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1.
Sci Total Environ ; 773: 145590, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33940736

RESUMO

Pollen allergies have negative impacts on health. Information about airborne pollen concentration can improve symptom management by guiding choices affecting timing of medicines and pollen exposure. Observations provide accurate pollen concentrations at point locations. However, in the contiguous United States and southern Canada (CUSSC), observations are sparse, and sampling is often seasonal, intermittent or both. Modeling pollen concentration can fill in the gaps with estimates where direct observations are unavailable and also provide much-needed forecasts. The goal of this study is to develop and evaluate statistical models that predict daily pollen concentrations using a machine learning Random Forest algorithm. To evaluate our methods, we made retrospective forecasts of four pollen types (Quercus, Cupressaceae, Ambrosia and Poaceae), each in one of four CUSSC locations. Meteorological and vegetation conditions were input to the models at city and regional scales. A data augmentation technique was investigated and found to improve model skill. Models were also developed to forecast pollen in locations where there are no observations. Forecast skill in these models were found to be greater than in previous models. Nevertheless, the skill is limited by the spatiotemporal resolution of the pollen observations.


Assuntos
Alérgenos , Pólen , Canadá , Cidades , América do Norte , Estudos Retrospectivos
2.
Science ; 372(6538): 171-175, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33833120

RESUMO

Sexual reproduction in angiosperms relies on precise communications between the pollen and pistil. The molecular mechanisms underlying these communications remain elusive. We established that in Arabidopsis, a stigmatic gatekeeper, the ANJEA-FERONIA (ANJ-FER) receptor kinase complex, perceives the RAPID ALKALINIZATION FACTOR peptides RALF23 and RALF33 to induce reactive oxygen species (ROS) production in the stigma papillae, whereas pollination reduces stigmatic ROS, allowing pollen hydration. Upon pollination, the POLLEN COAT PROTEIN B-class peptides (PCP-Bs) compete with RALF23/33 for binding to the ANJ-FER complex, leading to a decline of stigmatic ROS that facilitates pollen hydration. Our results elucidate a molecular gating mechanism in which distinct peptide classes from pollen compete with stigma peptides for interaction with a stigmatic receptor kinase complex, allowing the pollen to hydrate and germinate.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Flores/metabolismo , Peptídeos/metabolismo , Pólen/fisiologia , Polinização , Proteínas Quinases/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Estado de Hidratação do Organismo , Espécies Reativas de Oxigênio/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33798095

RESUMO

Pollen exposure weakens the immunity against certain seasonal respiratory viruses by diminishing the antiviral interferon response. Here we investigate whether the same applies to the pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is sensitive to antiviral interferons, if infection waves coincide with high airborne pollen concentrations. Our original hypothesis was that more airborne pollen would lead to increases in infection rates. To examine this, we performed a cross-sectional and longitudinal data analysis on SARS-CoV-2 infection, airborne pollen, and meteorological factors. Our dataset is the most comprehensive, largest possible worldwide from 130 stations, across 31 countries and five continents. To explicitly investigate the effects of social contact, we additionally considered population density of each study area, as well as lockdown effects, in all possible combinations: without any lockdown, with mixed lockdown-no lockdown regime, and under complete lockdown. We found that airborne pollen, sometimes in synergy with humidity and temperature, explained, on average, 44% of the infection rate variability. Infection rates increased after higher pollen concentrations most frequently during the four previous days. Without lockdown, an increase of pollen abundance by 100 pollen/m3 resulted in a 4% average increase of infection rates. Lockdown halved infection rates under similar pollen concentrations. As there can be no preventive measures against airborne pollen exposure, we suggest wide dissemination of pollen-virus coexposure dire effect information to encourage high-risk individuals to wear particle filter masks during high springtime pollen concentrations.


Assuntos
/epidemiologia , Internacionalidade , Pólen/efeitos adversos , /virologia , Geografia , Humanos , Estudos Longitudinais , /fisiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-33808395

RESUMO

AirRater is a free smartphone app developed in 2015, supporting individuals to protect their health from environmental hazards. It does this by providing (i) location-specific and near real-time air quality, pollen and temperature information and (ii) personal symptom tracking functionality. This research sought to evaluate user perceptions of AirRater's usability and effectiveness. We collected demographic data and completed semi-structured interviews with 42 AirRater users, identified emergent themes, and used two frameworks designed to understand and support behavior change-the Behavior Change Wheel (BCW) and the Protective Action Decision Model (PADM)-to interpret results. Of the 42 participants, almost half indicated that experiencing symptoms acted as a prompt for app use. Information provided by the app supported a majority of the 42 participants to make decisions and implement behaviors to protect their health irrespective of their location or context. The majority of participants also indicated that they shared information provided by the app with family, friends and/or colleagues. The evaluation also identified opportunities to improve the app. Several study limitations were identified, which impacts the generalizability of results beyond the populations studied. Despite these limitations, findings facilitated new insights into motivations for behavior change, and contribute to the existing literature investigating the potential for smartphone apps to support health protection from environmental hazards in a changing climate.


Assuntos
Aplicativos Móveis , Smartphone , Suscetibilidade a Doenças , Humanos , Motivação , Pólen
5.
Environ Pollut ; 279: 116566, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33839524

RESUMO

Honey bees Apis mellifera forage in a wide radius around their colony, bringing back contaminated food resources that can function as terrestrial bioindicators of environmental pesticide exposure. Evaluating pesticide exposure risk to pollinators is an ongoing problem. Here we apply five metrics for pesticide exposure risk (prevalence, diversity, concentration, significant pesticide prevalence, and hazard quotient (HQ)) to a nation-wide field study of honey bees, Apis mellifera in the United States. We examined samples from 1055 apiaries over seven years for 218 different pesticide residues and metabolites, determining that bees were exposed to 120 different pesticide products with a mean of 2.78 per sample. Pesticides in pollen were highly prevalent and variable across states. While pesticide diversity increased over time, most detections occurred at levels predicted to be of low risk to colonies. Varroacides contributed most to concentration, followed by fungicides, while insecticides contributed most to diversity above a toxicity threshold. High risk samples contained one of 12 different insecticides or varroacides. Exposures predicted to be low-risk were nevertheless associated with colony morbidity, and low-level fungicide exposures were tied to queen loss, Nosema infection, and brood diseases.


Assuntos
Inseticidas , Nosema , Resíduos de Praguicidas , Praguicidas , Animais , Abelhas , Inseticidas/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Pólen/química , Estados Unidos
6.
Ying Yong Sheng Tai Xue Bao ; 32(2): 441-452, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33650353

RESUMO

Establishing a precise relationship between modern vegetation and surface pollen is the basis and key to quantitatively reconstruct paleovegetation and paleoclimate based on pollen records. The record of plant community plots has been less considered in the statistical analysis of modern vegetation and surface pollen, which limits the quantitative estimation of its precise relationship. In this study, the quantitative relationships of compositions and quantities between modern surface pollen and plant community were analyzed, based on the Bray-Curtis dissimilarity, through the analysis of 33 surface soil samples and corresponding vegetation plots from forest, meadow steppe, typical steppe and desert steppe on the Northeast China Transect. Results showed that, in a single plot, the relationships between vegetation and pollen in compositions and quantities were different across all families and genera, dominant and common families and genera, and less common and rare families and genera, respectively, due to the differences in pollen dispersal and pollen productivity. There were significant differences among different vegetation types. The compositions of meadow steppe differed greatly, while all families and genera, dominant and common families and genera differed greatly in the quantitative relationship in forest. Less common and rare families and genera differed greatly in the compositions in meadow steppe. The vegetation-pollen relationship of different families and genera was basically the same in terms of composition and quantities. According to the Bray-Curtis dissimilarity, pollen taxa could be divided into three types: over-representative, under-representative and representative types. This dissimilarity index represented both the species composition and quantity relationship between vegetation and pollen both at quadrat scale and at specie level, which could be used as an indicator to quantitatively describe the modern vegetation-pollen relationship.


