Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.844
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 187(10): 2521-2535.e21, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38697107

RESUMO

Cancer immunotherapy remains limited by poor antigenicity and a regulatory tumor microenvironment (TME). Here, we create "onion-like" multi-lamellar RNA lipid particle aggregates (LPAs) to substantially enhance the payload packaging and immunogenicity of tumor mRNA antigens. Unlike current mRNA vaccine designs that rely on payload packaging into nanoparticle cores for Toll-like receptor engagement in immune cells, systemically administered RNA-LPAs activate RIG-I in stromal cells, eliciting massive cytokine/chemokine response and dendritic cell/lymphocyte trafficking that provokes cancer immunogenicity and mediates rejection of both early- and late-stage murine tumor models. In client-owned canines with terminal gliomas, RNA-LPAs improved survivorship and reprogrammed the TME, which became "hot" within days of a single infusion. In a first-in-human trial, RNA-LPAs elicited rapid cytokine/chemokine release, immune activation/trafficking, tissue-confirmed pseudoprogression, and glioma-specific immune responses in glioblastoma patients. These data support RNA-LPAs as a new technology that simultaneously reprograms the TME while eliciting rapid and enduring cancer immunotherapy.


Assuntos
Imunoterapia , Lipídeos , RNA , Microambiente Tumoral , Animais , Cães , Feminino , Humanos , Camundongos , Antígenos de Neoplasias/imunologia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/imunologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/uso terapêutico , Linhagem Celular Tumoral , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Glioblastoma/terapia , Glioblastoma/imunologia , Glioma/terapia , Glioma/imunologia , Imunoterapia/métodos , Camundongos Endogâmicos C57BL , Neoplasias/terapia , Neoplasias/imunologia , RNA/química , RNA/uso terapêutico , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Lipídeos/química
2.
N Engl J Med ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39225258

RESUMO

BACKGROUND: Despite consistent recommendations from clinical guidelines, data from randomized trials on a long-term antithrombotic treatment strategy for patients with atrial fibrillation and stable coronary artery disease are still lacking. METHODS: We conducted a multicenter, open-label, adjudicator-masked, randomized trial comparing edoxaban monotherapy with dual antithrombotic therapy (edoxaban plus a single antiplatelet agent) in patients with atrial fibrillation and stable coronary artery disease (defined as coronary artery disease previously treated with revascularization or managed medically). The risk of stroke was assessed on the basis of the CHA2DS2-VASc score (scores range from 0 to 9, with higher scores indicating a greater risk of stroke). The primary outcome was a composite of death from any cause, myocardial infarction, stroke, systemic embolism, unplanned urgent revascularization, and major bleeding or clinically relevant nonmajor bleeding at 12 months. Secondary outcomes included a composite of major ischemic events and the safety outcome of major bleeding or clinically relevant nonmajor bleeding. RESULTS: We assigned 524 patients to the edoxaban monotherapy group and 516 patients to the dual antithrombotic therapy group at 18 sites in South Korea. The mean age of the patients was 72.1 years, 22.9% were women, and the mean CHA2DS2-VASc score was 4.3. At 12 months, a primary-outcome event had occurred in 34 patients (Kaplan-Meier estimate, 6.8%) assigned to edoxaban monotherapy and in 79 patients (16.2%) assigned to dual antithrombotic therapy (hazard ratio, 0.44; 95% confidence interval [CI], 0.30 to 0.65; P<0.001). The cumulative incidence of major ischemic events at 12 months appeared to be similar in the trial groups. Major bleeding or clinically relevant nonmajor bleeding occurred in 23 patients (Kaplan-Meier estimate, 4.7%) in the edoxaban monotherapy group and in 70 patients (14.2%) in the dual antithrombotic therapy group (hazard ratio, 0.34; 95% CI, 0.22 to 0.53). CONCLUSIONS: In patients with atrial fibrillation and stable coronary artery disease, edoxaban monotherapy led to a lower risk of a composite of death from any cause, myocardial infarction, stroke, systemic embolism, unplanned urgent revascularization, or major bleeding or clinically relevant nonmajor bleeding at 12 months than dual antithrombotic therapy. (Funded by the CardioVascular Research Foundation and others; EPIC-CAD ClinicalTrials.gov number, NCT03718559.).

3.
Cell ; 149(3): 525-37, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22521361

RESUMO

Balanced chromosomal abnormalities (BCAs) represent a relatively untapped reservoir of single-gene disruptions in neurodevelopmental disorders (NDDs). We sequenced BCAs in patients with autism or related NDDs, revealing disruption of 33 loci in four general categories: (1) genes previously associated with abnormal neurodevelopment (e.g., AUTS2, FOXP1, and CDKL5), (2) single-gene contributors to microdeletion syndromes (MBD5, SATB2, EHMT1, and SNURF-SNRPN), (3) novel risk loci (e.g., CHD8, KIRREL3, and ZNF507), and (4) genes associated with later-onset psychiatric disorders (e.g., TCF4, ZNF804A, PDE10A, GRIN2B, and ANK3). We also discovered among neurodevelopmental cases a profoundly increased burden of copy-number variants from these 33 loci and a significant enrichment of polygenic risk alleles from genome-wide association studies of autism and schizophrenia. Our findings suggest a polygenic risk model of autism and reveal that some neurodevelopmental genes are sensitive to perturbation by multiple mutational mechanisms, leading to variable phenotypic outcomes that manifest at different life stages.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/genética , Aberrações Cromossômicas , Transtorno Autístico/diagnóstico , Transtorno Autístico/genética , Criança , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Quebra Cromossômica , Deleção Cromossômica , Variações do Número de Cópias de DNA , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Sistema Nervoso/crescimento & desenvolvimento , Esquizofrenia/genética , Análise de Sequência de DNA , Transdução de Sinais
4.
Nature ; 582(7812): 395-398, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32494010

RESUMO

Neuroprotectant strategies that have worked in rodent models of stroke have failed to provide protection in clinical trials. Here we show that the opposite circadian cycles in nocturnal rodents versus diurnal humans1,2 may contribute to this failure in translation. We tested three independent neuroprotective approaches-normobaric hyperoxia, the free radical scavenger α-phenyl-butyl-tert-nitrone (αPBN), and the N-methyl-D-aspartic acid (NMDA) antagonist MK801-in mouse and rat models of focal cerebral ischaemia. All three treatments reduced infarction in day-time (inactive phase) rodent models of stroke, but not in night-time (active phase) rodent models of stroke, which match the phase (active, day-time) during which most strokes occur in clinical trials. Laser-speckle imaging showed that the penumbra of cerebral ischaemia was narrower in the active-phase mouse model than in the inactive-phase model. The smaller penumbra was associated with a lower density of terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL)-positive dying cells and reduced infarct growth from 12 to 72 h. When we induced circadian-like cycles in primary mouse neurons, deprivation of oxygen and glucose triggered a smaller release of glutamate and reactive oxygen species, as well as lower activation of apoptotic and necroptotic mediators, in 'active-phase' than in 'inactive-phase' rodent neurons. αPBN and MK801 reduced neuronal death only in 'inactive-phase' neurons. These findings suggest that the influence of circadian rhythm on neuroprotection must be considered for translational studies in stroke and central nervous system diseases.


Assuntos
Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Modelos Animais de Doenças , Neurônios/patologia , Neuroproteção , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/prevenção & controle , Animais , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/prevenção & controle , Glucose/deficiência , Humanos , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Infarto da Artéria Cerebral Média/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxigênio , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/fisiopatologia , Pesquisa Translacional Biomédica , Falha de Tratamento
5.
Nature ; 583(7814): E14, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32533095

