Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 376
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Cell ; 186(11): 2380-2391.e9, 2023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37146611

RESUMEN

Prime-boost regimens for COVID-19 vaccines elicit poor antibody responses against Omicron-based variants and employ frequent boosters to maintain antibody levels. We present a natural infection-mimicking technology that combines features of mRNA- and protein nanoparticle-based vaccines through encoding self-assembling enveloped virus-like particles (eVLPs). eVLP assembly is achieved by inserting an ESCRT- and ALIX-binding region (EABR) into the SARS-CoV-2 spike cytoplasmic tail, which recruits ESCRT proteins to induce eVLP budding from cells. Purified spike-EABR eVLPs presented densely arrayed spikes and elicited potent antibody responses in mice. Two immunizations with mRNA-LNP encoding spike-EABR elicited potent CD8+ T cell responses and superior neutralizing antibody responses against original and variant SARS-CoV-2 compared with conventional spike-encoding mRNA-LNP and purified spike-EABR eVLPs, improving neutralizing titers >10-fold against Omicron-based variants for 3 months post-boost. Thus, EABR technology enhances potency and breadth of vaccine-induced responses through antigen presentation on cell surfaces and eVLPs, enabling longer-lasting protection against SARS-CoV-2 and other viruses.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Vacunas de ARNm , Animales , Humanos , Ratones , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Complejos de Clasificación Endosomal Requeridos para el Transporte , ARN Mensajero , SARS-CoV-2
2.
Cell ; 184(12): 3205-3221.e24, 2021 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-34015271

RESUMEN

Monoclonal antibodies (mAbs) are a focus in vaccine and therapeutic design to counteract severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants. Here, we combined B cell sorting with single-cell VDJ and RNA sequencing (RNA-seq) and mAb structures to characterize B cell responses against SARS-CoV-2. We show that the SARS-CoV-2-specific B cell repertoire consists of transcriptionally distinct B cell populations with cells producing potently neutralizing antibodies (nAbs) localized in two clusters that resemble memory and activated B cells. Cryo-electron microscopy structures of selected nAbs from these two clusters complexed with SARS-CoV-2 spike trimers show recognition of various receptor-binding domain (RBD) epitopes. One of these mAbs, BG10-19, locks the spike trimer in a closed conformation to potently neutralize SARS-CoV-2, the recently arising mutants B.1.1.7 and B.1.351, and SARS-CoV and cross-reacts with heterologous RBDs. Together, our results characterize transcriptional differences among SARS-CoV-2-specific B cells and uncover cross-neutralizing Ab targets that will inform immunogen and therapeutic design against coronaviruses.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Linfocitos B/metabolismo , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/química , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/química , Anticuerpos Antivirales/inmunología , Complejo Antígeno-Anticuerpo/química , Complejo Antígeno-Anticuerpo/metabolismo , Reacciones Antígeno-Anticuerpo , Linfocitos B/citología , Linfocitos B/virología , COVID-19/patología , COVID-19/virología , Microscopía por Crioelectrón , Cristalografía por Rayos X , Perfilación de la Expresión Génica , Humanos , Inmunoglobulina A/inmunología , Región Variable de Inmunoglobulina/química , Región Variable de Inmunoglobulina/genética , Dominios Proteicos/inmunología , Multimerización de Proteína , Estructura Cuaternaria de Proteína , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/metabolismo , Análisis de Secuencia de ARN , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo
3.
Immunity ; 55(12): 2419-2435.e10, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36370711

RESUMEN

Increased immune evasion by SARS-CoV-2 variants of concern highlights the need for new therapeutic neutralizing antibodies. Immunization with nanoparticles co-displaying spike receptor-binding domains (RBDs) from eight sarbecoviruses (mosaic-8 RBD-nanoparticles) efficiently elicits cross-reactive polyclonal antibodies against conserved sarbecovirus RBD epitopes. Here, we identified monoclonal antibodies (mAbs) capable of cross-reactive binding and neutralization of animal sarbecoviruses and SARS-CoV-2 variants by screening single mouse B cells secreting IgGs that bind two or more sarbecovirus RBDs. Single-particle cryo-EM structures of antibody-spike complexes, including a Fab-Omicron complex, mapped neutralizing mAbs to conserved class 1/4 RBD epitopes. Structural analyses revealed neutralization mechanisms, potentials for intra-spike trimer cross-linking by IgGs, and induced changes in trimer upon Fab binding. In addition, we identified a mAb-resembling Bebtelovimab, an EUA-approved human class 3 anti-RBD mAb. These results support using mosaic RBD-nanoparticle vaccination to generate and identify therapeutic pan-sarbecovirus and pan-variant mAbs.


