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1.
Allergy ; 77(6): 1797-1814, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34606106

RESUMO

BACKGROUND: Allergic asthma (AA) and allergic rhinoconjunctivitis (ARC) are common comorbid environmentally triggered diseases. We hypothesized that severe AA/ARC reflects a maladaptive or unrestrained response to ubiquitous aeroallergens. METHODS: We performed provocation studies wherein six separate cohorts of persons (total n = 217) with ARC, with or without AA, were challenged once or more with fixed concentrations of seasonal or perennial aeroallergens in an aeroallergen challenge chamber (ACC). RESULTS: Aeroallergen challenges elicited fully or partially restrained vs. unrestrained evoked symptom responsiveness, corresponding to the resilient and adaptive vs. maladaptive AA/ARC phenotypes, respectively. The maladaptive phenotype was evoked more commonly during challenge with a non-endemic versus endemic seasonal aeroallergen. In an AA cohort, symptom responses evoked after house dust mite (HDM) challenges vs. recorded in the natural environment were more accurate and precise predictors of asthma severity and control, lung function (FEV1), and mechanistic correlates of maladaptation. Correlates included elevated levels of peripheral blood CD4+ and CD8+ T-cells, eosinophils, and T-cell activation, as well as gene expression proxies for ineffectual epithelial injury/repair responses. Evoked symptom severity after HDM challenge appeared to be more closely related to levels of CD4+ and CD8+ T-cells than eosinophils, neutrophils, or HDM-specific IgE. CONCLUSIONS: Provocation studies support the concept that resilience, adaptation, and maladaptation to environmental disease triggers calibrate AA/ARC severity. Despite the ubiquity of aeroallergens, in response to these disease triggers in controlled settings (ie, ACC), most atopic persons manifest the resilient or adaptive phenotype. Thus, ARC/AA disease progression may reflect the failure to preserve the resilient or adaptive phenotype. The triangulation of CD8+ T-cell activation, airway epithelial injury/repair processes and maladaptation in mediating AA disease severity needs more investigation.


Assuntos
Asma , Conjuntivite Alérgica , Conjuntivite , Alérgenos , Animais , Asma/diagnóstico , Asma/etiologia , Conjuntivite Alérgica/diagnóstico , Eosinófilos , Humanos , Pyroglyphidae
2.
Allergy Asthma Proc ; 43(2): 116-123, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35317888

RESUMO

Background: Oak and birch pollens are strongly cross-reactive. It is unknown how robust this cross-reactivity is in patients without natural exposure to pollen of both trees. We assessed the symptom response to birch pollen in subjects with skin-prick test (SPT) results positive to oak and birch but only naturally exposed to oak by using an allergen challenge chamber. Methods: The subjects with SPT results positive to oak and birch had their serum-specific immunoglobulin E (ssIgE) to oak and birch antigens measured. Residential historical data were obtained. The subjects were exposed to birch pollen (3500 ± 700 grains/m³) in two consecutive 3-hour challenges. Symptoms were recorded at baseline and 30-minute intervals. Results: Twenty-four subjects, 12 men; ages 20-58 years, completed the study. Sixteen subjects (66.7%) responded with high Total Symptom Scores (TSS) ≥10 of a maximum 21. Twelve subjects (50%) had ssIgE values ≥0.70 kU/L to oak, 10 of whom had ssIgE values ≥0.70 kU/L to birch. These 10 subjects had a significantly higher maximum TSS than the rest. Also, 15 subjects without a previous natural exposure to birch pollen responded with TSS equivalent to the 9 subjects with previous exposure. Conclusion: Virginia live oak ssIgE levels of patients allergic to oak and birch correlated with the symptom response to birch pollen exposure, even without previous natural exposure to birch. The subjects naive to birch pollen responded to birch pollen exposure with symptoms comparable with both those with previous sustained exposure and also those who resided in endemic areas, as reported by other researchers.


Assuntos
Hipersensibilidade , Quercus , Adulto , Alérgenos , Betula , Feminino , Humanos , Hipersensibilidade/diagnóstico , Imunoglobulina E , Masculino , Pessoa de Meia-Idade , Pólen , Adulto Jovem
3.
J Allergy Clin Immunol ; 148(2): 533-549, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33493557

RESUMO

BACKGROUND: Signifying the 2-compartments/1-disease paradigm, allergic rhinoconjunctivitis (ARC) and asthma (AA) are prevalent, comorbid conditions triggered by environmental factors (eg, house dust mites [HDMs]). However, despite the ubiquity of triggers, progression to severe ARC/AA is infrequent, suggesting either resilience or adaptation. OBJECTIVE: We sought to determine whether ARC/AA severity relates to maladaptive responses to disease triggers. METHODS: Adults with HDM-associated ARC were challenged repetitively with HDMs in an aeroallergen challenge chamber. Mechanistic traits associated with disease severity were identified. RESULTS: HDM challenges evoked maladaptive (persistently higher ARC symptoms), adaptive (progressive symptom reduction), and resilient (resistance to symptom induction) phenotypes. Symptom severity in the natural environment was an imprecise correlate of the phenotypes. Nasal airway traits, defined by low inflammation-effectual epithelial integrity, moderate inflammation-effectual epithelial integrity, and higher inflammation-ineffectual epithelial integrity, were hallmarks of the resilient, adaptive, and maladaptive evoked phenotypes, respectively. Highlighting a crosstalk mechanism, peripheral blood inflammatory tone calibrated these traits: ineffectual epithelial integrity associated with CD8+ T cells, whereas airway inflammation associated with both CD8+ T cells and eosinophils. Hallmark peripheral blood maladaptive traits were increased natural killer and CD8+ T cells, lower CD4+ mucosal-associated invariant T cells, and deficiencies along the TLR-IRF-IFN antiviral pathway. Maladaptive traits tracking HDM-associated ARC also contributed to AA risk and severity models. CONCLUSIONS: Repetitive challenges with HDMs revealed that maladaptation to disease triggers may underpin ARC/AA disease severity. A combinatorial therapeutic approach may involve reversal of loss-of-beneficial-function traits (ineffectual epithelial integrity, TLR-IRF-IFN deficiencies), mitigation of gain-of-adverse-function traits (inflammation), and blocking of a detrimental crosstalk between the peripheral blood and airway compartments.


Assuntos
Alérgenos/toxicidade , Asma/imunologia , Eosinófilos/imunologia , Linfócitos/imunologia , Pyroglyphidae , Mucosa Respiratória/imunologia , Adulto , Alérgenos/imunologia , Animais , Asma/patologia , Eosinófilos/patologia , Feminino , Humanos , Inflamação/imunologia , Inflamação/patologia , Linfócitos/patologia , Masculino
4.
Ann Allergy Asthma Immunol ; 123(2): 201-207, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31042573

RESUMO

BACKGROUND: A variety of antigens have been identified as causative of hypersensitivity pneumonitis (HP), which is characterized by inflammation to the lung parenchyma that is induced by exposure. Goose and duck down (GDD) bedding is often overlooked by physicians as a potential cause, yet the use of GDD has markedly increased in recent years, paralleling an increased frequency of reports of GDD-induced HP. OBJECTIVE: To determine the frequency of GDD as the causative antigen in patients with HP who use bedding that contains GDD. METHODS: Patients referred with a working diagnosis of HP underwent a detailed environmental history. Those who were using GDD were asked to remove it as an avoidance procedure. Signs, symptoms, spirometry, and inflammatory markers were followed up at weekly intervals for up to 1 month to determine the effect of remediation. RESULTS: Eighty patients with HP were seen during an 8-year period. Thirty-two patients (40%) were using GDD bedding. Of these 32 patients, 12 (37.5% of those exposed and 15% of the total HP population experienced remission (or nonprogression) of disease by simply avoiding GDD bedding. Eleven (92%) of these 12 patients were female. In patients with GDD-induced HP, lung biopsy patterns were varied. CONCLUSION: Approximately one-third of patients with HP, who slept with GDD, had persistent improvement or remission with simple avoidance. The higher incidence of GDD-induced HP in females may be hormonal and/or sociocultural related. Lung biopsy findings were across the spectrum of histopathologic patterns. Avoidance-challenge techniques were effective in confirming diagnoses and causation and mitigating the need for additional remediation.


Assuntos
Alveolite Alérgica Extrínseca/epidemiologia , Alveolite Alérgica Extrínseca/imunologia , Plumas/imunologia , Pulmão/patologia , Tecido Parenquimatoso/patologia , Idoso , Idoso de 80 Anos ou mais , Alveolite Alérgica Extrínseca/diagnóstico , Animais , Patos , Feminino , Gansos , Humanos , Masculino , Pessoa de Meia-Idade , Espirometria
6.
CBE Life Sci Educ ; 17(1)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29326102

RESUMO

Many efforts to improve science teaching in higher education focus on a few faculty members at an institution at a time, with limited published evidence on attempts to engage faculty across entire departments. We created a long-term, department-wide collaborative professional development program, Biology Faculty Explorations in Scientific Teaching (Biology FEST). Across 3 years of Biology FEST, 89% of the department's faculty completed a weeklong scientific teaching institute, and 83% of eligible instructors participated in additional semester-long follow-up programs. A semester after institute completion, the majority of Biology FEST alumni reported adding active learning to their courses. These instructor self-reports were corroborated by audio analysis of classroom noise and surveys of students in biology courses on the frequency of active-learning techniques used in classes taught by Biology FEST alumni and nonalumni. Three years after Biology FEST launched, faculty participants overwhelmingly reported that their teaching was positively affected. Unexpectedly, most respondents also believed that they had improved relationships with departmental colleagues and felt a greater sense of belonging to the department. Overall, our results indicate that biology department-wide collaborative efforts to develop scientific teaching skills can indeed attract large numbers of faculty, spark widespread change in teaching practices, and improve departmental relations.


Assuntos
Biologia/educação , Desenvolvimento de Programas , Ensino , Docentes , Objetivos , Humanos , Motivação , Aprendizagem Baseada em Problemas , Estudantes , Inquéritos e Questionários
8.
FEMS Yeast Res ; 6(2): 205-17, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16487344

RESUMO

The role of phosphatidylcholine turnover during hypersaline stress is investigated in Saccharomyces cerevisiae. In the wild-type strain, 2180-1A hypersaline stress induced the rapid turnover of phosphatidylcholine, a major membrane lipid. Yeast cells were grown in the presence of [14C]-choline to label phosphatidylcholine. Upon shifting the cells to medium with 0.8 M NaCl, phosphatidylcholine levels were diminished by c. 30% within 20 min to yield glycerophosphocholine, a methylamine osmoprotectant that has been previously identified in renal cells. High-performance liquid chromatography studies showed that osmotically mediated glycerophosphocholine production was enhanced if 10 mM choline was added as a supplement to synthetic dextrose medium with 1.6 M NaCl, but glycine betaine was not detected. Enhanced glycerophosphocholine production also correlated with improved growth in media containing 1.6 M NaCl and choline. Enhanced growth is specific to methylamines: salt-stressed cells supplemented with 10 mM choline or glycine betaine showed enhanced growth relative to unsupplemented control cultures, but other additives had no effect on growth or adversely affected it. Nutritional effects are ruled out because yeast cannot use choline or glycine betaine as carbon or nitrogen sources in normal or high-salt medium. Finally, enhanced growth in hypersaline media with choline or glycine betaine is dependent on the choline permease Hnm1. These results in yeast highlight a similarity with mammalian renal cells, namely that phosphatidylcholine turnover contributes to osmotic adaptation via synthesis of the osmoprotectant glycerophosphocholine.


Assuntos
Metilaminas/metabolismo , Fosfatidilcolinas/metabolismo , Saccharomyces cerevisiae/fisiologia , Betaína , Meios de Cultura , Proteínas de Membrana Transportadoras/fisiologia , Metilaminas/análise , Pressão Osmótica , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo
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