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1.
Curr Psychol ; : 1-8, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36213568

RESUMO

Understanding health belief models, and the variables that influence adherence to public health measures imposed by local governments and international health bodies, is crucial to slowing down the spread of the virus that causes COVID-19. Conspiracy theories about the virus have quickly spread on social media and have been linked to reluctance to comply with COVID-19 regulations. Personality traits such as narcissism and collective national narcissism have also been associated with the way we perceive severity and susceptibility to the disease. To examine this further, participants (N = 183) completed an online questionnaire measuring belief in COVID-19 conspiracies, trait narcissism, national narcissism, and social media usage. A model containing these variables was able to significantly predict adherence to COVID-19 preventative health behaviours, with higher levels of COVID-19 conspiracy belief, narcissism, and social media usage all contributing to reduced adherence to recommended COVID-19 health behaviours. The findings suggest conspiracy beliefs, narcissism, and social media play a key role in adherence to behaviours orientated towards stopping the spread of COVID-19. Governments and social media companies need to demonstrate greater awareness of the negative effects of conspiracy theories spread through social media, in addition to awareness of how these effects may be greater in more narcissistic individuals.

2.
Nat Commun ; 9(1): 1421, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650949

RESUMO

Acute allergic symptoms are caused by allergen-induced crosslinking of allergen-specific immunoglobulin E (IgE) bound to Fc-epsilon receptors on effector cells. Desensitization with allergen-specific immunotherapy (SIT) has been used for over a century, but the dominant protective mechanism remains unclear. One consistent observation is increased allergen-specific IgG, thought to competitively block allergen binding to IgE. Here we show that the blocking potency of the IgG response to Cat-SIT is heterogeneous. Next, using two potent, pre-selected allergen-blocking monoclonal IgG antibodies against the immunodominant cat allergen Fel d 1, we demonstrate that increasing the IgG/IgE ratio reduces the allergic response in mice and in cat-allergic patients: a single dose of blocking IgG reduces clinical symptoms in response to nasal provocation (ANCOVA, p = 0.0003), with a magnitude observed at day 8 similar to that reported with years of conventional SIT. This study suggests that simply augmenting the blocking IgG/IgE ratio may reverse allergy.


Assuntos
Anticorpos Monoclonais/farmacologia , Dessensibilização Imunológica/métodos , Glicoproteínas/imunologia , Hipersensibilidade/terapia , Imunoglobulina G/farmacologia , Receptores de IgE/imunologia , Adolescente , Adulto , Alérgenos/administração & dosagem , Alérgenos/imunologia , Alérgenos/isolamento & purificação , Pelo Animal/química , Pelo Animal/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Ligação Competitiva , Gatos , Misturas Complexas/química , Misturas Complexas/imunologia , Modelos Animais de Doenças , Feminino , Glicoproteínas/administração & dosagem , Glicoproteínas/isolamento & purificação , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/fisiopatologia , Imunoglobulina E/química , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Imunoglobulina G/biossíntese , Masculino , Camundongos , Pessoa de Meia-Idade , Ligação Proteica/efeitos dos fármacos , Receptores de IgE/química , Receptores de IgE/metabolismo
3.
J Exp Med ; 190(1): 101-11, 1999 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-10429674

RESUMO

Trichosanthin (TCS), an active protein component isolated from a traditional Chinese medicinal herb Trichosanthes kirilowii, has been shown to inhibit HIV infection and has been applied in clinical treatment of AIDS. The recent development that chemokines and chemokine receptors play important roles in HIV infection led us to investigate the possible functional interaction of TCS with chemokines and their receptors. This study demonstrated that TCS greatly enhanced both RANTES (regulated upon activation, normal T cell expressed and secreted)- and stromal cell-derived factor (SDF)-1 alpha-stimulated chemotaxis (EC50 approximately equal to 1 nM) in leukocytes (THP-1, Jurkat, and peripheral blood lymphocyte cells) and activation of pertussis toxin-sensitive G proteins (EC50 approximately equal to 20 nM). TCS also significantly augmented chemokine-stimulated activation of chemokine receptors CCR5 and CXCR4 as well as CCR1, CCR2B, CCR3, and CCR4 transiently expressed in HEK293 cells. A mutant TCS with 4,000-fold lower ribosome-inactivating activity showed similar augmentation activity as wild-type TCS. Moreover, flow cytometry demonstrated that the specific association of TCS to the cell membranes required the presence of chemokine receptors, and laser confocal microscopy reveals that TCS was colocalized with chemokine receptors on the membranes. The results from TCS-Sepharose pull-down and TCS and chemokine receptor coimmunoprecipitation and cross-linking experiments demonstrated association of TCS with CCR5. Thus, our data clearly demonstrated that TCS synergizes activities of chemokines to stimulate chemotaxis and G protein activation, and the effects of TCS are likely to be mediated through its interaction with chemokine receptors.


Assuntos
Fármacos Anti-HIV/farmacologia , Quimiocinas/farmacologia , Quimiotaxia/efeitos dos fármacos , Proteínas de Ligação ao GTP/metabolismo , Receptores de Quimiocinas/metabolismo , Tricosantina/farmacologia , Animais , Fármacos Anti-HIV/metabolismo , Linhagem Celular , Quimiocina CCL5/farmacologia , Clonagem Molecular , Imunofluorescência , Proteínas de Ligação ao GTP/efeitos dos fármacos , Humanos , Camundongos , Coelhos , Receptores CCR5/metabolismo , Tricosantina/metabolismo
4.
Neuropharmacology ; 38(7): 991-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10428417

RESUMO

The potential modulation of opioid receptor signaling by kainic acid (KA) has been investigated in neuroblastoma x glioma NG 108-15 hybrid cells and neuroblastoma SK-N-SH cells. Acute incubation of KA significantly attenuated delta opioid receptor (DOR) signaling induced by the DOR agonist [D-Pen2, D-Pen5]-enkephalin (DPDPE), as measured by activation of G proteins and inhibition of cAMP accumulation. The attenuation by KA was time- and dose-dependent and could be blocked by antagonists of kainate/AMPA receptors, suggesting possible mediation through kainate/AMPA receptors. KA attenuation of DPDPE-stimulated G protein activation was reversed by inhibitors of protein kinase C or by removal of both extracellular Ca2+ and intracellular Ca2+. In contrast, NMDA attenuation of DPDPE-stimulated G protein activation was independent of intracellular Ca2+, indicating that different mechanism(s) may underlie the modulation effect of KA and NMDA. This notion was further supported by the results that KA did not alter nociceptin/orphanin FQ-stimulated G protein activation in NG 108-15 cells but NMDA did. In addition, pretreatment of NG 108-15 cells with antagonists of kainate/AMPA receptors blocked the acute desensitization of DOR signaling. These data provide evidence that KA may be involved in the modulation of opioid receptor signal transduction.


Assuntos
Cálcio/metabolismo , Agonistas de Aminoácidos Excitatórios/farmacologia , Ácido Caínico/farmacologia , Neurônios/efeitos dos fármacos , Proteína Quinase C/metabolismo , Receptores Opioides delta/metabolismo , Animais , D-Penicilina (2,5)-Encefalina , Encefalinas/farmacologia , Proteínas de Ligação ao GTP/metabolismo , Camundongos , Neurônios/citologia , Neurônios/enzimologia , Neurônios/metabolismo , Receptores de AMPA/efeitos dos fármacos , Receptores de AMPA/metabolismo , Receptores Opioides/efeitos dos fármacos , Receptores Opioides/metabolismo , Receptores Opioides delta/agonistas , Receptores Opioides delta/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Receptor de Nociceptina
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