The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Christopher A. Mullin - One of the best experts on this subject based on the ideXlab platform.
-
Isolation and Identification of Primary Metabolite Feeding Stimulants for Adult Western Corn Rootworm, Diabrotica virgifera virgifera Leconte, from Host Pollens
Journal of Chemical Ecology, 1999Co-Authors: Benedict Hollister, Christopher A. MullinAbstract:Consumption of Pollens from several host plants was quantified for adult western corn rootworm, Diabrotica virgifera virgifera , with significantly more sweet corn and winter squash Pollen consumed than that of common sunflower and Canada goldenrod. Sequential solvent extraction and chromatographic fractionation of host Pollens, guided by a feeding bioassay of respective fractions, isolated dominant phagostimulatory activity in pools of free amino acids. Amino acid profiles were determined by TLC and HPLC analysis. For sweet corn Pollen, proline was predominant, accounting for 70% of a total 95.3 μmol free amino acid/g Pollen; serine, alanine, γ-aminobutyric acid (GABA), and asparagine occurred in decreasing order of concentration. In squash Pollen, β-alanine predominated (30% of 111 μmol amino acid/g Pollen), followed by asparagine, alanine, proline, and GABA. Histidine (42% of 83.8 μmol amino acid/g Pollen), proline, aspartic acid, asparagine, and alanine were dominant for sunflower Pollen; and for goldenrod, proline (51% of 50.6 μmol amino acid/g Pollen), trans -hydroxyproline, serine, histidine, and alanine predominated. The five dominant amino acids from each Pollen accounted for 80–90% of total amino acid content. Simple mixtures of some dominant amino acids, approximating levels found in sweet corn and squash Pollen, gave phagostimulation similar to that of the crude extracts.
-
Behavioral and electrophysiological dose-response relationships in adult western corn rootworm (Diabrotica virgifera virgifera LeConte) for host Pollen amino acids
Journal of Insect Physiology, 1998Co-Authors: Benedict Hollister, Christopher A. MullinAbstract:A strong correlation is shown between taste cell inputs and phagostimulatory outputs with predominant dietary Pollen amino acids for western corn rootworm, Diabrotica virgifera virgifera. Behavioral and electrophysiological dose-response profiles in adult beetles are presented for five major free amino acids in host Pollens. Differential responses were found with strongest phagostimulation and sensory response elicited by L- alanine and L-serine, followed in order by L-proline and β-alanine. y- Aminobutyric acid gave the weakest and most sporadic response. ED50values for phagostimulation and chemosensory input were 28.3 nmol/disk and 13 mM, respectively, for L-alanine and 17 nmol/disk and 11 mM, respectively, for serine. Threshold values for the responses were approximately 1-2 mM. These behavioral and chemosensory dose-response ranges correspond closely to levels of free amino acids present in host plant Pollens. Use of these response values in development of a Pollen chemosensory code for western corn rootworm feeding is discussed.
Benedict Hollister - One of the best experts on this subject based on the ideXlab platform.
-
Isolation and Identification of Primary Metabolite Feeding Stimulants for Adult Western Corn Rootworm, Diabrotica virgifera virgifera Leconte, from Host Pollens
Journal of Chemical Ecology, 1999Co-Authors: Benedict Hollister, Christopher A. MullinAbstract:Consumption of Pollens from several host plants was quantified for adult western corn rootworm, Diabrotica virgifera virgifera , with significantly more sweet corn and winter squash Pollen consumed than that of common sunflower and Canada goldenrod. Sequential solvent extraction and chromatographic fractionation of host Pollens, guided by a feeding bioassay of respective fractions, isolated dominant phagostimulatory activity in pools of free amino acids. Amino acid profiles were determined by TLC and HPLC analysis. For sweet corn Pollen, proline was predominant, accounting for 70% of a total 95.3 μmol free amino acid/g Pollen; serine, alanine, γ-aminobutyric acid (GABA), and asparagine occurred in decreasing order of concentration. In squash Pollen, β-alanine predominated (30% of 111 μmol amino acid/g Pollen), followed by asparagine, alanine, proline, and GABA. Histidine (42% of 83.8 μmol amino acid/g Pollen), proline, aspartic acid, asparagine, and alanine were dominant for sunflower Pollen; and for goldenrod, proline (51% of 50.6 μmol amino acid/g Pollen), trans -hydroxyproline, serine, histidine, and alanine predominated. The five dominant amino acids from each Pollen accounted for 80–90% of total amino acid content. Simple mixtures of some dominant amino acids, approximating levels found in sweet corn and squash Pollen, gave phagostimulation similar to that of the crude extracts.
