28 resultados para Ancestral Mediator


Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND IL-33 enhances FcεRI-induced mediator release in human basophils without inducing degranulation itself. In contrast, studies in mice suggested that in the presence of high IgE levels, IL-33 triggers degranulation and anaphylaxis of similar severity as specific allergen. Consistent with this view, sera of atopic patients contain elevated levels of IL-33 after anaphylaxis. In this study, we determined whether IL-33 is potentially anaphylactogenic in humans with high IgE levels by regulating exocytosis independent of FcεRI cross-linking. Furthermore, we investigated whether IL-33 is released upon allergen provocation in vivo. METHODS In subjects with high serum IgE levels, we measured IL-33-induced histamine/LTC4 in vitro, CD63 translocation ex vivo, and responsiveness of mast cells in vivo by skin prick test (SPT). In asthma patients, release of IL-33 and its correlation with early (tryptase)- and late-phase markers (IL-13 levels, eosinophil numbers) of the allergic response were assessed in bronchoalveolar lavage fluids (BALFs) after allergen challenge. RESULTS IL-33 itself does not trigger basophil degranulation in vitro and ex vivo, even in subjects with high serum IgE levels, and negative SPTs demonstrate that skin mast cells do not degranulate in response to IL-33. However, in response to allergen challenge, IL-33 is rapidly released into BALFs at levels that do not correlate with other immediate- and late-phase parameters. CONCLUSION IL-33 is unlikely an independent trigger of anaphylaxis even in subjects with high IgE levels. However, the rapid release of IL-33 upon allergen provocation in vivo supports its role as a mediator of immediate allergic responses.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Aim of the study In this study we examined the effects of Taiji on perceived stress and general self-efficacy (GSE), and investigated the mediating role of a Taiji-induced GSE increase on Taiji-related reduction of perceived stress. Materials and methods 70 healthy participants were randomly allocated either to the Taiji intervention group or the waiting list control group. The intervention lasted for 12 weeks comprising two Taiji classes per week. Before, shortly after, and two months after the intervention, we assessed the degree of perceived stress and GSE in all participants by employing the Perceived Stress Scale (PSS) and the GSE-Scale. Results Compared to controls, participants of the Taiji group showed a significantly stronger decrease of perceived stress and a higher increase in GSE from pre- to post-intervention assessment (PSS: p = 0.009; GSE: p = 0.006), as well as from pre-intervention to follow-up assessment (PSS: p = 0.018; GSE: p = 0.033). A mediator analysis based on a multiple regression approach revealed that a Taiji-related increase in GSE statistically mediated the reduction in perceived stress after Taiji as compared to baseline. Post hoc testing showed that the mediating effect of GSE was significant (p = 0.043). Conclusions Our findings confirm previously reported Taiji-related stress reducing and GSE enhancing effects with GSE increase mediating Taiji related reduction of perceived stress.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose – The authors sought to explain why and how protean career attitude might influence self‐initiated expatriates' (SIEs) experiences positively. A mediation model of cultural adjustment was proposed and empirically evaluated. Design/methodology/approach – Data from 132 SIEs in Germany containing measures of protean career attitude, cultural adjustment, career satisfaction, life satisfaction, and intention to stay in the host country were analysed using path analysis with a bootstrap method. Findings – Empirical results provide support for the authors' proposed model: the positive relations between protean career attitude and the three expatriation outcomes (career satisfaction, life satisfaction and intention to stay in the host country) were mediated by positive cross‐cultural adjustment of SIEs. Research limitations/implications – All data were cross‐sectional from a single source. The sample size was small and included a large portion of Chinese participants. The study should be replicated with samples in other destination countries, and longitudinal research is suggested. Practical implications – By fostering both a protean career attitude in skilled SIE employees and their cultural adjustment, corporations and receiving countries could be able to retain this international workforce better in times of talent shortage. Originality/value – This study contributes to the scarce research on the conceptual relatedness of protean career attitude and SIEs, as well as to acknowledging the cultural diversity of the SIE population.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present study explores what mechanism might be responsible for the reported link between presence of a calling in one’s career and life satisfaction. It is proposed that vocational identity achievement acts as one important mediator of this relation and that the effects can be observed even when controlling for core self-evaluations (CSEs). The study used a short-term longitudinal design based on a sample of 269 German college students from different majors. The results confirmed the mediation model, with calling predicting vocational identity achievement 6 months later and identity serving as a stronger predictor of life satisfaction, all controlling for CSEs. However, contrary to previous research, presence of calling was not directly related to life satisfaction and even showed a negative relation when vocational identity achievement was controlled. The results are interpreted to suggest a multifaceted relation between calling and life satisfaction.