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[Seasonal fluctuations of substance P and vasoactive intestinal peptide concentrations in nasal secretions of patients with nasal allergy to Japanese cedar pollen].

Substance P (SP) and vasoactive intestinal peptide (VIP) concentrations in nasal secretions and plasma from patients with nasal allergy to Japanese cedar pollen and healthy volunteers were measured from Jan to Dec, 1991 using EIA established by us. Simultaneously, the numbers of airborne pollens of Japanese cedar and cypress were counted, and the relation to the SP and VIP concentrations in nasal secretions from the patients with nasal allergy to Japanese cedar pollen was studied. The mean SP concentration in nasal secretions from the patients with nasal allergy to Japanese cedar pollen in the pollination season was 81.9 +/- 48.4 fmol/mg protein, which was significantly higher than that in the non-pollination season (30.4 +/- 14.7 fmol/mg protein) (p < 0.01). Likewise, the mean VIP concentration in nasal secretions from the patients with nasal allergy to Japanese cedar pollen in the pollination season was 14.2 +/- 10.4 fmol/ml protein, which was significantly higher than that in the non-pollination season (4.2 +/- 3.0 fmol/mg protein) (p < 0.01). The SP and VIP concentrations in nasal secretions from the healthy volunteers were not affected by the scattering of pollens. The SP and VIP concentrations in plasma from the patients and the healthy volunteers were not affected by the scattering of pollens.

Adult

[Phenologic observations of the Rabka health resort in 1990].

Important factors decisive of the health resort's climatic characteristics are the results of aero-phenologic studies. These results take in account the different pollinating seasons of various plants, grasses and weeds. Quantification and qualification of air pollination using the volume method with a Burkhard analytical device. Basing on results the authors have found increasing pollination string from March. At his time the main pollens come from birch, hazel, alder, weeping willow. The concentration of these pollens decrease in April, completely diminishing in May. Grass pollens increase in mid-May, peaking in June to early August. Pine pollens are found in May and June. A characteristic feature of the phenologic calendar is pollination of grass and pines in the same period (late May and June). The results of this are seen in children treated at the Mother and Child Institute Branch in Rabka, who demonstrate increased signs of pollinosis. The results of this study should modify treatment and change prophylaxis in children treated in Rabka.

Air Pollutants

Pollen-pistil incompatibility in Petunia hybrida: changes in the pistil following compatible and incompatible intraspecific crosses.

The structural events in the stigma and transmitting tissue of Petunia hybrida pistils that accompany compatible and incompatible intraspecific pollinations have been investigated in detail, together with the changes in reserve levels that also take place at this time. Many of these phenomena may be explained in terms of 3 phases of secretion by the cells in the upper regions of the transmitting tissue. The first, independent of pollination, results in the deposition of an intercellular matrix, rich in protein and carbohydrate. The second, triggered by pollination, although independent of the compatibility of the pollen grain, involves synthesis of molecules believed to be specific to the S(incompatibility)-gene system. The third phase of secretion occurs only following a compatible mating, and involves the transfer of stylar reserves to support the growth of the pollen tubes. These observations are discussed in terms of current models of the incompatibility mechanism operating in Petunia.

Crosses, Genetic

Histochemical studies on reserve substances and enzymes in female gametophyte of Zea mays.

Cytochemical changes during the early development of maize caryopsis are reported. Changes in the localization of different reserve substances (e.g. polysaccharides, proteins, nucleic acids and lipids) and enzymes (acid phosphatase, esterase, lipase, phosphorylase, succinate dehydrogenase, cytochrome oxidase and peroxidase) have been studied in unfertilized and fertilized ovules. Before pollination very feeble enzyme activity (acid phosphatase, succinate dehydrogenase, cytochrome oxidase and peroxidase) was observed. Reserve substances were present in low amounts before pollination. Pollination stimulated the accumulation of several substances and enzymes in the tip of the nucellus, micropylar zone. Just prior to, during and after fertilization, the cells in the micropylar zone had strong reaction for several enzymes indicating temporary enhancement of metabolic activity in the micropylar zone. The role of antipodals in the storage of reserve food products and nutrition of embryo and early stages of endosperm development is discussed. The pattern of enzymatic changes within the embryo sac reflected the biochemical changes operative during quiescent and active stages. The nucellus of Zea mays contains many enzymes required for hydrolysis of reserved food substances. A role of acid phosphatase in autolysis of nucellar cells, after fertilization is suggested. Post-fertilization increase in the activity of enzymes and accumulation of reserve materials is interpreted as reflecting a presumed increase in the metabolic rate relative to growth and differentiation.

Acid Phosphatase

Rape pollen allergy.

Rape plants are cultivated in southern and central Sweden. These partly wind pollinated plants have an exceedingly rich blooming period with pollinating times (for rape and turnip rape) from 10 May to 24 June (+/- 1--2 weeks). In a patient material from southern Sweden with bronchial asthma and other allergic manifestations, rape pollen allergy was found to occur quite frequently. In 366 consecutive patients positive intracutaneous skin tests to rape pollen extracts were found in 85 patients (23%). 54 patients with positive i.c. skin tests for rape pollen were provocated: 81% of them had positive provocation tests. Patients with symptoms of hay fever and/or bronchial asthma during the pollinating season in regions where rape and related species are cultivated should be examined for rape pollen allergy with i.c. skin tests or RAST.

Adolescent

Orchard netting impacts on biodiversity leading to cascading effects at the ecosystem level.

Agriculture must ensure food production without further compromising the ecosystem functions upon which it depends. Agricultural practices should therefore avoid harming farmland biodiversity, especially of taxa that supply the key ecosystem services (e.g. pollination, pest control and nutrient uptake) that ultimately support crop production. Orchards are among the largest permanent plantations worldwide and are increasingly characterised by the spread of plastic nets used to protect fruits/nuts from either abiotic (anti-hail, anti-rain, shade nets) or biotic (exclusion nets) hazards. Despite having received little attention to date, these nets may impact natural communities, acting both as physical barriers and as drivers of habitat changes to which biota must respond. Species-level responses to netting depend on the organism's ability to enter the netted environment and successfully exploit available resources. Net-mediated ecological filtering and plastic behavioural responses may alter species interactions, leading to cascading ecological impacts that may create species-poorer 'netted communities' with simplified ecological networks. Such changes may erode biological control potential, other ecosystem functions, and overall system stability. We conducted a systematic review on the effects of protection nets on biota, and reported novel empirical evidence on anti-hail nets' impacts on communities of orchard-dwelling birds, flower-visiting insects, and rodents. In total, we identified 48 studies from the literature, however this literature was strongly biased towards apple orchards, western countries, and pest taxa. Net deployment was highly effective in deterring target pest species, in some cases regardless of their original function, as even weather-protection nets limited pest populations. Side effects on non-target taxa were also often reported, such as decreases in pollinators and natural enemies, and/or increases in secondary pests or microbial diseases. However, most assessments largely disregarded non-pest taxa and the broader ecological consequences of netting. The few studies that addressed the effects of nets at the guild/community level, including our empirical study, confirmed that orchard netting resulted in species-poor assemblages, with possible ecosystem-level consequences. We propose that future assessments should pay more attention to the indirect effects of netting on non-target taxa, and on the supply of crop-supporting ecosystem services mediated by wild species occurring in agroecosystems. Due to the trade-offs between these services and net-mediated crop protection, integrated alternatives should be tested to improve the environmental sustainability of food production and biodiversity conservation in farmed landscapes.

Biodiversity

Genomic signature and evolutionary history of completely cleistogamous lineages in the non-photosynthetic orchid Gastrodia.

Despite a long-standing interest since Darwin's time, the genomic implications of obligate self-fertilization remain elusive. Complete cleistogamy-the obligate production of closed, self-pollinating flowers-represents an extreme reproductive strategy. Here, we present the genomic profiles and evolutionary history of two lineages of the mycoheterotrophic orchid Gastrodia, both of which independently acquired complete cleistogamy, based on detailed sampling and a combination of simple sequence repeat (SSR), multiplexed ISSR genotyping by sequencing (MIG-seq) and RNA-seq data. Our analysis reveals clear species delimitation, with no evidence of introgression between the completely cleistogamous species and their co-occurring allogamous sisters. Intriguingly, all analyses indicate that both the completely cleistogamous Gastrodia species and their allogamous sisters exhibit genetic profiles typical of self-pollinating plants. This pattern suggests that their ancestors, probably bearing allogamous flowers, had already evolved mechanisms to mitigate the deleterious effects of selfing, potentially facilitating the emergence of complete cleistogamy through benefits such as reproductive assurance, enhanced colonization ability and species reinforcement. Meanwhile, further analyses suggest that complete cleistogamy evolved very recently (possibly within the last 1000-2000 years) in these two Gastrodia lineages. Combined with the scant evidence of complete cleistogamy outside Gastrodia, our findings imply a limited and ephemeral role for complete cleistogamy in plant speciation.

Biological Evolution

Supergene control of chiral development in mirror-image flowers.

How genes determine the development of chiral structures is a fascinating question. The reciprocal placement of female and male organs on opposite sides of mirror-image flowers promotes efficient cross-pollination. Here, we identified that in butterfly lilies, female and male organs deflect by a combination of genetically controlled chirality and gravitropism, orienting left and right with respect to an external rather than internal reference axis. We found coordinated organ placement to be controlled by a hemizygous supergene containing two candidate causal loci, MIR156-R and YUCCA-R, that are responsible for opposite female and male organ orientation, respectively. The resulting differential placement of pollen carrying the two supergene alleles on pollinators' bodies leads to their transfer to the stigmas of flowers with opposite handedness and maintenance of the reproductive polymorphism.

Alleles

Evidence for sense RNA-mediated protection to PVYN in tobacco plants transformed with the viral coat protein cistron.

The coat protein (CP) cistron of the tobacco veinal necrosis strain of potato virus Y (PVYN), supplemented with translational start signals, was cloned into an Agrobacterium tumefaciens Ti transformation vector. Transformation of tobacco leaf discs resulted in 99 transgenic lines which were subsequently analysed for the presence and expression, at both the transcriptional and translational level, of the CP-gene. Although CP-specific RNA transcripts were produced in all plants no CP could be detected by several sensitive immunological techniques. Upon mechanical inoculation of progeny lines of self-pollinated original transformants (S1) with PVYN, protection levels of 20 and 95%, respectively, could be observed in two out of ten lines tested. This level of protection increased to 100% in the S2 progeny obtained from self-pollination of virus-protected S1 plants. Transformation of tobacco leaf discs with a PVYN CP construct from which the ATG start codon had been removed by site-directed mutagenesis resulted in 57 transgenic lines that all produced CP-specific transcripts. Mechanical inoculation with PVYN of S1 progeny plants of several of these lines resulted in resistance to a similar level and extent as in the S1 progeny of plants transformed with the intact CP cistron. The results obtained strongly suggest that the resistance observed in the transgenic plants is principally based on the presence of PVYN CP RNA sequences rather than on the accumulation of viral coat protein.

Amino Acid Sequence

Directed excision of a transgene from the plant genome.

The effectiveness of loxP-Cre directed excision of a transgene was examined using phenotypic and molecular analyses. Two methods of combining the elements of this system, re-transformation and cross pollination, were found to produce different degrees of excision in the resulting plants. Two linked traits, beta-glucuronidase (GUS) and a gene encoding sulfonylurea-resistant acetolactate synthase (ALSr), were integrated into the genome of tobacco and Arabidopsis. The ALSr gene, bounded by loxP sites, was used as the selectable marker for transformation. The directed loss of the ALSr gene through Cre-mediated excision was demonstrated by the loss of resistance to sulfonylurea herbicides and by Southern blot analysis. The beta-glucuronidase gene remained active. The excision efficiency varied in F1 progeny of different lox and Cre parents and was correlated with the Cre parent. Many of the lox x Cre F1 progeny were chimeric and some F2 progeny retained resistance to sulfonylureas. Re-transformation of lox/ALS/lox/GUS tobacco plants with cre led to much higher efficiency of excision. Lines of tobacco transformants carrying the GUS gene but producing only sulfonylurea-sensitive progeny were obtained using both approaches for introducing cre. Similarly, Arabidopsis lines with GUS activity but no sulfonylurea resistance were generated using cross pollinations.

Acetolactate Synthase

Changes in the antigenic composition of the short ragweed plant during maturation.

Whole ragweed plants were collected before and during the ragweed pollination season and extracts of various portions of the plants were analyzed for antigen E (AgE) and for their inhibitory potency in the radioallergosorbent test (RAST). Ragweed stems and roots contained very low, if any, AgE. AgE was present in very small amounts in anthers prior to pollination season, increased with anther and pollen grain maturation, peaked with the appearance of significant airborne pollen grains in mid-August, and fell slowly through late September. Leaf AgE content also rose during mid- and late August, but brief rinsing reduced antigen E content by almost 50%. Significant RAST inhibitory activity was found only in anthers and the activity paralleled the content of AgE.

Absorption

Fructophilic lactic acid bacteria as a window into multi-scale convergent evolution.

Fructophilic lactic acid bacteria (FLAB) are a group of lactic acid bacteria with unique growth characteristics, that is, poor growth on glucose. Their growth is enhanced in the presence of fructose or external electron acceptors. These organisms inhabit fructose-rich environments such as flowers, fruits, and pollinating insects, particularly honey bees. Apilactobacillus spp. and Fructobacillus spp. are representatives of FLAB, although they belong to phylogenetically distant clades. These organisms commonly possess markedly small genomes with a low number of coding DNA sequences. Furthermore, their genomes are characterized by a markedly reduced number of genes involved in carbohydrate transport and metabolism. Genome reduction in FLAB reflects convergent adaptation to fructose-rich environments rather than general genome streamlining. The two distinct FLAB genera, Fructobacillus and Apilactobacillus, independently lost more than 100 genes in statistically similar orders. In contrast, genes involved in carbohydrate and amino acid metabolism exhibited reversed orders of loss between the two genera. Furthermore, FLAB genomes lack an intact bifunctional alcohol/aldehyde dehydrogenase gene (adhE), which causes their poor growth on glucose. A comparative genomic study suggested the evolutionary process underlying adhE gene decay during adaptation to the fructose-rich environments, including pollinating insects. In conclusion, FLAB represent a unique example of habitat-driven convergent reductive evolution that can be investigated across multiple biological scales - from individual genes to whole genomes - in the diverse LAB group with a wide range of habitats, and partially share the fructophilic evolution with eukaryotic yeasts found in fructose-rich habitats.

Fructose

Phylotranscriptomics Allows Distinguishing Major Gene Flow Events from Incomplete Lineage Sorting in Rapidly Diversifying Mimetic Orchids (Genus Ophrys).

Ophrys orchids (or bee orchids) provide an outstanding example of a plant adaptive radiation. Over the last 5 million years, this genus has diversified into hundreds of taxa as a result of its unconventional pollination strategy, known as "sexual swindling". However, the rapid and substantial diversification of this genus, combined with its capacity for hybridization and large genome size, poses significant challenges in addressing its systematics. We used phylotranscriptomics as a genome complexity reduction technique to infer the phylogenetic relationships among Ophrys main lineages. More than seven thousand gene trees enabled us to determine the relative contributions of gene flow and incomplete lineage sorting (ILS) in Ophrys evolution. First, we propose a new phylogenetic hypothesis for the genus with an unprecedented resolution that largely confirms the relationships between the main Ophrys lineages, but also provides new insights within each subgenera. By combining phylogenetic network inference with introgression analyzes based on gene tree topologies and branch lengths, we then show that the numerous phylogenetic incongruences among gene tree topologies result from a pervasive background of ILS, over which stand out several well-supported, ancient and potentially adaptive gene flow events between lineages. These major gene flow events provide a new perspective on the evolution of the Ophrys genus and its pollination, questioning previous hypotheses inferred without considering its reticulate evolution, and providing a better understanding of discrepancies observed among previous phylogenetic studies of the genus.

Orchidaceae

A maize embryo-specific gene encodes a proline-rich and hydrophobic protein.

A gene from maize that encodes a hybrid proline-rich protein (HyPRP) formed by two well-defined domains, proline-rich and hydrophobic, respectively, has been characterized at the level of its structure and expression. The proline-rich domain is composed of elements PPYV and PPTPRPS, similar to those found in PRP proteins from soybean. The hydrophobic domain is rich in cysteine and is similar to seed proteins, mainly to a soybean hydrophobic seed protein. In maize, HyPRP is encoded by a single gene, and its mRNA accumulates in immature maize zygotic embryos, with a maximum accumulation between 12 and 18 days after pollination. The HyPRP mRNA can also be detected in ovary prior to pollination. In situ hybridization experiments on embryo sections show an expression of the gene in scutellum and in nonvascular cells from the embryo axis. Functional hypotheses related to HyPRP are discussed.

Amino Acid Sequence

Ragweed hay fever: treatment by local passive administration of IgG antibody.

To determine whether the local administration of IgG antibodies might reduce the symptoms of ragweed hay fever, we tested the effect of this treatment in fourteen patients in a double-blind pilot trial. The patients were randomly divided into two groups, treatment and placebo, and their symptoms and medication usage were determined during the ragweed pollination season. One group used a nasal spray consisting of phosphate-buffered saline (PBS) containing human serum albumin, whereas the other used PBS containing purified IgG from a subject with a high titre of IgG antibody to partially purified ragweed antigen E. Treated and control groups used comparable quantities of nasal spray, and neither noted any ill effects. Comparison of individual symptoms of hay fever, medication usage, and total symptom scores showed no significant differences between the groups except a lessening of eye symptoms (P less than 0.05) in the treated group. The results suggest that nasal administration of IgG antibody up to five times daily does not alter the severity of symptoms in ragweed hay fever. Furthermore, total serum IgE protein and specific IgE levels increased comparably in both groups, suggesting that passive administration of IgG antibody does not suppress the production of IgE antibody during the pollination season.

Administration, Intranasal