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Identification of phenolanine in rape bee pollen and its protective effect and mechanism on alcoholic liver injury
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作者 Cheng Lü Mingjuan Xu +5 位作者 Xinbiao Yang Yanlun Feng Yun Zhu Qun Lu Chengming Wang Rui Liu 《Food Science and Human Wellness》 2025年第2期484-496,共13页
Rape bee pollen has attracted increasing interests for its excellent protective effect against chemicalinduced liver injury owing to its abundant polyphenols.This study aims to analyze the types and contents of phenol... Rape bee pollen has attracted increasing interests for its excellent protective effect against chemicalinduced liver injury owing to its abundant polyphenols.This study aims to analyze the types and contents of phenolamides(seldom concerned)in rape bee pollen and their protective mechanism on alcoholic liver disease(ALD).Different from the previous finding that flavonoids are dominant polyphenols in bee pollen polyphenolic extract,our results demonstrated that there are only three flavonoids but 24 phenolamides in the as-prepared rape bee pollen phenolic extract(PPE).In addition,PPE was found to significantly improve the viability(from 54.9%to 84.1%,89.2%,and 94.0%)of alcohol-induced AML12 cells and alleviate alcoholinduced cell apoptosis(from 28.5%to 22.89%,22.0%,and 17.4%).To dissect the underlying mechanism for the protective effect of PPE against ALD,the molecular pathway was identified by RNA-Seq analysis.Transcriptome data revealed that PPE may protect against ALD by decreasing inflammation,cholesterol,and fatty acid synthesis(P<0.05).The National Institute on Alcohol Abuse and Alcoholism(NIAAA)model was used to further evaluate the hepatoprotective effect of PPE in vivo,and the results validated that PPE could alleviate liver injury and hepatic steatosis(from 22.7%to 11.5%and 10.9%)induced by alcohol.As the dominant polyphenols in PPE,phenolamides can be a class of valuable polyphenolic compounds in bee pollen with the potential to alleviate ALD. 展开更多
关键词 Rape bee pollen Phenolamide Alcoholic liver disease(ALD) AML12s National Institute on Alcohol Abuse and Alcoholism(NIAAA) TRANSCRIPTOME
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Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens 被引量:1
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作者 Yuan Yuan Shun Zhong +3 位作者 Zeyuan Deng Guangyan Li Jinwu Zhang Hongyan Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1567-1577,共11页
The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were i... The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods. 展开更多
关键词 Bee pollen NUTRIENTS Wall disruption Phenolic compounds In vitro digestion
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Effect of different drying methods on the amino acids,α-dicarbonyls and volatile compounds of rape bee pollen 被引量:1
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作者 Yanxiang Bi Jiabao Ni +6 位作者 Xiaofeng Xue Zidan Zhou Wenli Tian Valérie Orsat Sha Yan Wenjun Peng Xiaoming Fang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期517-527,共11页
The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed ... The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were determined.The results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest loss.Glucosone was the dominantα-DCs in RBP and the highest loss was observed after PVD.Aldehydes were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying methods.Comprehensively,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process. 展开更多
关键词 DRYING Bee pollen Free amino acids α-Dicarbonyl compounds Volatile compounds
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Allergen degradation of bee pollen by lactic acid bacteria fermentation and its alleviatory effects on allergic reactions in BALB/c mice
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作者 Shuting Yin Qiangqiang Li +5 位作者 Yuxiao Tao Enning Zhou Kun Wang Wanwen Chen Xiangxin Li Liming Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期349-359,共11页
