RESUMO
BACKGROUND: Patients with atopic dermatitis (AD) often report that stress aggravates their itch. However, no study has investigated if and how acute stress influences itch sensation and scratching behaviour in these patients. OBJECTIVES: We evaluated the impact of acute stress on experimentally induced cowhage itch perception and scratching behaviour in 16 healthy subjects and 15 patients with AD. METHODS: The Trier Social Stress Test (TSST) was used to induce acute stress. The itch sensation, provoked by applying cowhage to the forearms, and off-site scratching behaviour (not directed at the cowhage application site) were compared before and after performing the TSST or the control condition (watching a video of landscape scenes). RESULTS: In patients with AD, stress induced by TSST caused a significant reduction of cowhage-evoked itch but significantly increased off-site scratching behaviour. Such changes in itch perception and scratching behaviour were not observed in healthy controls. In addition, a significant positive correlation was noted between stress induced by TSST and clinical severity of eczema. CONCLUSIONS: We speculate that psychological stress increases spontaneous scratching in patients with AD, which may enhance the vicious cycle of itching and scratching, resulting in aggravation of the skin eczema. These results provide new insights on the mechanism of acute stress-related exacerbation of itch in patients with AD.
Assuntos
Dermatite Atópica/complicações , Prurido/psicologia , Estresse Psicológico/complicações , Adulto , Estudos de Casos e Controles , Dermatite Atópica/diagnóstico , Dermatite Atópica/psicologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Prurido/diagnóstico , Prurido/etiologia , Índice de Gravidade de Doença , Estresse Psicológico/psicologia , Exacerbação dos Sintomas , Adulto JovemAssuntos
Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Eritema Multiforme/induzido quimicamente , Administração Tópica , Vacina BNT162 , COVID-19/diagnóstico , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/uso terapêutico , Clobetasol/administração & dosagem , Clobetasol/uso terapêutico , Eritema Multiforme/tratamento farmacológico , Eritema Multiforme/patologia , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Pessoa de Meia-Idade , Cobertura de Condição Pré-Existente , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Exacerbação dos Sintomas , Resultado do TratamentoAssuntos
Endometriose/patologia , Dermatopatias/patologia , Feminino , Humanos , Pessoa de Meia-Idade , UmbigoAssuntos
Exantema/etiologia , Neurite Óptica/complicações , Sífilis/complicações , Adulto , Humanos , MasculinoRESUMO
A sequence-specific assignment is presented for the eight low-field paramagnetically shifted cysteinyl ligand proton NMR resonances in the 2[Fe4S4] ferredoxin from Clostridium pasteurianum. The assignment is based upon comparison of chemical shifts in 1D and 2D NMR spectra of native oxidized protein and those of three mutants. The mutant proteins G12A and G41A were designed to produce minor local structural changes (hence small chemical shift perturbations) in either cluster I (glycine 12 to alanine) or in cluster II (glycine 41 to alanine). Observed chemical shift changes in spectra of the double mutant G12,41A support the interpretation. The comparison is aided by structural models derived from the crystal structure of the related ferredoxin from Peptococcus aerogenes. Each of the eight low-field resonances is assigned to a beta-proton from a different cysteinyl ligand, and so connectivities established from previous TOCSY and HMQC data allow assignment of all 24 cysteinyl ligand protons.