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1.
J Agric Food Chem ; 72(20): 11746-11758, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38718253

RESUMEN

A novel strategy combining ferulic acid and glucose was proposed to reduce ß-lactoglobulin (BLG) allergenicity and investigate whether the reduction in allergenicity was associated with gut microbiome and serum metabolism. As a result, the multistructure of BLG changed, and the modified BLG decreased significantly the contents of IgE, IgG, IgG1, and mMCP-1 in serum, improved the diversity and structural composition of gut microbiota, and increased the content of short-chain fatty acids (SCFAs) in allergic mice. Meanwhile, allergic mice induced by BLG affected arachidonic acid, tryptophan, and other metabolic pathways in serum, the modified BLG inhibited the production of metabolites in arachidonic acid metabolism pathway and significantly increased tryptophan metabolites, and this contribution helps in reducing BLG allergenicity. Overall, reduced allergenicity of BLG after ferulic acid was combined with glucose modification by regulating gut microbiota, the metabolic pathways of arachidonic acid and tryptophan. The results may offer new thoughts alleviating the allergy risk of allergenic proteins.


Asunto(s)
Alérgenos , Ácidos Cumáricos , Microbioma Gastrointestinal , Glucosa , Lactoglobulinas , Ácidos Cumáricos/metabolismo , Ácidos Cumáricos/química , Animales , Lactoglobulinas/inmunología , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Ratones , Humanos , Alérgenos/inmunología , Alérgenos/química , Alérgenos/metabolismo , Glucosa/metabolismo , Femenino , Bacterias/inmunología , Bacterias/metabolismo , Bacterias/clasificación , Bacterias/genética , Ratones Endogámicos BALB C , Inmunoglobulina E/inmunología , Inmunoglobulina E/sangre , Ácidos Grasos Volátiles/metabolismo , Bovinos , Inmunoglobulina G/inmunología , Inmunoglobulina G/sangre , Hipersensibilidad a la Leche/inmunología
2.
J Agric Food Chem ; 71(41): 15363-15374, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37797215

RESUMEN

Ovalbumin (OVA) is a major allergen in hen eggs. Enzymolysis has been demonstrated as an efficient method for reducing OVA allergenicity. This study demonstrates that microwave pretreatment (MP) at 400 W for 20 s assisting bromelain enzymolysis further decreases the allergenicity of OVA, which was attributed to the increase in the degree of hydrolysis and promoted the destruction of IgE-binding epitopes. The results showed that MP could promote OVA unfolding, expose hydrophobic domains, and disrupt tightly packed α-helical structures and disulfide bonds, which increased the degree of hydrolysis by 7.28% and the contents of peptides below 1 kDa from 43.55 to 85.06% in hydrolysates compared with that for untreated OVA. Biological mass spectrometry demonstrated that the number of intact IgE-binding epitope peptides in MP-assisted OVA hydrolysates decreased by 533 compared to that in hydrolysis without MP; consequently, their IgG/IgE binding rates decreased more significantly. Therefore, MP-assisted enzymolysis may provide an alternative method for decreasing the OVA allergenicity.


Asunto(s)
Alérgenos , Pollos , Animales , Femenino , Ovalbúmina/química , Alérgenos/química , Pollos/metabolismo , Microondas , Péptidos , Espectrometría de Masas , Epítopos , Inmunoglobulina E/metabolismo
3.
Front Psychol ; 13: 951671, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36405188

RESUMEN

Objective: This study aimed to better understand the current situation involving work stressors and the coping styles of outpatient and emergency nurses in 29 pediatric specialty hospitals across China. The study analyzed this correlation to provide a reference for the occupational stress management of pediatric nurses. Methods: From June to September 2020, 1,457 outpatient and emergency nurses in 29 pediatric specialty hospitals across China were selected as study participants, and a questionnaire survey was conducted using the Basic Information Questionnaire, the Chinese version of the Work Stressor Scale for Nurses, and the Simple Coping Style Scale. Results: The assessed stress level of outpatient and emergency nurses in 29 tertiary pediatric specialty hospitals nationwide is lower than the results of the survey of the 2007 domestic norm, p < 0.05. The stressors related to nurses' expectations, family conflicts, the nature of nursing work, patient factors, and workload were lower compared with the national norm (p < 0.05). The positive coping style score on the Simple Coping Style Scale for pediatric outpatient nurses was (36.66 ± 6.16), and work stressors were positively associated with negative coping styles (p < 0.01). Multiple regression analysis showed that the influencing factors of work stressors among pediatric outpatient and emergency nurses correlated with the authorized size, age, working years of nurses, work department, and negative coping styles. Conclusion: Negative coping styles were present among pediatric outpatient and emergency nurses and were associated with work stressors. The influencing factors of stressors mainly correlated with the clinical establishment, age, years of employment as a nurse, work department, and negative coping styles.

4.
Food Chem ; 390: 133185, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35567971

RESUMEN

This study aimed to isolate and evaluate the allergenicity of glycated α-lactalbumin (ALA) digestive products and identify its allergenic peptides. The digestive products of native-, alone glycated- and ultrasound-assisted glycated ALA (ALA-D, ALA-gal-D, 100ALA-gal-D) were isolated into three fractions (F1, F2 and F3). High-resolution mass spectrometry showed that the digestion-resistant peptides of F2 and F3 mainly distributed in amino acid sequence (AA) 25-31, AA32-53, AA40-53, AA54-60, AA80-90, AA94-104. The allergenicity of the three fractions of glycated ALA was lower than that in ALA-D, indicating glycation of ALA could indeed reduce its allergenicity after digestion. Furthermore, most fractions isolated from high glycation-degree ALA had the lowest allergenicity. The IgG/IgE binding abilities of synthesized peptides indicated that AA94-104 firstly identified by us embodied the strongest allergenicity and might be the potential allergenic peptide. This will provide a theory for preparing hypoallergenic products based on the identified allergenic peptides.


Asunto(s)
Alérgenos , Lactalbúmina , Alérgenos/química , Glicosilación , Lactalbúmina/química , Espectrometría de Masas , Péptidos
6.
J Agric Food Chem ; 69(24): 6850-6859, 2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34114451

RESUMEN

Physical-assisted chemical modification is effective to reduce the allergenicity of α-lactalbumin (ALA). However, there are few in-depth studies on the allergenicity changes of physical-assisted chemical-modified ALA during digestion. The effect of gastroduodenal digestion on the allergenicity changes of ALA treated by sonication-assisted glycation was assessed. Digestion of both ALA and its glycated forms generated peptide fractions, and intact undigested glycated ALA in the hydrolysates still covalently bound to d-galactose. High-resolution mass spectrometry revealed that a higher glycation degree was discovered in sonication-preprocessed ALA compared to native ALA. Enzyme-linked immunosorbent assay and basophil degranulation showed that sonication-assisted glycation could significantly reduce ALA allergenicity. The allergenicity of both gastric and gastroduodenal hydrolysates was further increased, and the hydrolysates of sonication-assisted glycated ALA showed the lowest allergenicity. The reason could be the shielding effect of the linear epitope found to be caused by a higher glycation degree; although linear epitopes were exposed, d-galactose covalently bound to intact undigested glycated ALA in the hydrolysates retained its masking role. These results indicated that sonication-assisted glycation could be a promising method to prepare immunotherapeutic agents for allergen immunotherapy to achieve the purpose of allergy desensitization.


Asunto(s)
Alérgenos , Lactalbúmina , Digestión , Inmunoglobulina E , Sonicación
7.
J Agric Food Chem ; 69(12): 3741-3750, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33739097

RESUMEN

Glycation between proteins and reducing sugars is the common chemical modification in food protein, and many studies have focused on the allergenicity of the glycated protein. However, a systemic study on the allergenicity change of its digests is lacking. In this work, we explored the change rule of the digestibility and allergenicity of glycated ß-Lg during in vitro gastrointestinal digestion and interpreted the mechanism using high-resolution mass spectrometry. Glycation with arabinose increased the resistance of ß-Lg to digestive enzyme, with a low hydrolysis value. Indirect competitive ELISA showed that the IgG/IgE binding rates of ß-Lg were reduced after glycation and further reduced after digestion, in comparison with the digests of unglycated ß-Lg. There are two reasons for this phenomenon. On the one hand, 11 glycated sites were determined in the lowest allergenicity arabinose-ß-Lg conjugation (Ara-ß-Lg), which was distributed in the IgG and IgE linear allergic epitopes of ß-Lg. On the other hand, glycation masking linear allergenic epitopes had a more significant effect on reducing allergenicity in comparison to digestive enzyme hydrolysis. These results indicated that the allergenicity of Ara-ß-Lg in the human body might be lower than that of unglycated ß-Lg.