Food allergy as a global health problem threatens food industry.Bee pollen(BP)is a typical food with allergenic potentials,although it performs various nutritional/pharmacological functions to humans.In this study,lac... Food allergy as a global health problem threatens food industry.Bee pollen(BP)is a typical food with allergenic potentials,although it performs various nutritional/pharmacological functions to humans.In this study,lactic acid bacteria(LAB)were used to ferment Brassica napus BP for alleviating its allergenicity.Four novel allergens(glutaredoxin,oleosin-B2,catalase and lipase)were identified with significant decreases in LAB-fermented BP(FBP)than natural BP by proteomics.Meanwhile,metabolomics analysis showed significant increases of 28 characteristic oligopeptides and amino acids in FBP versus BP,indicating the degradation of LAB on allergens.Moreover,FBP showed alleviatory effects in BALB/c mice,which relieved pathological symptoms and lowered production of allergic mediators.Microbial high-throughput sequencing analysis showed that FBP could regulate gut microbiota and metabolism to strengthen immunity,which were closely correlated with the alleviation of allergic reactivity.These findings could contribute to the development and utilization of hypoallergenic BP products. 展开更多
关键词 Alleviatory effects Lactic acid bacteria fermentation Bee pollen allergen Gut microbiota Host metabolism
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Plant Pollen Grains:A Move Towards Green Drug and Vaccine Delivery Systems 被引量:1
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作者 Siavash Iravani Rajender S.Varma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第8期218-230,共13页
Pollen grains and plant spores have emerged as innovative biomaterials for various applications such as drug/vaccine delivery,catalyst support,and the removal of heavy metals.The natural microcapsules comprising spore... Pollen grains and plant spores have emerged as innovative biomaterials for various applications such as drug/vaccine delivery,catalyst support,and the removal of heavy metals.The natural microcapsules comprising spore shells and pollen grain are designed for protecting the genetic materials of plants from exterior impairments.Two layers make up the shell,the outer layer(exine)that comprised largely of sporopollenin,and the inner layer(intine)that built chiefly of cellulose.These microcapsule shells,namely hollow sporopollenin exine capsules have some salient features such as homogeneity in size,non-toxic nature,resilience to both alkalis and acids,and the potential to withstand at elevated temperatures;they have displayed promising potential for the microencapsulation and the controlled drug delivery/release.The important attribute of mucoadhesion to intestinal tissues can prolong the interaction of sporopollenin with the intestinal mucosa directing to an augmented effectiveness of nutraceutical or drug delivery.Here,current trends and prospects related to the application of plant pollen grains for the delivery of vaccines and drugs and vaccine are discussed. 展开更多
关键词 pollenS SPOROpollenIN Drug delivery Vaccine delivery Plant pollen grains Microcapsule shells
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Vitality and storage condition of Syringa pollen 被引量:6
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作者 周莉 罗凤霞 +1 位作者 代力民 张惠华 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期67-70,共4页
The fresh pollen vitality, the effect of different storage conditions on the pollen vitality, and the difference of vitality among the species of seven species of Syringa were determined in Shenyang, China. The result... The fresh pollen vitality, the effect of different storage conditions on the pollen vitality, and the difference of vitality among the species of seven species of Syringa were determined in Shenyang, China. The results indicated that the pollen vi-tality (81.5%) of Syringa villosa was the highest among the seven tested species, followed by S. microphylla and S. meyeri, and that of S. oblata var. affinis was the lowest. The low temperature was the best condition for storage of pollen of Syringa, and the most proper temperature for the storage was 0-2 癈. The storability of S. microphylla was the best of all, and it could be stored over 60 days at the temperature of 0-2 癈, next was S. villosa and S. meyeri. 展开更多
关键词 SYRINGA pollen VITALITY Storage condition
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Effects of Ion Implantation on in Vitro Pollen Germination and Cellular Organization of Pollen Tube in Pinus thunbergii Parl. (Japanese Black Pine) 被引量:3
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作者 李国平 黄群策 +3 位作者 杨鹭生 代西梅 秦广雍 霍裕平 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第5期618-623,共6页
