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1.
Clin Exp Allergy ; 48(9): 1206-1213, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29904971

RESUMO

BACKGROUND: The role of sensitization to commercially available allergens of English walnut (Juglans regia) Jug r 1, 2 and 3 in walnut allergy has been previously investigated in walnut allergic adults and was unable to explain all cases of walnut allergy. OBJECTIVES: Identify recognized walnut allergens, other than the ones previously investigated (Jug r 1-3), in walnut allergic adults and determine the sensitization frequency and diagnostic value. METHODS: Three different in-house walnut extracts were prepared and analysed on SDS-PAGE blots to identify allergenic walnut proteins. Immunoblots and immunoprecipitation, followed by LC-MS analysis, were performed to screen for, and confirm, IgE binding to walnut allergens in selected walnut allergic adults. In a cohort of 55 walnut challenged adults, including 33 allergic and 22 tolerant, sensitization to native and recombinant walnut allergen Jug r 4 was assessed using immunoblotting and immuno-line blot (EUROLINE), respectively. RESULTS: Screening of sera of 8 walnut allergic adults identified Jug r 4 as an allergen in our population. In the total cohort of 55 subjects, 5 were positive for Jug r 4 on immunoblot and 10 on EUROLINE. All but one EUROLINE positive subject had a positive food challenge (sensitivity 27%, specificity 95%, PPV 90%, NPV 47%). All 5 subjects positive on immunoblot were also positive on EUROLINE. LC-MS analysis showed a lack of Jug r 4 in the ImmunoCAP extract. Co-sensitization to other 11S albumins (eg hazelnut Cor a 9) was common in Jug r 4 sensitized subjects, potentially due to cross-reactivity. CONCLUSIONS: Walnut 11S globulin Jug r 4 is a relevant minor allergen, recognized by 27% of walnut allergic adults. It has a high positive predictive value of 90% for walnut allergy. Specific IgE against Jug r 4 occurred mostly with concomitant sensitization to other walnut components, mainly Jug r 1.


Assuntos
Antígenos de Plantas/imunologia , Juglans/efeitos adversos , Hipersensibilidade a Noz/imunologia , Proteínas de Plantas/imunologia , Adulto , Antígenos de Plantas/química , Antígenos de Plantas/isolamento & purificação , Cromatografia Líquida , Reações Cruzadas/imunologia , Feminino , Humanos , Imunoensaio , Imunoglobulina E/imunologia , Juglans/química , Masculino , Espectrometria de Massas , Hipersensibilidade a Noz/diagnóstico , Extratos Vegetais/química , Extratos Vegetais/imunologia , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Sensibilidade e Especificidade , Testes Cutâneos , Adulto Jovem
2.
Food Chem Toxicol ; 189: 114766, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38810945

RESUMO

The growing world population, changing dietary habits, and increasing pressure on agricultural resources are drivers for the development of novel foods (including new protein sources as well as existing protein sources that are produced or used in an alternative way or in a different concentration). These changes, coupled with consumer inclination to adopt new dietary trends, may heighten the intake of unfamiliar proteins, or escalate consumption of specific ones, potentially amplifying the prevalence of known and undiscovered food allergies. Assessing the allergenicity of novel or modified protein-based foods encounters several challenges, including uncertainty surrounding acceptable risks and assessment criteria for determining safety. Moreover, the available methodological tools for gathering supportive data exhibit significant gaps. This paper synthesises these challenges, addressing the varied interpretations of "safe" across jurisdictions and societal attitudes towards allergenic risk. It proposes a comprehensive two-part framework for allergenicity assessment: the first part emphasises systematic consideration of knowledge and data requirements, while the second part proposes the application of a generic assessment approach, integrating a Threshold of Allergological Concern. This combined framework highlights areas that require attention to bridge knowledge and data gaps, and it delineates research priorities for its development and implementation.


Assuntos
Alérgenos , Hipersensibilidade Alimentar , Humanos , Hipersensibilidade Alimentar/imunologia , Alérgenos/imunologia , Alérgenos/química , Proteínas Alimentares/imunologia , Medição de Risco , Animais , Alimentos Geneticamente Modificados , Ingredientes de Alimentos/análise
3.
Drug Metab Dispos ; 41(3): 592-601, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23248200