Asunto(s)
COVID-19 , Nanopartículas , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Ratones , Animales , Humanos , SARS-CoV-2 , Epítopos , Glicoproteína de la Espiga del Coronavirus , Anticuerpos Monoclonales , Pruebas de Neutralización , Anticuerpos Antivirales , Anticuerpos Neutralizantes
4.
Nature ; 621(7978): 289-294, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37704764

RESUMEN

Reaction rates at spatially heterogeneous, unstable interfaces are notoriously difficult to quantify, yet are essential in engineering many chemical systems, such as batteries1 and electrocatalysts2. Experimental characterizations of such materials by operando microscopy produce rich image datasets3-6, but data-driven methods to learn physics from these images are still lacking because of the complex coupling of reaction kinetics, surface chemistry and phase separation7. Here we show that heterogeneous reaction kinetics can be learned from in situ scanning transmission X-ray microscopy (STXM) images of carbon-coated lithium iron phosphate (LFP) nanoparticles. Combining a large dataset of STXM images with a thermodynamically consistent electrochemical phase-field model, partial differential equation (PDE)-constrained optimization and uncertainty quantification, we extract the free-energy landscape and reaction kinetics and verify their consistency with theoretical models. We also simultaneously learn the spatial heterogeneity of the reaction rate, which closely matches the carbon-coating thickness profiles obtained through Auger electron microscopy (AEM). Across 180,000 image pixels, the mean discrepancy with the learned model is remarkably small (<7%) and comparable with experimental noise. Our results open the possibility of learning nonequilibrium material properties beyond the reach of traditional experimental methods and offer a new non-destructive technique for characterizing and optimizing heterogeneous reactive surfaces.

5.
N Engl J Med ; 390(19): 1745-1755, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38749032

RESUMEN

BACKGROUND: Patients with acute intracerebral hemorrhage who are receiving factor Xa inhibitors have a risk of hematoma expansion. The effect of andexanet alfa, an agent that reverses the effects of factor Xa inhibitors, on hematoma volume expansion has not been well studied. METHODS: We randomly assigned, in a 1:1 ratio, patients who had taken factor Xa inhibitors within 15 hours before having an acute intracerebral hemorrhage to receive andexanet or usual care. The primary end point was hemostatic efficacy, defined by expansion of the hematoma volume by 35% or less at 12 hours after baseline, an increase in the score on the National Institutes of Health Stroke Scale of less than 7 points (scores range from 0 to 42, with higher scores indicating worse neurologic deficit) at 12 hours, and no receipt of rescue therapy between 3 hours and 12 hours. Safety end points were thrombotic events and death. RESULTS: A total of 263 patients were assigned to receive andexanet, and 267 to receive usual care. Efficacy was assessed in an interim analysis that included 452 patients, and safety was analyzed in all 530 enrolled patients. Atrial fibrillation was the most common indication for factor Xa inhibitors. Of the patients receiving usual care, 85.5% received prothrombin complex concentrate. Hemostatic efficacy was achieved in 150 of 224 patients (67.0%) receiving andexanet and in 121 of 228 (53.1%) receiving usual care (adjusted difference, 13.4 percentage points; 95% confidence interval [CI], 4.6 to 22.2; P = 0.003). The median reduction from baseline to the 1-to-2-hour nadir in anti-factor Xa activity was 94.5% with andexanet and 26.9% with usual care (P<0.001). Thrombotic events occurred in 27 of 263 patients (10.3%) receiving andexanet and in 15 of 267 (5.6%) receiving usual care (difference, 4.6 percentage points; 95% CI, 0.1 to 9.2; P = 0.048); ischemic stroke occurred in 17 patients (6.5%) and 4 patients (1.5%), respectively. There were no appreciable differences between the groups in the score on the modified Rankin scale or in death within 30 days. CONCLUSIONS: Among patients with intracerebral hemorrhage who were receiving factor Xa inhibitors, andexanet resulted in better control of hematoma expansion than usual care but was associated with thrombotic events, including ischemic stroke. (Funded by Alexion AstraZeneca Rare Disease and others; ANNEXA-I ClinicalTrials.gov number, NCT03661528.).


Asunto(s)
Hemorragia Cerebral , Inhibidores del Factor Xa , Factor Xa , Hematoma , Proteínas Recombinantes , Humanos , Inhibidores del Factor Xa/efectos adversos , Inhibidores del Factor Xa/uso terapéutico , Anciano , Masculino , Femenino , Hemorragia Cerebral/tratamiento farmacológico , Hemorragia Cerebral/inducido químicamente , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Proteínas Recombinantes/efectos adversos , Factor Xa/uso terapéutico , Factor Xa/efectos adversos , Hematoma/inducido químicamente , Hematoma/tratamiento farmacológico , Anciano de 80 o más Años , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/complicaciones , Enfermedad Aguda
6.
Brain ; 147(6): 2203-2213, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38797521

RESUMEN

Stuttering affects approximately 1 in 100 adults and can result in significant communication problems and social anxiety. It most often occurs as a developmental disorder but can also be caused by focal brain damage. These latter cases may lend unique insight into the brain regions causing stuttering. Here, we investigated the neuroanatomical substrate of stuttering using three independent datasets: (i) case reports from the published literature of acquired neurogenic stuttering following stroke (n = 20, 14 males/six females, 16-77 years); (ii) a clinical single study cohort with acquired neurogenic stuttering following stroke (n = 20, 13 males/seven females, 45-87 years); and (iii) adults with persistent developmental stuttering (n = 20, 14 males/six females, 18-43 years). We used the first two datasets and lesion network mapping to test whether lesions causing acquired stuttering map to a common brain network. We then used the third dataset to test whether this lesion-based network was relevant to developmental stuttering. In our literature dataset, we found that lesions causing stuttering occurred in multiple heterogeneous brain regions, but these lesion locations were all functionally connected to a common network centred around the left putamen, including the claustrum, amygdalostriatal transition area and other adjacent areas. This finding was shown to be specific for stuttering (PFWE < 0.05) and reproducible in our independent clinical cohort of patients with stroke-induced stuttering (PFWE < 0.05), resulting in a common acquired stuttering network across both stroke datasets. Within the common acquired stuttering network, we found a significant association between grey matter volume and stuttering impact for adults with persistent developmental stuttering in the left posteroventral putamen, extending into the adjacent claustrum and amygdalostriatal transition area (PFWE < 0.05). We conclude that lesions causing acquired neurogenic stuttering map to a common brain network, centred to the left putamen, claustrum and amygdalostriatal transition area. The association of this lesion-based network with symptom severity in developmental stuttering suggests a shared neuroanatomy across aetiologies.


Asunto(s)
Encéfalo , Accidente Cerebrovascular , Tartamudeo , Humanos , Tartamudeo/patología , Tartamudeo/etiología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Adolescente , Anciano , Anciano de 80 o más Años , Adulto Joven , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/patología , Imagen por Resonancia Magnética , Mapeo Encefálico/métodos
7.
Nature ; 570(7762): 468-473, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31142836

RESUMEN

Broadly neutralizing monoclonal antibodies protect against infection with HIV-1 in animal models, suggesting that a vaccine that elicits these antibodies would be protective in humans. However, it has not yet been possible to induce adequate serological responses by vaccination. Here, to activate B cells that express precursors of broadly neutralizing antibodies within polyclonal repertoires, we developed an immunogen, RC1, that facilitates the recognition of the variable loop 3 (V3)-glycan patch on the envelope protein of HIV-1. RC1 conceals non-conserved immunodominant regions by the addition of glycans and/or multimerization on virus-like particles. Immunization of mice, rabbits and rhesus macaques with RC1 elicited serological responses that targeted the V3-glycan patch. Antibody cloning and cryo-electron microscopy structures of antibody-envelope complexes confirmed that immunization with RC1 expands clones of B cells that carry the anti-V3-glycan patch antibodies, which resemble precursors of human broadly neutralizing antibodies. Thus, RC1 may be a suitable priming immunogen for sequential vaccination strategies in the context of polyclonal repertoires.


Asunto(s)
Vacunas contra el SIDA/inmunología , Linfocitos B/inmunología , Células Clonales/inmunología , VIH-1/química , VIH-1/inmunología , Macaca mulatta/inmunología , Vacunación , Secuencia de Aminoácidos , Animales , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/genética , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/ultraestructura , Afinidad de Anticuerpos , Especificidad de Anticuerpos/inmunología , Complejo Antígeno-Anticuerpo/inmunología , Linfocitos B/citología , Proliferación Celular , Células Clonales/citología , Clonación Molecular , Reactividad Cruzada/inmunología , Microscopía por Crioelectrón , Femenino , Anticuerpos Anti-VIH/química , Anticuerpos Anti-VIH/genética , Anticuerpos Anti-VIH/inmunología , Anticuerpos Anti-VIH/ultraestructura , Epítopos Inmunodominantes/química , Epítopos Inmunodominantes/inmunología , Epítopos Inmunodominantes/ultraestructura , Activación de Linfocitos , Masculino , Ratones , Modelos Moleculares , Polisacáridos/inmunología , Conejos , Hipermutación Somática de Inmunoglobulina
8.
Circulation ; 147(13): 1026-1038, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36802876

RESUMEN

BACKGROUND: Andexanet alfa is a modified recombinant inactive factor Xa (FXa) designed to reverse FXa inhibitors. ANNEXA-4 (Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of Factor Xa Inhibitors) was a multicenter, prospective, phase-3b/4, single-group cohort study that evaluated andexanet alfa in patients with acute major bleeding. The results of the final analyses are presented. METHODS: Patients with acute major bleeding within 18 hours of FXa inhibitor administration were enrolled. Co-primary end points were anti-FXa activity change from baseline during andexanet alfa treatment and excellent or good hemostatic efficacy, defined by a scale used in previous reversal studies, at 12 hours. The efficacy population included patients with baseline anti-FXa activity levels above predefined thresholds (≥75 ng/mL for apixaban and rivaroxaban, ≥40 ng/mL for edoxaban, and ≥0.25 IU/mL for enoxaparin; reported in the same units used for calibrators) who were adjudicated as meeting major bleeding criteria (modified International Society on Thrombosis and Haemostasis definition). The safety population included all patients. Major bleeding criteria, hemostatic efficacy, thrombotic events (stratified by occurring before or after restart of either prophylactic [ie, a lower dose, for prevention rather than treatment] or full-dose oral anticoagulation), and deaths were assessed by an independent adjudication committee. Median endogenous thrombin potential at baseline and across the follow-up period was a secondary outcome. RESULTS: There were 479 patients enrolled (mean age, 78 years; 54% male; 86% White); 81% were anticoagulated for atrial fibrillation, and the median time was 11.4 hours since last dose, with 245 (51%) on apixaban, 176 (37%) on rivaroxaban, 36 (8%) on edoxaban, and 22 (5%) on enoxaparin. Bleeding was predominantly intracranial (n=331 [69%]) or gastrointestinal (n=109 [23%]). In evaluable apixaban patients (n=172), median anti-FXa activity decreased from 146.9 ng/mL to 10.0 ng/mL (reduction, 93% [95% CI, 94-93]); in rivaroxaban patients (n=132), it decreased from 214.6 ng/mL to 10.8 ng/mL (94% [95% CI, 95-93]); in edoxaban patients (n=28), it decreased from 121.1 ng/mL to 24.4 ng/mL (71% [95% CI, 82-65); and in enoxaparin patients (n=17), it decreased from 0.48 IU/mL to 0.11 IU/mL (75% [95% CI, 79-67]). Excellent or good hemostasis occurred in 274 of 342 evaluable patients (80% [95% CI, 75-84]). In the safety population, thrombotic events occurred in 50 (10%) patients; in 16 patients, these occurred during treatment with prophylactic anticoagulation that began after the bleeding event. No thrombotic episodes occurred after oral anticoagulation restart. Specific to certain populations, reduction of anti-FXa activity from baseline to nadir significantly predicted hemostatic efficacy in patients with intracranial hemorrhage (area under the receiver operating characteristic curve, 0.62 [95% CI, 0.54-0.70]) and correlated with lower mortality in patients <75 years of age (adjusted P=0.022; unadjusted P=0.003). Median endogenous thrombin potential was within the normal range by the end of andexanet alfa bolus through 24 hours for all FXa inhibitors. CONCLUSIONS: In patients with major bleeding associated with the use of FXa inhibitors, treatment with andexanet alfa reduced anti-FXa activity and was associated with good or excellent hemostatic efficacy in 80% of patients. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02329327.


Asunto(s)
Hemostáticos , Trombosis , Anciano , Femenino , Humanos , Masculino , Anticoagulantes/efectos adversos , Estudios de Cohortes , Enoxaparina , Factor Xa/uso terapéutico , Inhibidores del Factor Xa/efectos adversos , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Hemostáticos/uso terapéutico , Estudios Prospectivos , Proteínas Recombinantes/efectos adversos , Rivaroxabán/efectos adversos , Trombina , Trombosis/tratamiento farmacológico
9.
Ann Neurol ; 94(3): 434-441, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37289520

RESUMEN

OBJECTIVE: Unawareness of a deficit, anosognosia, can occur for visual or motor deficits and lends insight into awareness itself; however, lesions associated with anosognosia occur in many different brain locations. METHODS: We analyzed 267 lesion locations associated with either vision loss (with and without awareness) or weakness (with and without awareness). The network of brain regions connected to each lesion location was computed using resting-state functional connectivity from 1,000 healthy subjects. Both domain specific and cross-modal associations with awareness were identified. RESULTS: The domain-specific network for visual anosognosia demonstrated connectivity to visual association cortex and posterior cingulate while motor anosognosia was defined by insula, supplementary motor area, and anterior cingulate connectivity. A cross-modal anosognosia network was defined by connectivity to the hippocampus and precuneus (false discovery rate p < 0.05). INTERPRETATION: Our results identify distinct network connections associated with visual and motor anosognosia and a shared, cross-modal network for awareness of deficits centered on memory-related brain structures. ANN NEUROL 2023;94:434-441.


Asunto(s)
Agnosia , Concienciación , Humanos , Encéfalo/patología , Corteza Cerebral , Giro del Cíngulo , Imagen por Resonancia Magnética/métodos
10.
Ann Neurol ; 93(3): 577-590, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36394118

RESUMEN

OBJECTIVE: Tuberous sclerosis complex (TSC) is associated with focal brain "tubers" and a high incidence of autism spectrum disorder (ASD). The location of brain tubers associated with autism may provide insight into the neuroanatomical substrate of ASD symptoms. METHODS: We delineated tuber locations for 115 TSC participants with ASD (n = 31) and without ASD (n = 84) from the Tuberous Sclerosis Complex Autism Center of Excellence Research Network. We tested for associations between ASD diagnosis and tuber burden within the whole brain, specific lobes, and at 8 regions of interest derived from the ASD neuroimaging literature, including the anterior cingulate, orbitofrontal and posterior parietal cortices, inferior frontal and fusiform gyri, superior temporal sulcus, amygdala, and supplemental motor area. Next, we performed an unbiased data-driven voxelwise lesion symptom mapping (VLSM) analysis. Finally, we calculated the risk of ASD associated with positive findings from the above analyses. RESULTS: There were no significant ASD-related differences in tuber burden across the whole brain, within specific lobes, or within a priori regions derived from the ASD literature. However, using VLSM analysis, we found that tubers involving the right fusiform face area (FFA) were associated with a 3.7-fold increased risk of developing ASD. INTERPRETATION: Although TSC is a rare cause of ASD, there is a strong association between tuber involvement of the right FFA and ASD diagnosis. This highlights a potentially causative mechanism for developing autism in TSC that may guide research into ASD symptoms more generally. ANN NEUROL 2023;93:577-590.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Esclerosis Tuberosa , Humanos , Trastorno del Espectro Autista/patología , Esclerosis Tuberosa/complicaciones , Encéfalo/patología , Neuroimagen , Imagen por Resonancia Magnética/métodos
11.
Epilepsia ; 65(4): 984-994, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38317356

RESUMEN

OBJECTIVE: Lead time to treatment (clinical onset of epileptic spasms [ES] to initiation of appropriate treatment) is known to predict outcomes in infantile epileptic spasms syndrome (IESS). Timing the clinical onset of ES is crucial to establish lead time. We investigated how often ES onset could be established to the nearest week. We aimed to (1) ascertain the exact date or estimate the nearest week of ES onset and (2) compare clinical/demographic factors between patients where date of ES onset was determined or estimated to the nearest week and patients whose date of ES onset could not be estimated to the nearest week. Reasons for difficulties in estimating date of ES onset were explored. METHODS: Retrospective chart review of new onset IESS patients (January 2019-May 2022) extracted the date or week of the clinical onset of ES. Predictors of difficulty in date of ES onset estimation to the nearest week were examined by regression analysis. Sources contributing to difficulties determining date of ES onset were assessed after grouping into categories (provider-, caregiver-, disease-related). RESULTS: Among 100 patients, date of ES onset was estimated to the nearest week in 47%. On univariable analysis, age at diagnosis (p = .021), development delay (p = .007), developmental regression/stagnation (p = .021), ES intermixed with other seizures (p = .011), and nonclustered ES at onset (p = .005) were associated with difficulties estimating date of ES onset. On multivariable analysis, failure to establish date of ES onset was related to ES intermixed with other seizures (p = .004) and nonclustered ES at onset (p = .003). Sources contributing to difficulties determining date of ES onset included disease-related factors (ES characteristics, challenges interpreting electroencephalograms) and provider/caregiver-related factors (delayed diagnosis). SIGNIFICANCE: Difficulties with estimation of lead time (due to difficulties timing ES onset) can impact clinical care (prognostication), as even small increments in lead time duration can have adverse developmental consequences.


Asunto(s)
Espasmos Infantiles , Humanos , Lactante , Estudios Retrospectivos , Edad de Inicio , Espasmos Infantiles/diagnóstico , Espasmos Infantiles/tratamiento farmacológico , Síndrome , Electroencefalografía , Convulsiones , Espasmo
12.
Future Oncol ; 20(9): 521-532, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38197229

RESUMEN

Aim: Treatment effects among anticoagulant-treated patients with venous thromboembolism (VTE) and cancer across tumor types were evaluated. Methods: Patients initiating an anticoagulant within 30 days after VTE were identified. After inverse probability treatment weighting, patients were stratified by tumor type. Interactions between treatment and tumor type on recurrent VTE, major bleeding and clinically relevant non-major bleeding were assessed using Cox proportional hazard models. Results: Treatment effects were generally not significantly different among patients with or without the following cancer types: prostate, breast, lung, pancreatic or multiple myeloma. Few significant interactions were observed for lung and pancreatic cancer. Conclusion: Anticoagulant treatment effects were generally consistent across tumor types. The significant interactions may indicate tumor-specific effects of anticoagulants, but further research is needed.


Asunto(s)
Anticoagulantes , Tromboembolia Venosa , Masculino , Humanos , Anticoagulantes/efectos adversos , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/etiología , Warfarina/efectos adversos , Recurrencia Local de Neoplasia , Hemorragia/inducido químicamente
13.
Artículo en Inglés | MEDLINE | ID: mdl-38735015

