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1.
Small ; 20(19): e2307045, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38100142

RESUMEN

Since WHO has declared the COVID-19 outbreak a global pandemic, nearly seven million deaths have been reported. This efficient spread of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is facilitated by the ability of the spike glycoprotein to bind multiple cell membrane receptors. Although ACE2 is identified as the main receptor for SARS-CoV-2, other receptors could play a role in viral entry. Among others, C-type lectins such as DC-SIGN are identified as efficient trans-receptor for SARS-CoV-2 infection, so the use of glycomimetics to inhibit the infection through the DC-SIGN blockade is an encouraging approach. In this regard, multivalent nanostructures based on glycosylated [60]fullerenes linked to a central porphyrin scaffold have been designed and tested against DC-SIGN-mediated SARS-CoV-2 infection. First results show an outstanding inhibition of the trans-infection up to 90%. In addition, a deeper understanding of nanostructure-receptor binding is achieved through microscopy techniques, high-resolution NMR experiments, Quartz Crystal Microbalance experiments, and molecular dynamic simulations.


Asunto(s)
Moléculas de Adhesión Celular , Fulerenos , Lectinas Tipo C , Porfirinas , Receptores de Superficie Celular , SARS-CoV-2 , Humanos , Moléculas de Adhesión Celular/metabolismo , Moléculas de Adhesión Celular/antagonistas & inhibidores , COVID-19/virología , Tratamiento Farmacológico de COVID-19 , Fulerenos/química , Fulerenos/farmacología , Lectinas Tipo C/metabolismo , Lectinas Tipo C/antagonistas & inhibidores , Simulación de Dinámica Molecular , Porfirinas/química , Porfirinas/farmacología , Unión Proteica , Receptores de Superficie Celular/metabolismo , Receptores de Superficie Celular/antagonistas & inhibidores , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/metabolismo , Glicoproteína de la Espiga del Coronavirus/química
2.
Carbohydr Polym ; 318: 121094, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37479429

RESUMEN

Lipopolysaccharides (LPS) are major players in bacterial infection through the recognition by Toll-like receptor 4 (TLR4). The LPS chemical structure, including the oligosaccharide core and the lipid A moiety, can be strongly influenced by adaptation and modulated to assure bacteria protection, evade immune surveillance, or reduce host immune responses. Deep structural understanding of TLRs signaling is essential for the modulation of the innate immune system in sepsis control and inflammation, during bacterial infection. To advance this knowledge, we have employed computational techniques to characterize the TLR4 molecular recognition of atypical LPSs from different opportunistic members of α2-Proteobacteria, including Brucella melitensis, Ochrobactrum anthropi, and Ochrobactrum intermedium, with diverse immunostimulatory activities. We contribute to unraveling the role of uncommon lipid A chemical features such as bearing very long-chain fatty acid chains, whose presence has been rarely reported, on modulating the proper heterodimerization of the TLR4 receptor complex. Moreover, we further evaluated the influence of the different oligosaccharide cores, including sugar composition and net charge, on TLR4 activation. Our studies contribute to elucidating, from the molecular and biological perspectives, the impact of the α2-Proteobacteria LPS cores and the chemical structure of the atypical lipid A for immune system evasion in opportunistic bacteria.


Asunto(s)
Infecciones Bacterianas , Lipopolisacáridos , Humanos , Lipopolisacáridos/química , Receptor Toll-Like 4 , Lípido A/química , Proteobacteria , Evasión Inmune , Bacterias , Oligosacáridos
3.
Aging Cell ; 22(3): e13771, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36704839

RESUMEN

The enormous societal impact of the ongoing COVID-19 pandemic has been particularly harsh for some social groups, such as the elderly. Recently, it has been suggested that senescent cells could play a central role in pathogenesis by exacerbating the pro-inflammatory immune response against SARS-CoV-2. Therefore, the selective clearance of senescent cells by senolytic drugs may be useful as a therapy to ameliorate the symptoms of COVID-19 in some cases. Using the established COVID-19 murine model K18-hACE2, we demonstrated that a combination of the senolytics dasatinib and quercetin (D/Q) significantly reduced SARS-CoV-2-related mortality, delayed its onset, and reduced the number of other clinical symptoms. The increase in senescent markers that we detected in the lungs in response to SARS-CoV-2 may be related to the post-COVID-19 sequelae described to date. These results place senescent cells as central targets for the treatment of COVID-19, and make D/Q a new and promising therapeutic tool.


Asunto(s)
COVID-19 , Quercetina , Ratones , Humanos , Animales , Quercetina/farmacología , Quercetina/uso terapéutico , Dasatinib/farmacología , Dasatinib/uso terapéutico , SARS-CoV-2 , Senescencia Celular , Senoterapéuticos , Pandemias
5.
Front Immunol ; 12: 660065, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34234775

RESUMEN

Toll-like receptors (TLRs) play a crucial role in the recognition of pathogen-derived components as a first line of defense against infections. It has been suggested that depending on the nature of the pathogens, TLRs activation induce a distinct cytokine profile that may contribute to the polarization of the acquired immune response. Here, we investigated the early MAPK signaling activation via TLR4 and TLR2 receptors and its impact in differential cytokine profile by macrophages. We found that TLR2 ligands activated MAPKs p38 and ERK earlier compared to the TLR4 ligand LPS in macrophages. Higher IL-10/IL-12 and IL-10/TNF-α ratios were also observed at later time points in response to TLR2 ligands compared to LPS. The results also indicate an earlier activation of the phosphatase MKP-1 and that MKP-1 KO macrophages show a prolongation in p38 phosphorylation in response to TLR2 stimulation. Furthermore, p38 is critical for IL-10 expression in response to TLR2 ligands, which triggers the macrophage change to a M2 and regulatory phenotype in contrast to the M1 phenotype induced by TLR4 activation. Therefore, the early TLR2-mediated p38 induction contributes for the high IL-10 production, likely as a virulence strategy to suppress host Th1 response against certain types of pathogens.


Asunto(s)
Fosfatasa 1 de Especificidad Dual/inmunología , Interleucina-10/inmunología , Macrófagos/inmunología , Receptor Toll-Like 2/inmunología , Proteínas Quinasas p38 Activadas por Mitógenos/inmunología , Animales , Células Cultivadas , Citocinas/genética , Citocinas/inmunología , Citocinas/metabolismo , Diglicéridos/farmacología , Fosfatasa 1 de Especificidad Dual/genética , Fosfatasa 1 de Especificidad Dual/metabolismo , Activación Enzimática/inmunología , Expresión Génica/efectos de los fármacos , Expresión Génica/inmunología , Interleucina-10/genética , Interleucina-10/metabolismo , Lipopéptidos/farmacología , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Oligopéptidos/farmacología , Fosforilación/efectos de los fármacos , Células RAW 264.7 , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/inmunología , Receptor Toll-Like 4/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
6.
Front Immunol ; 12: 748303, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35140704

RESUMEN

The Toll-like receptor 4 (TLR4)/myeloid differentiation protein-2 (MD-2) complex is considered the major receptor of the innate immune system to recognize lipopolysaccharides (LPSs). However, some atypical LPSs with different lipid A and core saccharide moiety structures and compositions than the well-studied enterobacterial LPSs can induce a TLR2-dependent response in innate immune cells. Ochrobactrum intermedium, an opportunistic pathogen, presents an atypical LPS. In this study, we found that O. intermedium LPS exhibits a weak inflammatory activity compared to Escherichia coli LPS and, more importantly, is a specific TLR4/TLR2 agonist, able to signal through both receptors. Molecular docking analysis of O. intermedium LPS predicts a favorable formation of a TLR2/TLR4/MD-2 heterodimer complex, which was experimentally confirmed by fluorescence resonance energy transfer (FRET) in cells. Interestingly, the core saccharide plays an important role in this interaction. This study reveals for the first time TLR4/TLR2 heterodimerization that is induced by atypical LPS and may help to escape from recognition by the innate immune system.


Asunto(s)
Endotoxinas/farmacología , Lipopolisacáridos/farmacología , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Línea Celular , Células HEK293 , Humanos , Inmunidad Innata/efectos de los fármacos , Inflamación/metabolismo , Lípido A/farmacología , Ratones Endogámicos C57BL , Ratones Noqueados , Simulación del Acoplamiento Molecular
7.
Viral Immunol ; 29(10): 583-585, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27834618

RESUMEN

Rabbit hemorrhagic disease virus (RHDVb) is the new variant of the classical RHDV, a virulent pathogen responsible for an acute disease in young rabbits. The virus invades internal organs, especially the liver, spleen, kidneys, and gut; prevents coagulation; and causes liver necrosis. This eventually leads to quick death of the animal because of hemorrhage. In this study, we evaluated the effects of a new vaccine against RHDVb in rabbits at a young age, after experimental infection using four different viral isolates. Our findings show that the vaccine had a protective effect with survival rates reaching 80-100% against the different isolates. These results suggest that this vaccine, when applied to young animals, is an effective tool to protect against the disease caused by RHDVb in rabbitries.


Asunto(s)
Infecciones por Caliciviridae/prevención & control , Infecciones por Caliciviridae/veterinaria , Virus de la Enfermedad Hemorrágica del Conejo/inmunología , Vacunas Virales/inmunología , Animales , Infecciones por Caliciviridae/mortalidad , Conejos , Tasa de Supervivencia , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Vacunas Virales/administración & dosificación
9.
Rev. enferm. neurol ; 19(1): 32-37, 20200430.
Artículo en Español | LILACS, BDENF - enfermagem (Brasil) | ID: biblio-1253409

RESUMEN

Introdución: cada vez son más los hombres que deciden ejercer la profesión de enfermería, lo cual supone cambios en la visión que tienen los propios enfermeros sobre su desempeño. Objetivo: describir las experiencias de los enfermeros en el desempeño de su profesión. Material y metodos: se empleó un diseño de investigación cualitativa, de corte fenomenológico descriptivo. Se realizó una entrevista semiestructurada a ocho profesionales de enfermería de sexo masculino que se desempeñan en algún rol de la profesión de enfermería. Resultados: la mayoría de los enfermeros entrevistados manifestaron: es un reto estar en enfermería en el contexto social actual, debido a las opiniones desfavorables respecto a su desempeño. Sin embargo, también coinciden en sentirse identificados con la carrera, cuidado y quehacer de la enfermería Conclusión: los profesionales de enfermería varones se enfrentan aún con varios retos en el camino de un reconocimiento cabal de su quehacer profesional.


Asunto(s)
Humanos , Enfermeros , Percepción , Rol Profesional , Aprendizaje
13.
Rev. senol. patol. mamar. (Ed. impr.) ; 27(2): 74-79, abr.-jun. 2014.
Artículo en Español | IBECS (España) | ID: ibc-122193

RESUMEN

Objetivo. Analizar las diferencias en volumen, duración del drenaje axilar y estancia hospitalaria en las pacientes a las que se les realizó linfadenectomía axilar con bisturí armónico (Focus®) y una plancha de colágeno, fibrinógeno y trombina (TachoSil(R)) frente a linfadenectomía convencional con bisturí eléctrico monopolar. Pacientes y métodos. Se realizó un estudio prospectivo aleatorizado, sobre una cohorte de base hospitalaria durante el periodo 2008-2011, en 77 linfadenectomías, aleatorizando a las pacientes por cirugía clásica (control) frente a bisturí armónico y la plancha de TachoSil(R). Se compararon ambos grupos en cuanto a estancia, volumen y débito del drenaje axilar. Se recogieron variables como el tipo de tumor y tamaño, el número de ganglios resecados y afectados, el nivel de la linfadenectomía, el tipo de cirugía realizada y la edad. Resultados. Se incluyeron 37 linfadenectomías correspondientes al grupo de casos con bisturí armónico y plancha de colágeno, y 40 al grupo control con bisturí eléctrico. Se obtuvo una reducción de la estancia media (4,25 frente a 6,1 días) con respecto al grupo control, así como en la duración del débito (6,3 frente a 9,5 días) y el volumen total del mismo (330 frente a 550 cc), obteniendo todos ellos significación estadística. Conclusiones. La linfadenectomía con bisturí armónico dejando una plancha de colágeno y trombina disminuyen la estancia hospitalaria, los días necesarios para retirar el drenaje axilar y el débito del mismo (AU)


Objective. To analyze differences in lymphorrhea volume, the duration of axillary drainage, and length of hospital stay in patients who underwent axillary dissection with the harmonic scalpel (Focus®) and a sheet of collagen, fibrinogen and thrombin (TachoSil(R)) versus conventional lymphadenectomy with monopolar electrocautery. Patients and methods. We performed a prospective randomized study in a hospital-based cohort from 2008 to 2011. Seventy-seven patients were randomized to lymphadenectomy using traditional surgery (control group) versus the harmonic scalpel and TachoSil(R) sheet. Length of hospital stay and axillary drainage volume and duration were compared between the 2 groups. The variables collected included the type and size of the tumor, the number of lymph nodes removed and involved, the level of lymphadenectomy, type of surgery, and age. Results. There were 37 patients in the group that underwent lymphadenectomy with the harmonic scalpel and collagen sheet and 40 in the control group who underwent conventional lymphadenectomy with electrocautery. Compared with the control group, the harmonic scalpel and collagen sheet group showed reductions in the mean length of hospital stay (6.1 versus 4.25 days), the duration of lymphorrhea (9.5 versus 6.3 days), and the total volume (550 versus 330 cc); all these differences were statistically significant. Conclusions. Axillary dissection with the harmonic scalpel and a single sheet of collagen and thrombin decreases length of hospital stay, the days necessary to remove the axillary drainage, and lymphorrhea volume (AU)


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , /métodos , Escisión del Ganglio Linfático/instrumentación , Escisión del Ganglio Linfático/métodos , Linfedema/cirugía , Colágeno/uso terapéutico , Escisión del Ganglio Linfático/normas , Escisión del Ganglio Linfático , /métodos , /tendencias , Estudios Prospectivos , Estudios de Cohortes , Consentimiento Informado/normas
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