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study investigated whether vocational identity achievement mediates the relation between basic personality dispositions (i.e. core self-evaluations) and career and well-being outcomes in terms of job and life satisfaction. Two studies with Swiss adolescents were conducted. Study 1 (N= 310) investigated students in eighth grade, prior to making the transition to vocational education and training (VET); it showed that vocational identity related positively to life satisfaction but that this relationship disappeared once core self-evaluations were controlled. Study 2 (N= 150) investigated students in their second year of VET; it showed that job satisfaction was unrelated to identity and self-evaluations. However, identity fully mediated the relation between self-evaluations and life satisfaction.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present study tested a possible explanation for the positive relationship between the motivation to engage in cognitive endeavors (need for cognition, NFC) and indicators of affective adjustment (e.g., higher self-esteem, lower depression) that has been demonstrated in previous studies. We suggest that dispositional self-control capacity mediates this relationship, since NFC has been found to be related to self-control capacity, and self-control capacity is crucial for adjustment. NFC, dispositional self-control capacity, self-esteem, habitual depressive mood, and tendency to respond in a socially desirable manner were measured among 150 university students via self-report. Regression analyses and Sobel tests revealed that self-control capacity was a potential mediator of the positive relationship between NFC and affective adjustment. The findings were robust in terms of social desirability.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

UNLABELLED We previously showed that close relatives of human coronavirus 229E (HCoV-229E) exist in African bats. The small sample and limited genomic characterizations have prevented further analyses so far. Here, we tested 2,087 fecal specimens from 11 bat species sampled in Ghana for HCoV-229E-related viruses by reverse transcription-PCR (RT-PCR). Only hipposiderid bats tested positive. To compare the genetic diversity of bat viruses and HCoV-229E, we tested historical isolates and diagnostic specimens sampled globally over 10 years. Bat viruses were 5- and 6-fold more diversified than HCoV-229E in the RNA-dependent RNA polymerase (RdRp) and spike genes. In phylogenetic analyses, HCoV-229E strains were monophyletic and not intermixed with animal viruses. Bat viruses formed three large clades in close and more distant sister relationships. A recently described 229E-related alpaca virus occupied an intermediate phylogenetic position between bat and human viruses. According to taxonomic criteria, human, alpaca, and bat viruses form a single CoV species showing evidence for multiple recombination events. HCoV-229E and the alpaca virus showed a major deletion in the spike S1 region compared to all bat viruses. Analyses of four full genomes from 229E-related bat CoVs revealed an eighth open reading frame (ORF8) located at the genomic 3' end. ORF8 also existed in the 229E-related alpaca virus. Reanalysis of HCoV-229E sequences showed a conserved transcription regulatory sequence preceding remnants of this ORF, suggesting its loss after acquisition of a 229E-related CoV by humans. These data suggested an evolutionary origin of 229E-related CoVs in hipposiderid bats, hypothetically with camelids as intermediate hosts preceding the establishment of HCoV-229E. IMPORTANCE The ancestral origins of major human coronaviruses (HCoVs) likely involve bat hosts. Here, we provide conclusive genetic evidence for an evolutionary origin of the common cold virus HCoV-229E in hipposiderid bats by analyzing a large sample of African bats and characterizing several bat viruses on a full-genome level. Our evolutionary analyses show that animal and human viruses are genetically closely related, can exchange genetic material, and form a single viral species. We show that the putative host switches leading to the formation of HCoV-229E were accompanied by major genomic changes, including deletions in the viral spike glycoprotein gene and loss of an open reading frame. We reanalyze a previously described genetically related alpaca virus and discuss the role of camelids as potential intermediate hosts between bat and human viruses. The evolutionary history of HCoV-229E likely shares important characteristics with that of the recently emerged highly pathogenic Middle East respiratory syndrome (MERS) coronavirus.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Numerous scholars have accumulated evidence on the positive effects that employees’ organizational justice perceptions exert on work-related outcomes such as affective commitment. However, research still lacks understanding of the underlying mechanisms connecting the two constructs. In this article we aim to narrow this gap by examining the concept of psychological ownership as a possible mediator between organizational justice perceptions and affective commitment. Investigating a sample of 619 employees, we find distributive justice to be positively related to psychological ownership, and observe psychological ownership as a full mediator of the distributive justice and affective commitment relationship. These insights offer a new explanation in understanding the justice-commitment connection, contributing to both organizational justice and psychological ownership literature and opening up ways for promising future research.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Numerous scholars have accumulated evidence on the positive effects that employees' organizational justice perceptions exert on work-related outcomes such as affective commitment. However, research still lacks understanding of the underlying mechanisms connecting the two constructs. In this article we aim to narrow this gap by examining the concept of psychological ownership as a possible mediator between organizational justice perceptions and affective commitment. Investigating a sample of 619 employees, we find distributive justice to be positively related to psychological ownership, and observe psychological ownership as a full mediator of the distributive justice and affective commitment relationship. These insights offer a new explanation in understanding the justice-commitment connection, contributing to both organizational justice and psychological ownership literature and opening up ways for promising future research