Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Más filtros

Bases de datos
Tipo de estudio
Tipo del documento
Intervalo de año de publicación
1.
Microbiol Spectr ; 12(6): e0000424, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38747636

RESUMEN

Kidney transplant recipients (KTRs) have been identified as a population at increased risk for severe SARS-CoV-2 infection outcomes. This study focused on understanding the immune response of KTRs post-vaccination, specifically examining both serological and cellular responses to the SARS-CoV-2 vaccine. Thirteen individuals, including seven KTRs and six healthy donors, were evaluated for antibody levels and T cell responses post-vaccination. The study revealed that KTRs had significantly lower serological responses, including reduced anti-receptor binding domain (RBD) binding antibodies and neutralizing antibodies against the Wuhan, Delta, and Omicron BA.2 strains. Additionally, KTRs demonstrated weaker CD8 T cell cytotoxic responses and lower Th1 cytokine secretion, particularly IFN-γ, after stimulation with variant spike peptide pools. These findings highlight the compromised immunity in KTRs post-vaccination and underscore the need for tailored strategies to bolster immune responses in this vulnerable group. Further investigations are warranted into the mechanisms underlying reduced vaccine efficacy in KTRs and potential therapeutic interventions. IMPORTANCE: Some studies have revealed that KTRs had lower serological response against SARS-CoV-2 than healthy people. Nevertheless, limited studies investigate the cellular response against SARS-CoV-2 in KTRs receiving SARS-CoV-2 vaccines. Here, we found that KTRs have lower serological and cellular responses. Moreover, we found that KTRs had a significantly lower IFN-γ secretion than healthy individuals when their PBMCs were stimulated with SARS-CoV-2 spike peptide pools. Thus, our findings suggested that additional strategies are needed to enhance KTR immunity triggered by the vaccine.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Trasplante de Riñón , SARS-CoV-2 , Receptores de Trasplantes , Humanos , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Trasplante de Riñón/efectos adversos , COVID-19/inmunología , COVID-19/prevención & control , SARS-CoV-2/inmunología , Persona de Mediana Edad , Masculino , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Femenino , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Adulto , Glicoproteína de la Espiga del Coronavirus/inmunología , Anciano , Linfocitos T CD8-positivos/inmunología , Vacunación , Interferón gamma/inmunología , Interferón gamma/metabolismo
2.
Phys Rev Lett ; 110(3): 033002, 2013 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-23373919

RESUMEN

From the perspective of perturbation theory, we propose a systematic procedure for the evaluation of the derivative discontinuity (DD) of the exchange-correlation energy functional in Kohn-Sham (KS) density functional theory, wherein the exact DD can in principle be obtained by summing up all the perturbation corrections to infinite order. Truncation of the perturbation series at low order yields an efficient scheme for obtaining the approximate DD. While the zeroth-order theory yields a vanishing DD, the first-order correction to the DD can be expressed as an explicit universal functional of the ground-state density and the KS lowest unoccupied molecular orbital density, allowing the direct evaluation of the DD in the standard KS method without extra computational cost. The fundamental gap can be predicted by adding the estimated DD to the KS gap. This scheme is shown to be accurate in the prediction of the fundamental gaps for a wide variety of atoms and molecules.

3.
J Chem Phys ; 138(16): 164101, 2013 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-23635105

RESUMEN

Restricted open-shell Kohn-Sham (ROKS) theory provides a powerful computational tool for calculating singlet excited state energies and dynamics. However, the possibility of multiple solutions to the ROKS equations - with the associated difficulty of automatically selecting the physically meaningful solution - limits its usefulness for intensive applications such as long-time Born-Oppenheimer molecular dynamics. We present an implementation of ROKS for excited states which prescribes the physically correct solution from an overlap criterion and guarantees that this solution is stationary, allowing for straightforward evaluation of nuclear gradients. The method is used to benchmark ROKS for vertical excitation energies of small and large organic dyes and for the calculation of Stokes shifts. With common density functional approximations, ROKS vertical excitation energies, and Stokes shifts show similar accuracy to those from time-dependent density functional theory and Δ-self-consistent-field approaches. Advantages of the ROKS approach for excited state structure and molecular dynamics are discussed.


Asunto(s)
Simulación de Dinámica Molecular , Teoría Cuántica
4.
ArXiv ; 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37131882

RESUMEN

Transcription commonly occurs in bursts, with alternating productive (ON) and quiescent (OFF) periods, governing mRNA production rates. Yet, how transcription is regulated through bursting dynamics remains unresolved. In this study, we conduct real-time measurements of endogenous transcriptional bursting with single-mRNA sensitivity. Leveraging the diverse transcriptional activities in early fly embryos, we uncover stringent relationships between bursting parameters. Specifically, we find that the durations of ON and OFF periods are linked. Regardless of the developmental stage or body-axis position, gene activity levels predict the average ON and OFF periods of individual alleles. Lowly transcribing alleles predominantly modulate OFF durations (burst frequency), while highly transcribing alleles primarily tune ON durations (burst size). Importantly, these relationships persist even under perturbation of cis-regulatory elements or trans-factors. This suggests a novel mechanistic constraint governing bursting dynamics rather than a modular control of distinct parameters by distinct regulatory processes. Our study provides a foundation for future investigations into the molecular mechanisms underpinning spatiotemporal transcriptional control.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA