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1.
Nature ; 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39358512

RESUMEN

The western boundary currents are characterized by narrow, intense ocean jets and are among the most energetic phenomena in the world ocean. The importance of the western boundary currents to the mean climate is well established: they transport vast quantities of heat from the subtropics to the midlatitudes1, and they govern the structure of the climatological mean surface winds2-6, precipitation4-6 and extratropical storm tracks7-13. Their importance to climate variability is much less clear, as the tropospheric response to extratropical sea surface temperature (SST) variability is generally modest relative to the internal variability in the midlatitude atmosphere12-14. Here we exploit novel local analyses based on high-spatial-resolution data to demonstrate that SST variability in the western boundary currents has a more robust signature in climate variability than has been indicated in previous work. Our results indicate that warm SST anomalies in the major boundary currents of both hemispheres are associated with a distinct signature of locally enhanced precipitation and rising motion anomalies that extend throughout the depth of the troposphere. The tropospheric signature closely mirrors that of ocean dynamical processes in the boundary currents. Thus, the findings indicate a distinct and robust pathway through which extratropical ocean dynamical processes influence local climate variability. The observational relationships are also reproducible in Earth system model simulations but only when the simulations are run at high spatial resolution.

2.
Nature ; 604(7904): 65-71, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35388197

RESUMEN

With the scaling of lateral dimensions in advanced transistors, an increased gate capacitance is desirable both to retain the control of the gate electrode over the channel and to reduce the operating voltage1. This led to a fundamental change in the gate stack in 2008, the incorporation of high-dielectric-constant HfO2 (ref. 2), which remains the material of choice to date. Here we report HfO2-ZrO2 superlattice heterostructures as a gate stack, stabilized with mixed ferroelectric-antiferroelectric order, directly integrated onto Si transistors, and scaled down to approximately 20 ångströms, the same gate oxide thickness required for high-performance transistors. The overall equivalent oxide thickness in metal-oxide-semiconductor capacitors is equivalent to an effective SiO2 thickness of approximately 6.5 ångströms. Such a low effective oxide thickness and the resulting large capacitance cannot be achieved in conventional HfO2-based high-dielectric-constant gate stacks without scavenging the interfacial SiO2, which has adverse effects on the electron transport and gate leakage current3. Accordingly, our gate stacks, which do not require such scavenging, provide substantially lower leakage current and no mobility degradation. This work demonstrates that ultrathin ferroic HfO2-ZrO2 multilayers, stabilized with competing ferroelectric-antiferroelectric order in the two-nanometre-thickness regime, provide a path towards advanced gate oxide stacks in electronic devices beyond conventional HfO2-based high-dielectric-constant materials.

3.
Nature ; 599(7885): 425-430, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34789900

RESUMEN

Climate change has been and will be accompanied by widespread changes in surface temperature. It is clear that these changes include global-wide increases in mean surface temperature and changes in temperature variance that are more regionally-dependent1-3. It is less clear whether they also include changes in the persistence of surface temperature. This is important as the effects of weather events on ecosystems and society depend critically on the length of the event. Here we provide an extensive survey of the response of surface temperature persistence to climate change over the twenty-first century from the output of 150 simulations run on four different Earth system models, and from simulations run on simplified models with varying representations of radiative processes and large-scale dynamics. Together, the results indicate that climate change simulations are marked by widespread changes in surface temperature persistence that are generally most robust over ocean areas and arise due to a seemingly broad range of physical processes. The findings point to both the robustness of widespread changes in persistence under climate change, and the critical need to better understand, simulate and constrain such changes.


Asunto(s)
Cambio Climático/estadística & datos numéricos , Modelos Climáticos , Temperatura , Calentamiento Global/prevención & control , Calentamiento Global/estadística & datos numéricos , Océanos y Mares , Factores de Tiempo
4.
Nature ; 580(7801): 87-92, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32238927

RESUMEN

Southern Ocean ecosystems are under pressure from resource exploitation and climate change1,2. Mitigation requires the identification and protection of Areas of Ecological Significance (AESs), which have so far not been determined at the ocean-basin scale. Here, using assemblage-level tracking of marine predators, we identify AESs for this globally important region and assess current threats and protection levels. Integration of more than 4,000 tracks from 17 bird and mammal species reveals AESs around sub-Antarctic islands in the Atlantic and Indian Oceans and over the Antarctic continental shelf. Fishing pressure is disproportionately concentrated inside AESs, and climate change over the next century is predicted to impose pressure on these areas, particularly around the Antarctic continent. At present, 7.1% of the ocean south of 40°S is under formal protection, including 29% of the total AESs. The establishment and regular revision of networks of protection that encompass AESs are needed to provide long-term mitigation of growing pressures on Southern Ocean ecosystems.


Asunto(s)
Sistemas de Identificación Animal , Organismos Acuáticos/fisiología , Cambio Climático/estadística & datos numéricos , Conservación de los Recursos Naturales/métodos , Ecosistema , Océanos y Mares , Conducta Predatoria , Animales , Regiones Antárticas , Biodiversidad , Aves , Peces , Cadena Alimentaria , Cubierta de Hielo , Mamíferos , Dinámica Poblacional
5.
Proc Natl Acad Sci U S A ; 120(20): e2300758120, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37155871

RESUMEN

In 1967, scientists used a simple climate model to predict that human-caused increases in atmospheric CO2 should warm Earth's troposphere and cool the stratosphere. This important signature of anthropogenic climate change has been documented in weather balloon and satellite temperature measurements extending from near-surface to the lower stratosphere. Stratospheric cooling has also been confirmed in the mid to upper stratosphere, a layer extending from roughly 25 to 50 km above the Earth's surface (S25 - 50). To date, however, S25 - 50 temperatures have not been used in pattern-based attribution studies of anthropogenic climate change. Here, we perform such a "fingerprint" study with satellite-derived patterns of temperature change that extend from the lower troposphere to the upper stratosphere. Including S25 - 50 information increases signal-to-noise ratios by a factor of five, markedly enhancing fingerprint detectability. Key features of this global-scale human fingerprint include stratospheric cooling and tropospheric warming at all latitudes, with stratospheric cooling amplifying with height. In contrast, the dominant modes of internal variability in S25 - 50 have smaller-scale temperature changes and lack uniform sign. These pronounced spatial differences between S25 - 50 signal and noise patterns are accompanied by large cooling of S25 - 50 (1 to 2[Formula: see text]C over 1986 to 2022) and low S25 - 50 noise levels. Our results explain why extending "vertical fingerprinting" to the mid to upper stratosphere yields incontrovertible evidence of human effects on the thermal structure of Earth's atmosphere.

6.
J Biol Chem ; 300(4): 107156, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38479601

RESUMEN

Mechanically activated Piezo1 channels undergo transitions from closed to open-state in response to pressure and other mechanical stimuli. However, the molecular details of these mechanosensitive gating transitions are unknown. Here, we used cell-attached pressure-clamp recordings to acquire single channel data at steady-state conditions (where inactivation has settled down), at various pressures and voltages. Importantly, we identify and analyze subconductance states of the channel which were not reported before. Pressure-dependent activation of Piezo1 increases the occupancy of open and subconductance state at the expense of decreased occupancy of shut-states. No significant change in the mean open time of subconductance states was observed with increasing negative pipette pressure or with varying voltages (ranging from -40 to -100 mV). Using Markov-chain modeling, we identified a minimal four-states kinetic scheme, which recapitulates essential characteristics of the single channel data, including that of the subconductance level. This study advances our understanding of Piezo1-gating mechanism in response to discrete stimuli (such as pressure and voltage) and paves the path to develop cellular and tissue level models to predict Piezo1 function in various cell types.


Asunto(s)
Activación del Canal Iónico , Canales Iónicos , Mecanotransducción Celular , Presión , Humanos , Células HEK293 , Activación del Canal Iónico/fisiología , Canales Iónicos/metabolismo , Cinética , Cadenas de Markov
7.
Nature ; 575(7781): 180-184, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31695210

RESUMEN

Methane is a powerful greenhouse gas and is targeted for emissions mitigation by the US state of California and other jurisdictions worldwide1,2. Unique opportunities for mitigation are presented by point-source emitters-surface features or infrastructure components that are typically less than 10 metres in diameter and emit plumes of highly concentrated methane3. However, data on point-source emissions are sparse and typically lack sufficient spatial and temporal resolution to guide their mitigation and to accurately assess their magnitude4. Here we survey more than 272,000 infrastructure elements in California using an airborne imaging spectrometer that can rapidly map methane plumes5-7. We conduct five campaigns over several months from 2016 to 2018, spanning the oil and gas, manure-management and waste-management sectors, resulting in the detection, geolocation and quantification of emissions from 564 strong methane point sources. Our remote sensing approach enables the rapid and repeated assessment of large areas at high spatial resolution for a poorly characterized population of methane emitters that often appear intermittently and stochastically. We estimate net methane point-source emissions in California to be 0.618 teragrams per year (95 per cent confidence interval 0.523-0.725), equivalent to 34-46 per cent of the state's methane inventory8 for 2016. Methane 'super-emitter' activity occurs in every sector surveyed, with 10 per cent of point sources contributing roughly 60 per cent of point-source emissions-consistent with a study of the US Four Corners region that had a different sectoral mix9. The largest methane emitters in California are a subset of landfills, which exhibit persistent anomalous activity. Methane point-source emissions in California are dominated by landfills (41 per cent), followed by dairies (26 per cent) and the oil and gas sector (26 per cent). Our data have enabled the identification of the 0.2 per cent of California's infrastructure that is responsible for these emissions. Sharing these data with collaborating infrastructure operators has led to the mitigation of anomalous methane-emission activity10.