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

6.
Mol Biol Evol ; 41(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38267085

RESUMO

Cellular and physiological cycles are driven by endogenous pacemakers, the diurnal and circadian rhythms. Key functions such as cell cycle progression and cellular metabolism are under rhythmic regulation, thereby maintaining physiological homeostasis. The photoreceptors phytochrome and cryptochrome, in response to light cues, are central input pathways for physiological cycles in most photosynthetic organisms. However, among Archaeplastida, red algae are the only taxa that lack phytochromes. Current knowledge about oscillatory rhythms is primarily derived from model species such as Arabidopsis thaliana and Chlamydomonas reinhardtii in the Viridiplantae, whereas little is known about these processes in other clades of the Archaeplastida, such as the red algae (Rhodophyta). We used genome-wide expression profiling of the red seaweed Gracilariopsis chorda and identified 3,098 rhythmic genes. Here, we characterized possible cryptochrome-based regulation and photosynthetic/cytosolic carbon metabolism in this species. We found a large family of cryptochrome genes in G. chorda that display rhythmic expression over the diurnal cycle and may compensate for the lack of phytochromes in this species. The input pathway gates regulatory networks of carbon metabolism which results in a compact and efficient energy metabolism during daylight hours. The system in G. chorda is distinct from energy metabolism in most plants, which activates in the dark. The green lineage, in particular, land plants, balance water loss and CO2 capture in terrestrial environments. In contrast, red seaweeds maintain a reduced set of photoreceptors and a compact cytosolic carbon metabolism to thrive in the harsh abiotic conditions typical of intertidal zones.


Assuntos
Arabidopsis , Rodófitas , Alga Marinha , Alga Marinha/genética , Criptocromos/metabolismo , Rodófitas/genética , Ritmo Circadiano/genética , Arabidopsis/genética
7.
Blood ; 142(10): 887-902, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37267517

RESUMO

Mantle cell lymphoma (MCL) is an incurable B-cell malignancy with an overall poor prognosis, particularly for patients that progress on targeted therapies. Novel, more durable treatment options are needed for patients with MCL. Protein arginine methyltransferase 5 (PRMT5) is overexpressed in MCL and plays an important oncogenic role in this disease via epigenetic and posttranslational modification of cell cycle regulators, DNA repair genes, components of prosurvival pathways, and RNA splicing regulators. The mechanism of targeting PRMT5 in MCL remains incompletely characterized. Here, we report on the antitumor activity of PRMT5 inhibition in MCL using integrated transcriptomics of in vitro and in vivo models of MCL. Treatment with a selective small-molecule inhibitor of PRMT5, PRT-382, led to growth arrest and cell death and provided a therapeutic benefit in xenografts derived from patients with MCL. Transcriptional reprograming upon PRMT5 inhibition led to restored regulatory activity of the cell cycle (p-RB/E2F), apoptotic cell death (p53-dependent/p53-independent), and activation of negative regulators of B-cell receptor-PI3K/AKT signaling (PHLDA3, PTPROt, and PIK3IP1). We propose pharmacologic inhibition of PRMT5 for patients with relapsed/refractory MCL and identify MTAP/CDKN2A deletion and wild-type TP53 as biomarkers that predict a favorable response. Selective targeting of PRMT5 has significant activity in preclinical models of MCL and warrants further investigation in clinical trials.


Assuntos
Linfoma de Célula do Manto , Fosfatidilinositol 3-Quinases , Adulto , Humanos , Linhagem Celular Tumoral , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
8.
Nature ; 572(7771): 620-623, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31384042

RESUMO

Non-line-of-sight imaging allows objects to be observed when partially or fully occluded from direct view, by analysing indirect diffuse reflections off a secondary relay surface. Despite many potential applications1-9, existing methods lack practical usability because of limitations including the assumption of single scattering only, ideal diffuse reflectance and lack of occlusions within the hidden scene. By contrast, line-of-sight imaging systems do not impose any assumptions about the imaged scene, despite relying on the mathematically simple processes of linear diffractive wave propagation. Here we show that the problem of non-line-of-sight imaging can also be formulated as one of diffractive wave propagation, by introducing a virtual wave field that we term the phasor field. Non-line-of-sight scenes can be imaged from raw time-of-flight data by applying the mathematical operators that model wave propagation in a conventional line-of-sight imaging system. Our method yields a new class of imaging algorithms that mimic the capabilities of line-of-sight cameras. To demonstrate our technique, we derive three imaging algorithms, modelled after three different line-of-sight systems. These algorithms rely on solving a wave diffraction integral, namely the Rayleigh-Sommerfeld diffraction integral. Fast solutions to Rayleigh-Sommerfeld diffraction and its approximations are readily available, benefiting our method. We demonstrate non-line-of-sight imaging of complex scenes with strong multiple scattering and ambient light, arbitrary materials, large depth range and occlusions. Our method handles these challenging cases without explicitly inverting a light-transport model. We believe that our approach will help to unlock the potential of non-line-of-sight imaging and promote the development of relevant applications not restricted to laboratory conditions.

