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1.
Cell ; 150(2): 264-78, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22817890

RESUMEN

Most mutations in cancer genomes are thought to be acquired after the initiating event, which may cause genomic instability and drive clonal evolution. However, for acute myeloid leukemia (AML), normal karyotypes are common, and genomic instability is unusual. To better understand clonal evolution in AML, we sequenced the genomes of M3-AML samples with a known initiating event (PML-RARA) versus the genomes of normal karyotype M1-AML samples and the exomes of hematopoietic stem/progenitor cells (HSPCs) from healthy people. Collectively, the data suggest that most of the mutations found in AML genomes are actually random events that occurred in HSPCs before they acquired the initiating mutation; the mutational history of that cell is "captured" as the clone expands. In many cases, only one or two additional, cooperating mutations are needed to generate the malignant founding clone. Cells from the founding clone can acquire additional cooperating mutations, yielding subclones that can contribute to disease progression and/or relapse.


Asunto(s)
Evolución Clonal , Leucemia Mieloide Aguda/genética , Mutación , Adulto , Anciano , Análisis Mutacional de ADN , Progresión de la Enfermedad , Femenino , Estudio de Asociación del Genoma Completo , Células Madre Hematopoyéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/fisiopatología , Masculino , Persona de Mediana Edad , Proteínas de Fusión Oncogénica/genética , Recurrencia , Piel/metabolismo , Adulto Joven
2.
Entropy (Basel) ; 25(12)2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38136464

RESUMEN

We describe boson sampling of interacting atoms from the noncondensed fraction of Bose-Einstein-condensed (BEC) gas confined in a box trap as a new platform for studying computational ♯P-hardness and quantum supremacy of many-body systems. We calculate the characteristic function and statistics of atom numbers via the newly found Hafnian master theorem. Using Bloch-Messiah reduction, we find that interatomic interactions give rise to two equally important entities-eigen-squeeze modes and eigen-energy quasiparticles-whose interplay with sampling atom states determines the behavior of the BEC gas. We infer that two necessary ingredients of ♯P-hardness, squeezing and interference, are self-generated in the gas and, contrary to Gaussian boson sampling in linear interferometers, external sources of squeezed bosons are not required.

3.
Entropy (Basel) ; 24(12)2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36554176

RESUMEN

We propose a multi-qubit Bose-Einstein-condensate (BEC) trap as a platform for studies of quantum statistical phenomena in many-body interacting systems. In particular, it could facilitate testing atomic boson sampling of the excited-state occupations and its quantum advantage over classical computing in a full, controllable and clear way. Contrary to a linear interferometer enabling Gaussian boson sampling of non-interacting non-equilibrium photons, the BEC trap platform pertains to an interacting equilibrium many-body system of atoms. We discuss a basic model and the main features of such a multi-qubit BEC trap.

4.
Clin Infect Dis ; 73(7): e1613-e1620, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-32966574

RESUMEN

BACKGROUND: Recurrent Clostridioides difficile infections (rCDI) are a global public health threat. To reduce rCDI, microbiota-restoring therapies are needed, particularly standardized, easy-to-administer formulations. METHODS: This phase I open-label trial assessed the safety, efficacy in preventing rCDI recurrence, and intestinal microbiome effects of RBX7455, a room temperature-stable, orally administered investigational live biotherapeutic. Adult participants with 1 or more prior episodes of rCDI received: 4 RBX7455 capsules twice daily for 4 days (group 1); 4 RBX7455 capsules twice daily for 2 days (group 2); or 2 RBX7455 capsules twice daily for 2 days (group 3). For all groups, the first dose was administered in clinic, with remaining doses self-administered at home. Adverse events were monitored during and for 6 months after treatment. Treatment success was defined as rCDI prevention through 8 weeks after treatment. Participants' microbiome composition was assessed prior to and for 6 months after treatment. RESULTS: Nine of 10 group 1 patients (90%), 8 of 10 group 2 patients (80%), and 10 of 10 group 3 patients (100%) were recurrence-free at the 8-week endpoint with durability to 6 months. Seventy-five treatment-emergent adverse events were observed in 27 participants with no serious investigational product-related events. Prior to treatment, participants' microbiomes were dissimilar from the RBX7455 composition with decreased Bacteroidia- and Clostridia-class bacteria, whereas after treatment, responders' microbiomes showed increased Bacteroidia and Clostridia. CONCLUSIONS: Three dosing regimens of RBX7455 were safe and effective at preventing rCDI. Responders' microbiomes converged toward the composition of RBX7455. These results support its continued clinical evaluation. CLINICAL TRIALS REGISTRATION: NCT02981316.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium , Microbiota , Adulto , Clostridioides , Infecciones por Clostridium/tratamiento farmacológico , Trasplante de Microbiota Fecal , Humanos , Recurrencia , Resultado del Tratamiento
5.
Mov Disord ; 35(3): 499-503, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31854465

RESUMEN

OBJECTIVE: The objective of this study was to investigate the effects of levodopa on functional brain networks in Parkinson's disease. METHODS: We acquired resting state functional magnetic resonance imaging in 30 drug-naïve participants with Parkinson's disease and 20 age-matched healthy controls. Each participant was studied following administration of a single oral dose of either levodopa or placebo in a randomized, double-blind, crossover design. RESULTS: The greatest observed differences in functional connectivity were between Parkinson's disease versus control participants, independent of pharmacologic intervention. By contrast, the effects of levodopa were much smaller and detectable only in the Parkinson's disease group. Moreover, although levodopa administration in the Parkinson's disease group measurably improved motor performance, it did not increase the similarity of functional connectivity in Parkinson's disease to the control group. CONCLUSIONS: We found that a single, small dose of levodopa did not normalize functional connectivity in drug-naïve Parkinson's disease. © 2019 International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad de Parkinson , Preparaciones Farmacéuticas , Antiparkinsonianos/uso terapéutico , Encéfalo/diagnóstico por imagen , Humanos , Levodopa , Imagen por Resonancia Magnética , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/tratamiento farmacológico
6.
Cereb Cortex ; 29(6): 2509-2523, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29878081

RESUMEN

The hallmark pathology underlying Parkinson disease (PD) is progressive synucleinopathy, beginning in caudal brainstem that later spreads rostrally. However, the primarily subcortical pathology fails to account for the wide spectrum of clinical manifestations in PD. To reconcile these observations, resting-state functional connectivity (FC) can be used to examine dysfunction across distributed brain networks. We measured FC in a large, single-site study of nondemented PD (N = 107; OFF medications) and healthy controls (N = 46) incorporating rigorous quality control measures and comprehensive sampling of cortical, subcortical and cerebellar regions. We employed novel statistical approaches to determine group differences across the entire connectome, at the network-level, and for select brain regions. Group differences respected well-characterized network delineations producing a striking "block-wise" pattern of network-to-network effects. Surprisingly, these results demonstrate that the greatest FC differences involve sensorimotor, thalamic, and cerebellar networks, with notably smaller striatal effects. Split-half replication demonstrates the robustness of these results. Finally, block-wise FC correlations with behavior suggest that FC disruptions may contribute to clinical manifestations in PD. Overall, these results indicate a concerted breakdown of functional network interactions, remote from primary pathophysiology, and suggest that FC deficits in PD are related to emergent network-level phenomena rather than focal pathology.


Asunto(s)
Encéfalo/fisiopatología , Vías Nerviosas/fisiopatología , Enfermedad de Parkinson/fisiopatología , Anciano , Conectoma/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad
7.
Blood ; 129(19): 2680-2692, 2017 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-28292947

RESUMEN

A single subcutaneous (SC) injection of plerixafor results in rapid mobilization of hematopoietic progenitors, but fails to mobilize 33% of normal allogeneic sibling donors in 1 apheresis. We hypothesized that changing the route of administration of plerixafor from SC to IV may overcome the low stem cell yields and allow collection in 1 day. A phase 1 trial followed by a phase 2 efficacy trial was conducted in allogeneic sibling donors. The optimal dose of IV plerixafor was determined to be 0.32 mg/kg. The primary outcome of reducing the failure to collect ≥2 × 106 CD34+/kg recipient weight in 1 apheresis collection to ≤10% was not reached. The failure rate was 34%. Studies evaluating the stem cell phenotype and gene expression revealed a novel plasmacytoid dendritic cell precursor preferentially mobilized by plerixafor with high interferon-α producing ability. The observed cytomegalovirus (CMV) viremia rate for patients at risk was low (15%), as were the rates of acute grade 2-4 graft-versus-host disease (GVHD) (21%). Day 100 treatment related mortality was low (3%). In conclusion, plerixafor results in rapid stem cell mobilization regardless of route of administration and resulted in novel cellular composition of the graft and favorable recipient outcomes. These trials were registered at clinicaltrials.gov as #NCT00241358 and #NCT00914849.


