Respiratory Allergy to Conifers

The conifers, from the latin meaning “cone carrier,” include about 650 species distributed in seven families. They are found all over the world, and the most known conifers are the cypresses, the junipers, the yews, the larches, the firs, or the pines. The most allergenic pollen is emitted by the Cupressaceae/Taxaceae family with mainly five different genera: Cupressus, Hesperocyparis, Juniperus, Cryptomeria, and Chamaecyparis. The symptomatic period starts in November and ends in April. In Mediterranean areas, Cupressus sempervirens is the most common pollinating species. Five main cypress allergens have been thoroughly described. Depending on the geographic area and the studied population, the prevalence of cypress allergy in the general population ranges from 0.6% to 3%, and 9–65% of outpatients consulting an allergist are sensitized to cypress pollen. This prevalence is increasing likely to be due to the modifications of the environment. Rhinitis is the most prevalent clinical symptom, while conjunctivitis is the most disabling. Clear-cut improvements of the quality of life are observed upon an effective and safe specific immunotherapy. Associations with food allergy based on molecular allergen cross-reactivities were described resulting in sometimes severe symptoms. Pollens from Pinaceae family, especially pines or firs, although abundant, do not demonstrate a significant clinical impact

High IgE sensitization to maize and rice pollen in the highlands of Madagascar

Introduction: maize and rice are two crops constituting the main food supply in many under-developed and developing countries. Despite the large area devoted to the culture, the sensitization to the pollen from these plants is reported to be low and often considered as an occupational allergy. Methods: sixty five Malagasy pollen allergic patients were clinically and immunochemically investigated with regard to maize and rice pollen allergens. Pollen extracts were electrophoretically separated in 1 and 2 dimensions and IgE and IgG reactivities detected upon immunoblotting. Results: when exploring the sensitization profile of Malagasy allergic patients to maize and rice pollen, it appears that a high proportion of these patients consulting during grass pollinating season were sensitized to both pollen as revealed by skin prick testing (62 vs. 59%) and IgE immunoblotting (85 vs. 40%). Several clinically relevant allergens were recognized by patients' serum IgE in maize and rice pollen extracts. Conclusion: the high levels of maize and rice pollen sensitization should be related, in this tropical region, to a specific environmental exposure including i) a proximity of the population to the allergenic sources and ii) a putative exacerbating effect of a highly polluted urban atmosphere on pollen allergenicity. Cross reactivities between wild and cultivated grasses and also between rice and maize pollen are involved as well as some specific maize sensitizations. The presence of dense urban and peri-urban agriculture, in various African regions and worldwide, could be a high environmental risk factor for people sensitive to maize pollen

Colloidal stability of tannins: astringency, wine tasting and beyond

Tannin-tannin and tannin-protein interactions in water-ethanol solvent mixtures are studied in the context of red wine tasting. While tannin self-aggregation is relevant for visual aspect of wine tasting (limpidity and related colloidal phenomena), tannin affinities for salivary proline-rich proteins is fundamental for a wide spectrum of organoleptic properties related to astringency. Tannin-tannin interactions are analyzed in water-ethanol wine-like solvents and the precipitation map is constructed for a typical grape tannin. The interaction between tannins and human salivary proline-rich proteins (PRP) are investigated in the framework of the shell model for micellization, known for describing tannin-induced aggregation of beta-casein. Tannin-assisted micellization and compaction of proteins observed by SAXS are described quantitatively and discussed in the case of astringency

Interactions between wine phenolic compounds and human saliva in astringency perception

[EN] Astringency is a complex perceptual phenomenon involving several sensations that are perceived simultaneously. The mechanism leading to these sensations has been thoroughly and controversially discussed in the literature and it is still not well understood since there are many contributing factors. Although we are still far from elucidating the mechanisms whereby astringency develops, the interaction between phenolic compounds and proteins (from saliva, oral mucosa or cells) seems to be most important. This review summarizes the recent trends in the protein–phenol interaction, focusing on the effect of the structure of the phenolic compound on the interaction with salivary proteins and on methodologies based on these interactions to determine astringency

Evolutionary dynamics of emblematic Araucaria species (Araucariaceae) in New Caledonia:Nuclear and chloroplast markers suggest recent diversification, introgression, and a tight link between genetics and geography within species

BACKGROUND: New Caledonia harbours a highly diverse and endemic flora, and 13 (out of the 19 worldwide) species of Araucaria are endemic to this territory. Their phylogenetic relationships remain largely unresolved. Using nuclear microsatellites and chloroplast DNA sequencing, we focused on five closely related Araucaria species to investigate among-species relationships and the distribution of within-species genetic diversity across New Caledonia. RESULTS: The species could be clearly distinguished here, except A. montana and A. laubenfelsii that were not differentiated and, at most, form a genetic cline. Given their apparent morphological and ecological similarity, we suggested that these two species may be considered as a single evolutionary unit. We observed cases of nuclear admixture and incongruence between nuclear and chloroplast data, probably explained by introgression and shared ancestral polymorphism. Ancient hybridization was evidenced between A. biramulata and A. laubenfelsii in Mt Do, and is strongly suspected between A. biramulata and A. rulei in Mt Tonta. In both cases, extensive asymmetrical backcrossing eliminated the influence of one parent in the nuclear DNA composition. Shared ancestral polymorphism was also observed for cpDNA, suggesting that species diverged recently, have large effective sizes and/or that cpDNA experienced slow rates of molecular evolution. Within-species genetic structure was pronounced, probably because of low gene flow and significant inbreeding, and appeared clearly influenced by geography. This may be due to survival in distinct refugia during Quaternary climatic oscillations. CONCLUSIONS: The study species probably diverged recently and/or are characterized by a slow rate of cpDNA sequence evolution, and introgression is strongly suspected. Within-species genetic structure is tightly linked with geography. We underline the conservation implications of our results, and highlight several perspectives. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12862-014-0171-6) contains supplementary material, which is available to authorized users

Contribution a l'etude d'auto anticorps monoclonaux anti globule rouge de Souris : specificite croisee anti trimethylammonium; idiotypie; comparaison avec des anticorps monoclonaux anti phosphoryl choline

SIGLECNRS T 56695 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Actualités des réactions croisées pollen-aliment

International audienceAllergy affects 20 to 30% of the population, and respiratory allergies, which play a preponderant role, are due mainly to pollen grains from anemophilous trees and plants. While fewer individuals suffer from food allergies (1–5%), for several decades clinicians having increasingly reported preferential associations of pollen-food sensitization, resulting in extension of symptomatic profiles from respiratory to oral and gastrointestinal reactions through to anaphylactic shock in the presence of co-factors. Between 40 and 60% of food allergies in adolescents and adults are associated with pollen allergies. Structurally similar allergens are responsible for these cross-reactivities between pollen and food, and only some of the 151 allergenic protein families described contain cross-reactive allergens. Three families are very well characterized: the family of pathogenesis-related PR-10 proteins, the prototypical form of which is Bet v 1, the major birch pollen allergen, and profilins and lipid transfer proteins. The other three are thaumatin-like proteins, isoflavone reductases and β-1,3 glucanases. Finally, 3 other allergen families merit further study: the oleosins, for which allergenic data is available concerning their role in food but very few concerning their role in pollen; the polygalacturonases, which for the moment, while present in food containing pollen and plants, have been described as cross-reactive only in tomato and Japanese cedar pollen; and finally, gibberellin-regulated proteins, recently described in certain types of fruit, and, to date, in only one pollen, namely cypress pollen.L’allergie touche 20 à 30 % de la population et les allergies respiratoires, prépondérantes, sont majoritairement dues aux grains de pollen d’arbres et de plantes anémophiles. L’allergie alimentaire touche moins d’individus (1–5 %) mais les cliniciens rapportent depuis quelques dizaines d’années de plus en plus d’associations préférentielles de sensibilisation entre les pollens et certains aliments étendant ainsi le profil symptomatique du respiratoire au digestif voire réaction anaphylactique en présence de cofacteurs. Quarante à 60 % des allergies alimentaires chez les adolescents et les adultes s’accompagneraient d’allergie au pollen. Certains allergènes sont à l’origine de ces réactions croisées pollen/aliment et sur les 151 familles de protéines décrites comme étant allergéniques seules certaines d’entre elles contiennent des allergènes croisants. Trois familles sont très bien caractérisées : la famille des protéines PR-10 dont le prototype est Bet v 1, l’allergène majeur du pollen de bouleau, les profilines et les lipotransférases. Les trois autres sont les protéines thaumatin-like, les isoflavone réductases et les β-1,3 glucanases. Enfin, 3 autres familles mériteraient d’être plus étudiées ; ce sont les oléosines pour lesquelles des données existent dans les aliments mais très peu dans les grains de pollen, les polygalacturonases qui, pour l’instant, bien que présentes dans les pollen et les aliments d’origine végétale, n’ont été décrites comme allergène croisant que dans la tomate et le pollen du cèdre du Japon. Et aussi les protéines régulées par la gibbérelline décrites récemment comme allergènes dans certains fruits et dans un seul pollen pour l’instant, le pollen de cyprès

FACTEURS PRONOSTIQUES DU MELANOME MALIN DE LA CONJONCTIVE (ETUDE ANATOMO-CLINIQUE DE 56 PATIENTS)

PARIS7-Villemin (751102101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Présentation.

Byé Pascal, Poncet Christian. Présentation.. In: Cahiers d'Economie et sociologie rurales, N°46-47, 1er et 2e trimestres 1998. Histoire des techniques en biologie : contributions au débat. pp. 93-96