PMID(sorted ascending)
studies of the hla class ii alleles involved in human responses to ragweed allergens ambrosia artemisiifolia v (ra5s) and ambrosia trifida v (ra5g)previous studies have associated skin test sensitivity and specific ige response to ambrosia artemisiifolia v (amb a v) with hla-dr2, and to ambrosia trifida v (amb t v) with hla-drw52 haplotypes in atopic individuals. using hla class ii typing by restriction fragment length polymorphism (rflp) analysis with drb, dqb and dqa dna probes to define the hla-d alleles, we have demonstrated the association of the dqw6 in 16 out of 16 (100%) amb a v-responsive individuals, compared to 3 out of 18 (17%) ...19921350871
cloning the cdna encoding the ambtv allergen from giant ragweed (ambrosia trifida) pollen.ragweed (ambrosia) pollens contain a number of proteins that cause allergic disease in ragweed-sensitive people. the cloning of the ambtv cdna is important, since the 4.4-kda ambtv, one of the allergens in giant ragweed (ambrosia trifida) pollen, serves as a simple model system to study the basic structural requirements for immune recognition of foreign protein allergens. we report the cloning of the ambtv cdna by means of the polymerase chain reaction (pcr) using degenerate primers. we generate ...19911711499
anaphylactic reaction after the ingestion of chamomile tea: a study of cross-reactivity with other composite pollens.we report a case of an 8-year-old atopic boy in whom ingestion of a chamomile-tea infusion precipitated a severe anaphylactic reaction. the patient suffers from hay fever and bronchial asthma caused by a variety of pollens (grass, olive, and mugwort). this severe reaction was developed after his first ingestion of chamomile tea. studies revealed the presence of immediate skin test reactivity and a positive passive transfer test to chamomile-tea extract. moreover, both specific antichamomile-tea ...19892674263
compositae dermatitis in childhood.compositae dermatitis occurred in a 9-year-old boy with a strong personal and family history of atopy. positive patch test reactions were 2+ for dandelion (taraxacum officinale), false ragweed (ambrosia acanthicarpa), giant ragweed (ambrosia trifida), short ragweed (ambrosia artemisifolia), sagebrush (artemisia tridentata), wild feverfew (parthenium hysterophorus), yarrow (achillea millifolium), and tansy (tanacetum vulgare) and 1+ for dahlia species and english ivy (hedera helix). patch tests w ...19873827282
the sensitizing capacity of compositae plants. vi. guinea pig sensitization experiments with ornamental plants and weeds using different methods.experimental studies in guinea pigs using ether extracts of 20 different species of the compositae plant family were carried out with the open epicutaneous method (oet) and the guinea pig maximization test (gpmt). the results demonstrate that cnicus benedictus (blessed thistle), chrysanthemum leucanthemum (marguerite, ox-eye daisy) and helianthus debilis (dwarf sunflower) are strong sensitizers while helenium amarum (bitterweed), gaillardia amblyodon (blanket flower), artemisia ludoviciana (prai ...19853970585
t cell epitope mapping of ragweed pollen allergen ambrosia artemisiifolia (amb a 5) and ambrosia trifida (amb t 5) and the role of free sulfhydryl groups in t cell recognition.ambrosia artemisiifolia (amb a 5; ra5s) and ambrosia trifida (amb t 5; ra5g) are homologous allergens purified from short and giant ragweed pollen, respectively. allergic human sera and hyperimmunized animal antisera directed against amb a 5 or amb t 5 show a high degree of species specificity, with little or no cross-reactivity between these two allergens, suggesting that the major ab binding epitopes of amb a 5 and amb t 5 are distinct. overlapping synthetic peptides derived from the allergen ...19957594515
hla-dq6 and hla-dq8 transgenic mice respond to ragweed allergens and recognize a distinct set of epitopes on short and giant ragweed group 5 antigens.we have investigated the genetic and molecular basis of immune responsiveness to short ragweed (srw) (ambrosia artemisiifolia) extract, and group 5 allergens from short and giant (ambrosia trifida) ragweed using transgenic mice expressing dq6 (hla-dqa1*0103, hla-dqb1*0601) and dq8 (hla-dqa1*0301, hla-dqb1*0302) genes in class ii knockout (a beta0) mice. panels of overlapping peptides spanning the amb a 5 and amb t 5 ags were synthesized. mice were immunized with whole srw extract or individual p ...19989712076
structural analysis of n-glycans from allergenic grass, ragweed and tree pollens: core alpha1,3-linked fucose and xylose present in all pollens examined.the n-glycans from soluble extracts of ten pollens were examined. the pyridylaminated oligosaccharides derived from these sources were subject to gel filtration and reverse-phase hplc, in conjunction with exoglycosidase digests, and in some cases matrix-assisted laser desorption-ionisation mass spectrometry. in comparison to known structures, it was possible to determine the major structures of the n-glycans derived from kentucky blue grass (poa pratensis), rye (secale cerale), ryegrass (lolium ...199810386890
intraspecific differences in olfactory sensilla in relation to diet breadth in uroleucon ambrosiae (homoptera: aphididae).the olfactory plate organs found on the proximal segments of aphid antennae, the secondary rhinaria, were studied in apterae of the aphid uroleucon ambrosiae. the numbers and shapes of these structures are important taxonomic characters in aphididae, but they also show intraspecific variation within a morph. in this study, numbers were found to vary with aphid size but, independent of size, were greater in aphids collected in the eastern than in the southwestern united states. in addition, the s ...200010906745
a water potential threshold for the increase of abscisic acid in leaves.a relationship between abscisic acid concentration and leaf water status is reported. water potentials were measured in leaves of ambrosia artemisiifolia l. and ambrosia trifida l. throughout a period of dehydration of intact plants. tissues from the same leaves were analyzed for abscisic acid. for both species, abscisic acid began to increase in a critical water potential range (-10 to -12 atmospheres). these data suggest a threshold water potential that stimulates abscisic acid synthesis. the ...197416658642
[absorption and accumulation of heavy metals by plants around a smelter].the study on the absorption and accumulation of heavy metals lead, zinc, copper and cadmium by 8 plant species around a smelter showed that the metals accumulation by plants differed with plant species, their parts, and kinds of metals. abutilon theophrasti had a higher capability of absorbing and accumulating pb, conyza canadensis, ambrosia trifida, polygonumn lapathifolium, a. theophrasti, solanum nigrum, chenopodium acuminatum and helianthus tuberosus had a higher capability of absorbing and ...200616724753
host plants of the tarnished plant bug (heteroptera: miridae) in central texas.the tarnished plant bug, lygus lineolaris (palisot de beauvois), has taken on added importance as a pest of cotton in the cotton belt after successful eradication efforts for the boll weevil (anthonomus grandis grandis boheman). because the southern blacklands region of central texas is in advanced stages of boll weevil eradication, blooming weeds and selected row crops were sampled during a 3-yr study to determine lygus species composition and associated temporal host plants. l. lineolaris was ...200717716463
chemical composition and antimicrobial activity of the essential oil from ambrosia trifida l.the essential oil obtained by steam distillation of dried aerial parts of ambrosia trifida l. from northeast china was analyzed by gc and gc-ms. the essential oil yield based on dried plant material was 0.12% and thirty-five compounds (corresponding to 86.7% of the total weight) were identified. the main components were: bornyl acetate (15.5%), borneol (8.5%), caryophyllene oxide (8.3%), alpha-pinene (8.0%), germacrene d (6.3%), beta-caryophyllene (4.6%), trans-carveol (2.9%), beta-myrcene (2.6% ...200617971726
weed species shifts in glyphosate-resistant crops.the adoption of glyphosate-based crop production systems has been one of the most important revolutions in the history of agriculture. changes in weed communities owing to species that do not respond to current glyphosate-based management tactics are rapidly increasing. clearly, glyphosate-resistant crops (grcs) do not influence weeds any more than non-transgenic crops. for most crops, the trait itself is essentially benign in the environment. rather, the weed control tactics imposed by growers ...200818232055
evolved glyphosate-resistant weeds around the world: lessons to be learnt.glyphosate is the world's most important herbicide, with many uses that deliver effective and sustained control of a wide spectrum of unwanted (weedy) plant species. until recently there were relatively few reports of weedy plant species evolving resistance to glyphosate. since 1996, the advent and subsequent high adoption of transgenic glyphosate-resistant crops in the americas has meant unprecedented and often exclusive use of glyphosate for weed control over very large areas. consequently, in ...200818273881
ambrosia: a new impending disaster for the israeli allergic population.the pollen of ambrosia (ragweed) is one of the major causes of pollen-induced allergy worldwide. this genus of plants has apparently evolved in north america but later spread into europe and asia. flowering of the ambrosias starts in mid-july and continues throughout the autumn and is a cause of major morbidity to allergic sensitized patients. the invasion of new species of ambrosia into israel is still in progress. plants of ambrosia artemisiifolia (american short ragweed), ambrosia trifida (am ...200819160941
the specific ige reactivity pattern of weed pollen-induced allergic rhinitis patients.specific immunoglobulin e (ige) reactivity towards the major mugwort allergen art v 1 is a good indicator for art v sensitization. allergens from the ragweed species amb t and amb a possibly share common ige-binding epitopes.201121189055
uv and visible light screening by individual sporopollenin exines derived from lycopodium clavatum (club moss) and ambrosia trifida (giant ragweed).we have investigated the uv-visible light transmission of three types of micrometre-sized sporopollenin exine shells, two derived from lycopodium clavatum (club moss) spores and one from ambrosia trifida (giant ragweed) pollen. we have used spectrophotometer measurements of partial monolayers of exines and microscope absorbance imaging to derive the light transmission properties of individual exines. measurements have been made for exines in air when light transmission losses are due to a combin ...201121232973
[effects of light intensity on the phenotypic plasticity of invasive species ambrosia trifida].through artificial shading, this paper studied the phenotypic plasticity of invasive species ambrosia trifida in its morphology, biomass allocation, and photosynthesis characteristics in response to different light intensities. as compared with the control, shading increased the stem height, crown width, leaf area, specific leaf area, and the proportion of leaf biomass in total biomass of a. trifida significantly, but decreased the total biomass, biomass per unit leaf area, and root to shoot rat ...201223173451
[ambrosia pollinosis].pollinosis is now called seasonal allergic rhinitis by the international terminology but pollinosis includes many other symptoms and so we will use the term ambrosia pollinosis in this article. the characteristics of ragweed pollinosis are: severity, duration from august to september and the presence of asthma and/or tracheitis in about 50% of cases. ambrosia: phanerogam, dicotyledon, annual plant, monoic. in france, fields in the mid rhône valley are covered with ambrosia artemisiifolia l. but ...201323664290
an affinity-effect relationship for microbial communities in plant-soil feedback loops involving soil microorganisms can regulate plant populations. here, we hypothesize that microorganisms are most likely to play a role in plant-soil feedback loops when they possess an affinity for a particular plant and the capacity to consistently affect the growth of that plant for good or ill. we characterized microbial communities using whole-community dna fingerprinting from multiple "home-and-away" experiments involving giant ragweed (ambrosia trifida l.) and common sunflowe ...201424402363
[correlation between the magnitude of skin prick test reactivity and pollen-specific serum ige levels in patients with respiratory allergy].for the etiological diagnosis of allergic respiratory diseases skin tests or specific serum ige determination are used.201524912996
the role of biochar, natural iron oxides, and nanomaterials as soil amendments for immobilizing metals in shooting range soil.high concentration of toxic metals in military shooting range soils poses a significant environmental concern due to the potential release of metals, such as pb, cu, and sb, and hence requires remediation. the current study examined the effectiveness of buffalo weed (ambrosia trifida l.) biomass and its derived biochars at pyrolytic temperatures of 300 and 700 °c, natural iron oxides (nre), gibbsite, and silver nanoparticles on metal immobilization together with soil quality after 1-year soil in ...201525794596
short ragweeds is highly cross-reactive with other ragweeds.the most widespread ragweed (ambrosia) species in north america are short ragweed (ambrosia artemisiifolia; amb a), giant ragweed (ambrosia trifida; amb t), and western ragweed (ambrosia psilostachya; amb p). varied geographic distributions of ragweed species raise questions regarding the need for ragweed species-specific allergen immunotherapy.201526507708
contemporary evolution of host plant range expansion in an introduced herbivorous beetle ophraella range expansion of herbivorous insects is a key event in ecological speciation and insect pest management. however, the mechanistic processes are relatively unknown because it is difficult to observe the ongoing host range expansion in natural population. in this study, we focused on the ongoing host range expansion in introduced populations of the ragweed leaf beetle, ophraella communa, to estimate the evolutionary process of host plant range expansion of a herbivorous insect. in the nativ ...201626728888
glyphosate resistance in ambrosia trifida: i. novel rapid cell death response to glyphosate.glyphosate-resistant (gr) ambrosia trifida is now present in the midwestern us and southwestern, ontario, canada. two distinct gr phenotypes are known, including a rapid response (gr rr) phenotype that exhibits cell death within hours after treatment, and a non-rapid response (gr nrr) phenotype. the mechanisms of resistance in both gr rr and gr nrr remain unknown. here we present a description of the rr phenotype and investigation of target-site mechanisms on multiple a. trifida accessions.201728266132
glyphosate resistance in ambrosia trifida: ii. rapid response physiology and non-target site resistance.the glyphosate-resistant rapid response (gr rr) resistance mechanism in ambrosia trifida is not due to target site resistance (tsr) mechanisms. this study explores the physiology of the rapid response and the possibility of reduced translocation and vacuolar sequestration as non-target-site resistance (ntsr) mechanisms.201728276187
photosynthetic symmetry of sun and shade leaves of different orientations.the photosynthetic responses to light of leaves irradiated on the adaxial or abaxial surfaces, were measured for plants with contrasting leaf orientations. for vertical-leaf species of open habitats (eryngium yuccifolium and silphium terebinthinaceum), photosynthetic rates were identical when irradiated on either surface. however, for horizontal-leaf species of open habitats (ambrosia trifida and solidago canadensis), light-saturated rates of photosynthesis for adaxial irradiation were 19 to 37% ...199128313351
population distributions of plant size and light environment of giant ragweed (ambrosia trifida l.) at three densities.plots in a naturally occurring population of giant ragweed (ambrosia trifida l.) near ames, iowa, usa were left unthinned (high density,=693 plants/m(2)) or were thinned in early june 1989 to create low and medium densities of 10 and 50 plants/m(2). size and light environment of individual plants were measured at monthly intervals from june to september. by september, low density plants had 15 times greater biomass/plant and 30 times greater leaf area/plant than high density plants, although bio ...199128313697
comparative protein profiles of the ambrosia plants.ragweed pollen is primarily responsible for the hay fever allergies of sufferers throughout the world. a proteome study of three ragweed plants (ambrosia artemisiifolia, ambrosia trifida, and ambrosia psilostachya) was undertaken to document and compare their protein profiles. proteins extracted from the pollen of the three plants were subjected to one dimensional electrophoresis followed by tandem liquid chromatography-mass spectroscopy. peptide sequence mapping permitted discovery of proteins ...201728315734
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