9.
Proc Natl Acad Sci U S A ; 119(15): e2110846119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35385353

RESUMO

Ebola virus (EBOV) disease is characterized by lymphopenia, breach in vascular integrity, cytokine storm, and multiorgan failure. The pathophysiology of organ involvement, however, is incompletely understood. Using [18F]-DPA-714 positron emission tomography (PET) imaging targeting the translocator protein (TSPO), an immune cell marker, we sought to characterize the progression of EBOV-associated organ-level pathophysiology in the EBOV Rhesus macaque model. Dynamic [18F]-DPA-714 PET/computed tomography imaging was performed longitudinally at baseline and at multiple time points after EBOV inoculation, and distribution volumes (Vt) were calculated as a measure of peripheral TSPO binding. Using a mixed-effect linear regression model, spleen and lung Vt decreased, while the bone marrow Vt increased over time after infection. No clear trend was found for liver Vt. Multiple plasma cytokines correlated negatively with lung/spleen Vt and positively with bone marrow Vt. Multiplex immunofluorescence staining in spleen and lung sections confirmed organ-level lymphoid and monocytic loss/apoptosis, thus validating the imaging results. Our findings are consistent with EBOV-induced progressive monocytic and lymphocytic depletion in the spleen, rather than immune activation, as well as depletion of alveolar macrophages in the lungs, with inefficient reactive neutrophilic activation. Increased bone marrow Vt, on the other hand, suggests hematopoietic activation in response to systemic immune cell depletion and leukocytosis and could have prognostic relevance. In vivo PET imaging provided better understanding of organ-level pathophysiology during EBOV infection. A similar approach can be used to delineate the pathophysiology of other systemic infections and to evaluate the effectiveness of newly developed treatment and vaccine strategies.


Assuntos
Doença pelo Vírus Ebola , Tomografia por Emissão de Pósitrons , Receptores de GABA , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Doença pelo Vírus Ebola/diagnóstico por imagem , Doença pelo Vírus Ebola/patologia , Pulmão/patologia , Macaca mulatta , Tomografia por Emissão de Pósitrons/métodos , Pirazóis/metabolismo , Pirimidinas/metabolismo , Receptores de GABA/metabolismo , Baço/patologia
10.
Nano Lett ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619226

RESUMO

Halide perovskite-based resistive switching memory (memristor) has potential in an artificial synapse. However, an abrupt switch behavior observed for a formamidinium lead triiodide (FAPbI3)-based memristor is undesirable for an artificial synapse. Here, we report on the δ-FAPbI3/atomic-layer-deposited (ALD)-SnO2 bilayer memristor for gradual analogue resistive switching. In comparison to a single-layer δ-FAPbI3 memristor, the heterojunction δ-FAPbI3/ALD-SnO2 bilayer effectively reduces the current level in the high-resistance state. The analog resistive switching characteristics of δ-FAPbI3/ALD-SnO2 demonstrate exceptional linearity and potentiation/depression performance, resembling an artificial synapse for neuromorphic computing. The nonlinearity of long-term potentiation and long-term depression is notably decreased from 12.26 to 0.60 and from -8.79 to -3.47, respectively. Moreover, the δ-FAPbI3/ALD-SnO2 bilayer achieves a recognition rate of ≤94.04% based on the modified National Institute of Standards and Technology database (MNIST), establishing its potential in an efficient artificial synapse.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA