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1.
Nature ; 607(7919): 540-547, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35794482

RESUMEN

Gonadal development is a complex process that involves sex determination followed by divergent maturation into either testes or ovaries1. Historically, limited tissue accessibility, a lack of reliable in vitro models and critical differences between humans and mice have hampered our knowledge of human gonadogenesis, despite its importance in gonadal conditions and infertility. Here, we generated a comprehensive map of first- and second-trimester human gonads using a combination of single-cell and spatial transcriptomics, chromatin accessibility assays and fluorescent microscopy. We extracted human-specific regulatory programmes that control the development of germline and somatic cell lineages by profiling equivalent developmental stages in mice. In both species, we define the somatic cell states present at the time of sex specification, including the bipotent early supporting population that, in males, upregulates the testis-determining factor SRY and sPAX8s, a gonadal lineage located at the gonadal-mesonephric interface. In females, we resolve the cellular and molecular events that give rise to the first and second waves of granulosa cells that compartmentalize the developing ovary to modulate germ cell differentiation. In males, we identify human SIGLEC15+ and TREM2+ fetal testicular macrophages, which signal to somatic cells outside and inside the developing testis cords, respectively. This study provides a comprehensive spatiotemporal map of human and mouse gonadal differentiation, which can guide in vitro gonadogenesis.


Asunto(s)
Linaje de la Célula , Células Germinativas , Ovario , Diferenciación Sexual , Análisis de la Célula Individual , Testículo , Animales , Cromatina/genética , Cromatina/metabolismo , Femenino , Células Germinativas/citología , Células Germinativas/metabolismo , Células de la Granulosa/citología , Células de la Granulosa/metabolismo , Humanos , Inmunoglobulinas , Macrófagos/metabolismo , Masculino , Glicoproteínas de Membrana , Proteínas de la Membrana , Ratones , Microscopía Fluorescente , Ovario/citología , Ovario/embriología , Factor de Transcripción PAX8 , Embarazo , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Receptores Inmunológicos , Diferenciación Sexual/genética , Testículo/citología , Testículo/embriología , Transcriptoma
2.
Annu Rev Pharmacol Toxicol ; 63: 187-209, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35914767

RESUMEN

Synthetic cannabinoids (SCs) are a chemically diverse group of new psychoactive substances (NPSs) that target the endocannabinoid system, triggering a plethora of actions (e.g., elevated mood sensation, relaxation, appetite stimulation) that resemble, but are more intense than, those induced by cannabis. Although some of these effects have been explored for therapeutic applications, anticipated stronger psychoactive effects than cannabis and reduced risk perception have increased the recreational use of SCs, which have dominated the NPS market in the United States and Europe over the past decade. However, rising SC-related intoxications and deaths represent a major public health concern and embody a major challenge for policy makers. Here, we review the pharmacology and toxicology of SCs. A thorough characterization of SCs' pharmacodynamics and toxicodynamics is important to better understand the main mechanisms underlying acute and chronic effects of SCs, interpret the clinical/pathological findings related to SC use, and improve SC risk awareness.


Asunto(s)
Cannabinoides , Humanos , Cannabinoides/farmacología , Agonistas de Receptores de Cannabinoides/farmacología , Endocannabinoides
3.
Bioessays ; 46(1): e2300098, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38018264

RESUMEN

The evolution and biodiversity of ageing have long fascinated scientists and the public alike. While mammals, including long-lived species such as humans, show a marked ageing process, some species of reptiles and amphibians exhibit very slow and even the absence of ageing phenotypes. How can reptiles and other vertebrates age slower than mammals? Herein, I propose that evolving during the rule of the dinosaurs left a lasting legacy in mammals. For over 100 million years when dinosaurs were the dominant predators, mammals were generally small, nocturnal, and short-lived. My hypothesis is that such a long evolutionary pressure on early mammals for rapid reproduction led to the loss or inactivation of genes and pathways associated with long life. I call this the 'longevity bottleneck hypothesis', which is further supported by the absence in mammals of regenerative traits. Although mammals, such as humans, can evolve long lifespans, they do so under constraints dating to the dinosaur era.


Asunto(s)
Dinosaurios , Longevidad , Animales , Envejecimiento/fisiología , Dinosaurios/fisiología , Mamíferos/fisiología , Reptiles , Evolución Biológica
4.
Nucleic Acids Res ; 52(D1): D203-D212, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37811871

RESUMEN

With recent progress in mapping N7-methylguanosine (m7G) RNA methylation sites, tens of thousands of experimentally validated m7G sites have been discovered in various species, shedding light on the significant role of m7G modification in regulating numerous biological processes including disease pathogenesis. An integrated resource that enables the sharing, annotation and customized analysis of m7G data will greatly facilitate m7G studies under various physiological contexts. We previously developed the m7GHub database to host mRNA m7G sites identified in the human transcriptome. Here, we present m7GHub v.2.0, an updated resource for a comprehensive collection of m7G modifications in various types of RNA across multiple species: an m7GDB database containing 430 898 putative m7G sites identified in 23 species, collected from both widely applied next-generation sequencing (NGS) and the emerging Oxford Nanopore direct RNA sequencing (ONT) techniques; an m7GDiseaseDB hosting 156 206 m7G-associated variants (involving addition or removal of an m7G site), including 3238 disease-relevant m7G-SNPs that may function through epitranscriptome disturbance; and two enhanced analysis modules to perform interactive analyses on the collections of m7G sites (m7GFinder) and functional variants (m7GSNPer). We expect that m7Ghub v.2.0 should serve as a valuable centralized resource for studying m7G modification. It is freely accessible at: www.rnamd.org/m7GHub2.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , Secuenciación de Nucleótidos de Alto Rendimiento , Procesamiento Postranscripcional del ARN , Humanos , Interpretación Estadística de Datos , Guanosina/genética
5.
Nucleic Acids Res ; 52(D1): D900-D908, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37933854

RESUMEN

Ageing is a complex and multifactorial process. For two decades, the Human Ageing Genomic Resources (HAGR) have aided researchers in the study of various aspects of ageing and its manipulation. Here, we present the key features and recent enhancements of these resources, focusing on its six main databases. One database, GenAge, focuses on genes related to ageing, featuring 307 genes linked to human ageing and 2205 genes associated with longevity and ageing in model organisms. AnAge focuses on ageing, longevity, and life-history across animal species, containing data on 4645 species. DrugAge includes information about 1097 longevity drugs and compounds in model organisms such as mice, rats, flies, worms and yeast. GenDR provides a list of 214 genes associated with the life-extending benefits of dietary restriction in model organisms. CellAge contains a catalogue of 866 genes associated with cellular senescence. The LongevityMap serves as a repository for genetic variants associated with human longevity, encompassing 3144 variants pertaining to 884 genes. Additionally, HAGR provides various tools as well as gene expression signatures of ageing, dietary restriction, and replicative senescence based on meta-analyses. Our databases are integrated, regularly updated, and manually curated by experts. HAGR is freely available online (https://genomics.senescence.info/).


Asunto(s)
Envejecimiento , Bases de Datos Genéticas , Genómica , Animales , Humanos , Envejecimiento/genética , Senescencia Celular , Longevidad/genética
6.
Semin Cell Dev Biol ; 133: 32-41, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-35697594

RESUMEN

Extracellular vesicles (EVs) are membrane-delimited vesicular bodies carrying different molecules, classified according to their size, density, cargo, and origin. Research on this topic has been actively growing through the years, as EVs are associated with critical pathological processes such as neurodegenerative diseases and cancer. Despite that, studies exploring the physiological functions of EVs are sparse, with particular emphasis on their role in organismal development, initial cell differentiation, and morphogenesis. In this review, we explore the topic of EVs from a developmental perspective, discussing their role in the earliest cell-fate decisions and neural tissue morphogenesis. We focus on the function of EVs through development to highlight possible conserved or novel processes that can impact disease progression. Specifically, we take advantage of what was learned about their role in development so far to discuss EVs impact on glioblastoma, a particular brain tumor of stem-cell origin and poor prognosis, and how their function can be hijacked to improve current therapies.


Asunto(s)
Vesículas Extracelulares , Glioblastoma , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Vesículas Extracelulares/patología , Comunicación Celular , Células Madre , Diferenciación Celular
7.
Trends Genet ; 38(3): 216-217, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34756472

RESUMEN

A PubMed analysis shows that the vast majority of human genes have been studied in the context of cancer. As such, the study of nearly any human gene can be justified based on existing literature by its potential relevance to cancer. Moreover, these results have implications for analyzing and interpreting large-scale analyses.


Asunto(s)
Neoplasias , Humanos , Neoplasias/genética
8.
Mol Psychiatry ; 29(7): 2261-2273, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38366114

RESUMEN

Glutamatergic neurotransmission system dysregulation may play an important role in the pathophysiology of Alzheimer's disease (AD). However, reported results on glutamatergic components across brain regions are contradictory. Here, we conducted a systematic review with meta-analysis to examine whether there are consistent glutamatergic abnormalities in the human AD brain. We searched PubMed and Web of Science (database origin-October 2023) reports evaluating glutamate, glutamine, glutaminase, glutamine synthetase, glutamate reuptake, aspartate, excitatory amino acid transporters, vesicular glutamate transporters, glycine, D-serine, metabotropic and ionotropic glutamate receptors in the AD human brain (PROSPERO #CDRD42022299518). The studies were synthesized by outcome and brain region. We included cortical regions, the whole brain (cortical and subcortical regions combined), the entorhinal cortex and the hippocampus. Pooled effect sizes were determined with standardized mean differences (SMD), random effects adjusted by false discovery rate, and heterogeneity was examined by I2 statistics. The search retrieved 6 936 articles, 63 meeting the inclusion criteria (N = 709CN/786AD; mean age 75/79). We showed that the brain of AD individuals presents decreased glutamate (SMD = -0.82; I2 = 74.54%; P < 0.001) and aspartate levels (SMD = -0.64; I2 = 89.71%; P = 0.006), and reuptake (SMD = -0.75; I2 = 83.04%; P < 0.001. We also found reduced α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPAR)-GluA2/3 levels (SMD = -0.63; I2 = 95.55%; P = 0.046), hypofunctional N-methyl-D-aspartate receptor (NMDAR) (SMD = -0.60; I2 = 91.47%; P < 0.001) and selective reduction of NMDAR-GluN2B subunit levels (SMD = -1.07; I2 = 41.81%; P < 0.001). Regional differences include lower glutamate levels in cortical areas and aspartate levels in cortical areas and in the hippocampus, reduced glutamate reuptake, reduced AMPAR-GluA2/3 in the entorhinal cortex, hypofunction of NMDAR in cortical areas, and a decrease in NMDAR-GluN2B subunit levels in the entorhinal cortex and hippocampus. Other parameters studied were not altered. Our findings show depletion of the glutamatergic system and emphasize the importance of understanding glutamate-mediated neurotoxicity in AD. This study has implications for the development of therapies and biomarkers in AD.


Asunto(s)
Enfermedad de Alzheimer , Encéfalo , Ácido Glutámico , Enfermedad de Alzheimer/metabolismo , Humanos , Ácido Glutámico/metabolismo , Encéfalo/metabolismo , Hipocampo/metabolismo , Transmisión Sináptica/fisiología , Glutamina/metabolismo
9.
Immunity ; 45(6): 1219-1231, 2016 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-27913094

RESUMEN

Hematopoietic stem cells (HSCs) self-renew in bone marrow niches formed by mesenchymal progenitors and endothelial cells expressing the chemokine CXCL12, but whether a separate niche instructs multipotent progenitor (MPP) differentiation remains unclear. We show that MPPs resided in HSC niches, where they encountered lineage-instructive differentiation signals. Conditional deletion of the chemokine receptor CXCR4 in MPPs reduced differentiation into common lymphoid progenitors (CLPs), which decreased lymphopoiesis. CXCR4 was required for CLP positioning near Interleukin-7+ (IL-7) cells and for optimal IL-7 receptor signaling. IL-7+ cells expressed CXCL12 and the cytokine SCF, were mesenchymal progenitors capable of differentiation into osteoblasts and adipocytes, and comprised a minor subset of sinusoidal endothelial cells. Conditional Il7 deletion in mesenchymal progenitors reduced B-lineage committed CLPs, while conditional Cxcl12 or Scf deletion from IL-7+ cells reduced HSC and MPP numbers. Thus, HSC maintenance and multilineage differentiation are distinct cell lineage decisions that are both controlled by HSC niches.


Asunto(s)
Diferenciación Celular/fisiología , Células Madre Hematopoyéticas/citología , Células Madre Multipotentes/citología , Nicho de Células Madre/fisiología , Animales , Linaje de la Célula/fisiología , Separación Celular , Quimiocina CXCL2/metabolismo , Citometría de Flujo , Interleucina-7/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos
10.
Nucleic Acids Res ; 51(D1): D145-D158, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36454018

RESUMEN

Gene co-expression analysis has emerged as a powerful method to provide insights into gene function and regulation. The rapid growth of publicly available RNA-sequencing (RNA-seq) data has created opportunities for researchers to employ this abundant data to help decipher the complexity and biology of genomes. Co-expression networks have proven effective for inferring the relationship between the genes, for gene prioritization and for assigning function to poorly annotated genes based on their co-expressed partners. To facilitate such analyses we created previously an online co-expression tool for humans and mice entitled GeneFriends. To continue providing a valuable tool to the scientific community, we have now updated the GeneFriends database and website. Here, we present the new version of GeneFriends, which includes gene and transcript co-expression networks based on RNA-seq data from 46 475 human and 34 322 mouse samples. The new database also encompasses tissue-specific gene co-expression networks for 20 human and 21 mouse tissues, dataset-specific gene co-expression maps based on TCGA and GTEx projects and gene co-expression networks for additional seven model organisms (fruit fly, zebrafish, worm, rat, yeast, cow and chicken). GeneFriends is freely available at http://www.genefriends.org/.


Asunto(s)
Bases de Datos Genéticas , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Animales , Humanos , ARN , Análisis de Secuencia de ARN
11.
Nucleic Acids Res ; 51(D1): D106-D116, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36382409

RESUMEN

With advanced technologies to map RNA modifications, our understanding of them has been revolutionized, and they are seen to be far more widespread and important than previously thought. Current next-generation sequencing (NGS)-based modification profiling methods are blind to RNA modifications and thus require selective chemical treatment or antibody immunoprecipitation methods for particular modification types. They also face the problem of short read length, isoform ambiguities, biases and artifacts. Direct RNA sequencing (DRS) technologies, commercialized by Oxford Nanopore Technologies (ONT), enable the direct interrogation of any given modification present in individual transcripts and promise to address the limitations of previous NGS-based methods. Here, we present the first ONT-based database of quantitative RNA modification profiles, DirectRMDB, which includes 16 types of modification and a total of 904,712 modification sites in 25 species identified from 39 independent studies. In addition to standard functions adopted by existing databases, such as gene annotations and post-transcriptional association analysis, we provide a fresh view of RNA modifications, which enables exploration of the epitranscriptome in an isoform-specific manner. The DirectRMDB database is freely available at: http://www.rnamd.org/directRMDB/.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Procesamiento Postranscripcional del ARN , Análisis de Secuencia de ARN , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Anotación de Secuencia Molecular , Isoformas de Proteínas , ARN/genética , Análisis de Secuencia de ARN/métodos , Bases de Datos de Ácidos Nucleicos
12.
Nucleic Acids Res ; 51(D1): D1388-D1396, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36062570

RESUMEN

Recent advances in epitranscriptomics have unveiled functional associations between RNA modifications (RMs) and multiple human diseases, but distinguishing the functional or disease-related single nucleotide variants (SNVs) from the majority of 'silent' variants remains a major challenge. We previously developed the RMDisease database for unveiling the association between genetic variants and RMs concerning human disease pathogenesis. In this work, we present RMDisease v2.0, an updated database with expanded coverage. Using deep learning models and from 873 819 experimentally validated RM sites, we identified a total of 1 366 252 RM-associated variants that may affect (add or remove an RM site) 16 different types of RNA modifications (m6A, m5C, m1A, m5U, Ψ, m6Am, m7G, A-to-I, ac4C, Am, Cm, Um, Gm, hm5C, D and f5C) in 20 organisms (human, mouse, rat, zebrafish, maize, fruit fly, yeast, fission yeast, Arabidopsis, rice, chicken, goat, sheep, pig, cow, rhesus monkey, tomato, chimpanzee, green monkey and SARS-CoV-2). Among them, 14 749 disease- and 2441 trait-associated genetic variants may function via the perturbation of epitranscriptomic markers. RMDisease v2.0 should serve as a useful resource for studying the genetic drivers of phenotypes that lie within the epitranscriptome layer circuitry, and is freely accessible at: www.rnamd.org/rmdisease2.


Asunto(s)
Bases de Datos Factuales , Procesamiento Postranscripcional del ARN , Animales , Humanos , Fenotipo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Epigenómica
13.
Eur Heart J ; 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39405050

RESUMEN

The win ratio method for analysing a composite clinical hierarchy of outcomes is growing in popularity especially in cardiovascular trials. This article gives a perspective on its use so far and the issues derived from that experience. Specifically, it focuses on the limitations of a conventional composite outcome; how does the win ratio work, what does it mean, and how to display its findings; guidance on choosing an appropriate clinical hierarchy of outcomes including clinical events, quantitative outcomes, and other options; the additional value of the win difference as a measure of absolute benefit: extension to stratified win ratio, subgroup analysis, matched win ratio, and covariate adjustment; determining trial size for a win ratio outcome; specific insights such as adaptive designs, use of repeat events, and use of margins and time averages for quantitative outcomes; a critique of potential misuses; availability of statistical software; and a statistical appendix on the methodological details. Throughout, each principle is illustrated by examples from specific cardiology trials. The article concludes with a set of recommendations for future use of the win ratio.

14.
J Physiol ; 602(19): 4865-4887, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39277824

RESUMEN

In mammals, the central circadian oscillator is located in the suprachiasmatic nucleus (SCN). Hypothalamus-pituitary-thyroid axis components exhibit circadian oscillation, regulated by both central clock innervation and intrinsic circadian clocks in the anterior pituitary and thyroid glands. Thyroid disorders alter the rhythmicity of peripheral clocks in a tissue-dependent response; however, whether these effects are influenced by alterations in the master clock remains unknown. This study aimed to characterize the effects of hypothyroidism on the rhythmicity of SCN, body temperature (BT) and metabolism, and the possible mechanisms involved in this signalling. C57BL/6J adult male mice were divided into Control and Hypothyroid groups. Profiles of spontaneous locomotor activity (SLA), BT, oxygen consumption ( V ̇ O 2 ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ ) and respiratory quotient (RQ) were determined under free-running conditions. Clock gene expression, and neuronal activity of the SCN and medial preoptic nucleus (MPOM) area were investigated in light-dark (LD) conditions. Triiodothyronine (T3) transcriptional regulation of Bmal1 promoter activity was evaluated in GH3-transfected cells. Hypothyroidism delayed the rhythmicity of SLA and BT, and altered the expression of core clock components in the SCN. The activity of SCN neurons and their outputs were also affected, as evidenced by the loss of circadian rhythmicity in V ̇ O 2 ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ and RQ and alterations in the neuronal activity pattern of MPOM. In GH3 cells, T3 increased Bmal1 promoter activity in a time-dependent manner. Thyroid hormone may act as a temporal cue for the central circadian clock, and the uncoupling of central and peripheral clocks might contribute to a wide range of metabolic and thermoregulatory impairments observed in hypothyroidism. KEY POINTS: Hypothyroidism alters clock gene expression in the suprachiasmatic nucleus (SCN). Thyroid hypofunction alters the phase of spontaneous locomotor activity and body temperature rhythms. Thyroid hormone deficiency alters the daily pattern of SCN and medial preoptic nucleus neuronal activities. Hypothyroidism alterations are extended to daily oscillations of oxygen consumption and metabolism, which might contribute to the development of metabolic syndrome. Triiodothyronine increases Bmal1 promoter activity acting as temporal cue for the central circadian clock.


Asunto(s)
Factores de Transcripción ARNTL , Hipotiroidismo , Ratones Endogámicos C57BL , Núcleo Supraquiasmático , Triyodotironina , Animales , Masculino , Hipotiroidismo/fisiopatología , Hipotiroidismo/metabolismo , Hipotiroidismo/genética , Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Ratones , Núcleo Supraquiasmático/metabolismo , Núcleo Supraquiasmático/fisiología , Ritmo Circadiano/fisiología , Temperatura Corporal/fisiología , Relojes Circadianos/genética , Relojes Circadianos/fisiología , Regulación de la Expresión Génica
15.
Circulation ; 148(13): 1011-1022, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37621153

RESUMEN

BACKGROUND: It is not known whether the benefits of sodium-glucose cotransporter 2 inhibitors in heart failure persist after years of therapy. METHODS: In the EMPEROR-Reduced (Empagliflozin Outcome Trials in Chronic Heart Failure With Reduced Ejection Fraction) and EMPEROR-Preserved (Empagliflozin Outcome Trials in Chronic Heart Failure With Preserved Ejection Fraction) trials, patients with heart failure were randomly assigned (double-blind) to placebo or empagliflozin 10 mg/day for a median of 16 and 26 months, respectively. At the end of the trials, 6799 patients (placebo 3381, empagliflozin 3418) were prospectively withdrawn from treatment in a blinded manner, and, of these, 3981 patients (placebo 2020, empagliflozin 1961) underwent prespecified in-person assessments after ≈30 days off treatment. RESULTS: From 90 days from the start of closeout to the end of double-blind treatment, the annualized risk of cardiovascular death or hospitalization for heart failure was lower in empagliflozin-treated patients than in placebo-treated patients (10.7 [95% CI, 9.0-12.6] versus 13.5 [95% CI, 11.5-15.6] events per 100 patient-years, respectively; hazard ratio 0.76 [95% CI, 0.60-0.96]). When the study drugs were withdrawn for ≈30 days, the annualized risk of cardiovascular death or hospitalization for heart failure increased in patients withdrawn from empagliflozin but not in those withdrawn from placebo (17.0 [95% CI, 12.6-22.1] versus 14.1 [95% CI, 10.1-18.8] events per 100 patient-years for empagliflozin and placebo, respectively). The hazard ratio for the change in risk in the patients withdrawn from empagliflozin was 1.75 (95% CI, 1.20-2.54), P=0.0034, whereas the change in the risk in patients withdrawn from placebo was not significant (hazard ratio 1.12 [95% CI, 0.76-1.66]); time period-by-treatment interaction, P=0.068. After withdrawal, the Kansas City Cardiomyopathy Questionnaire Clinical Summary Score declined by 1.6±0.4 in patients withdrawn from empagliflozin versus placebo (P<0.0001). Furthermore, withdrawal of empagliflozin was accompanied by increases in fasting glucose, body weight, systolic blood pressure, estimated glomerular filtration rate, N-terminal pro-hormone B-type natriuretic peptide, uric acid, and serum bicarbonate and decreases in hemoglobin and hematocrit (all P<0.01). These physiological and laboratory changes were the inverse of the effects of the drug seen at the start of the trials during the initiation of treatment (≈1-3 years earlier) in the same cohort of patients. CONCLUSIONS: These observations demonstrate a persistent effect of empagliflozin in patients with heart failure even after years of treatment, which dissipated rapidly after withdrawal of the drug. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifiers: NCT03057977 and NCT03057951.


Asunto(s)
Compuestos de Bencidrilo , Insuficiencia Cardíaca , Humanos , Compuestos de Bencidrilo/uso terapéutico , Método Doble Ciego , Insuficiencia Cardíaca/tratamiento farmacológico , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Resultado del Tratamiento
16.
Stroke ; 55(1): 78-88, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134260

RESUMEN

BACKGROUND: The association of COVID-19 with higher bleeding risk and worse outcomes in acute ischemic stroke (AIS) undergoing revascularization may be related to the presence of infection symptoms. We aimed to assess the safety and outcomes of revascularization treatments in patients with AIS with asymptomatic COVID-19 (AS-COVID) or symptomatic COVID-19 (S-COVID). METHODS: We conducted an international multicenter retrospective cohort study of consecutive AIS tested for SARS-CoV-2, receiving intravenous thrombolysis and endovascular treatment between 2020 and 2021. We compared COVID-negative controls, AS-COVID, and S-COVID using multivariable regression. We assessed symptomatic intracranial hemorrhage (symptomatic intracerebral hemorrhage), mortality, and 3-month disability (modified Rankin Scale score). RESULTS: Among 15 124 patients from 105 centers (median age, 71 years; 49% men; 39% treated with intravenous thrombolysis only; and 61% with endovascular treatment±intravenous thrombolysis), 849 (5.6%) had COVID-19, of whom 395 (46%) were asymptomatic and 454 (54%) symptomatic. Compared with controls, both patients with AS-COVID and S-COVID had higher symptomatic intracerebral hemorrhage rates (COVID-controls, 5%; AS-COVID, 7.6%; S-COVID, 9.4%; adjusted odds ratio [aOR], 1.43 [95% CI, 1.03-1.99]; aOR, 1.63 [95% CI, 1.14-2.32], respectively). Only in patients with symptomatic infections, we observed a significant increase in mortality at 24 hours (COVID-controls, 1.3%; S-COVID, 4.8%; aOR, 2.97 [95% CI, 1.76-5.03]) and 3 months (COVID-controls, 19.5%; S-COVID, 40%; aOR, 2.64 [95% CI, 2.06-3.37]). Patients with COVID-19 had worse 3-month disability regardless of disease symptoms although disability was affected to a greater extent in symptomatic patients (aOR for worse modified Rankin Scale score shift: AS-COVID, 1.25 [95% CI, 1.03-1.51]; S-COVID, 2.10 [95% CI, 1.75-2.53]). S-COVID had lower successful recanalization (74.9% versus 85.6%; P<0.001), first pass recanalization (20.3% versus 28.3%; P=0.005), and a higher number of passes. CONCLUSIONS: In AIS undergoing revascularization treatments, both AS-COVID and S-COVID influence the risk of intracranial bleeding and worse clinical outcomes. The magnitude of this effect is more pronounced in symptomatic infections, which also present less favorable recanalization outcomes. These findings emphasize the impact of SARS-CoV-2 infection on the prognosis of revascularized AIS independent of symptom status. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04895462.


Asunto(s)
Isquemia Encefálica , COVID-19 , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Masculino , Humanos , Anciano , Femenino , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/cirugía , Isquemia Encefálica/epidemiología , Isquemia Encefálica/cirugía , Terapia Trombolítica , Estudios Retrospectivos , Resultado del Tratamiento , COVID-19/complicaciones , COVID-19/terapia , SARS-CoV-2 , Hemorragia Cerebral/complicaciones , Hemorragias Intracraneales/complicaciones , Trombectomía
17.
Stroke ; 55(9): 2353-2358, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39051090

RESUMEN

BACKGROUND: Large vessel occlusion acute ischemic stroke prognosis improved following the 2015 endovascular therapy (EVT) trials. Blood-based biomarkers may improve outcome prediction. We aimed to assess plasma brain-derived tau (BD-Tau) performance in predicting post-EVT large vessel occlusion acute ischemic stroke outcomes. METHODS: We included 2 temporally independent prospective cohorts of anterior circulation in patients with large vessel occlusion acute ischemic stroke who successfully recanalized post-EVT. We measured plasma BD-Tau, GFAP (glial-fibrillary-acidic-protein), NfL (neurofilament-light-chain), and total-Tau upon admission, immediately, 24 hours, and 72 hours post-EVT. Twenty-four-hour neuroimaging and 90-day functional outcomes were independently assessed using the Alberta Stroke Program Early Computed Tomography Score (good outcome: >7 or unchanged) and the modified Rankin Scale (favorable outcome <3 or unchanged), respectively. Based on the first cohort (derivation), we built a multivariable logistic regression model to predict a 90-day functional outcome. Model results were evaluated using the second cohort (evaluation). RESULTS: In the derivation cohort (n=78, mean age=72.9 years, 50% women), 62% of patients had a good 24-hour neuroimaging outcome, and 45% had a favorable 90-day functional outcome. GFAP admission-to-EVT rate-of-change was the best predictor for early neuroimaging outcome but not for 90-day functional outcome. At admission, BD-Tau levels presented the highest discriminative performance for 90-day functional outcomes (area under the curve, 0.76 [95% CI, 0.65-0.87]; P<0.001). The model incorporating age, admission BD-Tau, and 24-hour Alberta Stroke Program Early Computed Tomography Score achieved excellent discrimination of 90-day functional outcome (area under the curve, 0.89 [95% CI, 0.82-0.97]; P<0.001). The score's predictive performance was maintained in the evaluation cohort (n=66; area under the curve, 0.82 [95% CI, 0.71-0.92]; P<0.001). CONCLUSIONS: Admission plasma BD-Tau accurately predicted 90-day functional outcomes in patients with large vessel occlusion acute ischemic stroke after successful EVT. The proposed model may predict functional outcomes using objective measures, minimizing human-related biases and serving as a simplified prognostic tool for AIS.


Asunto(s)
Biomarcadores , Accidente Cerebrovascular Isquémico , Proteínas tau , Humanos , Femenino , Masculino , Anciano , Proteínas tau/sangre , Pronóstico , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/sangre , Accidente Cerebrovascular Isquémico/terapia , Persona de Mediana Edad , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios Prospectivos , Procedimientos Endovasculares/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/sangre , Isquemia Encefálica/terapia , Estudios de Cohortes , Proteína Ácida Fibrilar de la Glía/sangre
18.
Stroke ; 55(7): 1767-1775, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38748598

RESUMEN

BACKGROUND: Studies comparing bridging intravenous thrombolysis (IVT) with direct endovascular therapy (EVT) in patients with acute ischemic stroke who present late are limited. We aimed to compare the clinical outcomes and safety of bridging IVT in patients with acute ischemic stroke due to anterior circulation large vessel occlusion who underwent EVT 6 to 24 hours after time last known well. METHODS: We enrolled patients with anterior circulation large vessel occlusion stroke and a National Institutes of Health Stroke Scale score of ≥6 from 20 centers across 10 countries in the multicenter retrospective CLEAR study (CT for Late Endovascular Reperfusion) between January 2014 and May 2022. We used inverse probability of treatment weighting modeling adjusted for clinical and imaging confounders to compare functional outcomes, reperfusion success, symptomatic intracranial hemorrhage, and mortality between EVT patients with and without prior IVT. RESULTS: Of 5098 patients screened for eligibility, we included 2749 patients, of whom 549 received bridging IVT before EVT. The timing of IVT was not recorded. Witnessed stroke onset and transfer rates were higher in the bridging IVT group (25% versus 12% and 77% versus 55%, respectively, P value for both <0.0001), and time intervals between stroke onset and treatment were shorter (time last known well-start of EVT median 560 minutes [interquartile range, 432-791] versus 724 minutes [interquartile range, 544-912]; P<0.0001). After adjustment for confounders, there was no difference in functional outcome at 3 months (adjusted common odds ratio for modified Rankin Scale shift, 1.03 [95% CI, 0.89-1.19]; P=0.72) or successful reperfusion (adjusted odds ratio, 1.19 [95% CI, 0.81-1.75]; P=0.39). There were no safety concerns associated with bridging IVT versus direct EVT (symptomatic intracranial hemorrhage: adjusted odds ratio, 0.75 [95% CI, 0.38-1.48]; P=0.40; mortality: adjusted odds ratio, 1.14 [95% CI, 0.89-1.46]; P=0.31). Results were unchanged when the analysis was limited to patients who received IVT >6 hours after last known well. CONCLUSIONS: In patients with an anterior circulation large vessel occlusion stroke who underwent EVT 6 to 24 hours from last known well, bridging IVT was not associated with a difference in outcomes compared with direct EVT. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04096248.


Asunto(s)
Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Terapia Trombolítica , Humanos , Masculino , Femenino , Anciano , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/cirugía , Procedimientos Endovasculares/métodos , Persona de Mediana Edad , Terapia Trombolítica/métodos , Resultado del Tratamiento , Estudios Retrospectivos , Anciano de 80 o más Años , Fibrinolíticos/uso terapéutico , Fibrinolíticos/administración & dosificación , Tiempo de Tratamiento , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/terapia
19.
Stroke ; 55(2): 278-287, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38252759

RESUMEN

BACKGROUND: The association between sex and outcome after endovascular thrombectomy of acute ischemic stroke is unclear. The aim of this study was to compare the clinical and safety outcomes between men and women treated with endovascular thrombectomy in the late 6-to-24-hour window period. METHODS: This multicenter, retrospective observational cohort study included consecutive patients who underwent endovascular thrombectomy of anterior circulation stroke in the late window from 66 clinical sites in 10 countries from January 2014 to May 2022. The primary outcome was the 90-day ordinal modified Rankin Scale score. Secondary outcomes included 90-day functional independence (FI), return of Rankin (RoR) to prestroke baseline, FI or RoR, symptomatic intracranial hemorrhage, and mortality. Multivariable and inverse probability of treatment weighting methods were used. We explored the interaction of sex with baseline characteristics on the outcomes ordinal modified Rankin Scale and FI or RoR. RESULTS: Of 1932 patients, 1055 were women and 877 were men. Women were older (77 versus 69 years), had higher rates of atrial fibrillation, hypertension, and greater prestroke disability, but there was no difference in baseline National Institutes of Health Stroke Scale score. Inverse probability of treatment weighting analysis showed no difference between women and men in ordinal modified Rankin Scale (odds ratio, 0.98 [95% CI, 0.79-1.21]), FI or RoR (odds ratio, 0.98 [95% CI, 0.78-1.22]), severe disability or mortality (odds ratio, 0.99 [95% CI, 0.80-1.23]). The multivariable analysis of the above end points was concordant. There were no interactions between baseline characteristics and sex on the outcomes of ordinal modified Rankin Scale and FI or RoR. CONCLUSIONS: In late presenting patients with anterior circulation stroke treated with endovascular thrombectomy in the 6 to 24-hour window, there was no difference in clinical or safety outcomes between men and women.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Estados Unidos , Humanos , Femenino , Masculino , Caracteres Sexuales , Estudios Retrospectivos , Accidente Cerebrovascular/cirugía
20.
J Am Chem Soc ; 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39374484

RESUMEN

For many chemical reactions, it remains notoriously difficult to predict and experimentally determine the rates and branching ratios between different reaction channels. This is particularly the case for reactions involving short-lived intermediates, whose observation requires ultrafast methods. The UV photochemistry of bromoform (CHBr3) is among the most intensely studied photoreactions. Yet, a detailed understanding of the chemical pathways leading to the production of atomic Br and molecular Br2 fragments has proven challenging. In particular, the role of isomerization and/or roaming and their competition with direct C-Br bond scission has been a matter of continued debate. Here, gas-phase ultrafast megaelectronvolt electron diffraction (MeV-UED) is used to directly study structural dynamics in bromoform after single 267 nm photon excitation with femtosecond temporal resolution. The results show unambiguously that isomerization contributes significantly to the early stages of the UV photochemistry of bromoform. In addition to direct C-Br bond breaking within <200 fs, formation of iso-CHBr3 (Br-CH-Br-Br) is observed on the same time scale and with an isomer lifetime of >1.1 ps. The branching ratio between direct dissociation and isomerization is determined to be 0.4 ± 0.2:0.6 ± 0.2, i.e., approximately 60% of molecules undergo isomerization within the first few hundred femtoseconds after UV excitation. The structure and time of formation of iso-CHBr3 compare favorably with the results of an ab initio molecular dynamics simulation. The lifetime and interatomic distances of the isomer are consistent with the involvement of a roaming reaction mechanism.

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