Asunto(s)
Movilización de Célula Madre Hematopoyética/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Compuestos Heterocíclicos/farmacología , Células Madre de Sangre Periférica/efectos de los fármacos , Administración Intravenosa , Adulto , Anciano , Antígenos CD34/análisis , Bencilaminas , Eliminación de Componentes Sanguíneos , Ciclamas , Femenino , Enfermedad Injerto contra Huésped/etiología , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/farmacología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Compuestos Heterocíclicos/administración & dosificación , Compuestos Heterocíclicos/farmacocinética , Humanos , Masculino , Persona de Mediana Edad , Células Madre de Sangre Periférica/citología , Donantes de Tejidos , Transcriptoma/efectos de los fármacos , Trasplante Homólogo/efectos adversos , Trasplante Homólogo/métodos
8.
Stat Med ; 38(29): 5486-5496, 2019 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-31650580

RESUMEN

Many neuroscientists are interested in how connectomes (graphical representations of functional connectivity between areas of the brain) change in relation to covariates. In statistics, changes like this are analyzed using regression, where the outcomes or dependent variables are regressed onto the covariates. However, when the outcome is a complex object, such as connectome graphs, classical regression models cannot be used. The regression approach developed here to work with complex graph outcomes combines recursive partitioning with the Gibbs distribution. We will only discuss the application to connectomes, but the method is generally applicable to any graphical outcome. The method, called Gibbs-RPart, partitions the covariate space into a set of nonoverlapping regions such that the connectomes within regions are more similar than they are to the connectomes in other regions. This paper extends the object-oriented data analysis paradigm for graph-valued data based on the Gibbs distribution, which we have applied previously to hypothesis testing to compare populations of connectomes from distinct groups (see the work of La Rosa et al).


Asunto(s)
Conectoma/estadística & datos numéricos , Bioestadística , Encéfalo/diagnóstico por imagen , Simulación por Computador , Análisis de Datos , Humanos , Funciones de Verosimilitud , Imagen por Resonancia Magnética/estadística & datos numéricos , Modelos Neurológicos , Modelos Estadísticos , Enfermedad de Parkinson/diagnóstico por imagen , Análisis de Regresión
9.
Nature ; 481(7382): 506-10, 2012 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-22237025

RESUMEN

Most patients with acute myeloid leukaemia (AML) die from progressive disease after relapse, which is associated with clonal evolution at the cytogenetic level. To determine the mutational spectrum associated with relapse, we sequenced the primary tumour and relapse genomes from eight AML patients, and validated hundreds of somatic mutations using deep sequencing; this allowed us to define clonality and clonal evolution patterns precisely at relapse. In addition to discovering novel, recurrently mutated genes (for example, WAC, SMC3, DIS3, DDX41 and DAXX) in AML, we also found two major clonal evolution patterns during AML relapse: (1) the founding clone in the primary tumour gained mutations and evolved into the relapse clone, or (2) a subclone of the founding clone survived initial therapy, gained additional mutations and expanded at relapse. In all cases, chemotherapy failed to eradicate the founding clone. The comparison of relapse-specific versus primary tumour mutations in all eight cases revealed an increase in transversions, probably due to DNA damage caused by cytotoxic chemotherapy. These data demonstrate that AML relapse is associated with the addition of new mutations and clonal evolution, which is shaped, in part, by the chemotherapy that the patients receive to establish and maintain remissions.


Asunto(s)
Evolución Clonal/genética , Genoma Humano/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Células Clonales/efectos de los fármacos , Células Clonales/metabolismo , Células Clonales/patología , Daño del ADN/efectos de los fármacos , Análisis Mutacional de ADN , Genes Relacionados con las Neoplasias/genética , Genoma Humano/efectos de los fármacos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Mutagénesis/efectos de los fármacos , Mutagénesis/genética , Recurrencia , Reproducibilidad de los Resultados
10.
Lancet ; 387(10031): 1928-36, 2016 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-26969089

RESUMEN

BACKGROUND: Gut bacteria might predispose to or protect from necrotising enterocolitis, a severe illness linked to prematurity. In this observational prospective study we aimed to assess whether one or more bacterial taxa in the gut differ between infants who subsequently develop necrotising enterocolitis (cases) and those who do not (controls). METHODS: We enrolled very low birthweight (1500 g and lower) infants in the primary cohort (St Louis Children's Hospital) between July 7, 2009, and Sept 16, 2013, and in the secondary cohorts (Kosair Children's Hospital and Children's Hospital at Oklahoma University) between Sept 12, 2011 and May 25, 2013. We prospectively collected and then froze stool samples for all infants. Cases were defined as infants whose clinical courses were consistent with necrotising enterocolitis and whose radiographs fulfilled criteria for Bell's stage 2 or 3 necrotising enterocolitis. Control infants (one to four per case; not fixed ratios) with similar gestational ages, birthweight, and birth dates were selected from the population after cases were identified. Using primers specific for bacterial 16S rRNA genes, we amplified and then pyrosequenced faecal DNA from stool samples. With use of Dirichlet multinomial analysis and mixed models to account for repeated measures, we identified host factors, including development of necrotising enterocolitis, associated with gut bacterial populations. FINDINGS: We studied 2492 stool samples from 122 infants in the primary cohort, of whom 28 developed necrotising enterocolitis; 94 infants were used as controls. The microbial community structure in case stools differed significantly from those in control stools. These differences emerged only after the first month of age. In mixed models, the time-by-necrotising-enterocolitis interaction was positively associated with Gammaproteobacteria (p=0·0010) and negatively associated with strictly anaerobic bacteria, especially Negativicutes (p=0·0019). We studied 1094 stool samples from 44 infants in the secondary cohorts. 18 infants developed necrotising enterocolitis (cases) and 26 were controls. After combining data from all cohorts (166 infants, 3586 stools, 46 cases of necrotising enterocolitis), there were increased proportions of Gammaproteobacteria (p=0·0011) and lower proportions of both Negativicutes (p=0·0013) and the combined Clostridia-Negativicutes class (p=0·0051) in infants who went on to develop necrotising enterocolitis compared with controls. These associations were strongest in both the primary cohort and the overall cohort for infants born at less than 27 weeks' gestation. INTERPRETATION: A relative abundance of Gammaproteobacteria (ie, Gram-negative facultative bacilli) and relative paucity of strict anaerobic bacteria (especially Negativicutes) precede necrotising enterocolitis in very low birthweight infants. These data offer candidate targets for interventions to prevent necrotising enterocolitis, at least among infants born at less than 27 weeks' gestation. FUNDING: National Institutes of Health (NIH), Foundation for the NIH, the Children's Discovery Institute.


Asunto(s)
Disbiosis/microbiología , Enterocolitis Necrotizante/microbiología , Infecciones por Bacterias Gramnegativas , Infecciones por Bacterias Grampositivas , Estudios de Casos y Controles , Heces/microbiología , Femenino , Edad Gestacional , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Humanos , Lactante , Recién Nacido , Recién Nacido de muy Bajo Peso , Masculino , Estudios Prospectivos
11.
Bioinformatics ; 32(13): 2038-40, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27153704

RESUMEN

UNLABELLED: : When designing a case-control study to investigate differences in microbial composition, it is fundamental to assess the sample sizes needed to detect an hypothesized difference with sufficient statistical power. Our application includes power calculation for (i) a recoded version of the two-sample generalized Wald test of the 'HMP' R-package for comparing community composition, and (ii) the Wilcoxon-Mann-Whitney test for comparing operational taxonomic unit-specific abundances between two samples (optional). The simulation-based power calculations make use of the Dirichlet-Multinomial model to describe and generate abundances. The web interface allows for easy specification of sample and effect sizes. As an illustration of our application, we compared the statistical power of the two tests, with and without stratification of samples. We observed that statistical power increases considerably when stratification is employed, meaning that less samples are needed to detect the same effect size with the same power. AVAILABILITY AND IMPLEMENTATION: The web interface is written in R code using Shiny (RStudio Inc., 2016) and it is available at https://fedematt.shinyapps.io/shinyMB The R code for the recoded generalized Wald test can be found at https://github.com/mafed/msWaldHMP CONTACT: Federico.Mattiello@UGent.be.


Asunto(s)
Biología Computacional/métodos , Microbiota , Programas Informáticos , Estudios de Casos y Controles , Humanos , Internet , Modelos Teóricos , Tamaño de la Muestra
12.
Proc Natl Acad Sci U S A ; 111(34): 12522-7, 2014 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-25114261

RESUMEN

In the weeks after birth, the gut acquires a nascent microbiome, and starts its transition to bacterial population equilibrium. This early-in-life microbial population quite likely influences later-in-life host biology. However, we know little about the governance of community development: does the gut serve as a passive incubator where the first organisms randomly encountered gain entry and predominate, or is there an orderly progression of members joining the community of bacteria? We used fine interval enumeration of microbes in stools from multiple subjects to answer this question. We demonstrate via 16S rRNA gene pyrosequencing of 922 specimens from 58 subjects that the gut microbiota of premature infants residing in a tightly controlled microbial environment progresses through a choreographed succession of bacterial classes from Bacilli to Gammaproteobacteria to Clostridia, interrupted by abrupt population changes. As infants approach 33-36 wk postconceptional age (corresponding to the third to the twelfth weeks of life depending on gestational age at birth), the gut is well colonized by anaerobes. Antibiotics, vaginal vs. Caesarian birth, diet, and age of the infants when sampled influence the pace, but not the sequence, of progression. Our results suggest that in infants in a microbiologically constrained ecosphere of a neonatal intensive care unit, gut bacterial communities have an overall nonrandom assembly that is punctuated by microbial population abruptions. The possibility that the pace of this assembly depends more on host biology (chiefly gestational age at birth) than identifiable exogenous factors warrants further consideration.


Asunto(s)
Tracto Gastrointestinal/microbiología , Recien Nacido Prematuro , Microbiota , Factores de Edad , Clostridium/genética , Clostridium/aislamiento & purificación , Estudios de Cohortes , Heces/microbiología , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Microbiota/genética , Estudios Prospectivos , ARN Bacteriano/genética , ARN Ribosómico 16S/genética
13.
Antimicrob Agents Chemother ; 60(12): 7303-7312, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27671074

RESUMEN

Topical antimicrobials are often employed for decolonization and infection prevention and may alter the endogenous microbiota of the skin. The objective of this study was to compare the microbial communities and levels of richness and diversity in community-dwelling subjects and intensive care unit (ICU) patients before and after the use of topical decolonization protocols. We enrolled 15 adults at risk for Staphylococcus aureus infection. Community subjects (n = 8) underwent a 5-day decolonization protocol (twice daily intranasal mupirocin and daily dilute bleach-water baths), and ICU patients (n = 7) received daily chlorhexidine baths. Swab samples were collected from 5 anatomic sites immediately before and again after decolonization. A variety of culture media and incubation environments were used to recover bacteria and fungi; isolates were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry. Overall, 174 unique organisms were recovered. Unique communities of organisms were recovered from the community-dwelling and hospitalized cohorts. In the community-dwelling cohort, microbial richness and diversity did not differ significantly between collections across time points, although the number of body sites colonized with S. aureus decreased significantly over time (P = 0.004). Within the hospitalized cohort, richness and diversity decreased over time compared to those for the enrollment sampling (from enrollment to final sampling, P = 0.01 for both richness and diversity). Topical antimicrobials reduced the burden of S. aureus while preserving other components of the skin and nasal microbiota.


Asunto(s)
Antibacterianos/uso terapéutico , Antiinfecciosos Locales/uso terapéutico , Clorhexidina/uso terapéutico , Microbiota/efectos de los fármacos , Mupirocina/uso terapéutico , Piel/microbiología , Hipoclorito de Sodio/uso terapéutico , Staphylococcus aureus/aislamiento & purificación , Adulto , Anciano , Infección Hospitalaria/prevención & control , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Nariz/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/prevención & control , Staphylococcus aureus/efectos de los fármacos
14.
Stat Med ; 35(4): 566-80, 2016 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-26608238

RESUMEN

This paper develops object-oriented data analysis (OODA) statistical methods that are novel and complementary to existing methods of analysis of human brain scan connectomes, defined as graphs representing brain anatomical or functional connectivity. OODA is an emerging field where classical statistical approaches (e.g., hypothesis testing, regression, estimation, and confidence intervals) are applied to data objects such as graphs or functions. By analyzing data objects directly we avoid loss of information that occurs when data objects are transformed into numerical summary statistics. By providing statistical tools that analyze sets of connectomes without loss of information, new insights into neurology and medicine may be achieved. In this paper we derive the formula for statistical model fitting, regression, and mixture models; test their performance in simulation experiments; and apply them to connectomes from fMRI brain scans collected during a serial reaction time task study. Software for fitting graphical object-oriented data analysis is provided.


Asunto(s)
Encéfalo/fisiología , Interpretación Estadística de Datos , Imagen por Resonancia Magnética , Adulto , Algoritmos , Encéfalo/anatomía & histología , Distribución de Chi-Cuadrado , Simulación por Computador , Femenino , Humanos , Funciones de Verosimilitud , Masculino , Persona de Mediana Edad , Método de Montecarlo , Tiempo de Reacción , Programas Informáticos
15.
Pediatr Blood Cancer ; 63(12): 2123-2130, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27572136

RESUMEN

BACKGROUND: Vaso-occlusive episodes (VOEs) are a significant source of morbidity among children and adults with sickle cell disease (SCD). There is little information on methadone use for SCD pain. This investigation evaluated methadone pharmacokinetics in children and adults with SCD, with a secondary aim to assess pain relief and opioid consumption. PROCEDURE: Participants included children (<18 years) and adults with a VOE requiring hospitalization. Patients were randomly assigned to receive standard care (opioid patient-controlled analgesia; control group) or one dose of intravenous methadone (0.1-0.125 mg/kg) in addition to standard care (methadone group). Venous methadone and metabolite concentrations were measured. Pain scores, pain relief scores, and opioid consumption were recorded. RESULTS: Twenty-four children (12 methadone, 12 controls) and 23 adults (11 methadone, 12 controls) were studied. In children, the half-life of R- and S-methadone enantiomers was 34 ± 16 and 24 ± 9 hr, respectively. In adults, R- and S-methadone half-lives were 52 ± 17 and 38 ± 12 hr, respectively. Pain scores were lower (P = 0.002) and pain relief scores were higher (P = 0.0396) in children receiving methadone versus controls. There was no difference in pain scores and pain relief in adults receiving methadone versus controls. There was no difference in opioid consumption between methadone and control groups, in both adults and children. CONCLUSIONS: Intravenous methadone disposition in children and adults with SCD was comparable to that in subjects without SCD from prior studies. Methadone produced more pain relief than standard care in children with SCD. Higher methadone doses may be more effective and should be evaluated in both children and adults with SCD.


Asunto(s)
Analgésicos Opioides/farmacocinética , Anemia de Células Falciformes/tratamiento farmacológico , Metadona/farmacocinética , Dolor/tratamiento farmacológico , Adolescente , Anemia de Células Falciformes/fisiopatología , Niño , Femenino , Humanos , Masculino , Metadona/farmacología
16.
FASEB J ; 28(5): 2047-61, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24500923

RESUMEN

Duchenne muscular dystrophy in boys progresses rapidly to severe impairment of muscle function and death in the second or third decade of life. Current supportive therapy with corticosteroids results in a modest increase in strength as a consequence of a general reduction in inflammation, albeit with potential untoward long-term side effects and ultimate failure of the agent to maintain strength. Here, we demonstrate that alternative approaches that rescue defective autophagy in mdx mice, a model of Duchenne muscular dystrophy, with the use of rapamycin-loaded nanoparticles induce a reproducible increase in both skeletal muscle strength and cardiac contractile performance that is not achievable with conventional oral rapamycin, even in pharmacological doses. This increase in physical performance occurs in both young and adult mice, and, surprisingly, even in aged wild-type mice, which sets the stage for consideration of systemic therapies to facilitate improved cell function by autophagic disposal of toxic byproducts of cell death and regeneration.