Asunto(s)
Monitoreo del Ambiente , Metano/análisis , Administración de Residuos , California , Efecto Invernadero , Estiércol , Metano/química , Metano/metabolismo , Gas Natural , Industria del Petróleo y Gas/métodos , Petróleo , Aguas Residuales
8.
Hum Genomics ; 17(1): 57, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37420280

RESUMEN

Alzheimer's disease (AD) poses a profound human, social, and economic burden. Previous studies suggest that extra virgin olive oil (EVOO) may be helpful in preventing cognitive decline. Here, we present a network machine learning method for identifying bioactive phytochemicals in EVOO with the highest potential to impact the protein network linked to the development and progression of the AD. A balanced classification accuracy of 70.3 ± 2.6% was achieved in fivefold cross-validation settings for predicting late-stage experimental drugs targeting AD from other clinically approved drugs. The calibrated machine learning algorithm was then used to predict the likelihood of existing drugs and known EVOO phytochemicals to be similar in action to the drugs impacting AD protein networks. These analyses identified the following ten EVOO phytochemicals with the highest likelihood of being active against AD: quercetin, genistein, luteolin, palmitoleate, stearic acid, apigenin, epicatechin, kaempferol, squalene, and daidzein (in the order from the highest to the lowest likelihood). This in silico study presents a framework that brings together artificial intelligence, analytical chemistry, and omics studies to identify unique therapeutic agents. It provides new insights into how EVOO constituents may help treat or prevent AD and potentially provide a basis for consideration in future clinical studies.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Aceite de Oliva/uso terapéutico , Aceite de Oliva/química , Inteligencia Artificial , Aprendizaje Automático
9.
Hum Genomics ; 17(1): 80, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37641126

RESUMEN

Over the last century, outbreaks and pandemics have occurred with disturbing regularity, necessitating advance preparation and large-scale, coordinated response. Here, we developed a machine learning predictive model of disease severity and length of hospitalization for COVID-19, which can be utilized as a platform for future unknown viral outbreaks. We combined untargeted metabolomics on plasma data obtained from COVID-19 patients (n = 111) during hospitalization and healthy controls (n = 342), clinical and comorbidity data (n = 508) to build this patient triage platform, which consists of three parts: (i) the clinical decision tree, which amongst other biomarkers showed that patients with increased eosinophils have worse disease prognosis and can serve as a new potential biomarker with high accuracy (AUC = 0.974), (ii) the estimation of patient hospitalization length with ± 5 days error (R2 = 0.9765) and (iii) the prediction of the disease severity and the need of patient transfer to the intensive care unit. We report a significant decrease in serotonin levels in patients who needed positive airway pressure oxygen and/or were intubated. Furthermore, 5-hydroxy tryptophan, allantoin, and glucuronic acid metabolites were increased in COVID-19 patients and collectively they can serve as biomarkers to predict disease progression. The ability to quickly identify which patients will develop life-threatening illness would allow the efficient allocation of medical resources and implementation of the most effective medical interventions. We would advocate that the same approach could be utilized in future viral outbreaks to help hospitals triage patients more effectively and improve patient outcomes while optimizing healthcare resources.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Triaje , Alantoína , Brotes de Enfermedades , Aprendizaje Automático
10.
Biomacromolecules ; 25(1): 272-281, 2024 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-38118170

RESUMEN

Elastin-like polypeptides (ELP) are a class of materials that are widely used as purification tags and in potential therapeutic applications. We have used the hydrophobic nature of ELP to extract them into organic solvents and precipitate them to obtain highly pure materials. Although many different types of ELP have been rapidly purified in this manner, the underlying mechanism for this process and its ability to retain functional proteins within organic phase-rich media has been unclear. A cleavable ELP-Intein construct fused with the enzyme chorismate mutase (ELP-I-Cm2) was used to better understand the organic solvent extraction process for ELP and the factors impacting the retention of enzyme activity. Our extraction studies indicated that a cell lysis step was essential to stabilize the ELP-I-Cm2 in the organic phase, prevent intein cleavage, and extract the fusion protein with high efficiency and retained activity. Circular dichroism and infrared spectroscopic characterization of ELP-I-Cm2 in organic solvents and aqueous solutions of the extracted and precipitated material indicated that the ELP secondary structure was retained in both environments. Atomic force microscopy and negative stain transmission electron microscopy imaging of ELP-I-Cm2 in organic solvents revealed highly regular circular features that were ∼50 nm in diameter, in contrast to larger (>100 nm) irregular features found in aqueous solutions. Since reverse micelles have often been used in catalytic processes, we evaluated the enzymatic activity of the ELP-I-Cm2 reversed micelles in different organic solvent mixtures and found that Cm2-mediated reactions in organic media were of comparable rate and efficiency to those in aqueous media. Based on these findings, we report an exciting new opportunity for ELP-enzyme fusion applications by exploiting their ability to form catalytically active reverse micelles in organic media.


Asunto(s)
Polipéptidos Similares a Elastina , Micelas , Péptidos/química , Elastina/química , Solventes , Proteínas Recombinantes de Fusión
11.
Biomacromolecules ; 25(9): 5729-5744, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39185801

RESUMEN

Nucleic acid (NA)-based therapies are revolutionizing biomedical research through their ability to control cellular functions at the genetic level. This work demonstrates a versatile elastin-like polypeptide (ELP) carrier system using a layer-by-layer (LbL) formulation approach that delivers NA cargos ranging in size from siRNA to plasmids. The components of the system can be reconfigured to modulate the biochemical and biophysical characteristics of the carrier for engaging the unique features of the biological target. We show the physical characterization and biological performance of LbL ELP nucleic acid nanoparticles (LENNs) in murine and human bladder tumor cell lines. Targeting bladder tumors is difficult owing to the constant influx of urine into the bladder, leading to low contact times (typically <2 h) for therapeutic agents delivered via intravesical instillation. LENN complexes bind to bladder tumor cells within 30 min and become rapidly internalized to release their NA cargo within 60 min. Our data show that a readily adaptable NA-delivery system has been created that is flexible in its targeting ability, cargo size, and disassembly kinetics. This approach provides an alternative path to either lipid nanoparticle formulations that suffer from inefficiency and physicochemical instability or viral vectors that are plagued by manufacturing and immune rejection challenges. This agile ELP-based nanocarrier provides an alternative route for nucleic acid delivery using a biomanufacturable, biodegradable, biocompatible, and highly tunable vehicle capable of targeting cells via engagement with overexpressed cell surface receptors.


Asunto(s)
Elastina , Nanopartículas , Neoplasias de la Vejiga Urinaria , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Humanos , Elastina/química , Ratones , Animales , Nanopartículas/química , Línea Celular Tumoral , Receptores ErbB/metabolismo , Receptores ErbB/genética , Péptidos/química , Ácidos Nucleicos/química , Ácidos Nucleicos/administración & dosificación , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/química , Polipéptidos Similares a Elastina
12.
Dis Colon Rectum ; 67(7): 977-984, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38653495

RESUMEN

BACKGROUND: The long-term effects of Hirschsprung disease are clinically variable. An improved understanding of challenges patients may face as adults can help inform transitional care management. OBJECTIVE: To explore the outcomes and transitional care experiences in adult patients with Hirschsprung. DESIGN: Cohort study. SETTING: Single center. PATIENTS: All patients treated for Hirschsprung between 1977 and 2001 (aged older than 18 years at the time of survey distribution in July 2018-2019). Eligible patients were sent validated multidomain surveys and qualitative questions regarding their transitional care. MAIN OUTCOME MEASURES: Status of transitional care, bowel function, and quality-of-life assessment. Qualitative analysis of transitional care experience. RESULTS: Of 139 patients, 20 had received transition care (10 had at least 1 visit but had been discharged and 10 were receiving ongoing follow-up). These patients had inferior bowel function and quality-of-life scores at follow-up. Twenty-three patients (17%) had issues with soiling at the time of discharge, and 7 patients received transitional care. Of these 23 patients, 9 (39%) had a normal Bowel Function Score (17 or more), 5 (22%) had a poor score (less than 12), and 1 had since had a stoma formation. Eighteen patients (13%) had active moderate-severe issues related to bowel function, only 5 had been transitioned, and just 2 remained under ongoing care. Importantly, when these patients were discharged from our pediatric center, at a median age of 14 (interquartile range, 12-16) years, 10 of 17 patients had no perceptible bowel issues, suggesting a worsening of function after discharge. LIMITATIONS: The retrospective design and reliance on clinical notes to gather information on discharge status as well as patient recall of events. CONCLUSIONS: There remains a small but significant proportion of Hirschsprung patients for whom bowel function either remains or becomes a major burden. These results support a need to better stratify patients requiring transitional care and ensure a clear route to care if their status changes after discharge. See Video Abstract . ATENCIN DE TRANSICIN EN PACIENTES CON ENFERMEDAD DE HIRSCHSPRUNG, LOS QUE SE QUEDAN ATRS: ANTECEDENTES:Los efectos a largo plazo de la enfermedad de Hirschsprung son clínicamente variables. Una mejor comprensión de los desafíos que los pacientes pueden enfrentar cuando sean adultos puede ayudar a informar la gestión de la atención de transición.OBJETIVO:Explorar los resultados y las experiencias de atención de transición en pacientes adultos con Hirschsprung.DISEÑO:Estudio de cohorte.AJUSTE:Unico centro.PACIENTES:Todos los pacientes tratados por Hirschsprung 1977-2001 (edad >18 años en el momento de la encuesta, Julio de 2018-2019). A los pacientes elegibles se les enviaron encuestas multidominio validadas, así como preguntas cualitativas sobre su atención de transición.PRINCIPALES MEDIDAS DE RESULTADOS:Estado de la atención de transición, función intestinal y evaluación de la calidad de vida. Análisis cualitativo de la experiencia de cuidados transicionales.RESULTADOS:De 139 pacientes, 20 habían recibido atención de transición (10 tuvieron al menos una visita pero habían sido dados de alta y 10 estaban recibiendo seguimiento continuo). Estos pacientes tenían puntuaciones inferiores de función intestinal y calidad de vida en el seguimiento. Veintitrés (17%) pacientes tuvieron problemas para ensuciarse en el momento del alta y 7 recibieron atención de transición. De estos, 9/23 (39%) tenían una puntuación de función intestinal normal (≥17), 5/23 (22%) tenían una puntuación baja (<12) y un paciente había tenido desde entonces una formación de estoma. Dieciocho (13%) pacientes tenían problemas activos de moderados a graves relacionados con la función intestinal, solo cinco habían realizado la transición y solo 2 permanecían bajo atención continua. Es importante destacar que cuando estos pacientes fueron dados de alta de nuestro centro pediátrico, a una edad promedio de 14 [RIQ 12-16] años, 10/17 no tenían problemas intestinales perceptibles, lo que sugiere un empeoramiento de la función después del alta.LIMITACIONES:El diseño retrospectivo y la dependencia de notas clínicas para recopilar información sobre el estado del alta, así como el recuerdo de los eventos por parte del paciente.CONCLUSIÓN:Sigue existiendo una proporción pequeña pero significativa de pacientes con Hirschsprung para quienes la función intestinal permanece o se convierte en una carga importante. Estos resultados respaldan la necesidad de estratificar mejor a los pacientes que requieren atención de transición y garantizar una ruta clara hacia la atención si su estado cambia después del alta. ( Traducción-Dr. Yesenia Rojas-Khalil ).


Asunto(s)
Enfermedad de Hirschsprung , Calidad de Vida , Humanos , Enfermedad de Hirschsprung/terapia , Enfermedad de Hirschsprung/cirugía , Masculino , Femenino , Adulto , Adolescente , Cuidado de Transición/organización & administración , Adulto Joven , Incontinencia Fecal/terapia , Incontinencia Fecal/etiología , Transición a la Atención de Adultos , Estudios Retrospectivos , Estudios de Cohortes , Encuestas y Cuestionarios
13.
Inorg Chem ; 63(40): 18981-18991, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39328180

RESUMEN

Nickel phosphides are of particular interest because they are highly active and stable catalysts for petroleum/biorefinery and hydrogen production. Despite their significant catalytic potential, synthesizing various phase-pure nickel phosphide nanoparticles of uniform size remains a challenge. In this work, we develop a robust trioctylphosphine (TOP)-mediated route to make highly uniform phase-pure Ni12P5, Ni2P, and Ni5P4 nanoparticles. The synthetic route forms amorphous Ni70P30 nanoparticle intermediates. The reactions can be stopped at the amorphous stage when amorphous particles are desired. The amount of P incorporation can be controlled by varying the ratio of TOP to Ni(II). The mechanism for composition control involves the competition of the kinetics of two processes: the addition of the reduced Ni and the incorporation of P into Ni. Uniform Ni70P30 amorphous nanoparticles can be generated at a high TOP-to-Ni(II) ratio, where the P incorporation kinetics is made to dominate. Ni70P30 can later be transformed into phase-pure Ni12P5, Ni2P, and Ni5P4 nanocrystals of uniform size. The transformation can be controlled precisely by modulating the temperature. A UV-vis study coupled with theoretical modeling reveals Ni(0)-TOPx complexes along the synthetic path. This approach may be expanded to create other metal compounds, potentially enabling the synthesis of uniform nanoparticles of a greater variety.

14.
Transpl Int ; 37: 13191, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39015154

RESUMEN

Little is known either about either physical activity patterns, or other lifestyle-related prevention measures in heart transplantation (HTx) recipients. The history of HTx started more than 50 years ago but there are still no guidelines or position papers highlighting the features of prevention and rehabilitation after HTx. The aims of this scientific statement are (i) to explain the importance of prevention and rehabilitation after HTx, and (ii) to promote the factors (modifiable/non-modifiable) that should be addressed after HTx to improve patients' physical capacity, quality of life and survival. All HTx team members have their role to play in the care of these patients and multidisciplinary prevention and rehabilitation programmes designed for transplant recipients. HTx recipients are clearly not healthy disease-free subjects yet they also significantly differ from heart failure patients or those who are supported with mechanical circulatory support. Therefore, prevention and rehabilitation after HTx both need to be specifically tailored to this patient population and be multidisciplinary in nature. Prevention and rehabilitation programmes should be initiated early after HTx and continued during the entire post-transplant journey. This clinical consensus statement focuses on the importance and the characteristics of prevention and rehabilitation designed for HTx recipients.


Asunto(s)
Insuficiencia Cardíaca , Trasplante de Corazón , Calidad de Vida , Humanos , Consenso , Europa (Continente) , Ejercicio Físico , Insuficiencia Cardíaca/rehabilitación , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/efectos adversos , Sociedades Médicas
15.
Nature ; 553(7687): 217-221, 2018 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-29258297

RESUMEN

Although genetic factors contribute to almost half of all cases of deafness, treatment options for genetic deafness are limited. We developed a genome-editing approach to target a dominantly inherited form of genetic deafness. Here we show that cationic lipid-mediated in vivo delivery of Cas9-guide RNA complexes can ameliorate hearing loss in a mouse model of human genetic deafness. We designed and validated, both in vitro and in primary fibroblasts, genome editing agents that preferentially disrupt the dominant deafness-associated allele in the Tmc1 (transmembrane channel-like gene family 1) Beethoven (Bth) mouse model, even though the mutant Tmc1Bth allele differs from the wild-type allele at only a single base pair. Injection of Cas9-guide RNA-lipid complexes targeting the Tmc1Bth allele into the cochlea of neonatal Tmc1Bth/+ mice substantially reduced progressive hearing loss. We observed higher hair cell survival rates and lower auditory brainstem response thresholds in injected ears than in uninjected ears or ears injected with control complexes that targeted an unrelated gene. Enhanced acoustic startle responses were observed among injected compared to uninjected Tmc1Bth/+ mice. These findings suggest that protein-RNA complex delivery of target gene-disrupting agents in vivo is a potential strategy for the treatment of some types of autosomal-dominant hearing loss.


Asunto(s)
Proteínas Asociadas a CRISPR/administración & dosificación , Edición Génica/métodos , Genes Dominantes/genética , Terapia Genética/métodos , Pérdida Auditiva/genética , Estimulación Acústica , Alelos , Animales , Animales Recién Nacidos , Umbral Auditivo , Secuencia de Bases , Proteínas Asociadas a CRISPR/metabolismo , Proteínas Asociadas a CRISPR/uso terapéutico , Sistemas CRISPR-Cas , Supervivencia Celular , Cóclea/citología , Cóclea/metabolismo , Modelos Animales de Enfermedad , Potenciales Evocados Auditivos del Tronco Encefálico , Femenino , Fibroblastos , Células Ciliadas Auditivas/citología , Pérdida Auditiva/fisiopatología , Pérdida Auditiva/prevención & control , Humanos , Liposomas , Masculino , Proteínas de la Membrana/genética , Ratones , Reflejo de Sobresalto
16.
Cochrane Database Syst Rev ; 4: CD013508, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38577875

RESUMEN

BACKGROUND: Depression and anxiety occur frequently (with reported prevalence rates of around 40%) in individuals with coronary heart disease (CHD), heart failure (HF) or atrial fibrillation (AF) and are associated with a poor prognosis, such as decreased health-related quality of life (HRQoL), and increased morbidity and mortality. Psychological interventions are developed and delivered by psychologists or specifically trained healthcare workers and commonly include cognitive behavioural therapies and mindfulness-based stress reduction. They have been shown to reduce depression and anxiety in the general population, though the exact mechanism of action is not well understood. Further, their effects on psychological and clinical outcomes in patients with CHD, HF or AF are unclear. OBJECTIVES: To assess the effects of psychological interventions (alone, or with cardiac rehabilitation or pharmacotherapy, or both) in adults who have a diagnosis of CHD, HF or AF, compared to no psychological intervention, on psychological and clinical outcomes. SEARCH METHODS: We searched the CENTRAL, MEDLINE, Embase, PsycINFO and CINAHL databases from 2009 to July 2022. We also searched three clinical trials registers in September 2020, and checked the reference lists of included studies. No language restrictions were applied. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing psychological interventions with no psychological intervention for a minimum of six months follow-up in adults aged over 18 years with a clinical diagnosis of CHD, HF or AF, with or without depression or anxiety. Studies had to report on either depression or anxiety or both. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were depression and anxiety, and our secondary outcomes of interest were HRQoL mental and physical components, all-cause mortality and major adverse cardiovascular events (MACE). We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: Twenty-one studies (2591 participants) met our inclusion criteria. Sixteen studies included people with CHD, five with HF and none with AF. Study sample sizes ranged from 29 to 430. Twenty and 17 studies reported the primary outcomes of depression and anxiety, respectively. Despite the high heterogeneity and variation, we decided to pool the studies using a random-effects model, recognising that the model does not eliminate heterogeneity and findings should be interpreted cautiously. We found that psychological interventions probably have a moderate effect on reducing depression (standardised mean difference (SMD) -0.36, 95% confidence interval (CI) -0.65 to -0.06; 20 studies, 2531 participants; moderate-certainty evidence) and anxiety (SMD -0.57, 95% CI -0.96 to -0.18; 17 studies, 2235 participants; moderate-certainty evidence), compared to no psychological intervention. Psychological interventions may have little to no effect on HRQoL physical component summary scores (PCS) (SMD 0.48, 95% CI -0.02 to 0.98; 12 studies, 1454 participants; low-certainty evidence), but may have a moderate effect on improving HRQoL mental component summary scores (MCS) (SMD 0.63, 95% CI 0.01 to 1.26; 12 studies, 1454 participants; low-certainty evidence), compared to no psychological intervention. Psychological interventions probably have little to no effect on all-cause mortality (risk ratio (RR) 0.81, 95% CI 0.39 to 1.69; 3 studies, 615 participants; moderate-certainty evidence) and may have little to no effect on MACE (RR 1.22, 95% CI 0.77 to 1.92; 4 studies, 450 participants; low-certainty evidence), compared to no psychological intervention. AUTHORS' CONCLUSIONS: Current evidence suggests that psychological interventions for depression and anxiety probably result in a moderate reduction in depression and anxiety and may result in a moderate improvement in HRQoL MCS, compared to no intervention. However, they may have little to no effect on HRQoL PCS and MACE, and probably do not reduce mortality (all-cause) in adults who have a diagnosis of CHD or HF, compared with no psychological intervention. There was moderate to substantial heterogeneity identified across studies. Thus, evidence of treatment effects on these outcomes warrants careful interpretation. As there were no studies of psychological interventions for patients with AF included in our review, this is a gap that needs to be addressed in future studies, particularly in view of the rapid growth of research on management of AF. Studies investigating cost-effectiveness, return to work and cardiovascular morbidity (revascularisation) are also needed to better understand the benefits of psychological interventions in populations with heart disease.


Asunto(s)
Fibrilación Atrial , Enfermedad Coronaria , Insuficiencia Cardíaca , Adulto , Humanos , Ansiedad/terapia , Ansiedad/psicología , Fibrilación Atrial/terapia , Depresión/terapia , Depresión/psicología , Insuficiencia Cardíaca/terapia , Intervención Psicosocial , Calidad de Vida
17.
Arch Toxicol ; 98(10): 3241-3257, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39192018

RESUMEN

1,4-Dioxane (DX), an emerging water contaminant, is classified as a Group 2B liver carcinogen based on animal studies. Understanding of the mechanisms of action of DX liver carcinogenicity is important for the risk assessment and control of this environmental pollution. Previous studies demonstrate that high-dose DX exposure in mice through drinking water for up to 3 months caused liver mild cytotoxicity and oxidative DNA damage, a process correlating with hepatic CYP2E1 induction and elevated oxidative stress. To access the role of CYP2E1 in DX metabolism and liver toxicity, in the current study, male and female Cyp2e1-null mice were exposed to DX in drinking water (5000 ppm) for 1 week or 3 months. DX metabolism, redox and molecular investigations were subsequently performed on male Cyp2e1-null mice for cross-study comparisons to similarly treated male wildtype (WT) and glutathione (GSH)-deficient Gclm-null mice. Our results show that Cyp2e1-null mice of both genders were resistant to DX-induced hepatocellular cytotoxicity. In male Cyp2e1-null mice exposed to DX for 3 months, firstly, DX metabolism to ß-hydroxyethoxyacetic acid was reduced to ~ 36% of WT levels; secondly, DX-induced hepatic redox dysregulation (lipid peroxidation, GSH oxidation, and activation of NRF2 antioxidant response) was substantially attenuated; thirdly, liver oxidative DNA damage was at a comparable level to DX-exposed WT mice, accompanied by suppression of DNA damage repair response; lastly, no aberrant proliferative or preneoplastic lesions were noted in DX-exposed livers. Overall, this study reveals, for the first time, that CYP2E1 is the main enzyme for DX metabolism at high dose and a primary contributor to DX-induced liver oxidative stress and associated cytotoxicity. High dose DX-induced genotoxicity may occur via CYP2E1-independent pathway(s), potentially involving impaired DNA damage repair.


Asunto(s)
Citocromo P-450 CYP2E1 , Dioxanos , Hígado , Ratones Noqueados , Estrés Oxidativo , Animales , Citocromo P-450 CYP2E1/metabolismo , Citocromo P-450 CYP2E1/genética , Masculino , Femenino , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Dioxanos/toxicidad , Estrés Oxidativo/efectos de los fármacos , Daño del ADN , Ratones , Ratones Endogámicos C57BL , Glutatión/metabolismo , Carcinógenos/toxicidad , Carcinógenos/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/patología
18.
Am J Respir Crit Care Med ; 207(4): 461-474, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36194662

RESUMEN

Rationale: Pediatric obesity-related asthma is a nonatopic asthma phenotype with high disease burden and few effective therapies. RhoGTPase upregulation in peripheral blood T helper (Th) cells is associated with the phenotype, but the mechanisms that underlie this association are not known. Objectives: To investigate the mechanisms by which upregulation of CDC42 (Cell Division Cycle 42), a RhoGTPase, in Th cells is associated with airway smooth muscle (ASM) biology. Methods: Chemotaxis of obese asthma and healthy-weight asthma Th cells, and their adhesion to obese and healthy-weight nonasthmatic ASM, was investigated. Transcriptomics and proteomics were used to determine the differential effect of obese and healthy-weight asthma Th cell adhesion to obese or healthy-weight ASM biology. Measurements and Main Results: Chemotaxis of obese asthma Th cells with CDC42 upregulation was resistant to CDC42 inhibition. Obese asthma Th cells were more adherent to obese ASM compared with healthy-weight asthma Th cells to healthy-weight ASM. Compared with coculture with healthy-weight ASM, obese asthma Th cell coculture with obese ASM was positively enriched for genes and proteins involved in actin cytoskeleton organization, transmembrane receptor protein kinase signaling, and cell mitosis, and negatively enriched for extracellular matrix organization. Targeted gene evaluation revealed upregulation of IFNG, TNF (tumor necrosis factor), and Cluster of Differentiation 247 (CD247) among Th cell genes, and of Ak strain transforming (AKT), Ras homolog family member A (RHOA), and CD38, with downregulation of PRKCA (Protein kinase C-alpha), among smooth muscle genes. Conclusions: Obese asthma Th cells have uninhibited chemotaxis and are more adherent to obese ASM, which is associated with upregulation of genes and proteins associated with smooth muscle proliferation and reciprocal nonatopic Th cell activation.


Asunto(s)
Asma , Linfocitos T CD4-Positivos , Músculo Liso , Obesidad Infantil , Humanos , Asma/metabolismo , Células Cultivadas , Músculo Liso/metabolismo , Músculo Liso/patología , Miocitos del Músculo Liso , Obesidad Infantil/complicaciones , Sistema Respiratorio/metabolismo , Linfocitos T Colaboradores-Inductores/metabolismo , Linfocitos T CD4-Positivos/metabolismo
19.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33723065

RESUMEN

The ocean is a reservoir for CFC-11, a major ozone-depleting chemical. Anthropogenic production of CFC-11 dramatically decreased in the 1990s under the Montreal Protocol, which stipulated a global phase out of production by 2010. However, studies raise questions about current overall emission levels and indicate unexpected increases of CFC-11 emissions of about 10 Gg ⋅ yr-1 after 2013 (based upon measured atmospheric concentrations and an assumed atmospheric lifetime). These findings heighten the need to understand processes that could affect the CFC-11 lifetime, including ocean fluxes. We evaluate how ocean uptake and release through 2300 affects CFC-11 lifetimes, emission estimates, and the long-term return of CFC-11 from the ocean reservoir. We show that ocean uptake yields a shorter total lifetime and larger inferred emission of atmospheric CFC-11 from 1930 to 2075 compared to estimates using only atmospheric processes. Ocean flux changes over time result in small but not completely negligible effects on the calculated unexpected emissions change (decreasing it by 0.4 ± 0.3 Gg ⋅ yr-1). Moreover, it is expected that the ocean will eventually become a source of CFC-11, increasing its total lifetime thereafter. Ocean outgassing should produce detectable increases in global atmospheric CFC-11 abundances by the mid-2100s, with emission of around 0.5 Gg ⋅ yr-1; this should not be confused with illicit production at that time. An illustrative model projection suggests that climate change is expected to make the ocean a weaker reservoir for CFC-11, advancing the detectable change in the global atmospheric mixing ratio by about 5 yr.


Asunto(s)
Atmósfera , Clorofluorocarburos/efectos adversos , Contaminantes Ambientales/efectos adversos , Océanos y Mares , Ozono , Cambio Climático , Monitoreo del Ambiente , Modelos Teóricos
20.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34782457

RESUMEN

Lipofuscin granules enclose mixtures of cross-linked proteins and lipids in proportions that depend on the tissue analyzed. Retinal lipofuscin is unique in that it contains mostly lipids with very little proteins. However, retinal lipofuscin also presents biological and physicochemical characteristics indistinguishable from conventional granules, including indigestibility, tendency to cause lysosome swelling that results in rupture or defective functions, and ability to trigger NLRP3 inflammation, a symptom of low-level disruption of lysosomes. In addition, like conventional lipofuscins, it appears as an autofluorescent pigment, considered toxic waste, and a biomarker of aging. Ocular lipofuscin accumulates in the retinal pigment epithelium (RPE), whereby it interferes with the support of the neuroretina. RPE cell death is the primary cause of blindness in the most prevalent incurable genetic and age-related human disorders, Stargardt disease and age-related macular degeneration (AMD), respectively. Although retinal lipofuscin is directly linked to the cell death of the RPE in Stargardt, the extent to which it contributes to AMD is a matter of debate. Nonetheless, the number of AMD clinical trials that target lipofuscin formation speaks for the potential relevance for AMD as well. Here, we show that retinal lipofuscin triggers an atypical necroptotic cascade, amenable to pharmacological intervention. This pathway is distinct from canonic necroptosis and is instead dependent on the destabilization of lysosomes. We also provide evidence that necroptosis is activated in aged human retinas with AMD. Overall, this cytotoxicity mechanism may offer therapeutic targets and markers for genetic and age-related diseases associated with lipofuscin buildups.


Asunto(s)
Membranas Intracelulares/metabolismo , Lipofuscina/farmacología , Lisosomas/metabolismo , Necroptosis/efectos de los fármacos , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Envejecimiento , Oxidorreductasas de Alcohol , Animales , Muerte Celular , Humanos , Lipofuscina/metabolismo , Degeneración Macular/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Retina/metabolismo , Epitelio Pigmentado de la Retina/metabolismo
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