Asunto(s)
Alérgenos , Lactoglobulinas , Humanos , Inmunoglobulina E , Inmunoglobulina G , Espectrometría de Masas
8.
Sci Rep ; 11(1): 664, 2021 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-33437022

RESUMEN

Sanwei-Tanxiang powder (SWTX), a traditional Mongolian and Tibetan medicine containing a cocktail of active molecules, relieves angina pectoris and improves recovery in patients with coronary heart disease (CHD). The pharmacological effect of SWTX on CHD was analyzed at a systemic point of view in our previous studies. The bioinformatics prediction showed that the PI3K/Akt/FoxO3a pathway was one of important pathways of SWTX on treatment of coronary heart disease. Based on it, the aim of this study was to evaluate the benefits of SWTX in acute myocardial ischemic-reperfused (MIR) rat in vivo and H9c2 cardiomyoblast cells under oxidative stress induced by H2O2 in vitro, and further investigate the involvement of PI3K/Akt/FoxO3a pathway in these processes. Ex vivo, under physiological conditions, SWTX did not show any modification in the heart rate and contraction amplitude. However, against a MIR injury, SWTX pretreatment provided significant protection, including reduced ST-segment elevation, pathological changes and myocardial infarct size in vivo, meanwhile, some monomers of SWTX showed antioxidant capacity and inhibited cardiomyocytic apoptosis in vitro. The effect was correlated with the activation of the PI3K/Akt/FoxO3a signaling pathway downstream and the regulation of downstream pro-apoptotic Bim of FoxO3a experimental verified by qRT-PCR, Western blot and immunofluorescent assay. In vitro, blocking Akt and p-FoxO3a activation with the PI3K inhibitor LY294002 effectively suppressed the protective effects of several active monomers (including quercetin, macelignan,methyleugenol and Santol) of SWTX against H2O2-induced injury. Collectively, these results suggest that SWTX decreases I/R injury, and the PI3K/Akt/FoxO3a pathway takes part in protection during this process, gallogen (G3) and quercetin (G8) of GZ, methyleugenol (R2) and macelignan (R7) of RDK, santol (T1) of TX are responsible at least in part for SWTX's cardioprotection effect.


Asunto(s)
Cardiotónicos/farmacología , Medicamentos Herbarios Chinos/farmacología , Daño por Reperfusión Miocárdica/prevención & control , Polvos/farmacología , Animales , Apoptosis , Combinación de Medicamentos , Masculino , Daño por Reperfusión Miocárdica/etiología , Daño por Reperfusión Miocárdica/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal
9.
Mol Ecol ; 29(10): 1791-1805, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32306487

RESUMEN

Allopatric divergence is often initiated by geological uplift and restriction to sky-islands, climate oscillations, or river capture. However, it can be difficult to establish which mechanism was the most likely to generate the current phylogeographical structure of a species. Recently, genomic data in conjunction with a model testing framework have been applied to address this issue in animals. To test whether such an approach is also likely to be successful in plants, we used population genomic data of the Rheum palmatum complex from the Eastern Asiatic Region, in conjunction with biogeographical reconstruction and demographic model selection, to identify the potential mechanism(s) which have led to the current level of divergence. Our results indicate that the R. palmatum complex originated in the central Hengduan Mts and possibly in regions further east, and then dispersed westward and eastward resulting in genetically distinct lineages. Populations are likely to have diverged in refugia during climate oscillations followed by subsequent expansion and secondary contact. However, model simulations within the western lineage of the R. palmatum complex cannot reject a restriction to sky-islands as a possible mechanism of diversification due to the genetically ambiguous position of one population. This highlights that genetically mixed populations might introduce ambiguity regarding the best diversification model in some cases. Although it might be possible to resolve this ambiguity using other data, sometimes this could prove to be difficult in complex biogeographical areas.


Asunto(s)
Evolución Biológica , Genética de Población , Rheum/genética , Asia Oriental , Islas , Filogenia , Filogeografía
10.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(4): 2935-6, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26153751

RESUMEN

The complete chloroplast genome of the medicinal plant Rheum palmatum L. (Polygonaceae) has been reconstructed from the whole-genome Illumina sequencing data. The genome is 161 541 bp in length, and exhibits a typical quadripartite structure of the large (LSC, 86 518 bp) and small (SSC, 13 111 bp) single-copy regions, separated by a pair of inverted repeats (IRs, 30 956 bp each). The chloroplast genome contains 131 genes, including 84 protein-coding genes (78 PCG species), eight ribosomal RNA genes (four rRNA species) and 37 transfer RNA genes (28 tRNA species). Phylogenetic tree based on the maximum parsimony (MP) analysis of 65 chloroplast protein-coding genes for 13 taxa demonstrated a close relationship between R. palmatum and Fagopyrum esculentum subsp. ancestrale in Polygonaceae.