Low-energy ion implantation, as a new technology to produce mutation in plant breeding, has been widely applied in agriculture in China. But so far there is a little understanding of the underlying mechanisms responsi... Low-energy ion implantation, as a new technology to produce mutation in plant breeding, has been widely applied in agriculture in China. But so far there is a little understanding of the underlying mechanisms responsible for its biological effects at the cellular level. Here we report the biological effects of a nitrogen ion beams of 30 keV on the pollen grains of Pinus thunbergii Parl. In general, ion implantation inhibited pollen germination. The dose-response curve presented a particular saddle-like pattern. Ion implantation also changed the dimension of the elongated tubes and significantly induced tip swelling. Confocal microscopy indicated that the pollen tube tips in P. thunbergii contained an enriched network of microtubules. Ion implantation led to the disruption of microtubules especially in swollen tips. Treatment with colchicine demonstrated that tip swelling was caused by the disruption of microtubules in the tip, indicating a unique role for microtubules in maintaining the tip integrality of the pollen tube in conifer. Our results suggest that ion implantation induce the disruption of microtubule organization in pollen and pollen tubes and subsequently cause morphological abnormalities in the pollen tubes. This study may provide a clue for further investigation on the interaction between low-energy ion beams and pollen tube growth. 展开更多
关键词 ion implantation ion beam pollen tube CYTOSKELETON MICROTUBULES pinus thunbergii parl
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Daily variations of airborne pollen in Beijing Olympic Park during August of three consecutive years and their relationships with meteorological factors 被引量:3
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作者 XU Jing-xian ZHANG De-shan 《Forestry Studies in China》 CAS 2011年第2期154-162,共9页
A three-year aeropalynological study was carried out in the month of August for each of the three years 2005, 2006 and 2007 in the Beijing Olympic Park. A total of 19550 pollen grains were counted (15057 grains in 20... A three-year aeropalynological study was carried out in the month of August for each of the three years 2005, 2006 and 2007 in the Beijing Olympic Park. A total of 19550 pollen grains were counted (15057 grains in 2005, 2717 in 2006 and 1776 in 2007) for the following taxa: Gramineae, Chenopodiaceae, Humulus L., Artemisia L., Ambrosia L. and Pinus L. The analysis indicated that in the three consecutive years of 2005-007, airborne pollen types and daily number of pollen in August in the Beijing Olympic Park were closely related to environmental change and vegetation composition. The daily variations of airborne pollen displayed similar patterns in August in each of the three years, which were affected positively by periods of daily sunshine, negatively by daily relative humidity and daily precipitation. Continuously high daily temperatures and stable daily wind speeds seemed to have little effect on the fluctuation of airborne pollen. 展开更多
关键词 daily variations aeropalynology airborne pollen Beijing Olympic Park
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Effect of fermented bee pollen on metabolic syndrome in high-fat diet-induced mice 被引量:5
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作者 Sha Yan Kai Wang +4 位作者 Xiaoying Wang Aiqun Ou Feiran Wang Liming Wu Xiaofeng Xue 《Food Science and Human Wellness》 SCIE 2021年第3期345-355,共11页
Bee pollen has potential in preventing metabolic syndrome(MetS).The present study aimed to investigate the effect of yeast-fermented wall-broken bee pollen(YB)intervention on ICR mice with MetS induced with a high-fat... Bee pollen has potential in preventing metabolic syndrome(MetS).The present study aimed to investigate the effect of yeast-fermented wall-broken bee pollen(YB)intervention on ICR mice with MetS induced with a high-fat(HF)diet.After YB intervention in mice for 16 weeks,the effect on alleviating MetS was evaluated based on MetS serum parameters,hepatic oxidant status markers and gut microbial populations.The results of animal experiment showed that YB intervention attenuated MetS.Based on multivariate statistical analysis results,YB treatment signifi cantly increased glutathione S-transferase(GST)and catalase(CAT)activities and decreased the malondialdehyde(MDA)level in the liver.Further investigation showed that YB restored the Nrf-2-Keap-1 pathway to alleviate oxidative stress.Additionally,gut microbial community analysis revealed that YB restored the increase in the Firmicutes to Bacteroidetes(F/B)ratio(6.94 for the HF group and 3.74 for HF+YB group)and improved Lactobacillus and Lactococcus abundance induced by the HF diet.Overall,YB improved function and prevented MetS by modulating the gut microbiota and alleviating oxidative stress. 展开更多
关键词 Bee pollen FERMENTATION Gut microbial community Metabolic syndrome
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SURVEY OF AIRBORNE POLLEN IN HUBEI PROVINCE OF CHINA 被引量:3
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作者 Guang-hui Liu Rong-fei Zhu Wei Zhang Wen-jing Li Zhong-xi Wang Huan Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2008年第4期212-217,共6页
Objective To study the genera and seasonal distribution of airborne pollen in Hubei province of China, and its relationship with pollinosis. Methods From November 2003 to October 2004, an airborne pollen investigation... Objective To study the genera and seasonal distribution of airborne pollen in Hubei province of China, and its relationship with pollinosis. Methods From November 2003 to October 2004, an airborne pollen investigation was performed in 16 chosen areas in 12 cities of Hubei province using gravity sedimentation technique. Meanwhile, univalent skin prick tests of pollens were performed and the invasion season was studied on 2 300 patients with pollinosis. Among them, 352 cases underwent the airway responsiveness measurements, and the correlation between airway responsiveness and results of pollen count was analyzed. Results A total of 61 pollen genera were observed and 257 520 pollens were collected. The peak of airborne pollen distribution occurred in two seasons each year: spring (March and April) and autumn (from August to October). The attack of pollinosis corresponded to the peak of pollen distribution. There was a significantly negative relationship between the provocation dose causing a 20% decrease of forced expiratory volume in one second (FEV1) from baseline and airborne pollen concentration (r = -0.6829, P < 0.05). Conclusion This study provides useful information for airborne pollen epidemiology of Hubei province, and it provides important insights to clinical prevention, diagnosis, and treatment of pollen-related allergic diseases. 展开更多
关键词 airborne pollen POLLINOSIS airway responsiveness
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The Effects of Low-Energy Nitrogen Ion Implantation on Pollen Exine Substructure and Pollen Germination of Cedrus deodara 被引量:2
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作者 李国平 黄群策 +1 位作者 秦广雍 霍裕平 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第6期3176-3180,共5页
The aim of this study is to investigate the biological effects of ion beams on pollen. Pollen grains of Cedrus deodara were implanted with 30 keV nitrogen ion beams at doses ranging from 1 × 10^15 ions/cm^2 to 15... The aim of this study is to investigate the biological effects of ion beams on pollen. Pollen grains of Cedrus deodara were implanted with 30 keV nitrogen ion beams at doses ranging from 1 × 10^15 ions/cm^2 to 15 × 10^15 ions/cm^2. The effects of N^+ implantation on the pollen exine substructure were examined using an atomic force microscope (AFM), and the structure and morphology of pollen and pollen tubes were observed using a laser scanning confocal microscope (LSCM). AFM observations distinctly revealed the erosion of the pollen exine caused by N^+ implantation in the micrometer to nanometer range. Typical results showed that the erosion degree was linearly proportional to the ion dose. Pollen germination experiments in vitro indicated that N^+ implantation within a certain dose range increased the rate of pollen germination. The main abnormal phenomena in pollen tubes were also analyzed. Our results suggest that low energy ion implantation with suitable energy and dosage can be used to break the pollen wall to induce a transfer of exogenous DNA into the pollen without any damage to the cytoplasm and nuclei of the pollen. The present study suggests that a combination of the method of ion-beam-induced gene transfer and the pollen-tube pathway method (PTPW) would be a new plant transformation method. 展开更多
关键词 nitrogen ion implantation pollen exine substructure atomic force microscope(AFM) Cedrus deodara (Roxb.) Loud
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Characterization and functional analysis of pollen-specific PwSWEET1 in Picea wilsonii 被引量:2
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作者 Yanni Zhou Xiaoyue Cui +2 位作者 Anni Hu Yahui Miao Lingyun Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1913-1922,共10页
SWEET transporters play a pivotal role in sugar transport in plants.However,their functions in pollen tube growth,especially in coniferous species remain unknown.Here,we used RT-qPCR to reveal that a SWEET1 gene was s... SWEET transporters play a pivotal role in sugar transport in plants.However,their functions in pollen tube growth,especially in coniferous species remain unknown.Here,we used RT-qPCR to reveal that a SWEET1 gene was specifically expressed in pollen and pollen tubes of Picea wilsonii.A pollen germination assay showed that PwSWEET1 was induced by H3BO3 but not by Ca^2+.In a sugar specificity experiment,sucrose(Suc)and glucose(Glc)were effective sugars for pollen germination and pollen tube growth.PwSWEET1 expression was induced most by Suc and Glc.Heterologous expression of PwSWEET1 in yeast showed that PwSWEET1 can restore the glucose absorption in yeast strain EBY.VW4000,which has a hexose absorption defect,and the absorption of glucose is pH-independent.This evidence supports the involvment of PwSWEET1 in boron-dependent glucose transport in pollen germination and pollen tube growth of Picea wilsonii. 展开更多
关键词 PwSWEET1 Picea wilsonii pollen tube Glucose transporter
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Effect of Implantation Machine Parameters on N^+ ion Implantation for Upland Cotton(Gossypium hirsutum L.)Pollen 被引量:1
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作者 岳洁瑜 余立祥 +1 位作者 吴跃进 唐灿明 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第5期640-644,共5页
Effect of parameters of ion implantation machine, including ion energy, total dose, dose rate, impulse energy and implantation interval on the pollen grains of upland cotton implanted with nitrogen ion beam were studi... Effect of parameters of ion implantation machine, including ion energy, total dose, dose rate, impulse energy and implantation interval on the pollen grains of upland cotton implanted with nitrogen ion beam were studied. The best parameters were screened out. The results also showed that the vacuum condition before the nitrogen ion implantation does not affect the pollen viability. 展开更多
关键词 nitrogen ion energy total upland cotton dose dose rate impulse energy INTERVAL pollen
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Ion Implantation Hampers Pollen Tube Growth and Disrupts Actin Cytoskeleton Organization in Pollen Tubes of Pinus thunbergii 被引量:1
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作者 李国平 黄群策 +1 位作者 杨鹭生 秦广雍 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期391-393,共3页
Pollen grains of Pinus thunbergii Parl. (Japanese black pine) were implanted with 30 keV nitrogen ion beams and the effects of nitrogen ion implantation on pollen tube growth in vitro and the organization of actin c... Pollen grains of Pinus thunbergii Parl. (Japanese black pine) were implanted with 30 keV nitrogen ion beams and the effects of nitrogen ion implantation on pollen tube growth in vitro and the organization of actin cytoskeleton in the pollen tube cell were investigated using a confocal laser scanning microscope after fluorescence labeling. Treatment with ion implantation significantly blocked pollen tube growth. Confocal microscopy showed that ion implantation disrupted actin filament cytoskeleton organization in the pollen tube. It was found that there was a distinct correlation between the inhibition of pollen tube growth and the disruption of actin cytoskeleton organization, indicating that an intact actin cytoskeleton is essential for continuous pollen tube elongation in Pinus thunbergii. Although the detailed mechanism for the ion-implantation-induced bioeffect still remains to be elucidated, the present study assumes that the cytoskeleton system in pollen grains may provide a key target in response to ion beam implantation and is involved in mediating certain subsequent cytological changes. 展开更多
关键词 ion implantation pollen tube CYTOSKELETON actin filament pinus thunbergii Parl
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Spatial geometric constraints histogram descriptors based on curvature mesh graph for 3D pollen particles recognition 被引量:1
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作者 谢永华 徐赵飞 Hans Burkhardt 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期123-130,共8页
This paper presents one novel spatial geometric constraints histogram descriptors (SGCHD) based on curvature mesh graph for automatic three-dimensional (3D) pollen particles recognition. In order to reduce high di... This paper presents one novel spatial geometric constraints histogram descriptors (SGCHD) based on curvature mesh graph for automatic three-dimensional (3D) pollen particles recognition. In order to reduce high dimensionality and noise disturbance arising from the abnormal record approach under microscopy, the separated surface curvature voxels are ex- tracted as primitive features to represent the original 3D pollen particles, which can also greatly reduce the computation time for later feature extraction process. Due to the good invariance to pollen rotation and scaling transformation, the spatial geometric constraints vectors are calculated to describe the spatial position correlations of the curvature voxels on the 3D curvature mesh graph. For exact similarity evaluation purpose, the bidirectional histogram algorithm is applied to the spatial geometric constraints vectors to obtain the statistical histogram descriptors with fixed dimensionality, which is invariant to the number and the starting position of the curvature voxels. Our experimental results compared with the traditional methods validate the argument that the presented descriptors are invariant to different pollen particles geometric transformations (such as posing change and spatial rotation), and high recognition precision and speed can be obtained simultaneously. 展开更多
关键词 pollen recognition curvature mesh graph spatial geometric constraints bidirectional histogram
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A Preliminary Study on DNA Mutation Induction of Maize Pollen Implanted by Low Energy N^+ Beam 被引量:3
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作者 程备久 阚显照 +1 位作者 朱苏文 李培金 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第1期659-664,共6页
The maize pollens were implanted with seven different doses of 30 keV N+ beam respectively, The genomic DNA polymorphism from treated pollens were analyzed with 104 primers by using RAPD respectively. The results sho... The maize pollens were implanted with seven different doses of 30 keV N+ beam respectively, The genomic DNA polymorphism from treated pollens were analyzed with 104 primers by using RAPD respectively. The results showed that N^+ beam-induced mutation of maize pollens can result in the change of their DNA bases. The mutation is not properly random and its frequency increases with a rise in 30 keV N+ beam doses. It is conformed with A-G transformation, which is one of the most important factors in DNA bases induced by N+ beam. 展开更多
关键词 DNA A Preliminary Study on DNA Mutation Induction of Maize pollen Implanted by Low Energy N BEAM
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Meiotic chromosome preparation techniques of pollen mother cells for laser micro-dissection in Populus spp. 被引量:1
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作者 YANG Hong-yan WANG Jun KANG Xiang-yang 《Forestry Studies in China》 CAS 2010年第2期74-78,共5页
In order to isolate meiotic chromosomes of Populus species meiotic chromosome preparation techniques of pollen mother cells for laser micro-dissection were studied. Pollen mother cells at diakinesis ofPopulus canadens... In order to isolate meiotic chromosomes of Populus species meiotic chromosome preparation techniques of pollen mother cells for laser micro-dissection were studied. Pollen mother cells at diakinesis ofPopulus canadensis Moench were used as samples. Two methods were used to prepare meiotic chromosomes: in the first, cell suspensions were dropped on polyethylene-naphthalate or polyester membrane slides which had just been incubated at -20~C; in the second method, cell suspensions were also dropped on polyethylene-naphthalate or polyester membrane slides, but spread with the aid of high temperatures. The cells did not completely spread by the first method and chromosomes at diakinesis could not be individually distinguished. In contrast, well-spread diakinesis chromosomes were obtained by the second method, where chromosomes, connected with their nucleolus, were successfully isolated with the laser micro-dissection system. As well, we discuss the prospect of applications of laser micro-dissection in cytogeneties and molecular genetics in Populus species. 展开更多
关键词 chromosomes diakinesis laser micro-dissection Populus spp. pollen mother cells
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Incidence and molecular markers of 2n pollen in Populus tomentosa Carr
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作者 ZHANG Zheng-hai KANG Xiang-yang ZHANG Ping-dong LI Yan-hua WANG Jun(Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, Beijing Forestry University) 《北京林业大学学报》 CAS CSCD 北大核心 2006年第S2期176-176,共1页
Microscopic examination and AFLP molecular markers were employed to determine the incidence and related markers of 2n pollen (unreduced pollen) in Populus tomentosa Carr. The parallel and tripolar spindle at metaphase... Microscopic examination and AFLP molecular markers were employed to determine the incidence and related markers of 2n pollen (unreduced pollen) in Populus tomentosa Carr. The parallel and tripolar spindle at metaphase Ⅱ and the absence of cytokinesis at telophase Ⅱ led to the formation of 2n pollen. A group of 298 clones came from their indigenous areas was investigated for the production of 2n pollen based on the pollen size differences, within a clone and between n and 2n pollen. Pollen grains of 224 clones were collected, six of them only produced normal pollen, and the rest produced 2n pollen at different frequencies (0.6% -21.9%). Clones producing six normal and 22 2n pollen were selected for AFLP analysis. Following an initial screening with 55 primer combinations, the E50-M38 (CAT/ACT) primer was identified, which generated a PCR fragment (246 bp) from the normal clones, but not from the 2n pollen producers. In addition, the E31-M50 (AAA/CAT) amplified DNA fragment (204 bp) that was present in 2n pollen producers, and absent in normal clones. Two polymorphic bands were found and they were distinguished between normal and 2n pollen clones. They are very useful as AFLP markers for molecular-assisted selection in triploid breeding of 2n gametes in P.tomentosa. 展开更多
关键词 AFLP POPULUS tomentosa Carr. MEIOSIS 2n pollen INCIDENCE TRIPLOID breeding
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Pollen morphology and trichome types of Betula spp. in the Hyrcanian forests of northern Iran
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作者 Vahide Payamnoor Ali Sattarian +1 位作者 Amir Kordalivand Jahangir Mohammadi 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第4期1191-1198,共8页
Pollen and trichome morphology of the genus Betula were evaluated from three main habitats in Iran using light and electron microscopy.Pollen types were identical and tri-porate;however,in terms of quantitative data,s... Pollen and trichome morphology of the genus Betula were evaluated from three main habitats in Iran using light and electron microscopy.Pollen types were identical and tri-porate;however,in terms of quantitative data,some differences were observed in exine(outside)wall thickness,length of polar axis and length of equatorial axis,possibly due to the environment.Pollen alone is insufficient to separate species of Iranian birch.Investigation of the trichome trait(small hairs or other outgrowths)revealed that birch species in Iran belong to:(1)Betula litwinowii Doluch.according to the low density of trichomes on the adaxial surface of the leaves and the lack of trichomes on the abaxial surface and many trichomes on the petioles;(2)Betula pendula Roth.due to the absence of trichomes on the adaxial surface and the low density of trichomes on the abaxial surface;and,(3)in the adaxial and abaxial surfaces of leaves and petioles,the trichomes had different types of pilose(long,soft hairs),and this strengthens the possibility of a different species or more likely a hybrid of B.pendula. 展开更多
关键词 BIRCH pollen morphology TRICHOME TYPES
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THE EFFECT OF LOW TEMPERATURE ADVERSITY ON MALE FLOWERS AND POLLEN IN LARIX OLGENSIS
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作者 魏占才 刘桂丰 +1 位作者 赵丽惠 李俊雁 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第4期8-13,共6页
The electrie conductivity of pollen life-force and male flowers of Larix olgensis on condition of low temperature adversity has been respectively measured by means of fluorescent dying method and conductivity method ... The electrie conductivity of pollen life-force and male flowers of Larix olgensis on condition of low temperature adversity has been respectively measured by means of fluorescent dying method and conductivity method in 1992 and 1994. The results indicate that:(1 ) If the same clonal pollen is treated at equal time at different low temperatures, there are significant differences in pollen life-force, the pollen life-force is the largest between O℃aild -3℃, in higher or lower temperature range, the pollen life-force will decrease. The measurement of electric conductivity of male flowers provcs that the low temperature of below -3℃ is the inain reason that the cell membrane is damaged and the pollen.life-force decreases. (2) The same clonal pollen life-force at the saine low temperature will gradually decrease with the increasing of frozen time. Its main reason is that suffocation and losing body fluid result in the damage of cell membrane, the measurement of electric conductivity of male flowers call prove that. (3) If pollen is treated with the same low temperature, the humidity will be the main factor of affecting pollen life-force. (4) There are significant differences in Larix olgensis's resistance against low temperature in its different growth stage, the male flower's resistance of near pollen spreading period is low. (5) The resistance is different within clones. (6) The resistance against low temperature of Larix call be incrcased by means of chemical treatment. 展开更多
关键词 Larix olgensis Male flower pollen RESISTANCE
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