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1.
J Exp Child Psychol ; 244: 105949, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38705097

RESUMEN

Parents' judgments about their children's level of interest in different science topics may affect the science-learning opportunities they provide their children. However, little is known about how parents judge these interests. We used the truth and bias model of judgment of West and Kenny (Psychological Review [2011], Vol. 118, pp. 357-378) to examine factors that may affect parents' judgments of their children's science interests such as the truth (children's self-reported interest) and potential sources of parental bias. We also investigated whether several individual difference measures moderated the effect of truth or bias on judgments. Children (N = 139, ages 7-11 years) rated their level of interest in five science and five non-science topics. Separately, parents (N = 139) judged their children's interest in the same topics. Overall, parents accurately judged their children's science interests, but we also found evidence of some forms of bias, namely that parents generally under-estimated their children's science interests. In addition, parents' personal science attitudes were related to judgments of science interests, such that parents more favorable of science tended to rate their children's interest in science topics higher than parents with a less favorable view. We did not find evidence that individual differences among parents moderated the effect of truth or bias on judgments; however, parents were more accurate at judging the non-science interests of older children than younger children. Parents should be aware that they may be under-estimating their children's interest in science topics and that their personal attitudes about science may be influencing their judgments of their children's science interests.


Asunto(s)
Juicio , Padres , Ciencia , Humanos , Niño , Femenino , Masculino , Padres/psicología , Adulto , Sesgo , Actitud , Relaciones Padres-Hijo
2.
J Virol ; 88(11): 6031-46, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24623433

RESUMEN

UNLABELLED: The type I interferon-inducible factor tetherin retains virus particles on the surfaces of cells infected with vpu-deficient human immunodeficiency virus type 1 (HIV-1). While this mechanism inhibits cell-free viral spread, the immunological implications of tethered virus have not been investigated. We found that surface tetherin expression increased the antibody opsonization of vpu-deficient HIV-infected cells. The absence of Vpu also stimulated NK cell-activating FcγRIIIa signaling and enhanced NK cell degranulation and NK cell-mediated antibody-dependent cellular cytotoxicity (ADCC). The deletion of vpu in HIV-1-infected primary CD4(+) T cells enhanced the levels of antibody binding and Fc receptor signaling mediated by HIV-positive-patient-derived antibodies. The magnitudes of antibody binding and Fc signaling were both highly correlated to the levels of tetherin on the surfaces of infected primary CD4 T cells. The affinity of antibody binding to FcγRIIIa was also found to be critical in mediating efficient Fc activation. These studies implicate Vpu antagonism of tetherin as an ADCC evasion mechanism that prevents antibody-mediated clearance of virally infected cells. IMPORTANCE: The ability of the HIV-1 accessory factor to antagonize tetherin has been considered to primarily function by limiting the spread of virus by preventing the release of cell-free virus. This study supports the hypothesis that a major function of Vpu is to decrease the recognition of infected cells by anti-HIV antibodies at the cell surface, thereby reducing recognition by antibody-dependent clearance by natural killer cells.


Asunto(s)
Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Antígenos CD/inmunología , Proteínas del Virus de la Inmunodeficiencia Humana/inmunología , Células Asesinas Naturales/inmunología , Receptores de IgG/inmunología , Transducción de Señal/inmunología , Proteínas Reguladoras y Accesorias Virales/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Citometría de Flujo , Proteínas Ligadas a GPI/antagonistas & inhibidores , Proteínas Ligadas a GPI/inmunología , Humanos , Células Jurkat , Proteína 1 de la Membrana Asociada a los Lisosomas/inmunología , Proteínas Opsoninas/inmunología , Receptores de IgG/metabolismo
3.
Dev Psychol ; 60(1): 1-16, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37956037

RESUMEN

Two studies examined the process and aftermath of coming to disbelieve in the myth of Santa Claus. In Study 1, 48 children ages 6-15 answered questions about how they discovered Santa was not real and how the discovery made them feel, and 44 of their parents shared their perspectives and how they promoted Santa. In Study 2, 383 adults reflected on their experiences shifting to disbelief in Santa Claus. In both studies, the average age of disbelief was around 8, but with significant variability. Most participants reported testimony from others contributed to their disbelief, and some reported skepticism as a result of either experience (e.g., observation) or logical reasoning. About a third of children and half of adults reported some negative emotions upon discovering the truth. Higher levels of parental Santa promotion were associated with experiencing some negative emotions upon discovering the truth in both studies. Additionally, adults who reported feeling only negative emotions tended to be older when they discovered the truth, more likely to have reported learning the truth abruptly, and more likely to have reported learning the truth through testimony. That said, experiences of negative emotions were generally short-lived, and the vast majority of both children and adults reported they would celebrate Santa with their own children or were already doing so. Implications of these findings for how to approach children's transition to skepticism regarding Santa are discussed, including timing, the role of parents, and popular notions of discovery for children's trust toward their parents. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Aprendizaje , Padres , Niño , Adulto , Humanos , Padres/psicología , Emociones
4.
Dev Psychol ; 58(3): 417-424, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34928632

RESUMEN

When children ask questions about science, parents use a variety of strategies to answer them, including providing accurate information, connecting to prior knowledge, or simply saying "I do not know." This study examines the factors underlying individual differences in parental explanatory characteristics. Parents (N = 148; Mage = 38; 84% female, 16% male; 58% with White American children; 67% having completed college; 49% with household income over $75,000) of children ages 7 to 10 answered eight questions about biology as if they were responding to their child. They also completed three measures of different aspects of reasoning and values: the Picture Vocabulary Test (PVT) to measure verbal intelligence (Gershon et al., 2013), the Cognitive Reflection Test (CRT; Toplak et al., 2014), which measures the tendency to override intuitive but incorrect responses to engage in reflective thinking, and the Authoritarianism Scale (Feldman & Stenner, 1997), which measures a parent's preference for encouraging obedience toward authority figures over encouraging their child's autonomy. Our findings support that different factors are associated with different explanatory characteristics. Parents high in reflective thinking tend to provide more connections to other knowledge in their explanations, while parents high in authoritarianism tend to provide fewer references to uncertainty and how to manage it. Implications for effective parent-child communication and children's scientific understanding will be discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Autoritarismo , Padres , Adulto , Niño , Cognición , Femenino , Humanos , Masculino , Relaciones Padres-Hijo , Padres/psicología , Solución de Problemas
5.
JCI Insight ; 5(2)2020 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-31996483

RESUMEN

In the RV144 HIV-1 phase III trial, vaccine efficacy directly correlated with the magnitude of the variable region 2-specific (V2-specific) IgG antibody response, and in the presence of low plasma IgA levels, with the magnitude of plasma antibody-dependent cellular cytotoxicity. Reenrollment of RV144 vaccinees in the RV305 trial offered the opportunity to define the function, maturation, and persistence of vaccine-induced V2-specific and other mAb responses after boosting. We show that the RV144 vaccine regimen induced persistent V2 and other HIV-1 envelope-specific memory B cell clonal lineages that could be identified throughout the approximately 11-year vaccination period. Subsequent boosts increased somatic hypermutation, a critical requirement for antibody affinity maturation. Characterization of 22 vaccine-induced V2-specific mAbs with epitope specificities distinct from previously characterized RV144 V2-specific mAbs CH58 and CH59 found increased in vitro antibody-mediated effector functions. Thus, when inducing non-neutralizing antibodies, one method by which to improve HIV-1 vaccine efficacy may be through late boosting to diversify the V2-specific response to increase the breadth of antibody-mediated anti-HIV-1 effector functions.


Asunto(s)
Vacunas contra el SIDA/inmunología , Anticuerpos Anti-VIH/inmunología , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Vacunas contra el SIDA/química , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos , Ensayos Clínicos como Asunto , Epítopos/genética , Epítopos/inmunología , Anticuerpos Anti-VIH/química , Anticuerpos Anti-VIH/genética , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , VIH-1/inmunología , Humanos , Inmunización Secundaria , Modelos Moleculares , Mutación , Conformación Proteica , Vacunas Virales , Difracción de Rayos X , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología
7.
Nat Med ; 24(4): 408-416, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29554083

RESUMEN

Development of a highly effective vaccine or antibodies for the prevention and ultimately elimination of malaria is urgently needed. Here we report the isolation of a number of human monoclonal antibodies directed against the Plasmodium falciparum (Pf) circumsporozoite protein (PfCSP) from several subjects immunized with an attenuated Pf whole-sporozoite (SPZ) vaccine (Sanaria PfSPZ Vaccine). Passive transfer of one of these antibodies, monoclonal antibody CIS43, conferred high-level, sterile protection in two different mouse models of malaria infection. The affinity and stoichiometry of CIS43 binding to PfCSP indicate that there are two sequential multivalent binding events encompassing the repeat domain. The first binding event is to a unique 'junctional' epitope positioned between the N terminus and the central repeat domain of PfCSP. Moreover, CIS43 prevented proteolytic cleavage of PfCSP on PfSPZ. Analysis of crystal structures of the CIS43 antigen-binding fragment in complex with the junctional epitope determined the molecular interactions of binding, revealed the epitope's conformational flexibility and defined Asn-Pro-Asn (NPN) as the structural repeat motif. The demonstration that CIS43 is highly effective for passive prevention of malaria has potential application for use in travelers, military personnel and elimination campaigns and identifies a new and conserved site of vulnerability on PfCSP for next-generation rational vaccine design.


Asunto(s)
Vacunas contra la Malaria/inmunología , Malaria/inmunología , Parásitos/inmunología , Proteínas Protozoarias/química , Animales , Anticuerpos Monoclonales , Anticuerpos Antiprotozoarios/inmunología , Humanos , Ratones , Plasmodium falciparum/inmunología
8.
Sci Transl Med ; 9(381)2017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28298420

RESUMEN

A preventive HIV-1 vaccine should induce HIV-1-specific broadly neutralizing antibodies (bnAbs). However, bnAbs generally require high levels of somatic hypermutation (SHM) to acquire breadth, and current vaccine strategies have not been successful in inducing bnAbs. Because bnAbs directed against a glycosylated site adjacent to the third variable loop (V3) of the HIV-1 envelope protein require limited SHM, the V3-glycan epitope is an attractive vaccine target. By studying the cooperation among multiple V3-glycan B cell lineages and their coevolution with autologous virus throughout 5 years of infection, we identify key events in the ontogeny of a V3-glycan bnAb. Two autologous neutralizing antibody lineages selected for virus escape mutations and consequently allowed initiation and affinity maturation of a V3-glycan bnAb lineage. The nucleotide substitution required to initiate the bnAb lineage occurred at a low-probability site for activation-induced cytidine deaminase activity. Cooperation of B cell lineages and an improbable mutation critical for bnAb activity defined the necessary events leading to breadth in this V3-glycan bnAb lineage. These findings may, in part, explain why initiation of V3-glycan bnAbs is rare, and suggest an immunization strategy for inducing similar V3-glycan bnAbs.


Asunto(s)
Anticuerpos Neutralizantes/metabolismo , VIH-1/inmunología , Polisacáridos/metabolismo , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/genética , Cristalografía por Rayos X , Humanos , Masculino , Mutación/genética , Pruebas de Neutralización , Filogenia , Unión Proteica , Productos del Gen env del Virus de la Inmunodeficiencia Humana/metabolismo
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