RESUMEN

BACKGROUND: Treating cancer-associated venous thromboembolism (CAT) with anticoagulation prevents recurrent venous thromboembolism (rVTE), but increases bleeding risk. OBJECTIVES: To compare incidence of rVTE, major bleeding, and all-cause mortality for rivaroxaban versus low molecular weight heparin (LMWH) in patients with CAT. METHODS: We developed a cohort study using Swedish national registers 2013-2019. Patients with CAT (venous thromboembolism within 6 months of cancer diagnosis) were included. Those with other indications or with high bleeding risk cancers were excluded (according to guidelines). Follow-up was from index-CAT until outcome, death, emigration, or end of study. Incidence rates (IR) per 1000 person-years with 95% confidence interval (CI) and propensity score overlap-weighted hazard ratios (HRs) for rivaroxaban versus LMWH were estimated. RESULTS: We included 283 patients on rivaroxaban and 5181 on LMWH. The IR for rVTE was 68.7 (95% CI 40.0-109.9) for rivaroxaban, compared with 91.6 (95% CI 81.9-102.0) for LMWH, with adjusted HR 0.77 (95% CI 0.43-1.35). The IR for major bleeding was 23.5 (95% CI 8.6-51.1) for rivaroxaban versus 49.2 (95% CI 42.3-56.9) for LMWH, with adjusted HR 0.62 (95% CI 0.26-1.49). The IR for all-cause mortality was 146.8 (95% CI 103.9-201.5) for rivaroxaban and 565.6 (95% CI 541.8-590.2) for LMWH with adjusted HR 0.48 (95% CI 0.34-0.67). CONCLUSIONS: Rivaroxaban performed similarly to LMWH for patients with CAT for rVTE and major bleeding. An all-cause mortality benefit was observed for rivaroxaban which potentially may be attributed to residual confounding. TRIAL REGISTRATION NUMBER: NCT05150938 (Registered 9 December 2021).

14.
Eur Heart J ; 44(14): 1231-1244, 2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-36648242

RESUMEN

AIMS: Deciding to stop or continue anticoagulation for venous thromboembolism (VTE) after initial treatment is challenging, as individual risks of recurrence and bleeding are heterogeneous. The present study aimed to develop and externally validate models for predicting 5-year risks of recurrence and bleeding in patients with VTE without cancer who completed at least 3 months of initial treatment, which can be used to estimate individual absolute benefits and harms of extended anticoagulation. METHODS AND RESULTS: Competing risk-adjusted models were derived to predict recurrent VTE and clinically relevant bleeding (non-major and major) using 14 readily available patient characteristics. The models were derived from combined individual patient data from the Bleeding Risk Study, Hokusai-VTE, PREFER-VTE, RE-MEDY, and RE-SONATE (n = 15,141, 220 recurrences, 189 bleeding events). External validity was assessed in the Danish VTE cohort, EINSTEIN-CHOICE, GARFIELD-VTE, MEGA, and Tromsø studies (n = 59 257, 2283 recurrences, 3335 bleeding events). Absolute treatment effects were estimated by combining the models with hazard ratios from trials and meta-analyses. External validation in different settings showed agreement between predicted and observed risks up to 5 years, with C-statistics ranging from 0.48-0.71 (recurrence) and 0.61-0.68 (bleeding). In the Danish VTE cohort, 5-year risks ranged from 4% to 19% for recurrent VTE and 1% -19% for bleeding. CONCLUSION: The VTE-PREDICT risk score can be applied to estimate the effect of extended anticoagulant treatment for individual patients with VTE and to support shared decision-making.


Asunto(s)
Tromboembolia Venosa , Humanos , Tromboembolia Venosa/tratamiento farmacológico , Recurrencia , Anticoagulantes/efectos adversos , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Factores de Riesgo
15.
Circulation ; 145(19): 1471-1479, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35389229

RESUMEN

BACKGROUND: Extended thromboprophylaxis has not been widely implemented in acutely ill medical patients because of bleeding concerns. The MAGELLAN (Multicenter, Randomized, Parallel Group Efficacy and Safety Study for the Prevention of Venous Thromboembolism in Hospitalized Medically Ill Patients Comparing Rivaroxaban With Enoxaparin) and MARINER (Medically Ill Patient Assessment of Rivaroxaban Versus Placebo in Reducing Post-Discharge Venous Thrombo-Embolism Risk) trials evaluated whether rivaroxaban compared with enoxaparin or placebo could prevent venous thromboembolism without increased bleeding. We hypothesized that patients with major bleeding but not those with nonmajor clinically relevant bleeding would be at an increased risk of all-cause mortality (ACM). METHODS: We evaluated all bleeding events in patients taking at least 1 dose of study drug and their association with ACM in 4 mutually exclusive groups: (1) no bleeding, or first event was (2) nonmajor clinically relevant bleeding, (3) major bleeding, or (4) trivial bleeding. Using a Cox proportional hazards model adjusted for differences in baseline characteristics associated with ACM, we assessed the risk of ACM after such events. RESULTS: Compared with patients with no bleeding, the risk of ACM for patients with nonmajor clinically relevant bleeding was not increased in MARINER (hazard ratio, 0.43; P=0.235) but was increased in MAGELLAN (hazard ratio, 1.74; P=0.021). Major bleeding was associated with a higher incidence of ACM in both studies, whereas trivial bleeding was not associated with ACM in either study. CONCLUSIONS: Patients with major bleeding had an increased risk of ACM, whereas nonmajor clinically relevant bleeding was not consistently associated with an increased risk of death. These results inform the risk-benefit calculus of extended thromboprophylaxis in medically ill patients. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: MAGELLAN, NCT00571649. URL: https://www. CLINICALTRIALS: gov; Unique identifier: MARINER, NCT02111564.


Asunto(s)
Rivaroxabán , Tromboembolia Venosa , Cuidados Posteriores , Anticoagulantes/efectos adversos , Enoxaparina/efectos adversos , Hemorragia/inducido químicamente , Hemorragia/complicaciones , Humanos , Alta del Paciente , Rivaroxabán/efectos adversos , Tromboembolia Venosa/epidemiología
16.
N Engl J Med ; 382(17): 1599-1607, 2020 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-32223112

RESUMEN

BACKGROUND: Recent guidelines recommend consideration of the use of oral edoxaban or rivaroxaban for the treatment of venous thromboembolism in patients with cancer. However, the benefit of these oral agents is limited by the increased risk of bleeding associated with their use. METHODS: This was a multinational, randomized, investigator-initiated, open-label, noninferiority trial with blinded central outcome adjudication. We randomly assigned consecutive patients with cancer who had symptomatic or incidental acute proximal deep-vein thrombosis or pulmonary embolism to receive oral apixaban (at a dose of 10 mg twice daily for the first 7 days, followed by 5 mg twice daily) or subcutaneous dalteparin (at a dose of 200 IU per kilogram of body weight once daily for the first month, followed by 150 IU per kilogram once daily). The treatments were administered for 6 months. The primary outcome was objectively confirmed recurrent venous thromboembolism during the trial period. The principal safety outcome was major bleeding. RESULTS: Recurrent venous thromboembolism occurred in 32 of 576 patients (5.6%) in the apixaban group and in 46 of 579 patients (7.9%) in the dalteparin group (hazard ratio, 0.63; 95% confidence interval [CI], 0.37 to 1.07; P<0.001 for noninferiority). Major bleeding occurred in 22 patients (3.8%) in the apixaban group and in 23 patients (4.0%) in the dalteparin group (hazard ratio, 0.82; 95% CI, 0.40 to 1.69; P = 0.60). CONCLUSIONS: Oral apixaban was noninferior to subcutaneous dalteparin for the treatment of cancer-associated venous thromboembolism without an increased risk of major bleeding. (Funded by the Bristol-Myers Squibb-Pfizer Alliance; Caravaggio ClinicalTrials.gov number, NCT03045406.).


Asunto(s)
Anticoagulantes/administración & dosificación , Dalteparina/administración & dosificación , Hemorragia/inducido químicamente , Neoplasias/complicaciones , Pirazoles/administración & dosificación , Piridonas/administración & dosificación , Prevención Secundaria/métodos , Tromboembolia Venosa/prevención & control , Administración Oral , Anciano , Anticoagulantes/efectos adversos , Dalteparina/efectos adversos , Femenino , Hemorragia/epidemiología , Humanos , Incidencia , Inyecciones Subcutáneas , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , Modelos de Riesgos Proporcionales , Embolia Pulmonar/prevención & control , Pirazoles/efectos adversos , Piridonas/efectos adversos , Método Simple Ciego , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/etiología , Trombosis de la Vena/prevención & control
17.
Ann Neurol ; 91(2): 217-224, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34961965

RESUMEN

OBJECTIVE: Blindsight is a disorder where brain injury causes loss of conscious but not unconscious visual perception. Prior studies have produced conflicting results regarding the neuroanatomical pathways involved in this unconscious perception. METHODS: We performed a systematic literature search to identify lesion locations causing visual field loss in patients with blindsight (n = 34) and patients without blindsight (n = 35). Resting state functional connectivity between each lesion location and all other brain voxels was computed using a large connectome database (n = 1,000). Connections significantly associated with blindsight (vs no blindsight) were identified. RESULTS: Functional connectivity between lesion locations and the ipsilesional medial pulvinar was significantly associated with blindsight (family wise error p = 0.029). No significant connectivity differences were found to other brain regions previously implicated in blindsight. This finding was independent of methods (eg, flipping lesions to the left or right) and stimulus type (moving vs static). INTERPRETATION: Connectivity to the ipsilesional medial pulvinar best differentiates lesion locations associated with blindsight versus those without blindsight. Our results align with recent data from animal models and provide insight into the neuroanatomical substrate of unconscious visual abilities in patients. ANN NEUROL 2022;91:217-224.


Asunto(s)
Red Nerviosa/fisiopatología , Inconsciencia/psicología , Percepción Visual , Adulto , Anciano , Mapeo Encefálico , Conectoma , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Pulvinar/diagnóstico por imagen , Pulvinar/fisiopatología , Descanso , Trastornos de la Visión , Campos Visuales , Adulto Joven
18.
Phys Rev Lett ; 130(25): 258402, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37418715

RESUMEN

Spectral mode representations play an essential role in various areas of physics, from quantum mechanics to fluid turbulence, but they are not yet extensively used to characterize and describe the behavioral dynamics of living systems. Here, we show that mode-based linear models inferred from experimental live-imaging data can provide an accurate low-dimensional description of undulatory locomotion in worms, centipedes, robots, and snakes. By incorporating physical symmetries and known biological constraints into the dynamical model, we find that the shape dynamics are generically governed by Schrödinger equations in mode space. The eigenstates of the effective biophysical Hamiltonians and their adiabatic variations enable the efficient classification and differentiation of locomotion behaviors in natural, simulated, and robotic organisms using Grassmann distances and Berry phases. While our analysis focuses on a widely studied class of biophysical locomotion phenomena, the underlying approach generalizes to other physical or living systems that permit a mode representation subject to geometric shape constraints.