Asunto(s)
Genoma del Cloroplasto , Rheum/clasificación , Rheum/genética , Composición de Base , Genes del Cloroplasto , Genes de Plantas , Tamaño del Genoma , Sistemas de Lectura Abierta , Filogenia , Plantas Medicinales/clasificación , Plantas Medicinales/genética , Análisis de Secuencia de ADN , Secuenciación Completa del Genoma
11.
Zhong Yao Cai ; 38(3): 467-72, 2015 Mar.
Artículo en Chino | MEDLINE | ID: mdl-26495643

RESUMEN

OBJECTIVE: To predict the distribution patterns of the original plants of Rhei Radix et Rhizoma current and in future in China under climate change. METHODS: A maximum entropy modeling and variety of climate change scenarios were employed to predict its current and future distribution ranges in China. RESULTS: The resultant models exhibited excellent predictive power. The current suitable habitats for original plants of Rhei Radix et Rhizoma totaled 84. 20 x 10(4) km2 accounting for 8. 77% of the total area of China; 57. 05% of its current suitable habitats(i. e. low impact areas) would be relatively lowly impacted by the climate change. Compared with its current distribution pattern,its distribution ranges during 2020s, 2030s, 2040s, 2050, 2060s, 2070s and 2080s would be shrunk to some extent. However, the moderately suitable area would be expanded to a certain degree. CONCLUSION: Climate change has a negative impact on the total area and the habitat suitability for the original plants of Rhei Radix et Rhizoma.


Asunto(s)
Cambio Climático , Ecosistema , Rheum/crecimiento & desarrollo , China , Raíces de Plantas , Plantas Medicinales/crecimiento & desarrollo , Rizoma
12.
PLoS One ; 9(10): e110760, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25349989

RESUMEN

AIMS: Rheum palmatum complex comprises all taxa within section Palmata in the genus Rheum, including R. officinale, R. palmatum, R. tanguticum, R. tanguticum var. liupanshanense and R. laciniatum. The identification of the taxa in section Palmata is based primarily on the degree of leaf blade dissection and the shape of the lobes; however, difficulties in species identification may arise from their significant variation. The aim of this study is to analyze the patterns of variation in leaf blade characteristics within and among populations through population-based sampling covering the entire distribution range of R. palmatum complex. METHODS: Samples were taken from 2340 leaves from 780 individuals and 44 populations representing the four species, and the degree of leaf blade dissection and the shape of the lobe were measured to yield a set of quantitative data. Furthermore, those data were statistically analyzed. IMPORTANT FINDINGS: The statistical analysis showed that the degree of leaf blade dissection is continuous from lobed to parted, and the shape of the lobe is also continuous from broadly triangular to lanceolate both within and between populations. We suggested that taxa in section Palmata should be considered as one species. Based on the research on the R. palmatum complex, we considered that the quantitative characteristics were greatly influenced by the environment. Therefore, it is not reliable to delimitate the species according to the continuously quantitative vegetative characteristics.


Asunto(s)
Hojas de la Planta/anatomía & histología , Rheum/anatomía & histología , Ambiente , Geografía , Fenotipo
13.
PLoS One ; 9(7): e101362, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24988081

RESUMEN

AIMS: Fargesia decurvata is closely allied with F. dracocephala and differs in 5 major characters (i.e. the culm sheath blade base shape, the width of the culm sheath blade base, the auricle shape, and the lower surface of leaf blade) in Fargesia. It is difficult to distinguish these two species because of existing of transitional statements of characters. The aims of this paper are to (i) investigate whether the variation of the characters is continuous or not; (ii) reveal whether the publishment of F. dracocephala was the result of discontinuous sampling of F. decurvata or not. METHODS: Ten populations of F. decurvata and F. dracocephala were investigated in their entire distribution (including type localities). The statements of 5 major characters were measured from 693 annual and 693 perennial culms of 231 individuals in 10 populations, and analyzed at population, individual and culm levels. UPGMA cluster analysis was carried out based on 29 characters from 10 populations of F. decurvata and F. dracocephala and 2 populations of F. qinlingensis as outgroup. The ITS sequences were also sequenced and analyzed. IMPORTANT FINDINGS: Five major characters exhibited great variation not only at population level, but at individual level within a population, even the culm level within an individual and in different parts of the same culm. Cluster analyses showed that 10 populations of F. decurvata and F. dracocephala were not divided into two species, but they were well separated with outgroup. There was no difference in floral organ between F. decurvata and F. dracocephala. MP and NJ trees based on ITS sequences showed the same results with the cluster analysis on morphological characters. All the facts indicated that the publishment of F. dracocephala was the result of discontinuous sampling of F. decurvata, and F. dracocephala should be treated as the synonym of F. decurvata.


Asunto(s)
Poaceae/anatomía & histología , Poaceae/genética , Análisis por Conglomerados , ADN de Plantas/genética , ADN Espaciador Ribosómico/genética , Hojas de la Planta/anatomía & histología , Hojas de la Planta/clasificación , Hojas de la Planta/genética , Poaceae/clasificación , Análisis de Secuencia de ADN
14.
Zhonghua Nan Ke Xue ; 19(3): 223-7, 2013 Mar.
Artículo en Chino | MEDLINE | ID: mdl-23700727

RESUMEN

OBJECTIVE: To investigate the impact of infertility on men's self-esteem, self-confidence, sexual satisfaction and overall relationship with their spouses. METHODS: Using Self-Esteem and Relationship questionnaire (SEAR), we conducted an investigation among 253 infertile men and 52 fertile male controls. We divided the infertile men into four subgroups according to their perceived causes of infertility: male (M) factors, female (F) factors, both M and F factors, and unknown factors, and compared the SEAR scores among different groups. RESULTS: In the infertile men, the total SEAR score was significantly higher in those with < 3 years than in those with > or = 3 years of infertility duration (75.50 +/- 17.05 vs 68.66 +/- 17.19, P < 0.05) and so was it in those with above-high-school than in those with high-school or lower education background (81.42 +/- 13.99 vs 67.61 +/- 17. 8, P < 0.01), but showed no significant difference between the > or = 30- and < 30-year-olds (71.77 +/- 17.42 vs 72.74 +/- 18.38, P > 0.05). The total SEAR scores in the M factor, M & F factor, unknown factor and F factor groups were 65.69 +/- 18.68, 68.52 +/- 17.68, 74.85 +/- 15.19 and 83.21 +/- 12.61, respectively, with significant differences between the first two and the latter two groups (P < 0.05), as well as between the unknown factor and F factor groups (P < 0.05). In the fertile male controls, the total SEAR score and subdomain scores on sexual relationship, self-confidence, self-esteem and overall relationship were 90.04 +/- 9.85, 88.40 +/- 10.74, 92.23 +/- 9.41, 91.95 +/- 10.67 and 90.38 +/- 14.14, respectively, all remarkably higher than in the M factor, M&F factor and unknown factor groups of the infertile men after adjustment of their infertility duration and education levels (P < 0.05). CONCLUSION: Infertility reduces men's self-esteem, self-confidence, sexual satisfaction and relationship with their spouses, and the degree of its impact is correlated with the patients' infertility duration and education level.


Asunto(s)
Infertilidad Masculina/psicología , Satisfacción Personal , Autoimagen , Adulto , Disfunción Eréctil/psicología , Humanos , Masculino , Encuestas y Cuestionarios
15.
Zhonghua Nan Ke Xue ; 19(12): 1087-90, 2013 Dec.
Artículo en Chino | MEDLINE | ID: mdl-24432619

