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PubMed1980

[Potential secondary effects in pollen-desensitization with mixed pollen-depot-extracts in regards to foreign body granuloma (author's transl)].

Desensibilitation as a causal therapy in Pollinosis gets increasing importance in the last decennium. The rate of successful results is reported with 50-80 per cent. In general the rate of secondary effects by this therapy is very low. By use of Aluminium oxide as a material of depot the possibility of producing strange body granuloma must be considered. Own experience in this case is reported.

Adolescent↗
PubMed2006

Economic evaluation of sublingual immunotherapy vs symptomatic treatment in adults with pollen-induced respiratory allergy: the Sublingual Immunotherapy Pollen Allergy Italy (SPAI) study.

BACKGROUND: Few data are available on the pharmacoeconomic aspects of immunotherapy. OBJECTIVE: To evaluate, from the health care system and societal perspectives, the costs and consequences of sublingual immunotherapy (SLIT) added to pharmacotherapy compared with drugs alone for respiratory allergy. METHODS: This study compared costs, clinical outcomes, and cost-effectiveness ratios of 2 strategies in the management of allergic rhinitis and asthma, namely, SLIT associated with pharmacotherapy and pharmacotherapy alone (no SLIT). A decision tree was developed and populated with epidemiologic and resource utilization data concerning approximately 2,200 patients. Direct costs included visits, tests, pharmacotherapy, immunotherapy, and hospitalizations. Indirect costs and out-of-pocket drugs were also included. Outcome was calculated as the number of improved patients and asthma cases avoided at 6 years. Sensitivity analysis was performed by varying costs and epidemiologic data. RESULTS: SLIT improved the symptoms of 399 of 1,000 patients and prevented asthma in 229 of 1,000 patients compared with drugs alone. For SLIT added to pharmacotherapy and pharmacotherapy alone, the direct cost per patient at more than 6 years was Euro2,400 and Euro3,026, whereas the indirect cost was Euro1,913 and Euro3,400. CONCLUSION: From both perspectives and for both effectiveness end points, SLIT is less expensive and more effective than pharmacotherapy alone.

Administration, Sublingual↗
PubMed2004

Allergenic airborne grass pollen in Szczecin, Poland.

Grass pollens are known as very potent aeroallergens. The aim of the study was to analyse the grass pollen season in Szczecin (western Poland) in the years 2000-2003 and to establish a relationship between the meteorological conditions and the pollen counts of Poaceae. The meteorological parameters analysed were the maximum and mean air temperature, relative humidity, amount of precipitation and wind speed. Measurements were performed mainly by the volumetric method. In parallel, gravimetric monitoring was conducted in 4 Szczecin city districts in order to establish the spatial distribution of pollen in aeroplankton. Pollen seasons were defined as the periods in which 95 % of the total catch occurred. In the 4 years studied, the lowest concentration of grass pollen was observed in 2000 with the maximum value of 123 pollen grains in 1 m3 per 24 h. In subsequent seasons, the concentration of Poaceae pollen increased and the highest concentration of grass pollen, equal to 809 pollen grains in 1 m3 per 24 h was noted in 2003. The majority of Poaceae species have constant periods of pollen release and the high number of their species means that the pollen season is long and lasts from the beginning of May until the middle of September. The longest pollen season was observed in the year 2000 when the lowest pollen count was found. In sensitive persons the symptoms of pollinosis occur after some threshold pollen count value, which for grass is 30 grains in 1 m3 per 24 h. Therefore, the greatest threat from Poaceae pollen allergens is noted from the middle of May and until the end of July, and at the beginning of September. Analysis of the pollen distribution in different Szczecin city districts determined by the gravimetric method, has shown that the highest exposure to grass pollen allergens occurs in the districts Zelechowa and Sródmieście, in the area with parks, villas and gardens or garden allotments. However, in the pollen season the threshold Poaceae pollen count value is usually exceeded in the entire city. Statistically significant correlations have been found between the grass pollen count in the air and the maximum wind speed, air temperature, amount of precipitation and relative air humidity. The pollen count of grass is determined by the diversity of local flora and weather conditions, especially by the air temperature and relative humidity.

Allergens↗
PubMedDate not supplied

Viability and seasonal distribution patterns of Scots pine pollen in Finland.

Germination ability and airborne counts of Scots pine (Pinus sylvestris L.) pollen were studied during the spring of 1993 at Turku in southern Finland (60 degrees 32' N, 22 degrees 28' E) and at Utsjoki in northern Finland (69 degrees 45' N, 27 degrees 01' E). Pollen waas trapped from the beginning of May to the end of June in a high-volume air sampler. Germination tests were performed to determine the in vitro pollen viability of the trapped pollen. Airborne pine pollen counts were obtained from a continuously operating Burkard trap located near each high-volume sampler. When male flowering began, phenological observations were carried out on pollen grains collected in rotored samplers located in pine and spruce stands and open fields near Turku and Utsjoki. In southern Finland, the peak period of pine pollen production was short, lasting for only 3 days, but it accounted for about 80% of the total germinating pine pollen yield for the year. The peak count was on May 20, with over 2000 germinating pollen grains per cubic meter of air. Pollen germination rates of up to 70% were obtained during the week preceding the local pollen peak, and rates reached almost 90% on the peak day. Pollen viability remained at 45 to 65% for 1 week after the peak. There was no significant difference between the pollen counts for day and night, indicating that during the main pollen season, the pollen source was close to Turku. Before the local pollen peak, the counts of living pine pollen were low, indicating that pine pollen transported over long distances was of little ecological importance in 1993 in the Turku area. In northern Finland, the first pollen grains were caught on July 4, and the peak day was July 13. However, no viable pollen was observed during this period, indicating that there was little gene drift from southern to northern Finland in 1993.

Journal Article↗
PubMed1997

IgE crossreactivity between mugwort pollen (Artemisia vulgaris) and hazelnut (Abellana nux) in sera from patients with sensitivity to both extracts.

BACKGROUND: An association between sensitization to Compositae pollens and hypersensitivity to hazelnut has been previously described. There is no previous in vitro study about crossreactivity between mugwort pollen and hazelnut. OBJECTIVES: To study mugwort pollen and hazelnut allergens and to assess if there is IgE crossreactivity between mugwort pollen and hazelnut. METHODS: A serum pool formed by 28 individual sera with specific IgE to mugwort pollen and hazelnut was used to investigate IgE crossreactivity. RAST-inhibition, SDS-PAGE/IEF immunoblotting inhibition assays were performed by preincubation of the sera with mugwort pollen and hazelnut. RESULTS: RAST to hazelnut was inhibited up to 63% by mugwort pollen, but the mugwort pollen RAST was only inhibited up to 36% by hazelnut. In SDS-PAGE immunoblotting mugwort pollen showed nine allergens ranging from <16 to 65 kDa and hazelnut had four main allergens: 42 kDa, 17 kDa and <16 kDa (two bands). In the SDS-PAGE immunoblotting inhibition hazelnut partially inhibited all the mugwort pollen bands, except that with 19kDa, whereas mugwort pollen produced a nearly total inhibition of all the hazelnut allergens. In isoelectrofocusing immunoblotting mugwort pollen had two groups of allergens: pI 7.5-8.5 and pI 3.5-5.2 and hazelnut one group of allergens: pI 5.2-5.8. In the isoelectrofocusing immunoblotting inhibition hazelnut produced a partial inhibition of all the bands of mugwort pollen and mugwort pollen partially inhibited all the allergenic bands of hazelnut. CONCLUSIONS: The RAST and SDS-PAGE/IEF immunoblotting inhibition results provide evidence of IgE cross reactivity between mugwort pollen and hazelnut allergens. The inhibition of hazelnut by mugwort pollen is higher than the inhibition of mugwort pollen by hazelnut in both RAST inhibition and SDS-PAGE immunoblotting inhibition. These results suggest that mugwort pollen allergens would behave as primary immunogens in the association between sensitivity to mugwort pollen and hazelnut.

Allergens↗
PubMed2001

The effect of high temperature and high atmospheric CO2 on carbohydrate changes in bell pepper (Capsicum annuum) pollen in relation to its germination.

Pollen viability and germination are known to be sensitive to high temperature (HT). However, the mode by which high temperature impairs pollen functioning is not yet clear. In the present study, we investigated the effect of high temperature on changes occurring in carbohydrate of bell pepper (Capsicum annuum L. cv. Mazurka) pollen in order to find possible relations between these changes and pollen germination under heat stress. When pepper plants were maintained under a moderate HT regime (32/26 degrees C, day/night) for 8 days before flowers have reached anthesis, pollen count at anthesis was similar to that found in plants grown under normal temperatures (NT 28/22 degrees C). However, the in vitro germination, carried out at 25 degrees C, of pollen from HT plants was greatly reduced. This effect matched the marked reduction in the number of seeds per fruit in the HT plants. Maintaining the plants at high air CO2 concentration (800 &mgr;mol mol-1 air) in both temperature treatments did not affect the in vitro germination of pollen from NT plants, but restored germination to near the normal level in pollen from HT plants. Under NT conditions, starch, which was negligible in pollen at meiosis (8 days before anthesis, A-8) started to accumulate at A-4 and continued to accumulate until A-2. From that stage until anthesis, starch was rapidly degraded. On the other hand, sucrose concentration rose from stage A-4 until anthesis. Acid invertase (EC 3.2.1.26) activity rose parallel with the increase of sucrose. In pollen from HT plants, sucrose and starch concentrations were significantly higher at A-1 pollen than in that of NT plants. Under high CO2 conditions, the sucrose concentration in the pollen of HT plants was reduced to levels similar to those in NT pollen. In accordance with the higher sucrose concentration in HT pollen, the acid invertase activity in these pollen grains was lower than in NT pollen. The results suggest that the higher concentrations of sucrose and starch in the pollen grains of HT plants may result from reduction in their metabolism under heat stress. Elevated CO2 concentration, presumably by increasing assimilate availability to the pollen grain, may alleviate the inhibition of sucrose and starch metabolism, thereby increasing their utilization for pollen germination under the HT stress. Acid invertase may have a regulatory role in this system.

Journal Article↗
PubMed2000

IgE immune response to Ginkgo biloba pollen.

BACKGROUND: The ginkgo (Ginkgo biloba L.) continues to be planted as a shade tree in preference to other species in Seoul, Korea. The proportion of ginkgo to total shade trees was 43.2% in 1998, but the allergenic characteristics of ginkgo pollen has not been elucidated. OBJECTIVES: This study was undertaken to obtain information regarding the skin reactivity rate to ginkgo pollen in a population of Korean subjects with respiratory allergy. Possible ginkgo pollen allergens and the cross-reactivity of ginkgo pollen with other prevalent pollens were also examined. METHODS: Four hundred and forty-seven patients with asthma and/or allergic rhinitis were skin prick tested with extract of ginkgo pollen (1:20 wt/vol). Of these patients, positive skin responders (A/H ratio > or =2+) were selected for ELISA and immunoblot experiments. RESULTS: A total of 21 patients (4.7%) showed skin reactivity (A/H ratio > or =2+) to ginkgo pollen in the skin prick test. They were also cosensitized to many other tree, grass, and weed pollens. Sixteen (76%) of the 21 positive skin responders showed specific IgE responses to ginkgo pollen in ELISA. In inhibitory ELISA, IgE binding to ginkgo pollen was inhibited by more than 80% by oak, ryegrass, mugwort, and ragweed; and 34% by hop Japanese; and 10% by rBet v 2 at 10 microg/mL. In immunoblot, 10 out of 21 sera (48%) reacted to the 15-kD protein of ginkgo pollen, 9 (43%) to 33-35 kD, and 8 (38%) to 36-38 kD. In inhibitory immunoblot, IgE binding to ginkgo pollen proteins was almost completely inhibited by oak, ryegrass, mugwort and ragweed, but only partially by hop Japanese and rBet v 2. CONCLUSION: The skin reactivity rate to ginkgo pollen is approximately 4.7% in a population of Korean subjects with respiratory allergy. Since ginkgo pollen has a high cross-reactivity with other prevalent pollens, it could cause clinical symptoms during its pollen season by cross-reacting with the IgE produced in response to other pollens in patients sensitized to multiple pollens.

Adolescent↗
PubMedDate not supplied

Hypersensitivity to common tree pollens in New York City patients.

Testing for tree pollen hypersensitivity typically requires the use of several tree pollens. Identifying patterns of cross-sensitivity to tree pollens could reduce the number of trees used for testing. The goal of this study was to relate reported tree pollen levels to hypersensitivity patterns. Three hundred seventy-one allergy patients were tested serologically for hypersensitivity toward prevalent tree pollens in the surrounding New York area over the years 1993-2000. Specific tree pollens that were examined included oak (Quercus alba), birch (Betula verrucosa), beech (Fagus grandifolia), poplar (Populus deltoides), maple (Acer negundo), ash (Fraxinus americana), hickory (Carya pecan), and elm (Ulmus americana). Statistical analysis of the levels of hypersensitivity was performed to identify correlations and grouping factors. Pollen levels, obtained from published annual pollen and spore reports, were characterized and related to the prevalence of hypersensitivity for the various trees. The highest prevalence of hypersensitivity (score > or = class 1) was for oak (34.3%), birch (32.9%), and maple (32.8%) tree pollens. Lower prevalences were observed for beech (29.6%), hickory (27.1%), ash (26%), elm (24.6%), and poplar (20.6%) trees. Significant correlations were observed between oak, birch, and beech radioallergosorbent test scores. Factor analysis identified two independent pollen groups with oak, birch, and beech consisting of one group and the other five tree pollens constituting the other group. Peak pollen counts clearly were highest for oak, birch, and maple trees. The peak pollen counts corresponded roughly to seropositivity prevalences for the tree pollens. When elm, poplar, and beech test scores were not used to identify patients who were allergic to tree pollens, only 1 of 106 patients with any positive tree radioallergosorbent test score was missed. It is concluded that in the New York City area, hypersensitivity to tree pollens most often is manifested with allergy to oak, birch, and maple tree pollens. Identifying beech, poplar, and elm hypersensitivity adds little toward identifying patients who are allergic to tree pollens. This may relate in part to cross-reactive epitopes. These data suggest that these three trees can be eliminated from testing with only a < 1% loss of sensitivity.

Adolescent↗
PubMed1984

The lectin reactivity and lectin-like activity of allergenic pollen extracts.

The binding of soluble components of pollen grains to plant-stigma receptors can be inhibited by concanavalin A. This lectin-like activity of pollen components is important in the genetic control of plant reproduction. Aqueous extracts of allergenic pollens also react with concanavalin A. Agarose gel-diffusion precipitates were used to survey and characterize the ability of allergenic pollen extracts to react with concanavalin A and other lectins. Concanavalin A alone precipitated with extracts of plantain, American beech, white ash, and corn pollens. Surprisingly, extracts of the pollen from certain plants also precipitated when the extracts were diffused against pollen extracts from other plants. Pollen extracts of alfalfa, white ash, American beech, burweed marsh elder, redtop grass, corn, plantain, orchard grass, and aspen reacted with one or more other pollen extracts. Extract precipitin activity was reliably obtained after extracting pollens for 20 min with pH 7.5, 0.05M Tris buffer in 0.2M of saline. Optimal agarose gel conditions for detecting the precipitin reactions were pH 8.5 to 9.0, 75 mM borate buffer made to an ionic strength of 1.5M with NaCl for concanavalin A pollen reactions and 0.015M with NaCl for pollen-pollen reactions. The presence of the borate ion was necessary for optimal detection of the agarose gel precipitates. Studies of the inhibition of the lectin-pollen and pollen-pollen reactions with specific mono and disaccharides revealed many similarities and differences between the two types of reactions. The high concentrations of glycerol used to stabilize pollen extracts also inhibit these reactions.

Concanavalin A↗
PubMed2006

Zinc is critically required for pollen function and fertilisation in lentil.

The role of zinc (Zn) in reproduction of lentil (Lens culinaris Medik. cv. DPL 15) and the extent to which the Zn requirement for reproduction can be met through supplementation of Zn at the time of initiation of the reproductive phase have been investigated. Low supply (0.1micromol/L) of Zn reduced the size of anthers, the pollen producing capacity and the size and viability of the pollen grains. Scanning electron microscopy (SEM) of pollen grains of Zn deficient plants showed enhanced thickening of exine and wide and raised muri. In vitro germination of pollen grains was reduced by >50% and growth of pollen tubes was retarded. Unlike Zn sufficient plants, the cuticle around the stigmatic papillae of Zn deficient plants remained intact, preventing the interaction between pollen grains and stigmatic exudates that provides the polarity for the growth of pollen tubes through the stylar tract. Zn deficiency increased the activity of acid phosphatase and peroxidase in extracts of pollen grains. Histochemical localisation on the stigmatic surface and native PAGE of the enzyme extracts of pollen grain and stigma exudates showed enhanced expression of acid phosphatase and peroxidase and suppressed expression of esterase in response to Zn deficiency. Zn deficiency reduced the setting of seeds and also their viability. The effect on seed setting was more marked than on in vitro germination of pollen grains, suggesting that the latter was not the exclusive cause of inhibition of fertility. Possibly, loss of fertility was also caused by impairment in pollen-pistil interaction conducive to pollen tube growth and fertilisation. Impairment in pollen structure and function and seed setting was observed even when plants were deprived of Zn at the time of flowering, but to a lesser extent than in plants maintained with low Zn supply from the beginning. Increasing the Zn supply from deficient to sufficient at the initiation of flowering decreased the severity of Zn deficiency effects on pollen and stigma morphology, pollen fertility and seed yield. In conclusion, structural and functional changes induced in pollen grains and stigma of Zn deficient plants and associated decrease in seed setting of lentil indicate a critical requirement of Zn for pollen function and fertilisation that can be partially met by supplementing Zn at the onset of the reproductive phase.

Lens Plant↗
PubMed1991

Monitoring by epifluorescence microscopy of organelle DNA fate during pollen development in five angiosperm species.

The fates of mitochondrial and plastid nucleoids during pollen development in six angiosperm species (Antirrhinum majus, Glycine max, Medicago sativa, Nicotiana tabacum, Pisum sativum, and Trifolium pratense) were examined using epifluorescence microscopy after double staining with 4',6-diamidino-2- phenylindole (DAPI) to stain DNA and with a potentiometric dye (either DiOC7 or rhodamine 123) for visualization of metabolically active mitochondria. From the pollen mother cell stage to the microspore stage of pollen development, mitochondria and plastids both contained DNA detectable by DAPI staining. However, during the further maturation preceding anthesis, mitochondrial DNA became undetectable cytologically in either the generative or the vegetative cell of mature pollen; even in germinated pollen tubes containing hundreds of metabolically active mitochondria undergoing cytoplasmic streaming, vital staining with DAPI failed to reveal mitochondrial DNA. By the mature pollen stage, plastid DNA also became undetectable by DAPI staining in the vegetative cell. However, in the generative cell of mature pollen the timing of plastid DNA disappearance as detected by DAPI varied with the species. Plastid DNA remained detectable only in the generative cells of pollen grains from species known or suspected to have biparental transmission of plastids. The apparent absence of cytologically detectable organelle genomes in living pollen was further examined using molecular methods by hybridizing organelle DNA-specific probes to digests of total DNA from mature pollen and from other organs of A. majus and N. tabacum, both known to be maternal for organelle inheritance. Mitochondrial DNA was detected in pollen of both species; thus the cytological alteration of mitochondrial genomes during pollen development does not correspond with total mtDNA loss from the pollen. Plastid DNA was detectable with molecular probes in N. tabacum pollen but not in A. majus pollen. Since the organelle DNA detected by molecular methods in mature pollen may lie solely in the vegetative cell, further study of the basis of maternal inheritance of mitochondria and plastids will require molecular methods which distinguish vegetative cell from reproductive cell organelle genomes. The biological effect of the striking morphological alteration of organelle genomes during later stages of pollen development, which leaves them detectable by molecular methods but not by DAPI staining, is as yet unknown.

Blotting, Southern↗
PubMed2000

Interpreting atmospheric pollen counts for use in clinical allergy: spatial variability.

BACKGROUND: Atmospheric pollen counts are ubiquitous data, however, few guidelines exist for interpreting them. A fundamental problem involves appreciating spatial variability in atmospheric pollen concentrations, for example, differences in pollen conditions between neighborhoods within a metropolitan area. The significance of this problem is perhaps most manifest in clinical allergy where pollen counts from a single rooftop pollen sampler are often applied to an entire city. OBJECTIVES: This review will consider experimental data concerning spatial variability in atmospheric pollen concentrations. Several guidelines for interpreting pollen counts with respect to this spatial variability will be presented. DATA SOURCES: This review will consider three independent bodies of literature concerning spatial variability in atmospheric pollen concentrations: (1) controlled-release experiments, (2) the paleoecology literature, and (3) atmospheric surveys. RESULTS: Four principal results emerged. First, pollen concentrations in the atmosphere appear to be inherently heterogeneous. Differences in pollen recovery between adjacent points increase in a predictable manner as a function of distance. Second, spatial variability decreases as the distance between pollen sources and destination regions increases. Pollen recovery across a city is most similar when pollen is transported from distant source regions. Third, the size of the source area represented by a pollen sampler depends on the distance between the sampler and the nearest vegetation. Samplers located near vegetation reflect small source areas; source areas expand considerably when the distance to the nearest vegetation increases. Last, individual pollen types travel characteristic distances from their source. Heavy pollen types collected at a particular point reflect a smaller source areas than lighter types which represent much larger source areas. CONCLUSIONS: These conclusions allow allergists to interpret their atmospheric pollen counts with greater sophistication than was previously possible. Mathematical equations presented in this review permit rough calculations concerning source areas.

Air Pollution↗
PubMed2001

Interpreting atmospheric pollen counts for use in clinical allergy: allergic symptomology.

BACKGROUND: Allergists generally consider atmospheric pollen counts to be an estimate of the antigenic challenge confronting allergic individuals. The nature of this challenge depends on the particular pollen types found in the atmosphere and also the airborne concentration of these pollen types. Both clinical experience and clinical investigations support these assumptions; however, a coherent system for relating pollen counts and allergic symptomology does not exist. OBJECTIVE: This review article will systematically review the medical and technical literature concerning the clinical significance of atmospheric pollen counts. DATA SOURCES: This review article will consider three independent bodies of literature: 1) data contrasting human exposure patterns with rooftop pollen counts; 2) data concerning dose-response relationships between atmospheric pollen counts and allergic symptomology; and 3) data concerning methods for indexing atmospheric pollen counts based on a pollen type's in vivo allergenicity and terminal velocity. RESULTS: Three principal results emerged. First, rooftop pollen counts imperfectly approximate human exposure to atmospheric pollen. Differences in both the concentration and type of pollen encountered by humans can be expected to differ from samples obtained on rooftops. Second, allergic symptomology is positively correlated with atmospheric pollen counts. Investigations involving Betula (birch) pollen offer quantitative dose-response models. Complex, nonlinear relationships that seem to reflect both the priming effect and late-phase reactions exist. Last, atmospheric pollen counts can be indexed based on a contemporary application of Thommen's postulates. This system provides allergists with a means to estimate the clinical significance of various pollen types by combining data concerning in vivo allergenicity and terminal velocity. CONCLUSIONS: These conclusions should allow allergists to judge the clinical significance of atmospheric pollen counts with greater sophistication than was previously possible.

Air Pollution↗