Asunto(s)
Autofagia/efectos de los fármacos , Inmunosupresores/administración & dosificación , Miocardio/metabolismo , Nanopartículas/química , Sirolimus/administración & dosificación , Corticoesteroides/uso terapéutico , Animales , Muerte Celular , Creatina Quinasa/metabolismo , Sistemas de Liberación de Medicamentos , Fibrosis/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos mdx , Fuerza Muscular , Distrofia Muscular de Duchenne/tratamiento farmacológico , Distrofia Muscular de Duchenne/patología , Contracción Miocárdica , Regeneración , Distribución Tisular
18.
Behav Sleep Med ; 13(3): 208-16, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24654955

RESUMEN

We examined whether an age-related phase advance was present in 60 patients with depression and insomnia (mean age 41.5 [12.5] years) using diaries and 5 weekdays of actigraphy. Actigraphy was analyzed with functional data analysis. The low point of activity (bathyphase) for each subject was fitted by cosine function with 24-hr cycle time. Linear regression analysis revealed that increasing age was associated with earlier bedtimes (p < 0.001), shorter sleep latencies (p < 0.05), and earlier bathyphase (p < 0.001). These findings are consistent with prior reports of age-dependent phase-advances in sleep behavior in self-reported good sleepers and reinforce the premise that individualized behavioral therapy of older persons with insomnia may require prescription of earlier bedtimes and earlier rise times than would be employed in younger persons with insomnia. Further, we demonstrate that aging of the sleep system, at least as reflected in actigraphy, occurs as early as the third decade.


Asunto(s)
Envejecimiento/fisiología , Ritmo Circadiano/fisiología , Depresión/complicaciones , Depresión/fisiopatología , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Sueño/fisiología , Actigrafía , Adolescente , Adulto , Terapia Conductista , Depresión/psicología , Trastorno Depresivo Mayor/complicaciones , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Mayor/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Autoinforme , Trastornos del Inicio y del Mantenimiento del Sueño/terapia , Factores de Tiempo , Adulto Joven
19.
Nature ; 456(7218): 66-72, 2008 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-18987736

RESUMEN

Acute myeloid leukaemia is a highly malignant haematopoietic tumour that affects about 13,000 adults in the United States each year. The treatment of this disease has changed little in the past two decades, because most of the genetic events that initiate the disease remain undiscovered. Whole-genome sequencing is now possible at a reasonable cost and timeframe to use this approach for the unbiased discovery of tumour-specific somatic mutations that alter the protein-coding genes. Here we present the results obtained from sequencing a typical acute myeloid leukaemia genome, and its matched normal counterpart obtained from the same patient's skin. We discovered ten genes with acquired mutations; two were previously described mutations that are thought to contribute to tumour progression, and eight were new mutations present in virtually all tumour cells at presentation and relapse, the function of which is not yet known. Our study establishes whole-genome sequencing as an unbiased method for discovering cancer-initiating mutations in previously unidentified genes that may respond to targeted therapies.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/genética , Genoma Humano/genética , Leucemia Mieloide Aguda/genética , Estudios de Casos y Controles , Progresión de la Enfermedad , Perfilación de la Expresión Génica , Genómica , Humanos , Mutagénesis Insercional , Mutación , Polimorfismo de Nucleótido Simple , Recurrencia , Análisis de Secuencia de ADN , Eliminación de Secuencia , Piel/metabolismo
20.
Science ; 383(6690): 1484-1492, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38547260

RESUMEN

Cellular purines, particularly adenosine 5'-triphosphate (ATP), fuel many metabolic reactions, but less is known about the direct effects of pyrimidines on cellular metabolism. We found that pyrimidines, but not purines, maintain pyruvate oxidation and the tricarboxylic citric acid (TCA) cycle by regulating pyruvate dehydrogenase (PDH) activity. PDH activity requires sufficient substrates and cofactors, including thiamine pyrophosphate (TPP). Depletion of cellular pyrimidines decreased TPP synthesis, a reaction carried out by TPP kinase 1 (TPK1), which reportedly uses ATP to phosphorylate thiamine (vitamin B1). We found that uridine 5'-triphosphate (UTP) acts as the preferred substrate for TPK1, enabling cellular TPP synthesis, PDH activity, TCA-cycle activity, lipogenesis, and adipocyte differentiation. Thus, UTP is required for vitamin B1 utilization to maintain pyruvate oxidation and lipogenesis.


Asunto(s)
Ciclo del Ácido Cítrico , Lipogénesis , Pirimidinas , Complejo Piruvato Deshidrogenasa , Piruvatos , Adenosina Trifosfato/metabolismo , Pirimidinas/metabolismo , Piruvatos/metabolismo , Tiamina/metabolismo , Tiamina Pirofosfato/metabolismo , Uridina Trifosfato/metabolismo , Oxidación-Reducción , Proteínas Quinasas/metabolismo , Humanos , Células HeLa , Complejo Piruvato Deshidrogenasa/metabolismo
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