Asunto(s)
Robótica , Locomoción
19.
J Thromb Thrombolysis ; 56(2): 233-240, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37338712

RESUMEN

Acute bleeding is common and associated with increased morbidity and mortality. Epidemiological studies evaluating trends in bleeding-related hospitalisations and mortality are important as they have potential to guide resource allocation and service provision, however, despite this literature evaluating the national burden and annual trends are lacking. Our objective was to report the national burden and incidence of bleeding-related hospitalisation and mortality.This was a population-based review of all people in England between 2014 and 2019 either admitted to an acute care ward of a National Health Service (NHS) English hospital, or who died. Admissions and deaths were required to have a primary diagnosis of significant bleeding.There was a total of 3,238,427 hospitalisations with a mean of 539,738 ± 6033 per year and 81,264 deaths with a mean of 13,544 ± 331 per year attributable to bleeding. The mean annual incident rate for bleeding-related hospitalisations was 975 per 100,000 patient years and for mortality was 24.45. Over the study period there was a significant 8.2% reduction in bleeding related deaths (χ2 test for trend 91.4, p < 0.001). A direct relationship between increasing age and incidence of bleeding-related hospitalisation and mortality was seen.Bleeding remains a common cause of hospitalisation and death. The reduction in bleeding related mortality requires further investigation. This data may serve to guide future interventions designed to reduce bleeding-related morbidity and mortality.


Asunto(s)
Hospitalización , Medicina Estatal , Humanos , Inglaterra/epidemiología , Incidencia , Hospitales
20.
J Thromb Thrombolysis ; 55(2): 211-221, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36566304

RESUMEN

The ADA (Age-D-dimer-Albumin) score was developed to identify hospitalized patients at an increased risk for thrombosis in the coronavirus infectious disease-19 (COVID-19) setting. The study aimed to validate the ADA score for predicting thrombosis in a non-COVID-19 medically ill population from the APEX trial. The APEX trial was a multinational, randomized trial that evaluated the efficacy and safety of betrixaban vs. enoxaparin among acutely ill hospitalized patients at risk for venous thromboembolism. The study endpoints included the composite of arterial or venous thrombosis and its components. Metrics of model calibration and discrimination were computed for assessing the performance of the ADA score as compared to the IMPROVE score, a well-validated VTE risk assessment model. Among 7,119 medical inpatients, 209 (2.9%) had a thrombosis event up to 77 days of follow-up. The ADA score demonstrated good calibration for both arterial and venous thrombosis, whereas the IMPROVE score had adequate calibration for venous thrombosis (p > 0.05 from the Hosmer-Lemeshow test). For discriminating arterial and venous thrombosis, there was no significant difference between the ADA vs. IMPROVE score (c statistic = 0.620 [95% CI: 0.582 to 0.657] vs. 0.590 [95% CI: 0.556 to 0.624]; ∆ c statistic = 0.030 [95% CI: -0.022 to 0.081]; p = 0.255). Similarly, for discriminating arterial thrombosis, there was no significant difference between the ADA vs. IMPROVE score (c statistic = 0.582 [95% CI: 0.534 to 0.629] vs. 0.609 [95% CI: 0.564 to 0.653]; ∆ c statistic = -0.027 [95% CI: -0.091 to 0.036]; p = 0.397). For discriminating venous thrombosis, the ADA score was modestly superior to the IMPROVE score (c statistic = 0.664 [95% CI: 0.607 to 0.722] vs. 0.573 [95% CI: 0.521 to 0.624]; ∆ c statistic = 0.091 [95% CI: 0.011 to 0.172]; p = 0.026). The ADA score had a higher sensitivity (0.579 [95% CI: 0.512 to 0.646]; vs. 0.440 [95% CI: 0.373 to 0.507]) but lower specificity (0.625 [95% CI: 0.614 to 0.637] vs. 0.747 [95% CI: 0.737 to 0.758]) than the IMPROVE score for predicting thrombosis. Among acutely ill hospitalized medical patients enrolled in the APEX trial, the ADA score demonstrated good calibration but suboptimal discrimination for predicting thrombosis. The findings support the use of either the ADA or IMPROVE score for thrombosis risk assessment. The applicability of the ADA score to non-COVID-19 populations warrants further research.Clinical Trial Registration: http://www.clinicaltrials.gov . Unique identifier: NCT01583218.


Asunto(s)
COVID-19 , Tromboembolia Venosa , Trombosis de la Vena , Humanos , COVID-19/complicaciones , Enoxaparina/uso terapéutico , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/tratamiento farmacológico , Trombosis de la Vena/inducido químicamente , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/inducido químicamente , Medición de Riesgo , Anticoagulantes/uso terapéutico , Factores de Riesgo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA