7,427 research outputs found

    A high-affinity antibody against the CSP N-terminal domain lacks Plasmodium falciparum inhibitory activity

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    Malaria is a global health concern and research efforts are ongoing to develop a superior vaccine to RTS,S/AS01. To guide immunogen design, we seek a comprehensive understanding of the protective humoral response against Plasmodium falciparum circumsporozoite protein (PfCSP). In contrast to the well-studied responses to the repeat region and the C-terminus, the antibody response against the N-terminal domain of PfCSP (N-CSP) remains obscure. Here, we characterized the molecular recognition and functional efficacy of the N-CSP-specific monoclonal antibody 5D5. The crystal structure at 1.85 Åresolution revealed that 5D5 binds an α-helical epitope in N-CSP with high affinity through extensive shape and charge complementarity, and the unusual utilization of an N-linked glycan. Nevertheless, functional studies indicated low 5D5 binding to live Pf sporozoites, and lack of sporozoite inhibition in vitro and in mosquitoes. Overall, our data on low recognition and inhibition of sporozoites do not support the inclusion of the 5D5 epitope into the next generation of CSP-based vaccines.Summary Statement The Plasmodium falciparum sporozoite surface protein, PfCSP, is an attractive vaccine target, but the antibody response against the CSP N-terminal domain has remained understudied. Here, to guide immunogen design, Thai et al. provide insights into the binding motif and functional efficacy of the N-terminal domain-specific monoclonal antibody, 5D5

    The effects of advanced maternal age on T- cell subsets at the maternal- fetal interface prior to term labor and in the offspring: a mouse study

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155904/1/cei13437.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155904/2/cei13437_am.pd

    Ballistic Electron Emission Microscopy on CoSi2{}_2/Si(111) interfaces: band structure induced atomic-scale resolution and role of localized surface states

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    Applying a Keldysh Green`s function method it is shown that hot electrons injected from a STM-tip into a CoSi2{}_2/Si(111) system form a highly focused beam due to the silicide band structure. This explains the atomic resolution obtained in recent Ballistic Electron Emission Microscopy (BEEM) experiments. Localized surface states in the (2×1)(2 \times 1)-reconstruction are found to be responsible for the also reported anticorrugation of the BEEM current. These results clearly demonstrate the importance of bulk and surface band structure effects for a detailed understanding of BEEM data.Comment: 5 pages, RevTex, 4 postscript figures, http://www.icmm.csic.es/Pandres/pedro.ht

    An NF-κB-microRNA regulatory network tunes macrophage inflammatory responses

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    The innate inflammatory response must be tightly regulated to ensure effective immune protection. NF-κB is a key mediator of the inflammatory response, and its dysregulation has been associated with immune-related malignancies. Here, we describe a miRNA-based regulatory network that enables precise NF-κB activity in mouse macrophages. Elevated miR-155 expression potentiates NF-κB activity in miR-146a-deficient mice, leading to both an overactive acute inflammatory response and chronic inflammation. Enforced miR-155 expression overrides miR-146a-mediated repression of NF-κB activation, thus emphasizing the dominant function of miR-155 in promoting inflammation. Moreover, miR-155-deficient macrophages exhibit a suboptimal inflammatory response when exposed to low levels of inflammatory stimuli. Importantly, we demonstrate a temporal asymmetry between miR-155 and miR-146a expression during macrophage activation, which creates a combined positive and negative feedback network controlling NF-κB activity. This miRNA-based regulatory network enables a robust yet time-limited inflammatory response essential for functional immunity

    A novel PKC activating molecule promotes neuroblast differentiation and delivery of newborn neurons in brain injuries

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    Neural stem cells are activated within neurogenic niches in response to brain injuries. This results in the production of neuroblasts, which unsuccessfully attempt to migrate toward the damaged tissue. Injuries constitute a gliogenic/non-neurogenic niche generated by the presence of anti-neurogenic signals, which impair neuronal differentiation and migration. Kinases of the protein kinase C (PKC) family mediate the release of growth factors that participate in different steps of the neurogenic process, particularly, novel PKC isozymes facilitate the release of the neurogenic growth factor neuregulin. We have demonstrated herein that a plant derived diterpene, (EOF2; CAS number 2230806-06-9), with the capacity to activate PKC facilitates the release of neuregulin 1, and promotes neuroblasts differentiation and survival in cultures of subventricular zone (SVZ) isolated cells in a novel PKC dependent manner. Local infusion of this compound in mechanical cortical injuries induces neuroblast enrichment within the perilesional area, and noninvasive intranasal administration of EOF2 promotes migration of neuroblasts from the SVZ towards the injury, allowing their survival and differentiation into mature neurons, being some of them cholinergic and GABAergic. Our results elucidate the mechanism of EOF2 promoting neurogenesis in injuries and highlight the role of novel PKC isozymes as targets in brain injury regeneration

    Unusual Thermodynamics on the Fuzzy 2-Sphere

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    Higher spin Dirac operators on both the continuum sphere(S2S^2) and its fuzzy analog(SF2S^2_F) come paired with anticommuting chirality operators. A consequence of this is seen in the fermion-like spectrum of these operators which is especially true even for the case of integer-spin Dirac operators. Motivated by this feature of the spectrum of a spin 1 Dirac operator on SF2S_F^2, we assume the spin 1 particles obey Fermi-Dirac statistics. This choice is inspite of the lack of a well defined spin-statistics relation on a compact surface such as S2S^2. The specific heats are computed in the cases of the spin 12\frac{1}{2} and spin 1 Dirac operators. Remarkably the specific heat for a system of spin 12\frac{1}{2} particles is more than that of the spin 1 case, though the number of degrees of freedom is more in the case of spin 1 particles. The reason for this is inferred through a study of the spectrums of the Dirac operators in both the cases. The zero modes of the spin 1 Dirac operator is studied as a function of the cut-off angular momentum LL and is found to follow a simple power law. This number is such that the number of states with positive energy for the spin 1 and spin 12\frac{1}{2} system become comparable. Remarks are made about the spectrums of higher spin Dirac operators as well through a study of their zero-modes and the variation of their spectrum with degeneracy. The mean energy as a function of temperature is studied in both the spin 12\frac{1}{2} and spin 1 cases. They are found to deviate from the standard ideal gas law in 2+1 dimensions.Comment: 19 pages, 7 figures. The paper has been significantly modified. Main results are unchange

    Desarrollo evolutivo de las competencias laborales: una revisión de la literatura

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    Objective. To identify the theoretical approaches on labor competencies in the period 2010-2021. Methodology. This research is a review article that uses as a tool the PRISMA 2009 Protocol, by means of which it was possible to select the articles according to certain criteria such as inclusion and exclusion. Results. The study conducted on labor competencies showed that during the period 2010-2021, the number of review articles increased considerably, of which 35 articles that passed through various filters were taken into account. Conclusion. It was possible to appreciate the existence of a greater elaboration of research between 2019 and 2020, giving greater emphasis to this variable, since the construct of labor competencies reveals a whole set of knowledge, skills, attitudes and experiences that determine the execution of a successful task.Objetivo. Identificar las aproximaciones teóricas sobre competencias laborales comprendidas en el periodo 2010-2021. Metodología. Esta investigación es un artículo de revisión que utiliza como herramienta el Protocolo PRISMA 2009, por medio del cual se hizo posible seleccionar los artículos de acuerdo a ciertos criterios como inclusión y exclusión. Resultados. El estudio realizado acerca de las competencias laborales demostró que durante el periodo 2010-2021, el número de artículos de revisión se incrementó considerablemente, de los cuales se tomó en cuenta 35 artículos que pasaron por diversos filtros. Conclusión. Se logró apreciar la existencia de una mayor elaboración de investigaciones entre los años 2019 y 2020, otorgando mayor énfasis a esta variable, puesto que el constructo de competencias laborales revela todo un conjunto de conocimientos, habilidades, actitudes y experiencias que determinan la ejecución de una tarea exitosa
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