Assuntos
Ecossistema , Pólen , China , Humanos , Plantas
7.
An Acad Bras Cienc ; 93(2): e20190431, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33656049

RESUMO

Oil Tea (Camellia oleifera) is an important woody edible oil plant in China. Oil Tea suffers from low rate of fruit set during production, which is related to poor pollination and fertilization. Pollen vigor is directly related to pollination and fertilization. Using the interspecific hybrid Y3 (C. grijsii × C. oleifera) as plant material, we studied the effects of sucrose, H3BO3, MgSO4, and IAA on pollen germination using an orthogonal design to determine the best culture medium. Results indicated that pollen germination rates were significantly affected by medium components and ranged from 29.13% to 56.84%. Pollen tube length was the longest in the T5 medium surpassing the control group by 489.36 µm. MgSO4 turned out to be the most important germination medium component having great effect on the pollen germination rate. The optimal culture medium to promote pollen tube growth of Oil Tea Y3 was: 1% agar, 150 g·L-1 sucrose, 0.15 g·L-1 H3BO3, 0.07 g·L-1 MgSO4, and 0.01 g·L-1 IAA. The results of this paper may provide information for foliar application of Mg and IAA, which can improve pollen tube growth of Oil Tea in practice.


Assuntos
Pólen , Polinização , China , Meios de Cultura , Germinação , Chá
8.
Sci Total Environ ; 771: 144883, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33736155

RESUMO

Understanding pollen transport pathways and dispersal mechanism from the land to sea is a prerequisite for marine palynological study. Palynological analysis of 164 surface sediment samples in Liaodong Bay, and 39 analogous surface alluvium samples from its five inflowing rivers, identifies the distribution patterns, pathways and possible sources of pollen and spores. The results show that pollen and spore assemblages in surface sediments are well correlated to regional vegetation distribution, and the variations of pollen assemblage in different parts of Liaodong Bay reflected local vegetation changes along the coast. High pollen concentrations are mainly distributed in the estuaries of inflowing rivers, coastal waters and sea muddy areas. The pollen assemblage characteristics of alluvial samples are similar to those from coastal waters with water depths <8.5 m. Samples from the alluvium and surface sediments of coastal waters were dominated by herbaceous pollen taxa including Artemisia, Amaranthaceae, Poaceae, Cyperaceae and Typha. Herbaceous pollen percentages and concentrations decreased as the water depth increased, indicating that pollen and spores in the coastal waters of Liaodong Bay are mainly carried by the inflowing rivers. However, pollen assemblages for samples with water depth >8.5 m are significantly different from those of the alluvium. In samples taken below a depth of 8.5 m, the arboreal pollen is dominated by airborne Pinus, and there is a high number of the waterborne Selaginella fern spores, both of which are sourced from a wider region. In the Liaodong Bay, both wind and ocean current transportation determines the pollen distribution patterns in deeper waters, while fluvial and longshore current transportation determines the pollen assemblages found in shallow waters. The dispersal characteristics of pollen assemblages between the land and the sea in Liaodong Bay provide a theoretical basis for the interpretation of fossil pollen assemblages and past sea level changes.


Assuntos
Baías , Poluentes Químicos da Água , China , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Pólen/química , Rios , Poluentes Químicos da Água/análise
9.
Artigo em Inglês | MEDLINE | ID: mdl-33668873

RESUMO

The abundances of selected elements in different environmental compartments, namely soil, honey, and bee pollen, was determined in this study. For that purpose, sixteen soil and honey samples, and nine pollen samples were taken in the region of Mitrovica, Kosovo. The concentration of elements was measured by ICP-AES and ICP-MS. Pollution level concentrations of Pb, Zn, As, and Cd were observed in soil. The level of soil pollution was estimated by calculating pollution indices. Pb was also observed at high concentrations in honey, as was Cd and Pb in pollen. Pearson's correlation coefficients revealed mostly weak and moderate correlations of the concentrations of the eight selected elements among the soil, honey, and pollen samples. Several groups of elements with geogenic and anthropogenic origin were identified by hierarchical cluster analysis. The concentrations of selected heavy metals for soil and honey were compared to those in neighboring countries, and those for pollen with samples from Turkey, Serbia, and Jordan.


Assuntos
Mel , Metais Pesados , Poluentes do Solo , Animais , Abelhas , Monitoramento Ambiental , Mel/análise , Jordânia , Kosovo , Metais Pesados/análise , Pólen , Sérvia , Solo , Poluentes do Solo/análise , Turquia
10.
Int J Mol Sci ; 22(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670552

RESUMO

Cytoplasmic male sterility (CMS) plays an important role in the application of heterosis in wheat (Triticum aestivum L.). However, the molecular mechanism underlying CMS remains unknown. This study provides a comprehensive morphological and proteomic analysis of the anthers of a P-type CMS wheat line (P) and its maintainer line, Yanshi 9 hao (Y). Cytological observations indicated that the P-type CMS line shows binucleate microspore abortion. In this line, the tapetum degraded early, leading to anther cuticle defects, which could not provide the nutrition needed for microspore development in a timely manner, thus preventing the development of the microspore to the normal binucleate stage. Proteomic analysis revealed novel proteins involved in P-type CMS. Up to 2576 differentially expressed proteins (DEPs) were quantified in all anthers, and these proteins were significantly enriched in oxidative phosphorylation, glycolysis/gluconeogenesis, citrate cycle (TCA cycle), starch and sucrose metabolism, phenylpropanoid biosynthesis, and pyruvate metabolism pathways. These proteins may comprise a network that regulates male sterility in wheat. Based on the function analysis of DEPs involved in the complex network, we concluded that the P-type CMS line may be due to cellular dysfunction caused by disturbed carbohydrate metabolism, inadequate energy supply, and disturbed protein synthesis. These results provide insights into the molecular mechanism underlying male sterility and serve as a valuable resource for researchers in plant biology, in general, and plant sexual reproduction, in particular.


Assuntos
Infertilidade das Plantas/fisiologia , Proteínas de Plantas/metabolismo , Pólen/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Triticum/metabolismo , Citoplasma/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Infertilidade das Plantas/genética , Proteínas de Plantas/genética , Pólen/genética , Pólen/crescimento & desenvolvimento , Proteoma/genética , Triticum/genética , Triticum/crescimento & desenvolvimento
11.
Environ Pollut ; 278: 116913, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33735791

RESUMO

Pollen allergens, widely present in the atmosphere, are the main cause of seasonal respiratory diseases that affect millions of people worldwide. Although previous studies have reported that nitrogen dioxide (NO2) and ozone (O3) promote pollen allergy, the specific biological processes and underlying mechanisms remain less understood. In this study, Platanus pollen grains were exposed to gaseous pollutants (NO2 and O3). We employed environmental electron microscopy, flow cytometry, western blot assay, enzyme-linked immunoassay, ultraviolet absorption spectrometry, circular dichroism, and protein mass spectrometry to characterise the subpollen particles (SPPs) released from pollen grains. Furthermore, we determined the immunogenicity and pathogenicity induced by Platanus pollen allergen a 3 (Pla a 3). Our results demonstrated that NO2 and O3 could damage the pollen cell membranes in SPPs and increase the amount of Pla a 3 allergen released into the atmosphere. Additionally, NO2 and O3 altered the structure of Pla a3 protein through nitrification and oxidation, which not only enhanced the immunogenicity of allergens but also increased the stability of the protein. In vivo analysis using an animal model indicated that NO2 and O3 greatly aggravated pollen-induced pneumonia. Thus, our study provides guidance for the prevention of pollen allergic diseases.


Assuntos
Ozônio , Rinite Alérgica Sazonal , Alérgenos , Animais , Dióxido de Nitrogênio , Pólen
12.
Ecotoxicol Environ Saf ; 215: 112143, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33740489

RESUMO

Risk assessment of pesticides involves ecotoxicological testing. In case pesticide exposure to bees is likely, toxicity tests are performed with honey bees (Apis mellifera), with a tiered approach, for which validated and internationally accepted test protocols exist. However, concerns have grown regarding the protection of non-Apis bees [bumble bees (Bombus spp.), solitary and stingless bees], given their different life cycles and therefore distinct exposure routes. Larvae of solitary bees of the genus Osmia feed on unprocessed pollen during development, yet no toxicity test protocol is internationally accepted or validated to assess the impact of pesticide exposure during this stage of their life cycle. Therefore, the purpose of this study is to further validate a test protocol with two solitary bee species (O. cornuta and O. bicornis) to assess lethal and sublethal effects of pesticide exposure on larval development. Larvae were exposed to thiacloprid (neonicotinoid insecticide) mixed in a new, artificial pollen provision. Both lethal (developmental and winter mortality) and sublethal endpoints (larval development time, pollen provision consumption, cocoon weight, emergence time and adult longevity) were recorded. Effects of lower, more environmentally realistic doses were only reflected in sublethal endpoints. In both bee species, thiacloprid treatment was associated with increased developmental mortality and larval development time, and decreased pollen provision consumption and cocoon weight. The test protocol proved valid and robust and showed that for higher doses of thiacloprid the acute endpoint (larval mortality) is sufficient. In addition, new insights needed to develop a standardized test protocol were acquired, such as testing of a positive control for the first time and selection of male and female individuals at egg level.


Assuntos
Abelhas/fisiologia , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Tiazinas/toxicidade , Animais , Feminino , Himenópteros , Larva/efeitos dos fármacos , Estágios do Ciclo de Vida , Praguicidas/toxicidade , Pólen , Testes de Toxicidade
13.
Vestn Otorinolaringol ; 86(1): 51-57, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33720652

RESUMO

Recently, there has been an increase in the number of patients with allergic rhinitis (AR) and the number of publications devoted to this problem is increasing. The main etiological factors of AR are pollen of trees, meadow and weeds, as well as mold spores, household allergens and epidermis of animals. Epidemiological studies have found that the prevalence and structure of AR are influenced by regional characteristics, such as the climatic and geographical and social characteristics of the region, and successively therapeutic and preventive algorithms in AR are also different. AIM: To examine the phenotype of the incidence of AR in connection with the characteristics of aeroallergens under the influence of climatic and geographical conditions in northern Vietnam, to make a new contribution to knowledge about AR in Asia and to increase the effect of treatment and prevention in this territory. MATERIALS AND RESEARCH METHODS: The study was conducted in the period from 06.2018 to 09.2018 on the basis of the ENT department of Thainguyen Central Hospital, Vietnam. A total of 556 patients with pathology of ENT organs aged 18 to 70 years were examined, 158 cases of chronic rhinitis were revealed. Among data from 158 patients, 64 patients were diagnosed with AR. We used otorhinolaryngological examination, a standard specific allergological examination and carried out aeropolyneological research in the city of the northern Vietnam, from 06.2018 to 06.2019. RESULT: The aerobiological spectrum is dominated by pollen from the families Moraceae, Urticaceae, Poaceae, Acacia, Artemisia, fern spores and fungal spores from the genus Alternaria. Among patients with chronic rhinitis, 40% were diagnosed with AR, 98.44% of them year-round or perennial AR, with predominant sensitization to house dust mites and molds, much more often to plant pollen. Among 9 (14.06%) patients diagnosed with a polyp of the nasal cavity, 6 (9.37%) patients had increased levels of specific IgE in the blood to a mixture of molds. Sensitization in patients with AR with hypertrophy of the mucous membrane of the nasal cavity is predominant on house dust. CONCLUSION: Predominantly, AR in northern Vietnam was year-round. Especially the connection between the formation of a polyp of the nasal cavity and hypersensitivity to fungal spores has been indicated, which may also indicate the role of social factors in further recommendations for the diagnosis, treatment and prevention of AR in patients living in North Vietnam.


Assuntos
Rinite Alérgica Perene , Rinite Alérgica , Adolescente , Adulto , Idoso , Alérgenos , Animais , Humanos , Pessoa de Meia-Idade , Pólen , Rinite Alérgica/epidemiologia , Rinite Alérgica/etiologia , Vietnã/epidemiologia , Adulto Jovem
14.
Molecules ; 26(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670262

RESUMO

Stingless bee-collected pollen (bee bread) is a mixture of bee pollen, bee salivary enzymes, and regurgitated honey, fermented by indigenous microbes during storage in the cerumen pot. Current literature data for bee bread is overshadowed by bee pollen, particularly of honeybee Apis. In regions such as South America, Australia, and Southeast Asia, information on stingless bee bee bread is mainly sought to promote the meliponiculture industry for socioeconomic development. This review aims to highlight the physicochemical properties and health benefits of bee bread from the stingless bee. In addition, it describes the current progress on identification of beneficial microbes associated with bee bread and its relation to the bee gut. This review provides the basis for promoting research on stingless bee bee bread, its nutrients, and microbes for application in the food and pharmaceutical industries.


Assuntos
Abelhas/química , Mel , Própole/química , Glândulas Salivares/química , Animais , Austrália , Abelhas/metabolismo , Fermentação , Pólen/química , Própole/uso terapêutico , Glândulas Salivares/metabolismo , América do Sul
15.
Planta ; 253(4): 83, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33770279

RESUMO

MAIN CONCLUSION: Bioinformatic analysis identified the function of genes regulating wheat fertility. Barley stripe mosaic virus-induced gene silencing verified that the genes TaMut11 and TaSF3 are involved in pollen development and related to fertility conversion. Environment-sensitive genic male sterility is of vital importance to hybrid vigor in crop production and breeding. Therefore, it is meaningful to study the function of the genes related to pollen development and male sterility, which is still not fully understand currently. In this study, YanZhan 4110S, a new thermo-sensitive genic male sterility wheat line, and its near-isogenic line YanZhan 4110 were analyzed. Through comparative transcriptome basic bioinformatics and weighted gene co-expression network to further identify some hub genes, the genes TaMut11 and TaSF3 associated with pollen development and male sterility induced by high-temperature were identified in YanZhan 4110S. Further verification through barley stripe mosaic virus-induced gene silencing elucidated that the silencing of TaMut11 and TaSF3 caused pollen abortion, finally resulting in the declination of fertility. These findings provided data on the abortive mechanism in environment-sensitive genic male sterility wheat.


Assuntos
Temperatura Alta , Infertilidade das Plantas/genética , Pólen/genética , Triticum/genética , Melhoramento Vegetal
16.
Ecotoxicol Environ Saf ; 214: 112105, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33690003

RESUMO

Eusocial Apis mellifera colonies depend on queen longevity and brood viability to survive, as the queen is the sole reproductive individual and the maturing brood replenishes the shorter-lived worker bees. Production of many crops rely on both pesticides and bee pollination to improve crop quantity and quality, yet sublethal impacts of this pesticide exposure is often poorly understood. We investigated the resiliency of queens and their brood after one month of sublethal exposure to field relevant doses of pesticides that mimic exposure during commercial pollination contracts. We exposed full size colonies to pollen contaminated with field-relevant doses of the fungicides (chlorothalonil and propicanizole), insecticides (chlorypyrifos and fenpropathrin) or both, noting a significant reduction in pollen consumption in colonies exposed to fungicides compared to control. While we found no difference in the total amount of pollen collected per colony, a higher proportion of pollen to non-pollen foragers was detected in all pesticide exposed colonies. After ceasing treatments, we measured brood development, discovering a significant increase in brood loss and/or cannibalism across all pesticide exposed groups. Sublethal pesticide exposure in general was linked to reduced production of replacement workers and a change in protein acquisition (pollen vs. non-pollen foraging). Fungicide exposure also resulted in increased loss of the reproductive queen.


Assuntos
Abelhas/efeitos dos fármacos , Clorpirifos/toxicidade , Fungicidas Industriais/toxicidade , Inseticidas/toxicidade , Nitrilos/toxicidade , Pólen , Piretrinas/toxicidade , Triazóis/toxicidade , Animais , Abelhas/fisiologia , Feminino , Polinização , Reprodução/efeitos dos fármacos
17.
An Acad Bras Cienc ; 93(1): e20200392, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787756

RESUMO

Itapuã State Park is located in the municipality of Viamão, between the 30º 20 'and 30º 27' S and between 50º 50' and 51º 05' W, in the state of Rio Grande do Sul, southern Brazil. The Park is one of the state conservation units, maintaining remnants of the Atlantic forest, rocky fields vegetation, coastal forest, "vassoural," mixed grassland, moist, bathed and juncal plains. Artificial pollen traps were installed inside the park, between forest and human-modified field. The study presents a morphological description of 34 plant families, represented by 47 different pollen grains and monilophyte spores (including exotic taxa), unpublished data for the park's palinoflora. Quantitative data revealed the presence of 77% of non-arboreal pollen grains, 20% of arboreal pollen grains, 2% of monilophyte spores and 1% of other that can be both arboreal and non-arboreal pollen grains. Non-arboreal pollen grains, especially Poaceae, dominated in all the traps, even those located in forest areas. The dominance of the human-modified fields around collectors and winds from the northeast influenced the dispersion of these grains. Exotic pollen grains of the Betulaceae family, of Andean origin, also occurred in the pollen rain, resulting from dispersion by atmospheric currents of long distances.


Assuntos
Florestas , Pólen , Brasil , Humanos , Plantas , Chuva
18.
Int J Mol Sci ; 22(4)2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33669963

RESUMO

Because Japanese cedar pollen (JCP) contains beta-1,3-d-glucan (BG), there is concern that its lingering presence in the atmosphere, especially during its scattering period, may cause false positives in the factor-G-based Limulus amebocyte lysate (LAL) assay used to test for deep mycosis (i.e., G-test). Hence, we examined whether the LAL assay would react positively with substances contained in JCP by using the G-test to measure JCP particles and extracts. BG was purified from the JCP extract on a BG-specific affinity column, and the percentage extractability was measured using three different BG-specific quantitative methods. The G-test detected 0.4 pg BG in a single JCP particle and 10 fg from a single particle in the extract. The percentage extractability of JCP-derived BG was not significantly different among the three quantitative methods. As the JCP particles should technically have been removed during serum separation, they should be less likely to be a direct false-positive factor. However, given that the LAL-assay-positive substances in the JCP extract were not distinguishable by the three BG-specific quantitative methods, we conclude that they may cause the background to rise. Therefore, in Japan false positives arising from JCP contamination should be considered when testing patients for deep mycosis.


Assuntos
Cryptomeria/imunologia , Micoses/diagnóstico , Pólen/imunologia , Reações Falso-Positivas , Concentração de Íons de Hidrogênio , Lectinas Tipo C/metabolismo , beta-Glucanas/metabolismo
19.
Yi Chuan ; 43(3): 271-279, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33724211

RESUMO

LRXs (leucine-rich repeat extensins) are chimeric cell wall proteins containing an N-terminal leucine-rich repeat (LRR) and a C-terminal extensin domain. Increasing evidences suggest that LRXs family genes play important roles in pollen germination and pollen tube growth in Arabidopsis thaliana. However, the functions of rice (Oryza sativa L.) LRX genes in pollen development remain poorly understood. Bioinformatics analysis showed that the rice LRX gene family consist of eight members, namely OsPEX3, OsLRX3 and OsLRX5 located on chromosome 1, OsLRX1, OsLRX3, OsLRX2,OsPEX1 and OsPEX2 located on chromosome 2, 5, 6, 11 and 12, respectively. The OsPEX1 gene is preferentially expressed in rice anther, suggesting that it may be involved in the regulation of pollen development. Next, we further investigated the role of the OsPEX1 gene in rice by knockdown of its expression using an RNAi approach. The OsPEX1 RNAi transgenic lines showed a significant decrease in seed setting rate (10%~30%) due to pollen sterility. Further quantitative RT-PCR analysis indicated that the OsPEX1 gene was significantly down-regulated in the RNAi transgenic lines. The results indicate that the OsPEX1plays an important role in the regulation of rice pollen development. Further studies on this gene could provide insights on the molecular and genetic mechanisms in this developmental process.


Assuntos
Oryza , Parede Celular/metabolismo , Fertilidade , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/genética
20.
Georgian Med News ; (310): 101-107, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33658417

RESUMO

Cypress pollen allergy is a widely distributed, highly prevalent and severe winter pollinosis that may be caused by several Cupresaceae species around the Mediterranean basin, in North America and Asia. Exposure to cypress pollen has increased steadily over the last few decades and the prevalence of allergy to cypress pollen has also dramatically increased from 0.6% to 9.8% in the general population and from 9% to 35% in allergic patients, probably because of the allergen load has become more intense. The objective of the study was to evaluate cypress pollen allergy in Georgia and describe clinical characteristics and the molecular profile of sensitization. Patients attended to allergy clinic with suspected cypress pollen allergy (n=492) were included in the study. Diagnostic workup was performed according to local guidelines, specific IgE antibody against cypress allergen was performed using ImmunoCAP and ISAC assay platform. The airborne pollen monitoring was performed with a Burkard Seven Day Volumetric Spore-trap (Burkard Manufacturing Co Ltd, UK) during the seasons of 2019-2020, following the recommendations of European Aerobiology Society. 37.2% of studied cases were positive to cypress diagnostic test. From cypress positive 183 patients only 17 patients (9.2%) had no symptoms during the cypress season. The most frequent symptoms were sneezing and ocular itching (82.9% of patients for both symptoms), rhinorrhea was reported in 77.7% of cases and dry cough and shortness of breath - only in 22.3% (each symptoms). More than half of frequent symptoms were reported as severe. The cypress positive patients were mostly co-sensitized to plant allergen components: grasses (nCyn d1- 61.5% of ISAC positive cases, rPhl p 1 -72.5%, rPhl p 5 - 46.8%), trees (rBet v 1 - 27.5%, nCry j 1 - 78.9%, nPla a 2 - 32.1%) and weeds (nAmb a 1 - 48.6%, nArt v 1 - 20.2%). Our data show that in Georgia, the prevalence of sensitization to cypress pollen in patients attending the allergy clinic is high (every third patient). The clinical symptoms predominantly associated with allergic rhinitis and atopic conjunctivitis, in most cases which are expressing by acute sneezing and ocular itching during the pollen season and all patients are poly-sensitized. This was the first study to give a detailed description of the clinical characteristics of cypress pollen allergic patients in Georgia.


Assuntos
Cupressus , Rinite Alérgica Sazonal , Alérgenos , República da Geórgia , Humanos , Pólen , Rinite Alérgica Sazonal/diagnóstico , Rinite Alérgica Sazonal/epidemiologia
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