-
Behavioral and electrophysiological dose-response relationships in adult western corn rootworm (Diabrotica virgifera virgifera LeConte) for host Pollen amino acids
Journal of Insect Physiology, 1998Co-Authors: Benedict Hollister, Christopher A. MullinAbstract:A strong correlation is shown between taste cell inputs and phagostimulatory outputs with predominant dietary Pollen amino acids for western corn rootworm, Diabrotica virgifera virgifera. Behavioral and electrophysiological dose-response profiles in adult beetles are presented for five major free amino acids in host Pollens. Differential responses were found with strongest phagostimulation and sensory response elicited by L- alanine and L-serine, followed in order by L-proline and β-alanine. y- Aminobutyric acid gave the weakest and most sporadic response. ED50values for phagostimulation and chemosensory input were 28.3 nmol/disk and 13 mM, respectively, for L-alanine and 17 nmol/disk and 11 mM, respectively, for serine. Threshold values for the responses were approximately 1-2 mM. These behavioral and chemosensory dose-response ranges correspond closely to levels of free amino acids present in host plant Pollens. Use of these response values in development of a Pollen chemosensory code for western corn rootworm feeding is discussed.
Janet M. Davies - One of the best experts on this subject based on the ideXlab platform.
-
The molecular allergology of subtropical grass Pollen
Molecular Immunology, 2018Co-Authors: Thina Hareesh Kailaivasan, Janet M. DaviesAbstract:Grass Pollens are amongst the most important aeroallergen sources world-wide triggering allergic rhinoconjunctivitis and asthma in sensitised patients. Much of what we know about the allergen components of grasses is informed by research on Pollen of temperate (Pooideae) species that are abundant in the temperate climate zones. However, climate changes are altering the biogeographical distribution as well as timing and allergenicity of grass Pollens. This provides an impetus for better understanding of the contribution of subtropical subfamilies of grasses to Pollen allergy globally. Pollen of Chloridoideae (e.g. Cynodon dactylon; Bermuda grass) and Panicoideae (e.g. Paspalum notatum; Bahia grass or Sorghum halepense; Johnson grass) subfamilies are clinically important in subtropical zones of Australia, Asia, India, Africa, and America. These grasses differ ecologically and phylogenetically from temperate grasses and, importantly their allergen composition is qualitatively different. For example, subtropical grass Pollens appear to lack the major group 5 grass Pollen allergen family. In this review we summarize current knowledge of the epidemiology and immunology of subtropical Chloridoideae and Pancoideae Pollen allergens, describe the biochemical characteristics of known isoforms and variants as well as properties and structures of subtropical Pollen allergen components. Whilst only one subtropical allergen component; Cyn d 1 of Bermuda grass Pollen, is available commercially for diagnostic use, in a natural purified form, a number of allergens of Panicoideae grass Pollen; Zea m 1, Zea m 3 and Zea m 13 of maize, Pas n 1 and Pas n 13 of Bahia, as well as Sor h 1, Sor h 2, Sor h 13 and Sor h 23 of Johnson grass, have been discovered. Research effort is directed towards making available subtropical grass Pollen allergen components as innovative treatment and diagnostic options that more specifically address the needs of patients from warmer regions of the globe.
-
Grass Pollen allergens globally: the contribution of subtropical grasses to burden of allergic respiratory diseases
Clinical & Experimental Allergy, 2014Co-Authors: Janet M. DaviesAbstract:Grass Pollens of the temperate (Pooideae) subfamily and subtropical subfamilies of grasses are major aeroallergen sources worldwide. The subtropical Chloridoideae (e.g. Cynodon dactylon; Bermuda grass) and Panicoideae (e.g. Paspalum notatum; Bahia grass) species are abundant in parts of Africa, India, Asia, Australia and the Americas, where a large and increasing proportion of the world's population abide. These grasses are phylogenetically and ecologically distinct from temperate grasses. With the advent of global warming, it is conceivable that the geographic distribution of subtropical grasses and the contribution of their Pollen to the burden of allergic rhinitis and asthma will increase. This review aims to provide a comprehensive synthesis of the current global knowledge of (i) regional variation in allergic sensitivity to subtropical grass Pollens, (ii) molecular allergenic components of subtropical grass Pollens and (iii) allergic responses to subtropical grass Pollen allergens in relevant populations. Patients from subtropical regions of the world show higher allergic sensitivity to grass Pollens of Chloridoideae and Panicoideae grasses, than to temperate grass Pollens. The group 1 allergens are amongst the allergen components of subtropical grass Pollens, but the group 5 allergens, by which temperate grass Pollen extracts are standardized for allergen content, appear to be absent from both subfamilies of subtropical grasses. Whilst there are shared allergenic components and antigenic determinants, there are additional clinically relevant subfamily-specific differences, at T- and B-cell levels, between Pollen allergens of subtropical and temperate grasses. Differential immune recognition of subtropical grass Pollens is likely to impact upon the efficacy of allergen immunotherapy of patients who are primarily sensitized to subtropical grass Pollens. The literature reviewed herein highlights the clinical need to standardize allergen preparations for both types of subtropical grass Pollens to achieve optimal diagnosis and treatment of patients with allergic respiratory disease in subtropical regions of the world.
-
Grass Pollen allergens
2014Co-Authors: Jörg Kleine-tebbe, Janet M. DaviesAbstract:Pollens from diverse grass plants are main contributors to seasonal inhalant allergies worldwide. Grass group 1 and 5 allergens represent highly cross-reactive and potent major allergens, group 5 present only in temperate climate grasses (Pooideae). Depending on climate and region, global sensitization rates to grass Pollen vary between 1% to 30% of the general population,. Strong evidence supports specific immunotherapy with grass Pollen extracts.
-
Grass Pollen allergens globally: The contribution of subtropical grasses to burden of allergic respiratory diseases
2014Co-Authors: Janet M. DaviesAbstract:Grass Pollens of the temperate (Pooideae) subfamily and subtropical subfamilies of grasses are major aeroallergen sources worldwide. The subtropical Chloridoideae (e.g. Cynodon dactylon; Bermuda grass) and Panicoideae (e.g. Paspalum notatum; Bahia grass) species are abundant in parts of Africa, India, Asia, Australia and the Americas, where a large and increasing proportion of the world's population abide. These grasses are phylogenetically and ecologically distinct from temperate grasses. With the advent of global warming, it is conceivable that the geographic distribution of subtropical grasses and the contribution of their Pollen to the burden of allergic rhinitis and asthma will increase. This review aims to provide a comprehensive synthesis of the current global knowledge of (i) regional variation in allergic sensitivity to subtropical grass Pollens, (ii) molecular allergenic components of subtropical grass Pollens and (iii) allergic responses to subtropical grass Pollen allergens in relevant populations. Patients from subtropical regions of the world show higher allergic sensitivity to grass Pollens of Chloridoideae and Panicoideae grasses, than to temperate grass Pollens. The group 1 allergens are amongst the allergen components of subtropical grass Pollens, but the group 5 allergens, by which temperate grass Pollen extracts are standardized for allergen content, appear to be absent from both subfamilies of subtropical grasses. Whilst there are shared allergenic components and antigenic determinants, there are additional clinically relevant subfamily-specific differences, at T- and B-cell levels, between Pollen allergens of subtropical and temperate grasses. Differential immune recognition of subtropical grass Pollens is likely to impact upon the efficacy of allergen immunotherapy of patients who are primarily sensitized to subtropical grass Pollens. The literature reviewed herein highlights the clinical need to standardize allergen preparations for both types of subtropical grass Pollens to achieve optimal diagnosis and treatment of patients with allergic respiratory disease in subtropical regions of the world. © 2014 John Wiley & Sons Ltd.
-
subtropical grass Pollen allergens are important for allergic respiratory diseases in subtropical regions
Clinical and Translational Allergy, 2012Co-Authors: Janet M. Davies, Hongzhuo Li, Melissa Green, Michelle Towers, John W UphamAbstract:Grass Pollen allergens are a major cause of allergic respiratory disease but traditionally prescribing practice for grass Pollen allergen-specific immunotherapy has favoured Pollen extracts of temperate grasses. Here we aim to compare allergy to subtropical and temperate grass Pollens in patients with allergic rhinitis from a subtropical region of Australia. Sensitization to Pollen extracts of the subtropical Bahia grass (Paspalum notatum), Johnson grass (Sorghum halepense) and Bermuda grass (Cynodon dactylon) as well as the temperate Ryegrass (Lolium perenne) were measured by skin prick in 233 subjects from Brisbane. Grass Pollen-specific IgE reactivity was tested by ELISA and cross-inhibition ELISA. Patients with grass Pollen allergy from a subtropical region showed higher skin prick diameters with subtropical Bahia grass and Bermuda grass Pollens than with Johnson grass and Ryegrass Pollens. IgE reactivity was higher with Pollen of Bahia grass than Bermuda grass, Johnson grass and Ryegrass. Patients showed asymmetric cross-inhibition of IgE reactivity with subtropical grass Pollens that was not blocked by temperate grass Pollen allergens indicating the presence of species-specific IgE binding sites of subtropical grass Pollen allergens that are not represented in temperate grass Pollens. Subtropical grass Pollens are more important allergen sources than temperate grass Pollens for patients from a subtropical region. Targeting allergen-specific immunotherapy to subtropical grass Pollen allergens in patients with allergic rhinitis in subtropical regions could improve treatment efficacy thereby reducing the burden of allergic rhinitis and asthma.
H Sicard - One of the best experts on this subject based on the ideXlab platform.
-
a double blind placebo controlled trial by the sublingual route of immunotherapy with a standardized grass Pollen extract
Allergy, 1994Co-Authors: A Sabbah, S Hassoun, J Sellin, C Andre, H SicardAbstract:Fifty-eight patients with well-documented history of seasonal rhinoconjunctivitis caused by grass Pollens were allocated randomly on a double-blind basis to receive either sublingual therapy with a solution of purified, standardized allergen preparation (Stallergenes) or a matched placebo for 17 weeks. The assessment of the effect of oral immunotherapy, done with drops of five-grass allergen extract, was on the clinical symptoms and on the medication score of the authorized rescue treatments. The actively treated patients had significantly (P<0.05 to P<0.01) fewer symptoms of rhinitis (sneezing and rhinorrhea) and of conjunctivitis (redness and tears) during the Pollen season than the placebo group. Consumption of nasal solution of sodium cromoglycate and of betamethasone and dexchlorpheniramine was significantly less in the desensitized group (P<0.01). Side-effects were negligible. This study concludes that perlingual immunotherapy with grass Pollen extract in grass-Pollen-sensitive seasonal hay fever and conjunctivitis patients is effective, easy to perform, inexpensive, and safe.
A Sabbah - One of the best experts on this subject based on the ideXlab platform.
-
a double blind placebo controlled trial by the sublingual route of immunotherapy with a standardized grass Pollen extract
Allergy, 1994Co-Authors: A Sabbah, S Hassoun, J Sellin, C Andre, H SicardAbstract:Fifty-eight patients with well-documented history of seasonal rhinoconjunctivitis caused by grass Pollens were allocated randomly on a double-blind basis to receive either sublingual therapy with a solution of purified, standardized allergen preparation (Stallergenes) or a matched placebo for 17 weeks. The assessment of the effect of oral immunotherapy, done with drops of five-grass allergen extract, was on the clinical symptoms and on the medication score of the authorized rescue treatments. The actively treated patients had significantly (P<0.05 to P<0.01) fewer symptoms of rhinitis (sneezing and rhinorrhea) and of conjunctivitis (redness and tears) during the Pollen season than the placebo group. Consumption of nasal solution of sodium cromoglycate and of betamethasone and dexchlorpheniramine was significantly less in the desensitized group (P<0.01). Side-effects were negligible. This study concludes that perlingual immunotherapy with grass Pollen extract in grass-Pollen-sensitive seasonal hay fever and conjunctivitis patients is effective, easy to perform, inexpensive, and safe.