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1.
Nature ; 615(7951): 276-279, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36859546

RESUMEN

East African aridification during the past 8 million years is frequently invoked as a driver of large-scale shifts in vegetation1 and the evolution of new animal lineages, including hominins2-4. However, evidence for increasing aridity is debated5 and, crucially, the mechanisms leading to dry conditions are unclear6. Here, numerical model experiments show that valleys punctuating the 6,000-km-long East African Rift System (EARS) are central to the development of dry conditions in East Africa. These valleys, including the Turkana Basin in Kenya, cause East Africa to dry by channelling water vapour towards Central Africa, a process that simultaneously enhances rainfall in the Congo Basin rainforest. Without the valleys, the uplift of the rift system leads to a wetter climate in East Africa and a drier climate in the Congo Basin. Results from climate model experiments demonstrate that the detailed tectonic development of Africa has shaped the rainfall distribution, with profound implications for the evolution of African plant and animal lineages.


Asunto(s)
Evolución Biológica , Clima Desértico , Lluvia , Animales , África Oriental , Congo , Hominidae , Kenia , Plantas , Volatilización , Bosque Lluvioso
2.
Nature ; 608(7922): 275-286, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35948707

RESUMEN

The East Antarctic Ice Sheet contains the vast majority of Earth's glacier ice (about 52 metres sea-level equivalent), but is often viewed as less vulnerable to global warming than the West Antarctic or Greenland ice sheets. However, some regions of the East Antarctic Ice Sheet have lost mass over recent decades, prompting the need to re-evaluate its sensitivity to climate change. Here we review the response of the East Antarctic Ice Sheet to past warm periods, synthesize current observations of change and evaluate future projections. Some marine-based catchments that underwent notable mass loss during past warm periods are losing mass at present but most projections indicate increased accumulation across the East Antarctic Ice Sheet over the twenty-first century, keeping the ice sheet broadly in balance. Beyond 2100, high-emissions scenarios generate increased ice discharge and potentially several metres of sea-level rise within just a few centuries, but substantial mass loss could be averted if the Paris Agreement to limit warming below 2 degrees Celsius is satisfied.


Asunto(s)
Modelos Climáticos , Calentamiento Global , Cubierta de Hielo , Temperatura , Regiones Antárticas , Predicción , Calentamiento Global/historia , Calentamiento Global/prevención & control , Calentamiento Global/estadística & datos numéricos , Historia del Siglo XXI , Elevación del Nivel del Mar/historia , Elevación del Nivel del Mar/estadística & datos numéricos
3.
N Engl J Med ; 388(25): 2338-2348, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37342922

RESUMEN

BACKGROUND: In patients undergoing allogeneic hematopoietic stem-cell transplantation (HSCT), a calcineurin inhibitor plus methotrexate has been a standard prophylaxis against graft-versus-host disease (GVHD). A phase 2 study indicated the potential superiority of a post-transplantation regimen of cyclophosphamide, tacrolimus, and mycophenolate mofetil. METHODS: In a phase 3 trial, we randomly assigned adults with hematologic cancers in a 1:1 ratio to receive cyclophosphamide-tacrolimus-mycophenolate mofetil (experimental prophylaxis) or tacrolimus-methotrexate (standard prophylaxis). The patients underwent HSCT from an HLA-matched related donor or a matched or 7/8 mismatched (i.e., mismatched at only one of the HLA-A, HLA-B, HLA-C, and HLA-DRB1 loci) unrelated donor, after reduced-intensity conditioning. The primary end point was GVHD-free, relapse-free survival at 1 year, assessed in a time-to-event analysis, with events defined as grade III or IV acute GVHD, chronic GVHD warranting systemic immunosuppression, disease relapse or progression, and death from any cause. RESULTS: In a multivariate Cox regression analysis, GVHD-free, relapse-free survival was significantly more common among the 214 patients in the experimental-prophylaxis group than among the 217 patients in the standard-prophylaxis group (hazard ratio for grade III or IV acute GVHD, chronic GVHD, disease relapse or progression, or death, 0.64; 95% confidence interval [CI], 0.49 to 0.83; P = 0.001). At 1 year, the adjusted GVHD-free, relapse-free survival was 52.7% (95% CI, 45.8 to 59.2) with experimental prophylaxis and 34.9% (95% CI, 28.6 to 41.3) with standard prophylaxis. Patients in the experimental-prophylaxis group appeared to have less severe acute or chronic GVHD and a higher incidence of immunosuppression-free survival at 1 year. Overall and disease-free survival, relapse, transplantation-related death, and engraftment did not differ substantially between the groups. CONCLUSIONS: Among patients undergoing allogeneic HLA-matched HSCT with reduced-intensity conditioning, GVHD-free, relapse-free survival at 1 year was significantly more common among those who received cyclophosphamide-tacrolimus-mycophenolate mofetil than among those who received tacrolimus-methotrexate. (Funded by the National Heart, Lung, and Blood Institute and others; BMT CTN 1703 ClinicalTrials.gov number, NCT03959241.).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Síndrome de Bronquiolitis Obliterante , Ciclofosfamida , Enfermedad Injerto contra Huésped , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Adulto , Humanos , Síndrome de Bronquiolitis Obliterante/etiología , Síndrome de Bronquiolitis Obliterante/prevención & control , Ciclofosfamida/administración & dosificación , Enfermedad Injerto contra Huésped/prevención & control , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/métodos , Metotrexato/administración & dosificación , Ácido Micofenólico/administración & dosificación , Recurrencia Local de Neoplasia/tratamiento farmacológico , Tacrolimus/administración & dosificación , Donante no Emparentado , Neoplasias Hematológicas/cirugía , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
4.
Blood ; 143(21): 2145-2151, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38364110

RESUMEN

ABSTRACT: Voxelotor is an inhibitor of sickle hemoglobin polymerization that is used to treat sickle cell disease. Although voxelotor has been shown to improve anemia, the clinical benefit on the brain remains to be determined. This study quantified the cerebral hemodynamic effects of voxelotor in children with sickle cell anemia (SCA) using noninvasive diffuse optical spectroscopies. Specifically, frequency-domain near-infrared spectroscopy combined with diffuse correlation spectroscopy were used to noninvasively assess regional oxygen extraction fraction (OEF), cerebral blood volume, and an index of cerebral blood flow (CBFi). Estimates of CBFi were first validated against arterial spin-labeled magnetic resonance imaging (ASL-MRI) in 8 children with SCA aged 8 to 18 years. CBFi was significantly positively correlated with ASL-MRI-measured blood flow (R2 = 0.651; P = .015). Next, a single-center, open-label pilot study was completed in 8 children with SCA aged 4 to 17 years on voxelotor, monitored before treatment initiation and at 4, 8, and 12 weeks (NCT05018728). By 4 weeks, both OEF and CBFi significantly decreased, and these decreases persisted to 12 weeks (both P < .05). Decreases in CBFi were significantly correlated with increases in blood hemoglobin (Hb) concentration (P = .025), whereas the correlation between decreases in OEF and increases in Hb trended toward significance (P = .12). Given that previous work has shown that oxygen extraction and blood flow are elevated in pediatric SCA compared with controls, these results suggest that voxelotor may reduce cerebral hemodynamic impairments. This trial was registered at www.ClinicalTrials.gov as #NCT05018728.


Asunto(s)
Anemia de Células Falciformes , Circulación Cerebrovascular , Oxígeno , Humanos , Anemia de Células Falciformes/sangre , Niño , Adolescente , Masculino , Femenino , Oxígeno/sangre , Oxígeno/metabolismo , Preescolar , Imagen por Resonancia Magnética/métodos , Pirazinas/uso terapéutico , Pirazinas/administración & dosificación , Proyectos Piloto , Benzaldehídos/uso terapéutico , Benzaldehídos/farmacología , Benzaldehídos/administración & dosificación , Espectroscopía Infrarroja Corta/métodos , Pirazoles
5.
Cell ; 147(4): 853-67, 2011 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-22078882

RESUMEN

Deciphering the signaling networks that underlie normal and disease processes remains a major challenge. Here, we report the discovery of signaling components involved in the Toll-like receptor (TLR) response of immune dendritic cells (DCs), including a previously unkown pathway shared across mammalian antiviral responses. By combining transcriptional profiling, genetic and small-molecule perturbations, and phosphoproteomics, we uncover 35 signaling regulators, including 16 known regulators, involved in TLR signaling. In particular, we find that Polo-like kinases (Plk) 2 and 4 are essential components of antiviral pathways in vitro and in vivo and activate a signaling branch involving a dozen proteins, among which is Tnfaip2, a gene associated with autoimmune diseases but whose role was unknown. Our study illustrates the power of combining systematic measurements and perturbations to elucidate complex signaling circuits and discover potential therapeutic targets.


Asunto(s)
Células Dendríticas/inmunología , Transducción de Señal , Receptores Toll-Like/metabolismo , Virus , Animales , Células Dendríticas/metabolismo , Femenino , Humanos , Factor 3 Regulador del Interferón/metabolismo , Interferones/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo
6.
Blood ; 141(25): 3031-3038, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37084383

RESUMEN

Severe aplastic anemia (SAA) is a marrow failure disorder with high morbidity and mortality. It is treated with bone marrow transplantation (BMT) for those with fully matched donors, or immunosuppressive therapy (IST) for those who lack such a donor, which is often the case for underrepresented minorities. We conducted a prospective phase 2 trial of reduced-intensity conditioning HLA-haploidentical BMT and posttransplantation cyclophosphamide (PTCy)-based graft-versus-host (GVHD) prophylaxis as initial therapy for patients with SAA. The median patient age was 25 years (range, 3-63 years), and the median follow-up time was 40.9 months (95% confidence interval [CI], 29.4-55.7). More than 35% of enrollment was from underrepresented racial/ethnic groups. The cumulative incidence of grade 2 or 4 acute GVHD on day 100 was 7% (95% CI, not applicable [NA]-17), and chronic GVHD at 2 years was 4% (95% CI, NA-11). The overall survival of 27 patients was 92% (95% CI, 83-100) at 1, 2, and 3 years. The first 7 patients received lower dose total body irradiation (200 vs 400 cGy), but these patients were more likely to have graft failure (3 of 7) compared with 0 of 20 patients in the higher dose group (P = .01; Fisher exact test). HLA-haploidentical BMT with PTCy using 400 cGy total body irradiation resulted in 100% overall survival with minimal GVHD in 20 consecutive patients. Not only does this approach avoid any adverse ramifications of IST and its low failure-free survival, but the use of haploidentical donors also expands access to BMT across all populations. This trial was registered at www.clinicaltrials.gov as NCT02833805.


Asunto(s)
Anemia Aplásica , Enfermedad Injerto contra Huésped , Humanos , Preescolar , Niño , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Trasplante de Médula Ósea/efectos adversos , Estudios Prospectivos , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/prevención & control , Ciclofosfamida/uso terapéutico
7.
J Med Genet ; 61(11): 1031-1039, 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39237363

RESUMEN

OBJECTIVES: Mutations in the X-linked endosomal Na+/H+ exchanger 6 (NHE6) cause Christianson syndrome (CS). Here, in the largest study to date, we examine genetic diversity and clinical progression in CS into adulthood. METHOD: Data were collected as part of the International Christianson Syndrome and NHE6 (SLC9A6) Gene Network Study. 44 individuals with 31 unique NHE6 mutations, age 2-32 years, were followed prospectively, herein reporting baseline, 1 year follow-up and retrospective natural history. RESULTS: We present data on the CS phenotype with regard to physical growth and adaptive and motor regression across the lifespan including information on mortality. Longitudinal data on body weight and height were examined using a linear mixed model. The rate of growth across development was slow and resulted in prominently decreased age-normed height and weight by adulthood. Adaptive functioning was longitudinally examined; a majority of adult participants (18+ years) lost gross and fine motor skills over a 1 year follow-up. Previously defined core diagnostic criteria for CS (present in>85%)-namely non-verbal status, intellectual disability, epilepsy, postnatal microcephaly, ataxia, hyperkinesia-were universally present in age 6-16; however, an additional core feature of high pain tolerance was added (present in 91%). While neurologic examinations were consistent with cerebellar dysfunction, importantly, a majority of individuals (>50% older than 10) also had corticospinal tract abnormalities. Three participants died during the period of the study. CONCLUSIONS: In this large and longitudinal study of CS, we begin to define the trajectory of symptoms and the adult phenotype thereby identifying critical targets for treatment.


Asunto(s)
Discapacidad Intelectual , Microcefalia , Mutación , Intercambiadores de Sodio-Hidrógeno , Humanos , Adolescente , Adulto , Estudios Longitudinales , Masculino , Niño , Intercambiadores de Sodio-Hidrógeno/genética , Femenino , Adulto Joven , Preescolar , Discapacidad Intelectual/genética , Discapacidad Intelectual/patología , Microcefalia/genética , Microcefalia/patología , Ataxia/genética , Ataxia/patología , Ataxia/fisiopatología , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Fenotipo , Trastornos de la Motilidad Ocular/genética , Trastornos de la Motilidad Ocular/fisiopatología , Hipogonadismo/genética , Hipogonadismo/patología , Epilepsia
8.
J Am Chem Soc ; 146(11): 7763-7770, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38456418

RESUMEN

Blends comprising organic semiconductors and inorganic quantum dots (QDs) are relevant for many optoelectronic applications and devices. However, the individual components in organic-QD blends have a strong tendency to aggregate and phase-separate during film processing, compromising both their structural and electronic properties. Here, we demonstrate a QD surface engineering approach using electronically active, highly soluble semiconductor ligands that are matched to the organic semiconductor host material to achieve well-dispersed inorganic-organic blend films, as characterized by X-ray and neutron scattering, and electron microscopies. This approach preserves the electronic properties of the organic and QD phases and also creates an optimized interface between them. We exemplify this in two emerging applications, singlet-fission-based photon multiplication (SF-PM) and triplet-triplet annihilation-based photon upconversion (TTA-UC). Steady-state and time-resolved optical spectroscopy shows that triplet excitons can be transferred with near unity efficiently across the organic-inorganic interface, while the organic films maintain efficient SF (190% yield) in the organic phase. By changing the relative energy between organic and inorganic components, yellow upconverted emission is observed upon 790 nm NIR excitation. Overall, we provide a highly versatile approach to overcome longstanding challenges in the blending of organic semiconductors with QDs that have relevance for many optical and optoelectronic applications.

9.
Br J Haematol ; 205(4): 1469-1476, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39099174

RESUMEN

BACKGROUND: High-dose post-transplant cyclophosphamide allows safe and effective use of allografts from haploidentical relatives (siblings, parents and children) in patients undergoing allogeneic blood or marrow transplant (alloBMT). More recently, second- and third-degree relatives have also been shown to be safe allograft donors. An increasing number of older patients undergoing alloBMT have been receiving allografts from haploidentical donors. However, older patients are more likely to have older siblings and children, and older donor age is associated with worse outcomes. OBJECTIVE: In the current study, we report the safety and utility of grandchildren as haploidentical donors and compared with children as donors in patients undergoing alloBMT. METHODS: We compared characteristics and outcomes of alloBMT patients aged 55 years and older with children older than 30 years as donors (C group; n = 276) and those with grandchildren as donors (GC group; n = 40). Because many important baseline characteristics predict outcomes after alloBMT, we performed propensity score matched analysis based on recipient age, alloBMT year, disease, graft source and haematopoietic cell transplantation comorbidity index (HCT-CI). RESULTS: The median age of recipients was 67 years (range 55-79) in the C group and 73 years (range 57-78) in the GC group. More than 70% of recipients in the GC group were older than 70 years, compared with 27% in the C group. The median donor age was 37 years (range 31-52) in the C group and 20 years (range 14-34) in the GC group. More patients in the GC group had HCT-CI scores ≥3 than in the C group (32.5% vs. 23%, p = 0.27). Two-year overall survival did not differ between the two groups (GC 62% vs. C 60%, hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.53-1.75, p = 0.90) despite recipients of allografts from grandchildren being older. The 2-year RFS was 55% in the C group compared with 50% in the GC group (HR 1.05, 95% CI 0.62-1.77, p = 0.85). Non-relapse mortality subdistribution [SD] (SDHR 1.36, 95% 0.70-2.63, p = 0.36), relapse (SDHR 0.72, 95% CI 0.33-1.58, p = 0.42) or relapse-free survival (HR 1.05, 95% CI 0.62-1.77, p = 0.85). Propensity score matching analysis showed no significant differences in 2-year overall survival (GC 64% vs. C 53%; HR 0.77, 95% CI 0.42-1.42, p = 0.40), non-relapse mortality (SDHR 1.26, 95% 0.66-2.41, p = 0.48), relapse (SDHR 0.57, 95% CI 0.21-1.52, p = 0.26) or relapse-free survival (HR 0.94, 95% CI 0.57-1.54, p = 0.81). CONCLUSION: Our results indicate that outcomes of alloBMT patients with grandchild donors are similar to those with child donors, despite recipients' older age and higher comorbidities in the GC group. Grandchildren should be considered when selecting a donor for older alloBMT recipients.


Asunto(s)
Trasplante de Médula Ósea , Ciclofosfamida , Enfermedad Injerto contra Huésped , Humanos , Ciclofosfamida/uso terapéutico , Persona de Mediana Edad , Masculino , Femenino , Enfermedad Injerto contra Huésped/prevención & control , Enfermedad Injerto contra Huésped/etiología , Anciano , Trasplante de Médula Ósea/métodos , Trasplante de Médula Ósea/efectos adversos , Adulto , Niño , Adolescente , Trasplante Homólogo , Trasplante Haploidéntico/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Donantes de Tejidos , Adulto Joven , Factores de Edad , Acondicionamiento Pretrasplante/métodos
10.
Hum Brain Mapp ; 45(11): e26781, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39023172

RESUMEN

Attention lapses (ALs) are complete lapses of responsiveness in which performance is briefly but completely disrupted and during which, as opposed to microsleeps, the eyes remain open. Although the phenomenon of ALs has been investigated by behavioural and physiological means, the underlying cause of an AL has largely remained elusive. This study aimed to investigate the underlying physiological substrates of behaviourally identified endogenous ALs during a continuous visuomotor task, primarily to answer the question: Were the ALs during this task due to extreme mind-wandering or mind-blanks? The data from two studies were combined, resulting in data from 40 healthy non-sleep-deprived subjects (20M/20F; mean age 27.1 years, 20-45). Only 17 of the 40 subjects were used in the analysis due to a need for a minimum of two ALs per subject. Subjects performed a random 2-D continuous visuomotor tracking task for 50 and 20 min in Studies 1 and 2, respectively. Tracking performance, eye-video, and functional magnetic resonance imaging (fMRI) were recorded simultaneously. A human expert visually inspected the tracking performance and eye-video recordings to identify and categorise lapses of responsiveness as microsleeps or ALs. Changes in neural activity during 85 ALs (17 subjects) relative to responsive tracking were estimated by whole-brain voxel-wise fMRI and by haemodynamic response (HR) analysis in regions of interest (ROIs) from seven key networks to reveal the neural signature of ALs. Changes in functional connectivity (FC) within and between the key ROIs were also estimated. Networks explored were the default mode network, dorsal attention network, frontoparietal network, sensorimotor network, salience network, visual network, and working memory network. Voxel-wise analysis revealed a significant increase in blood-oxygen-level-dependent activity in the overlapping dorsal anterior cingulate cortex and supplementary motor area region but no significant decreases in activity; the increased activity is considered to represent a recovery-of-responsiveness process following an AL. This increased activity was also seen in the HR of the corresponding ROI. Importantly, HR analysis revealed no trend of increased activity in the posterior cingulate of the default mode network, which has been repeatedly demonstrated to be a strong biomarker of mind-wandering. FC analysis showed decoupling of external attention, which supports the involuntary nature of ALs, in addition to the neural recovery processes. Other findings were a decrease in HR in the frontoparietal network before the onset of ALs, and a decrease in FC between default mode network and working memory network. These findings converge to our conclusion that the ALs observed during our task were involuntary mind-blanks. This is further supported behaviourally by the short duration of the ALs (mean 1.7 s), which is considered too brief to be instances of extreme mind-wandering. This is the first study to demonstrate that at least the majority of complete losses of responsiveness on a continuous visuomotor task are, if not due to microsleeps, due to involuntary mind-blanks.


