by 1 year after ex vivo T-cell-depleted (TCD) hematopoietic cell transplant (HCT). METHODS: We analyzed a cohort of adult TCD HCT recipients during 2012-2016 prospectively monitored for plasma HHV-6 by quantitative polymerase chain reaction from day +14 post-HCT through day +100 (D+100). p-HHV-6 was defined as ≥2 consecutive values of ≥500 copies/mL by D+100. PLT and ALC were compared between patients with and without p-HHV-6 using generalized estimating equations (GEE). Multivariable Cox proportional hazard models (PH) were used to identify the impact of p-HHV-6 on 1 year mortality. RESULTS: Of 312 patients, 83 (27%) had p-HHV-6 by D+100. p-HHV-6 was associated with lower ALC and PLT in the first year post-HCT. In multivariable models, p-HHV-6 was associated with higher mortality by 1 year post-HCT (adjusted hazard ratio, 2.97 [95% confidence interval, 1.62-5.47]; P = .0005), after adjusting for age, antiviral treatment, and ALC at D+100. CONCLUSIONS: p-HHV-6 was associated with lower ALC and PLT in the first year post-HCT. p-HHV-6 was an independent predictor of mortality in the first year after TCD HCT.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Herpesvirus Humano 6 , Infecciones por Roseolovirus , Adulto , ADN Viral , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Herpesvirus Humano 6/genética , Humanos , Modelos de Riesgos Proporcionales , Linfocitos T , Trasplante Homólogo/efectos adversos
8.
Clin Infect Dis ; 75(5): 795-804, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34979021

RESUMEN

BACKGROUND: Cytomegalovirus (CMV)-seropositive (R+) hematopoietic cell transplant (HCT) recipients have a survival disparity compared with CMV-seronegative recipient/donor (R-D-) pairs. We hypothesized that primary letermovir prophylaxis (LET) may abrogate this disparity. We investigated the relationship between LET and mortality at 1 year post-HCT. METHODS: In this retrospective cohort study, we included adult R-D- or R+ patients who received HCT pre-LET (between 1 January 2013 through 15 December 2017) and post-LET (between 16 December 2017 through December 2019). R+ were categorized by LET receipt as R+/LET or R+/no-LET. Cox proportional hazard models were used to estimate the association of LET with all-cause mortality at 1 year after transplantation. RESULTS: Of 848 patients analyzed, 305 were R-D-, 364 R+/no-LET, and 160 R+/LET. Because of similar mortality (adjusted hazard ratio [aHR], 1.29 [95% confidence interval {CI}, .76-2.18]; P = .353]) between pre-LET/R-D- and post-LET/R-D-, R-D- were combined into 1 group. Compared with R-D-, the aHR for mortality was 1.40 (95% CI, 1.01-1.93) for R+/no-LET and 0.89 (95% CI, .57-1.41) for R+/LET. Among R+, LET was associated with decreased risk of death (aHR, 0.62 [95% CI, .40-.98]); when conventional HCT and T-cell depleted HCT were analyzed separately, the aHR was 0.86 (95% CI, .51-1.43) and 0.21 (95% CI, .07-.65), respectively. CONCLUSIONS: At 1 year post-HCT, LET was associated with closing the mortality disparity between R-D- and R+. Among all R+, LET was associated with decreased mortality, driven by 79% reduced incidence of death in T-cell depleted HCT.


Asunto(s)
Infecciones por Citomegalovirus , Trasplante de Células Madre Hematopoyéticas , Acetatos , Adulto , Antivirales/uso terapéutico , Citomegalovirus , Infecciones por Citomegalovirus/epidemiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Quinazolinas , Estudios Retrospectivos
9.
Blood ; 136(1): 130-136, 2020 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-32430495

RESUMEN

Studies of the relationship between the gastrointestinal microbiota and outcomes in allogeneic hematopoietic stem cell transplantation (allo-HCT) have thus far largely focused on early complications, predominantly infection and acute graft-versus-host disease (GVHD). We examined the potential relationship of the microbiome with chronic GVHD (cGVHD) by analyzing stool and plasma samples collected late after allo-HCT using a case-control study design. We found lower circulating concentrations of the microbe-derived short-chain fatty acids (SCFAs) propionate and butyrate in day 100 plasma samples from patients who developed cGVHD, compared with those who remained free of this complication, in the initial case-control cohort of transplant patients and in a further cross-sectional cohort from an independent transplant center. An additional cross-sectional patient cohort from a third transplant center was analyzed; however, serum (rather than plasma) was available, and the differences in SCFAs observed in the plasma samples were not recapitulated. In sum, our findings from the primary case-control cohort and 1 of 2 cross-sectional cohorts explored suggest that the gastrointestinal microbiome may exert immunomodulatory effects in allo-HCT patients at least in part due to control of systemic concentrations of microbe-derived SCFAs.


Asunto(s)
Butiratos/sangre , Microbioma Gastrointestinal , Enfermedad Injerto contra Huésped/microbiología , Propionatos/sangre , Adulto , Aloinjertos , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Estudios de Casos y Controles , Enfermedad Crónica , Disbiosis/etiología , Disbiosis/microbiología , Heces/microbiología , Enfermedad Injerto contra Huésped/sangre , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Metaboloma , Ribotipificación
10.
Artículo en Inglés | MEDLINE | ID: mdl-35586753

RESUMEN

Identification of pathogens with pulmonary presentation in patients with hematologic malignancies may be challenging due to diagnostic difficulty related to the underlying malignancy and limitations of conventional microbiologic methods. Herein, we present a case series of three patients with pulmonary consolidations due to Legionella bozemanae necrotizing pneumonia, Pneumocystis jirovecii pneumonia, and disseminated Scedosporium infection, who were diagnosed by microbial cell-free DNA next-generation sequencing. We observed that this new sequencing modality was in agreement with gold-standard diagnostics, posing a potential solution to the problem of limited capability in diagnosing infections in hematological malignancy patients.

11.
J Infect Dis ; 224(4): 620-631, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-33864371

RESUMEN

BACKGROUND: We investigatedthe association between time-averaged area under the curve (AAUC) of cytomegalovirus (CMV) viral load (VL) by day 100 and overall survival (OS) at 1-year after hematopoietic cell transplantation (HCT). METHODS: In a retrospective cohort study, including patients receiving HCT between June 2010 and December 2017 from Memorial Sloan Kettering Cancer Center, AAUC was calculated for patients with detected VL. Patients were categorized into non-controllers (Q4) and controllers (Q1-Q3) using the highest AAUC quartile as cutoff. Cox models were used to estimate the association between AAUC and OS. Patients with non-detected CMV VL were categorized into elite-controllers (recipient+ [R+] or R-/donor+ [D+]) and R-/D-. RESULTS: The study (N = 952) included 282 controllers, 93 non-controllers, 275 elite-controllers, and 302 R-/D-. OS was 80.1% and 58.1% for controllers and non-controllers, respectively. In multivariable models, non-controllers had worse OS versus controllers (adjusted hazard ratio [HR] = 2.65; 95% confidence interval [CI], 1.71-4.12). In landmark analyses, controllers had similar OS as elite-controllers (HR = 1.26; 95% CI, .83-1.91) or R-/D- (HR = 0.98; 95% CI, .64-1.5). CONCLUSIONS: Non-controllers had worse OS 1-year post-HCT. Controllers had similar OS as elite-controllers or R-/D-. Future studies are needed to validate our AAUC cutoff across different cohorts and CMV management strategies.


Asunto(s)
Infecciones por Citomegalovirus , Trasplante de Células Madre Hematopoyéticas , Insuficiencia Multiorgánica/mortalidad , Carga Viral , Citomegalovirus , Infecciones por Citomegalovirus/mortalidad , Humanos , Cinética , Insuficiencia Multiorgánica/virología , Estudios Retrospectivos , Tasa de Supervivencia
12.
J Neurosci ; 40(48): 9260-9271, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33097638

RESUMEN

Memory stability is essential for animal survival when environment and behavioral state change over short or long time spans. The stability of a memory can be expressed by its duration, its perseverance when conditions change as well as its specificity to the learned stimulus. Using optogenetic and pharmacological manipulations in male mice, we show that the presence of noradrenaline in the olfactory bulb during acquisition renders olfactory memories more stable. We show that while inhibition of noradrenaline transmission during an odor-reward acquisition has no acute effects, it alters perseverance, duration, and specificity of the memory. We use a computational approach to propose a proof of concept model showing that a single, simple network effect of noradrenaline on olfactory bulb dynamics can underlie these seemingly different behavioral effects. Our results show that acute changes in network dynamics can have long-term effects that extend beyond the network that was manipulated.SIGNIFICANCE STATEMENT Olfaction guides the behavior of animals. For successful survival, animals have to remember previously learned information and at the same time be able to acquire new memories. We show here that noradrenaline in the olfactory bulb, the first cortical relay of the olfactory information, is important for creating stable and specific olfactory memories. Memory stability, as expressed in perseverance, duration and specificity of the memory, is enhanced when noradrenergic inputs to the olfactory bulb are unaltered. We show that, computationally, our diverse behavioral results can be ascribed to noradrenaline-driven changes in neural dynamics. These results shed light on how very temporary changes in neuromodulation can have a variety of long-lasting effects on neural processing and behavior.


Asunto(s)
Memoria/fisiología , Norepinefrina/fisiología , Bulbo Olfatorio/fisiología , Olfato/fisiología , Animales , Simulación por Computador , Masculino , Memoria a Largo Plazo/fisiología , Ratones , Ratones Endogámicos C57BL , Neuronas/fisiología , Norepinefrina/metabolismo , Odorantes , Bulbo Olfatorio/metabolismo , Vías Olfatorias/fisiología , Aprendizaje Inverso/fisiología , Recompensa , Sinapsis/fisiología , Transmisión Sináptica
13.
Annu Rev Med ; 70: 381-393, 2019 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-30359171

RESUMEN

Allogeneic hematopoietic cell transplantation is a fundamental part of the treatment of hematologic malignancies and marrow failure syndromes, but complications including graft-versus-host disease, prolonged immune deficiency and infection, and organ toxicities, as well as relapse, remain obstacles to improved overall survival. As the cellular characteristics of the allograft can exert significant impact on outcomes, the development of more strategically designed grafts represents a rich area for therapeutic intervention. We describe the use of ex vivo T cell-depleted grafts as a model for the targeted graft and review evolving knowledge and approaches for further refinement of allografts to improve patient outcomes.


Asunto(s)
Enfermedad Injerto contra Huésped/etiología , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/métodos , Depleción Linfocítica/métodos , Femenino , Rechazo de Injerto , Supervivencia de Injerto , Enfermedad Injerto contra Huésped/fisiopatología , Neoplasias Hematológicas/mortalidad , Neoplasias Hematológicas/patología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Masculino , Pronóstico , Recurrencia , Medición de Riesgo , Análisis de Supervivencia , Trasplante Homólogo , Resultado del Tratamiento
14.
Learn Mem ; 27(10): 414-417, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32934093

RESUMEN

We present evidence that experience and cholinergic modulation in an early sensory network interact to improve certainty about olfactory stimuli. The data we present are in agreement with existing theoretical ideas about the functional role of acetylcholine but highlight the importance of early sensory networks in addition to cortical networks. We use a simple behavioral paradigm in mice which allows us to measure certainty about a stimulus via the response amplitude to a condition and novel stimuli. We conclude that additional learning increases certainty and that the slope of this relationship can be modulated by activation of muscarinic cholinergic receptors in the olfactory bulb.


Asunto(s)
Bulbo Olfatorio/fisiología , Receptores Muscarínicos/fisiología , Olfato/fisiología , Acetilcolina/metabolismo , Animales , Condicionamiento Clásico , Aprendizaje/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Vías Nerviosas/fisiología , Odorantes
15.
Eur J Nucl Med Mol Imaging ; 47(8): 1961-1970, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31863138

RESUMEN

PURPOSE: Imaging studies of cobalt toxicity from cobalt-chromium alloy arthroprosthetics have focused on the local intra-articular and peri-articular presentation from failing joint replacements. Most studies investigating neurological findings have been small case series focused on the clinical findings of memory loss, diminished executive function, tremor, hearing and vision loss, depression, and emotional lability. This study utilizes software-based quantitative analysis of brain metabolism to assess the degree of hypometabolism and areas of susceptibility, determine if a pattern of involvement exists, and measure reversibility of findings after prosthetic revision to cobalt-free appliances. METHODS: Over 48 months, 247 consecutive patients presenting to an orthopedic clinic with an arthroprosthetic joint containing any cobalt-chromium part were screened with whole blood and urine cobalt levels. A clinically validated inventory of 10 symptoms was obtained. Symptomatic patients with a blood cobalt level above 0.4 mcg/L or urine cobalt greater than 1 mcg/L underwent F-18 FDG PET brain imaging. Analysis was performed with FDA-approved quantitative brain analysis software with the pons as the reference region. Control group was the normal brain atlas within the software. RESULTS: Of the 247 consecutively screened patients, 123 had blood and urine cobalt levels above the threshold. The 69 scanned patients had statistically significant regional hypometabolism and higher symptoms inventory. Fifty-seven patients were retained in the study. Distribution of hypometabolism was in descending order: temporal, frontal, Broca's areas, anterior cingulate, parietal, posterior cingulate, visual, sensorimotor, thalamic, and lastly caudate. Metal-on-metal (MoM) and metal-on-plastic (MoP) joint replacements produced similar patterns of hypometabolism. Of 15 patients with necessary revision surgery, 8 demonstrated improved metabolism when later re-scanned. CONCLUSION: All scanned patients had regions of significant hypometabolism. Neurological toxicity from elevated systemic cobalt levels following arthroprosthetic joint replacement has a pattern of regional susceptibility similar to heavy metals and solvents, differing from classical dementias and may occur at blood and urine cobalt levels as low as 0.4 mcg/L and 1 mcg/L, respectively. Presently accepted thresholds for cobalt exposure and monitoring may need revision. Quantitative F-18 FDG PET brain imaging may aid in the decision process for treatment options and timing of possible medical versus surgical intervention.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Encéfalo , Fluorodesoxiglucosa F18 , Humanos , Neuroimagen
16.
Biol Blood Marrow Transplant ; 25(8): 1526-1535, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30831208

RESUMEN

Antithymocyte globulin (ATG) use mitigates the risk of graft rejection and graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (allo-HCT), but ATG overexposure in the setting of lymphopenia negatively affects immune recovery. We hypothesized that standard empiric weight-based dosing of ATG, used to prevent graft rejection in ex vivo CD34-selected allo-HCT, may lead to serious adverse consequences on outcomes in certain patients. We evaluated 304 patients undergoing myeloablative-conditioned ex vivo CD34-selected allo-HCT with HLA-matched donors for the treatment of hematologic malignancies. Patients received rabbit ATG at a dose of 2.5 mg/kg/day i.v. on days -3 and/or -2. An ATG dosing cutoff of 450 mg was used for statistical analyses to assess the relationship between ATG and overall survival (OS). Among all patients, median total ATG dose was 360 mg (range, 130 to 510 mg); 279 (92%) received a total dose of ATG ≤450 mg, and 25 (8%) received a total dose >450 mg. On the first day of ATG administration (day -3), the median absolute lymphocyte count was .0 K/µL. For patients who received a total dose of ATG >450 mg or ≤450 mg, the incidences of acute and late-acute GVHD grade II-IV were statistically similar. At 3 years post-HCT, for patients who received a total dose of ATG >450 mg or ≤450 mg, nonrelapse mortality (NRM) rates were 35% and 18%, respectively (P = .029), disease-free survival (DFS) rates were 37% and 61%, respectively (P = .003), and OS rates were 40% and 67%, respectively (P = .001). Among all patient and HCT characteristics in multivariable analyses, receipt of a total dose of ATG >450 mg was associated with an increased risk of NRM (hazard ratio [HR], 2.9; P = .01), shorter DFS (HR, 2.0; P = .03), and inferior OS (HR, 2.1; P = .01). In summary, the use of weight-based ATG at a time of relative lymphopenia before ex vivo CD34-selected allo-HCT results in overdosing in heavier patients, leading to higher NRM and lower DFS and OS. Further pharmacokinetic investigation in this setting is critical to determining the optimal dosing strategy for ATG.


Asunto(s)
Suero Antilinfocítico/efectos adversos , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Linfopenia , Acondicionamiento Pretrasplante/efectos adversos , Adulto , Anciano , Aloinjertos , Antígenos CD34 , Suero Antilinfocítico/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Neoplasias Hematológicas/sangre , Neoplasias Hematológicas/mortalidad , Neoplasias Hematológicas/terapia , Humanos , Linfopenia/sangre , Linfopenia/inducido químicamente , Linfopenia/mortalidad , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia
17.
Biol Blood Marrow Transplant ; 25(6): 1136-1141, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30625387

RESUMEN

Immune-mediated cytopenias (ICs), such as immune thrombocytopenia and immune hemolytic anemia, are among the adverse events after allogeneic hematopoietic cell transplantation (allo-HCT). Previous reports suggest that in vivo T cell depletion may increase the incidence of IC after allo-HCT. We evaluated whether a strategy that reduces functional donor T cells via ex vivo CD34+-selection associates with the development of IC in a cohort of 408 patients who underwent allo-HCT for hematologic malignancy. The cumulative incidence of IC at 6, 12, and 36 months after the 30-day landmark post-HCT was 3.4%, 4.9%, and 5.8%, respectively. Among 23 patients who developed IC, 7 died of relapse-related mortality and 4 of nonrelapse mortality. A median 2 types of treatment (range, 1 to 5) was required to resolve IC, and there was considerable heterogeneity in the therapies used. In univariable analyses, a hematologic malignancy Disease Risk Index (DRI) score of 3 was significantly associated with an increased risk of IC compared with a DRI of 1 or 2 (hazard ratio [HR], 4.12; P = .003), and IC (HR, 2.4; P = .03) was associated with increased risk of relapse. In a multivariable analysis that included DRI, IC remained significantly associated with increased risk of relapse (HR, 2.4; P = .03). Our findings show that IC events occur with relatively similar frequency in patients after ex vivo CD34+-selected allo-HCT compared with unmodified allo-HCT, suggesting that reduced donor T cell immunity is not causative of IC. Moreover, we noted a possible link between its development and/or treatment and increased risk of relapse.


Asunto(s)
Recuento de Células Sanguíneas/métodos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Acondicionamiento Pretrasplante/efectos adversos , Trasplante Homólogo/efectos adversos , Adulto , Anciano , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo/métodos , Adulto Joven
19.
Am J Orthod Dentofacial Orthop ; 155(3): 432-442, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30826046

RESUMEN

INTRODUCTION: Orthodontics is evolving with advances in 3D imaging, additive fabrication, digital scanning, and treatment planning. With digital tools, orthodontic treatment may become more predictable, efficient, and effective while reducing side-effects. These technologies are affecting patient care, but knowledge of their adoption patterns and influence is incomplete. We aimed to identify adoption decision makers, information sources, perspectives, incentives, and barriers. METHODS: Twenty-four privately practicing orthodontists were interviewed in a semistructured format following a topic guide. Interview transcripts were analyzed to identify factors in technology adoption and its perceived influence on practice. Thematic patterns were established through iterative systematic analysis, and qualitative validity was ensured with researcher triangulation. RESULTS: Qualitative interviews revealed that orthodontists make purchasing decisions independently from staff, after consulting other dentists and company representatives. Meetings, residency training, and continuing education courses are influential information sources, whereas research literature is not. Early and middle adopters are integrating digital imaging, planning, and fabrication technologies into practice and view enhanced ease of use, capabilities, performance, and procedural efficiency as primary incentives to adoption. Improving outcomes and patient comfort are not frequently cited as incentives, and all interviewees view cost as the largest barrier. Orthodontists positively perceive the influence of technology on their practices, but are concerned that further innovation and direct-to-consumer products will cause loss of market share. CONCLUSIONS: CAD/CAM appliances, 3D imaging, and digital treatment planning are viewed as future standards of care and are increasingly being incorporated into the orthodontic office. Understanding the technology adoption process can guide innovation to improve treatment and ease the transition into a digital workflow.


Asunto(s)
Actitud del Personal de Salud , Toma de Decisiones , Ortodoncistas/psicología , Tecnología Odontológica/economía , Adulto , Anciano , Femenino , Humanos , Entrevistas como Asunto , Masculino , Massachusetts , Persona de Mediana Edad , North Carolina , Práctica Privada , Investigación Cualitativa
20.
Biol Blood Marrow Transplant ; 24(12): 2517-2522, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30055353

RESUMEN

In a recently published and validated definition of fluid overload (FO), grade ≥ 2 FO was significantly associated with an increased risk of nonrelapse mortality (NRM) after unmodified and haploidentical allogeneic hematopoietic cell transplantation (allo-HCT) using calcineurin inhibitor (CNI)-based graft-versus-host disease (GVHD) prophylaxis. We evaluated the effect of FO on outcomes in 169 patients undergoing myeloablative-conditioned ex vivo CD34+ selected allo-HCT using the same grading scale. Thirty patients (17.8%) had grade ≥ 2 FO within the 30 days after ex vivo CD34+ selected allo-HCT with a median onset at day 11 (range, -8 to 28). Age ≥ 55 years (odds ratio, 3.43; P = .005) and chemotherapy-based conditioning (odds ratio, 3.89; P = .007) were associated with an increased risk of grade ≥ 2 FO. Patients with early grade ≥ 2 FO had a significantly higher NRM when compared with patients with grade < 2 FO (24.1% versus 3.6% at day 100, P = .01). The HCT-specific comorbidity index (HCT-CI) ≥ 3, FEV1 < 80, adjusted DLco < 80, and HLA mismatch were associated with an increased risk of NRM, whereas total body irradiation-based conditioning was associated with a reduced risk of NRM. In a multivariate analysis grade ≥ 2 FO was associated with increased NRM after adjusting for HCT-CI and HLA match (hazard ratio, 2.3; P = .014). There was a trend toward inferior relapse-free survival in patients with grade ≥ 2 FO compared with patients with grade < 2 FO, 62% versus 72% at 1 year (P = .07), and a trend toward inferior overall survival, 69% versus 79% at 1 year (P = 0.06), respectively. Our findings show that FO should be routinely assessed to identify patients at risk for NRM. Despite a CNI-free allo-HCT platform, regimen-related tissue and endothelial injury leads to FO in susceptible patients. FO is a highly relevant post-HCT toxicity that requires further inquiry.


Asunto(s)
Fluidoterapia/efectos adversos , Trasplante de Células Madre Hematopoyéticas/métodos , Trasplante Homólogo/métodos , Adulto , Anciano , Líquidos Corporales , Femenino , Fluidoterapia/mortalidad , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Trasplante Homólogo/mortalidad , Adulto Joven
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