RESUMO

Organic anion-transporting polypeptide 1B1 (OATP1B1) is an important hepatic uptake transporter, of which the polymorphic variant OATP1B1*15 (Asn130Asp and Val174Ala) has been associated with decreased transport activity. Rosuvastatin is an OATP1B1 substrate and often concomitantly prescribed with oral antidiabetics in the clinic. The aim of this study was to investigate possible drug-drug interactions between these drugs at the level of OATP1B1 and OATP1B1*15. We generated human embryonic kidney (HEK)293 cells stably overexpressing OATP1B1 or OATP1B1*15 that showed similar protein expression levels of OATP1B1 and OATP1B1*15 at the cell membrane as measured by liquid chromatography-tandem mass spectrometry. In HEK-OATP1B1*15 cells, the V(max) for OATP1B1-mediated transport of E(2)17ß-G (estradiol 17ß-d-glucuronide) was decreased >60%, whereas K(m) values (Michaelis constant) were comparable. Uptake of rosuvastatin in HEK-OATP1B1 cells (K(m) 13.1 ± 0.43 µM) was nearly absent in HEK-OATP1B1*15 cells. Interestingly, several oral antidiabetics (glyburide, glimepiride, troglitazone, pioglitazone, glipizide, gliclazide, and tolbutamide), but not metformin, were identified as significant inhibitors of the OATP1B1-mediated transport of rosuvastatin. The IC(50) values for inhibition of E(2)17ß-G uptake were similar between OATP1B1 and OATP1B1*15. In conclusion, these studies indicate that several oral antidiabetic drugs affect the OATP1B1-mediated uptake of rosuvastatin in vitro. The next step will be to translate these data to the clinical situation, as it remains to be established whether the studied oral antidiabetics indeed affect the clinical pharmacokinetic profile of rosuvastatin in patients.


Assuntos
Fluorbenzenos/metabolismo , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Pirimidinas/metabolismo , Sulfonamidas/metabolismo , Administração Oral , Cromatografia Líquida , Relação Dose-Resposta a Droga , Interações Medicamentosas , Estradiol/análogos & derivados , Estradiol/metabolismo , Células HEK293 , Humanos , Hipoglicemiantes/administração & dosagem , Cinética , Transportador 1 de Ânion Orgânico Específico do Fígado , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Rosuvastatina Cálcica , Espectrometria de Massas em Tandem , Transfecção
4.
Allergy ; 68(8): 983-93, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23889537

RESUMO

BACKGROUND: Allergenicity of foods can be influenced by processing. Tree nuts are an important source of nutrition and increasingly consumed; however, processing methods are quite variable and data are currently lacking on the effects of processing on allergenicity. OBJECTIVE: To perform a systematic literature review on the effects of food processing on the allergenicity of tree nuts. METHODS: A systematic literature search of PubMed and Embase databases was performed, with screening of references, related articles and citations. Studies were included if they assessed the allergenicity or immunogenicity of processed nuts. RESULTS: The search resulted in 32 articles suitable for analysis. Clinical studies indicate that roasting reduces the allergenicity of hazelnut in individuals with a birch pollen allergy and reactivity to raw hazelnut. Thermal processing may reduce the allergenicity of the PR-10 protein in hazelnut and almond in vitro. The majority of the in vitro studies investigating the allergenicity of nonspecific lipid transfer proteins (nsLTPs) and seed storage proteins in hazelnut, almond, cashew nut, Brazil nut, walnut, pecan nut and pistachio nut show heat stability towards different thermal processing methods. CONCLUSION: Thermal processing may reduce allergenicity of PR-10 proteins in hazelnut and almond, in contrast to nsLTPs and seed storage proteins. This has important implications for source materials used for IgE testing and food challenges and diet advice.


Assuntos
Alérgenos/imunologia , Manipulação de Alimentos/métodos , Temperatura Alta , Hipersensibilidade a Noz/imunologia , Árvores/imunologia , Proteínas de Transporte/imunologia , Humanos , Pólen/imunologia
5.
J Vet Pharmacol Ther ; 28(6): 531-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16343285

RESUMO

In this study the anti-inflammatory properties of zilpaterol, a beta2-adrenergic receptor (AR) agonist specifically developed as a growth promoter in cattle were investigated. Although zilpaterol has a different structure compared with the beta2-AR agonists known to date, it was noted that it was able to bind to both the beta2-AR (Ki = 1.1 x 10(-6)) and the beta1-AR (Ki = 1.0 x 10(-5)). Using lipopolysaccharide (LPS)-exposed U937 macrophages, the production of cyclic adenosine-3',5'-cyclic monophosphate (cAMP) and tumor necrosis factor alpha (TNF-alpha) were investigated. Zilpaterol inhibited TNF-alpha release and induced intracellular cAMP levels in a dose-dependent manner. The inhibition of TNF-alpha release and induction of cAMP production was mainly mediated via the beta2-AR, as indicated by addition of beta1- and beta2-specific antagonists. The effects of zilpaterol were investigated in LPS-treated male Wistar rats after pretreatment with zilpaterol. Zilpaterol dosed at 500 microg/kg body weight reduced the TNF-alpha plasma levels. In conclusion, zilpaterol is a beta2-adrenergic agonist and an inhibitor of TNF-alpha production induced by LPS both in vivo and in vitro.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Fatores Imunológicos/farmacologia , Compostos de Trimetilsilil/farmacologia , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Agonistas Adrenérgicos beta/administração & dosagem , Animais , Bovinos , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Escherichia coli , Humanos , Fatores Imunológicos/administração & dosagem , Lipopolissacarídeos , Ativação de Macrófagos/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Compostos de Trimetilsilil/administração & dosagem , Fator de Necrose Tumoral alfa/metabolismo , Células U937/efeitos dos fármacos , Células U937/metabolismo
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