Asunto(s)
Atención , Imagen por Resonancia Magnética , Desempeño Psicomotor , Humanos , Adulto , Femenino , Masculino , Adulto Joven , Atención/fisiología , Desempeño Psicomotor/fisiología , Persona de Mediana Edad , Tecnología de Seguimiento Ocular , Pensamiento/fisiología , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Red Nerviosa/fisiología , Estado de Conciencia/fisiología , Percepción Visual/fisiología , Actividad Motora/fisiología
11.
Small ; 20(33): e2311109, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38597752

RESUMEN

Controlling the nanomorphology in bulk heterojunction photoactive blends is crucial for optimizing the performance and stability of organic photovoltaic (OPV) technologies. A promising approach is to alter the drying dynamics and consequently, the nanostructure of the blend film using solvent additives such as 1,8-diiodooctane (DIO). Although this approach is demonstrated extensively for OPV systems incorporating fullerene-based acceptors, it is unclear how solvent additive processing influences the morphology and stability of nonfullerene acceptor (NFA) systems. Here, small angle neutron scattering (SANS) is used to probe the nanomorphology of two model OPV systems processed with DIO: a fullerene-based system (PBDB-T:PC71BM) and an NFA-based system (PBDB-T:ITIC). To overcome the low intrinsic neutron scattering length density contrast in polymer:NFA blend films, the synthesis of a deuterated NFA analog (ITIC-d52) is reported. Using SANS, new insights into the nanoscale evolution of fullerene and NFA-based systems are provided by characterizing films immediately after fabrication, after thermal annealing, and after aging for 1 year. It is found that DIO processing influences fullerene and NFA-based systems differently with NFA-based systems characterized by more phase-separated domains. After long-term aging, SANS reveals both systems demonstrate some level of thermodynamic induced domain coarsening.

12.
Crit Care Med ; 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365697

RESUMEN

OBJECTIVES: Neurocritically ill patients are at high risk for developing delirium, which can worsen the long-term outcomes of this vulnerable population. However, existing delirium assessment tools do not account for neurologic deficits that often interfere with conventional testing and are therefore unreliable in neurocritically ill patients. We aimed to determine the accuracy and predictive validity of the Fluctuating Mental Status Evaluation (FMSE), a novel delirium screening tool developed specifically for neurocritically ill patients. DESIGN: Prospective validation study. SETTING: Neurocritical care unit at an academic medical center. PATIENTS: One hundred thirty-nine neurocritically ill stroke patients (mean age, 63.9 [sd, 15.9], median National Institutes of Health Stroke Scale score 11 [interquartile range, 2-17]). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Expert raters performed daily Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition-based delirium assessments, while paired FMSE assessments were performed by trained clinicians. We analyzed 717 total noncomatose days of paired assessments, of which 52% (n = 373) were rated by experts as days with delirium; 53% of subjects were delirious during one or more days. Compared with expert ratings, the overall accuracy of the FMSE was high (area under the curve [AUC], 0.85; 95% CI, 0.82-0.87). FMSE scores greater than or equal to 1 had 86% sensitivity and 74% specificity on a per-assessment basis, while scores greater than or equal to 2 had 70% sensitivity and 88% specificity. Accuracy remained high in patients with aphasia (FMSE ≥ 1: 82% sensitivity, 64% specificity; FMSE ≥ 2: 64% sensitivity, 84% specificity) and those with decreased arousal (FMSE ≥ 1: 87% sensitivity, 77% specificity; FMSE ≥ 2: 71% sensitivity, 90% specificity). Positive FMSE assessments also had excellent accuracy when predicting functional outcomes at discharge (AUC, 0.86 [95% CI, 0.79-0.93]) and 3 months (AUC, 0.85 [95% CI, 0.78-0.92]). CONCLUSIONS: In this validation study, we found that the FMSE was an accurate delirium screening tool in neurocritically ill stroke patients. FMSE scores greater than or equal to 1 indicate "possible" delirium and should be used when prioritizing sensitivity, whereas scores greater than or equal to 2 indicate "probable" delirium and should be used when prioritizing specificity.

13.
Blood ; 139(4): 608-623, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-34657151

RESUMEN

The key immunologic signatures associated with clinical outcomes after posttransplant cyclophosphamide (PTCy)-based HLA-haploidentical (haplo) and HLA-matched bone marrow transplantation (BMT) are largely unknown. To address this gap in knowledge, we used machine learning to decipher clinically relevant signatures from immunophenotypic, proteomic, and clinical data and then examined transcriptome changes in the lymphocyte subsets that predicted major posttransplant outcomes. Kinetics of immune subset reconstitution after day 28 were similar for 70 patients undergoing haplo and 75 patients undergoing HLA-matched BMT. Machine learning based on 35 candidate factors (10 clinical, 18 cellular, and 7 proteomic) revealed that combined elevations in effector CD4+ conventional T cells (Tconv) and CXCL9 at day 28 predicted acute graft-versus-host disease (aGVHD). Furthermore, higher NK cell counts predicted improved overall survival (OS) due to a reduction in both nonrelapse mortality and relapse. Transcriptional and flow-cytometric analyses of recovering lymphocytes in patients with aGVHD identified preserved hallmarks of functional CD4+ regulatory T cells (Tregs) while highlighting a Tconv-driven inflammatory and metabolic axis distinct from that seen with conventional GVHD prophylaxis. Patients developing early relapse displayed a loss of inflammatory gene signatures in NK cells and a transcriptional exhaustion phenotype in CD8+ T cells. Using a multimodality approach, we highlight the utility of systems biology in BMT biomarker discovery and offer a novel understanding of how PTCy influences alloimmune responses. Our work charts future directions for novel therapeutic interventions after these increasingly used GVHD prophylaxis platforms. Specimens collected on NCT0079656226 and NCT0080927627 https://clinicaltrials.gov/.


Asunto(s)
Trasplante de Médula Ósea , Ciclofosfamida/uso terapéutico , Enfermedad Injerto contra Huésped/diagnóstico , Inmunosupresores/uso terapéutico , Adulto , Trasplante de Médula Ósea/efectos adversos , Femenino , Enfermedad Injerto contra Huésped/genética , Enfermedad Injerto contra Huésped/inmunología , Humanos , Reconstitución Inmune , Inmunofenotipificación , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/metabolismo , Aprendizaje Automático , Masculino , Persona de Mediana Edad , Proteómica , Transcriptoma , Adulto Joven
14.
J Int Neuropsychol Soc ; 30(1): 47-55, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37448351

RESUMEN

OBJECTIVE: The Harmonized Cognitive Assessment Protocol (HCAP) describes an assessment battery and a family of population-representative studies measuring neuropsychological performance. We describe the factorial structure of the HCAP battery in the US Health and Retirement Study (HRS). METHOD: The HCAP battery was compiled from existing measures by a cross-disciplinary and international panel of researchers. The HCAP battery was used in the 2016 wave of the HRS. We used factor analysis methods to assess and refine a theoretically driven single and multiple domain factor structure for tests included in the HCAP battery among 3,347 participants with evaluable performance data. RESULTS: For the eight domains of cognitive functioning identified (orientation, memory [immediate, delayed, and recognition], set shifting, attention/speed, language/fluency, and visuospatial), all single factor models fit reasonably well, although four of these domains had either 2 or 3 indicators where fit must be perfect and is not informative. Multidimensional models suggested the eight-domain model was overly complex. A five-domain model (orientation, memory delayed and recognition, executive functioning, language/fluency, visuospatial) was identified as a reasonable model for summarizing performance in this sample (standardized root mean square residual = 0.05, root mean square error of approximation = 0.05, confirmatory fit index = 0.94). CONCLUSIONS: The HCAP battery conforms adequately to a multidimensional structure of neuropsychological performance. The derived measurement models can be used to operationalize notions of neurocognitive impairment, and as a starting point for prioritizing pre-statistical harmonization and evaluating configural invariance in cross-national research.


Asunto(s)
Disfunción Cognitiva , Jubilación , Humanos , Pruebas Neuropsicológicas , Cognición , Función Ejecutiva , Atención , Disfunción Cognitiva/diagnóstico
15.
J Int Neuropsychol Soc ; : 1-9, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39301587