RESUMEN

OBJECTIVE: To evaluate the impact of the factors of perceived male infertility on men's penile erectile function. METHODS: Using the 5-item version of the International Index of Erectile Function (IIEF-5), we investigated the penile erectile function among 245 infertile men (infertility group) and another 52 males having physical checkup for planned conception (checkup group), the former further divided into four subgroups according to the factors of infertility: male factor, female factor, bilateral factor, and unknown factor. We compared the total and item scores of IIEF-5 among different groups. RESULTS: Mild or mild-moderate ED was found in 50.61% of the infertile men, with a total IIEF-5 score of 21.24 +/- 2.58. The total and item scores of IIEF-5 were markedly higher in the male factor than in the female factor subgroup (P < 0.01), but with no significant difference between the male factor subgroup and the bilateral and unknown factor subgroups (P > 0.05), except the score on confidence. The scores were significantly lower in the bilateral and unknown factor subgroups than in the female factor subgroup (P < 0.05), with no remarkable difference between the former two. In the infertility group, the total and item scores of IIEF-5 were markedly higher in those with education above high school than in those with high school or lower education (P < 0.01), but not correlated with age and infertility duration. After adjustment for education background, the total IIEF-5 score and the scores on confidence and satisfaction were significantly lower in the infertility than in the checkup group (P < 0.05), and 15.38% of the men in the latter group had mild ED, dramatically lower than in the former (P < 0.01). CONCLUSION: Perceived infertility may cause ED in males, and a higher incidence rate is associated with lower education background of the men.


Asunto(s)
Disfunción Eréctil/epidemiología , Infertilidad Masculina/fisiopatología , Pene/fisiopatología , Adulto , Humanos , Masculino , Erección Peniana , Encuestas y Cuestionarios , Adulto Joven
16.
Int J Mol Sci ; 13(3): 3900-3915, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22489188

RESUMEN

Rheum officinale Baill., an important but endangered medicinal herb, is endemic to China. Inter-simple sequence repeat (ISSR) markers were employed to investigate the genetic diversity and differentiation of 12 populations of R. officinale. Thirteen selected primers yielded 189 bright and discernible bands, with an average of 14.54 per primer. The genetic diversity was low at the population level, but pretty high at the species level (H = 0.1008, I = 0.1505, PPB = 28.95% vs. H = 0.3341, I = 0.5000, PPB = 95.24%, respectively) by POPGENE analysis. Analysis of molecular variance (AMOVA) showed that the genetic variation was found mainly among populations (74.38%), in line with the limited gene flow (N(m) = 0.2766) among populations. Mantel test revealed a significant correlation between genetic and geographic distances (r = 0.5381, P = 0.002), indicating the role of geographic isolation in shaping the present population genetic structure. Both Bayesian analysis and UPGMA cluster analysis demonstrated the similar results. Our results imply that the conservation efforts should aim to preserve all the extant populations of this endangered species, and cultivation is proposed in this study.


Asunto(s)
Repeticiones de Microsatélite/genética , Aislamiento Reproductivo , Rheum/genética , Secuencia de Bases , Análisis por Conglomerados , Cartilla de ADN/genética , Flujo Génico , Variación Genética , Genética de Población , Geografía , Plantas Medicinales/genética , Rheum/clasificación , Análisis de Secuencia de ADN
17.
Ann Bot ; 109(6): 1125-32, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22401850

RESUMEN

BACKGROUND AND AIMS: Preliminary field observations in 2001 and 2002 suggested that Kingdonia uniflora (Circaeasteraceae, Ranunculales) exhibits heterodichogamy, an unusual kind of reproductive heteromorphy, hitherto unreported in Ranunculales and known from only one other genus in basal eudicots. METHODS: During several subsequent years flowers were observed in the field. Flowers were fixed in FAA and studied with microtome sections series and with the scanning electron microscope. KEY RESULTS: The flowers proved to be heterodichogamous, with protandrous and protogynous morphs, which have a 1 : 1 ratio. Both morphs equally set fruit. Each year a single flower is formed at the tip of a rhizome or more rarely two flowers. The flowers are already open when they appear at the soil surface, before they are receptive and before pollen is dispersed. In both floral morphs the styles elongate early and the stigmas are positioned above the anthers before anthesis begins. In protogynous flowers the stigmas become receptive in this position; later the styles become reflexed and then the anthers dehisce. In contrast, in protandrous flowers the stamen filaments elongate during early anthesis such that the dehiscing anthers come to lie above the (still unreceptive) stigmas; after dehiscence of all anthers in a flower the styles begin to elongate and become receptive. CONCLUSIONS: This is the first record of heterodichogamy in a representative of Ranunculales, in an herbaceous eudicot, and in a plant with uniflorous ramets. The occurrence of heterodichogamy in Kingdonia in which clonal reproduction appears to be dominant might be an adaptation to avoid mating between the ramets from a common mother individual (genet).


Asunto(s)
Flores/fisiología , Flores/ultraestructura , Organismos Hermafroditas/clasificación , Organismos Hermafroditas/fisiología , Magnoliopsida/clasificación , Magnoliopsida/fisiología , China , Reproducción
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