Oral tryptophan activates duodenal aryl hydrocarbon receptor in healthy subjects: a crossover randomized controlled trial.

Tryptophan is an essential amino acid transformed by host and gut microbial enzymes into metabolites that regulate mucosal homeostasis through aryl hydrocarbon receptor (AhR) activation. Alteration of tryptophan metabolism has been associated with chronic inflammation; however, whether tryptophan supplementation affects the metabolite repertoire and AhR activation under physiological conditions in humans is unknown. We performed a randomized, double blind, placebo-controlled, crossover study in 20 healthy volunteers.

Gluten-Free Diet Reduces Symptoms, Particularly Diarrhea, in Patients With Irritable Bowel Syndrome and Antigliadin IgG.

Background & Aims: Many patients with irritable bowel syndrome (IBS) perceive that their symptoms are triggered by wheat-containing foods. We assessed symptoms and gastrointestinal transit before and after a gluten-free diet (GFD) in unselected patients with IBS and investigated biomarkers associated with symptoms.

Methods: We performed a prospective study of 50 patients with IBS (ROME III, all subtypes), with and without serologic reactivity to gluten (antigliadin IgG and IgA), and 25 healthy subjects (controls) at a university hospital in Hamilton, Ontario, Canada, between 2012 and 2016.

The Evolutionary History and Functional Divergence of Trehalase () Genes in Insects.

Trehalases () have been found in different organisms, such as bacteria, fungi, yeast, nematodes, insects, vertebrates, and plants. Their biochemical properties are extremely variable and not yet fully understood. Gene expression patterns have shown differences among insect species suggesting a potential functional diversification of trehalase enzymes during their evolution.

Genomic and Cytogenetic Localization of the Carotenoid Genes in the Aphid Genome.

Data published in the scientific literature suggests a possible link between chromosomal rearrangements involving autosomes 1 and 3 and the presence of red morphs in the peach-potato aphid Myzus persicae (Sulzer). In order to begin a study of this relationship, we analysed the genomic and chromosomal location of genes involved in carotenoid biosynthesis in M. persicae and the pea aphid, Acyrthosiphon pisum (Harris), since carotenoids are the basis of the colour in many aphid species.

Results of patch testing with fragrance mix 1, fragrance mix 2, and their ingredients, and Myroxylon pereirae and colophonium, over a 21-year period.

Background: The frequency of fragrance contact allergy has shown a fluctuating trend over the years.

Objectives: To describe the frequency of positive reactions to the baseline screening agents and fragrance mix (FM) 1 and 2 components, to determine trends of the latter over the years, and to evaluate simultaneous reactions.

Patients And Methods: This was a cross-sectional study on patch test results of 13 332 patients from January 1990 to December 2011.

Fragrance allergens in 'specific' cosmetic products.

Background: Together with preservative agents, fragrance components are the most important sensitizing culprits in cosmetic products.

Objectives: To identify the nature of the fragrance ingredients responsible for allergic contact dermatitis (ACD) from specific cosmetic products.

Methods: Between 2000 and 2009, positive patch test reactions or positive usage tests with the patients' own cosmetic products, were recorded using a standardised form.

Allergic contact dermatitis from fragrance components in specific topical pharmaceutical products in Belgium.

Objectives: To determine which topical pharmaceutical products marketed in Belgium contain fragrances and to examine the nature of the fragrance allergens in specific pharmaceutical products having caused iatrogenic contact dermatitis.

Methods: All topical pharmaceutical products marketed in Belgium, that is 3820 products, were examined as to their fragrance content as labelled. Data of 18, 960 patients investigated for contact allergy between 1978 and 2008 were retrieved from our database, including information on the nature of the topical pharmaceutical products used, the results of patch tests, and the sensitization sources.

Is a low content in atranol/chloroatranol safe in oak moss-sensitized individuals?

Background: Chloroatranol and atranol are degradation products of chloroatranorin and atranorin, respectively, and have been identified as important contact allergens in oak moss absolute (Evernia prunastri).

Objectives: To investigate whether chemically modified extracts of oak moss produce positive patch test reactions in previously sensitized subjects.

Methods: A sample of oak moss was treated by a polymer-based method to reduce the content of the two main allergens, namely atranol and chloroatranol, from 3.

Frequency of and trends in fragrance allergy over a 15-year period.

Background: The widespread use of fragrance-containing products is probably the most important reason for its high impact in allergic contact dermatitis.

Objectives: To describe the frequency of contact allergy to fragrance allergens as tested in the standard series, in relation to age, sex and lesion locations. To determine trends in frequency over the years and to study the association between positive tests observed with the different fragrance-allergy markers as well as between specific fragrance allergens and locations of the lesions.

Contact allergic reactions of the vulva: a 14-year review.

Background: In women with vulval complaints, irritant contact dermatitis is more common than allergic contact dermatitis, but secondary sensitization has to be taken into consideration since these patients often use several topical medications.

Objective: The aims of this retrospective study were to establish the prevalence of allergic contact dermatitis in patients with vulval complaints and to verify how many patients with allergic contact dermatitis suffered from a previous pathology.

Methods: We reviewed patch- and prick-test results from 92 women.