RESUMEN

OBJECTIVE: The psychometric rigor of unsupervised, smartphone-based assessments and factors that impact remote protocol engagement is critical to evaluate prior to the use of such methods in clinical contexts. We evaluated the validity of a high-frequency, smartphone-based cognitive assessment protocol, including examining convergence and divergence with standard cognitive tests, and investigating factors that may impact adherence and performance (i.e., time of day and anticipated receipt of feedback vs. no feedback). METHODS: Cognitively unimpaired participants (N = 120, Mage = 68.8, 68.3% female, 87% White, Meducation = 16.5 years) completed 8 consecutive days of the Mobile Monitoring of Cognitive Change (M2C2), a mobile app-based testing platform, with brief morning, afternoon, and evening sessions. Tasks included measures of working memory, processing speed, and episodic memory. Traditional neuropsychological assessments included measures from the Preclinical Alzheimer's Cognitive Composite battery. RESULTS: Findings showed overall high compliance (89.3%) across M2C2 sessions. Average compliance by time of day ranged from 90.2% for morning sessions, to 77.9% for afternoon sessions, and 84.4% for evening sessions. There was evidence of faster reaction time and among participants who expected to receive performance feedback. We observed excellent convergent and divergent validity in our comparison of M2C2 tasks and traditional neuropsychological assessments. CONCLUSIONS: This study supports the validity and reliability of self-administered, high-frequency cognitive assessment via smartphones in older adults. Insights into factors affecting adherence, performance, and protocol implementation are discussed.

16.
Int J Geriatr Psychiatry ; 39(1): e6044, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38161287

RESUMEN

OBJECTIVES: Determine if biomarkers of Alzheimer's disease and neural injury may play a role in the prediction of delirium risk. METHODS: In a cohort of older adults who underwent elective surgery, delirium case-no delirium control pairs (N = 70, or 35 matched pairs) were matched by age, sex and vascular comorbidities. Biomarkers from CSF and plasma samples collected prior to surgery, including amyloid beta (Aß)42 , Aß40 , total (t)-Tau, phosphorylated (p)-Tau181 , neurofilament-light (NfL), and glial fibrillary acid protein (GFAP) were measured in cerebrospinal fluid (CSF) and plasma using sandwich enzyme-linked immunosorbent assays (ELISAs) or ultrasensitive single molecule array (Simoa) immunoassays. RESULTS: Plasma GFAP correlated significantly with CSF GFAP and both plasma and CSF GFAP values were nearly two-fold higher in delirium cases. The median paired difference between delirium case and control without delirium for plasma GFAP was not significant (p = 0.074) but higher levels were associated with a greater risk for delirium (odds ratio 1.52, 95% confidence interval 0.85, 2.72 per standard deviation increase in plasma GFAP concentration) in this small study. No matched pair differences or associations with delirium were observed for NfL, p-Tau 181, Aß40 and Aß42 . CONCLUSIONS: These preliminary findings suggest that plasma GFAP, a marker of astroglial activation, may be worth further investigation as a predictive risk marker for delirium.


Asunto(s)
Enfermedad de Alzheimer , Delirio , Humanos , Anciano , Péptidos beta-Amiloides , Proteínas tau , Enfermedad de Alzheimer/líquido cefalorraquídeo , Biomarcadores , Delirio/diagnóstico
17.
Environ Health ; 23(1): 28, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38504322

RESUMEN

BACKGROUND: The effects of organochlorine pesticide (OCP) exposure on the development of human papillary thyroid cancer (PTC) are not well understood. A nested case-control study was conducted with data from the U.S. Department of Defense Serum Repository (DoDSR) cohort between 2000 and 2013 to assess associations of individual OCPs serum concentrations with PTC risk. METHODS: This study included 742 histologically confirmed PTC cases (341 females, 401 males) and 742 individually-matched controls with pre-diagnostic serum samples selected from the DoDSR. Associations between categories of lipid-corrected serum concentrations of seven OCPs and PTC risk were evaluated for classical PTC and follicular PTC using conditional logistic regression, adjusted for body mass index category and military branch to compute odds ratios (OR) and 95% confidence intervals (CIs). Effect modification by sex, birth cohort, and race was examined. RESULTS: There was no evidence of associations between most of the OCPs and PTC, overall or stratified by histological subtype. Overall, there was no evidence of an association between hexachlorobenzene (HCB) and PTC, but stratified by histological subtype HCB was associated with significantly increased risk of classical PTC (third tertile above the limit of detection (LOD) vs.

Asunto(s)
Hexaclorociclohexano , Hidrocarburos Clorados , Personal Militar , Plaguicidas , Neoplasias de la Tiroides , Masculino , Humanos , Femenino , Cáncer Papilar Tiroideo/epidemiología , Hexaclorobenceno , Estudios de Casos y Controles , Neoplasias de la Tiroides/inducido químicamente , Neoplasias de la Tiroides/epidemiología
18.
Mol Cell Proteomics ; 21(7): 100250, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35618225

RESUMEN

As a key structural component of the chromatin of higher eukaryotes, linker histones (H1s) are involved in stabilizing the folding of extended nucleosome arrays into higher-order chromatin structures and function as a gene-specific regulator of transcription in vivo. The H1 C-terminal domain (CTD) is essential for high-affinity binding of linker histones to chromatin and stabilization of higher-order chromatin structure. Importantly, the H1 CTD is an intrinsically disordered domain that undergoes a drastic condensation upon binding to nucleosomes. Moreover, although phosphorylation is a prevalent post-translational modification within the H1 CTD, exactly where this modification is installed and how phosphorylation influences the structure of the H1 CTD remains unclear for many H1s. Using novel mass spectrometry techniques, we identified six phosphorylation sites within the CTD of the archetypal linker histone Xenopus H1.0. We then analyzed nucleosome-dependent CTD condensation and H1-dependent linker DNA organization for H1.0 in which the phosphorylated serine residues were replaced by glutamic acid residues (phosphomimics) in six independent mutants. We find that phosphomimetics at residues S117E, S155E, S181E, S188E, and S192E resulted in a significant reduction in nucleosome-bound H1.0 CTD condensation compared with unphosphorylated H1.0, whereas S130E did not alter CTD structure. Furthermore, we found distinct effects among the phosphomimetics on H1-dependent linker DNA trajectory, indicating unique mechanisms by which this modification can influence H1 CTD condensation. These results bring to light a novel role for linker histone phosphorylation in directly altering the structure of nucleosome-bound H1 and a potential novel mechanism for its effects on chromatin structure and function.


Asunto(s)
Histonas , Nucleosomas , Animales , Cromatina , ADN/química , Histonas/metabolismo , Fosforilación , Xenopus laevis/metabolismo
19.
Sleep Breath ; 28(4): 1609-1616, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38717716

RESUMEN

PURPOSE: It is well established that, together with a multitude of other adverse effects on health, severe obstructive sleep apnoea causes reduced cerebral perfusion and, in turn, reduced cerebral function. Less clear is the impact of moderate obstructive sleep apnoea (OSA). Our aim was to determine if cerebral blood flow is impaired in people diagnosed with moderate OSA. METHODS: Twenty-four patients diagnosed with moderate OSA (15 ≤ apnoea-hypopnea index (AHI) < 30) were recruited (aged 32-72, median 59 years, 10 female). Seven controls (aged 42-73 years, median 62 years, 4 female) with an AHI < 5 were also recruited. The OSA status of all participants was confirmed at baseline by unattended polysomnography and they had an MRI arterial-spin-labelling scan of cerebral perfusion. RESULTS: Neither global perfusion nor voxel-wise perfusion differed significantly between the moderate-OSA and control groups. We also compared the average perfusion across three regional clusters, which had been found in a previous study to have significant perfusion differences with moderate-severe OSA versus control, and found no significant difference in perfusion between the two groups. The perfusions were also very close, with means of 50.2 and 51.8 mL/100 g/min for the moderate-OSAs and controls, respectively, with a negligible effect size (Cohen's d = 0.10). CONCLUSION: We conclude that cerebral perfusion is not impaired in people with moderate OSA and that cerebral flow regulatory mechanisms can cope with the adverse effects which occur in moderate OSA. This is an important factor in clinical decisions for prescription of continuous positive airway pressure therapy (CPAP).


Asunto(s)
Circulación Cerebrovascular , Polisomnografía , Apnea Obstructiva del Sueño , Vigilia , Humanos , Apnea Obstructiva del Sueño/fisiopatología , Apnea Obstructiva del Sueño/terapia , Femenino , Persona de Mediana Edad , Masculino , Adulto , Anciano , Circulación Cerebrovascular/fisiología , Vigilia/fisiología , Imagen por Resonancia Magnética , Valores de Referencia , Encéfalo/fisiopatología , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen
20.
BMC Geriatr ; 24(1): 527, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886640

RESUMEN

BACKGROUND: A range of strategies are available that can improve the outcomes of older persons particularly in relation to basic activities of daily living during and after an acute care (AC) episode. This paper outlines the original development of outcome-oriented quality indicators (QIs) in relation to common geriatric syndromes and function for the care of the frail aged hospitalized in acute general medical wards. METHODS: Design QIs were developed using evidence from literature, expert opinion, field study data and a formal voting process. A systematic literature review of literature identified existing QIs (there were no outcome QIs) and evidence of interventions that improve older persons' outcomes in AC. Preliminary indicators were developed by two expert panels following consideration of the evidence. After analysis of the data from field testing (indicator prevalence, variability across sites), panel meetings refined the QIs prior to a formal voting process. SETTING: Data was collected in nine Australian general medical wards. PARTICIPANTS: Patients aged 70 years and over, consented within 24 h of admission to the AC ward. MEASUREMENTS: The interRAI Acute Care - Comprehensive Geriatric Assessment (interRAI AC-CGA) was administered at admission and discharge; a daily risk assessment in hospital; 28-day phone follow-up and chart audit. RESULTS: Ten outcome QIs were established which focused on common geriatric syndromes and function for the care of the frail aged hospitalized in acute general medical wards. CONCLUSION: Ten outcome QIs were developed. These QIs can be used to identify areas where specific action will lead to improvements in the quality of care delivered to older persons in hospital.


Asunto(s)
Evaluación Geriátrica , Indicadores de Calidad de la Atención de Salud , Humanos , Anciano , Indicadores de Calidad de la Atención de Salud/normas , Anciano de 80 o más Años , Evaluación Geriátrica/métodos , Femenino , Masculino , Actividades Cotidianas , Hospitalización , Anciano Frágil , Evaluación del Resultado de la Atención al Paciente
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