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1.
Analyst ; 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33599635

RESUMO

Nanoparticles are often used to serve as drug delivery systems to improve the therapeutic efficacy of some hydrophobic drugs. In this work, PEG and peptide-modified titanium phosphate nanoparticles (TiP-PEG/peptide) were synthesized to enhance the drug delivery efficacy of tirucalla-8,24-diene-3ß,11ß-diol-7-one (KS-01), a major bioactive and hydrophobic component extracted from Euphorbia kansui. This drug delivery system with a loading efficiency of about 29.8 mg KS-01/1 g TiP-PEG/peptide exerted a significantly lower cell viability rate of MCF-7 than free KS-01, indicating that these carriers can effectively increase the therapeutic efficacy by improving its water solubility. Moreover, according to the fluorescence intensity of FAM which can be generated by caspase-3 cleaving DEVD-embedded peptide, the caspase-3 level could be determined and the therapeutic efficacy could be visualized in real time.

2.
J Pharm Biomed Anal ; 195: 113828, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33349474

RESUMO

The dried roots of Euphorbia kansui (EK) are especially beneficial for the treatment of edema, but the severe toxicity limits their clinical applications. Euphorbia kansui stir-fried with vinegar (VEK) is traditionally employed to reduce the toxicity of EK. However, the material basis for the toxicity reduction with effectivity conservation is still unclear. Therefore, in this study, a rapid, sensitive, and reliable ultra-fast liquid chromatography tandem mass spectrometry (UFLC-MS/MS) method was firstly established to simultaneously determine six ingenane-type diterpenoids, i.e. kansuiphorin C (1), 5-O-benzoyl-20-deoxyingenol (2), 20-deoxyingenol (3), 3-O-(2'E,4'E-decadienoyl)-20-O-acetylingenol (4), 20-O-(2'E,4'Z-decadienoyl)ingenol (5), and ingenol (6), in EK and VEK based on the processing conversion. Then, the toxicity evaluation on zebrafish embryos and modulation of the expression of aquaporin-3 (AQP3) proteins in HT-29 cells were employed to investigate the toxicity-activity of six compounds. Chromatographic separation was obtained on Waters BEH RP18 column (2.1 mm × 100 mm, 2.5 µm) with the mobile phase composed of 0.1 % formic acid in acetonitrile and water, respectively. The column temperature was 35 ℃ at a flow rate of 0.4 mL min-1. Multiple reaction monitoring was conducted in both positive and negative modes for quantitative analysis. The method was then successfully used for the determination of six compounds in EK and VEK. In addition, 1, 2, 4, and 5 had evident cardiotoxicity, intestinal irritation and nutrient absorption disorders on zebrafish larvae, while no in-vivo toxicity was seen for groups given 3 and 6 (LC50 > 200 µM). Meanwhile, 1, 2, 4, 5, and 6 significantly increased the expression of AQP3 protein (p < 0.05) to promote the excretion of water in the colon. This study demonstrated that toxic ingenane-type diterpenoids converted into the less toxic compounds with the same core structure through the breakage of multiple ester bonds in the side chain. At the same time, the laxative effect was retained, providing useful information for the optimization of the process of EK and quality evaluation of other similar toxic Chinese herbal medicines.

3.
Sci Total Environ ; 748: 141375, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113681

RESUMO

Storm runoff is important for maintaining surface water resources, while this function is significantly affected by land use and land cover changes, e.g., afforestation and reforestation. The Chinese Loess Plateau (CLP) has undergone large-scale vegetation rehabilitation, especially afforestation over the past 20 years. We hypothesize that afforestation has profoundly changed the amounts and mechanisms of storm runoff generation in headwater catchments on the CLP. To test this hypothesis, rainfall, soil moisture, and streamflow were monitored in a grass catchment and an adjacent forest catchment for two consecutive years. The objective of this study was to elucidate the varied mechanisms of storm runoff generation in these two contrasting revegetated catchments. Results showed that (1) average runoff coefficient in the grassland catchment (0.042) was approximately ten times higher than that in the forestland catchment (0.004), confirming the impact of catchment afforestation on the suppression of storm runoff generation. (2) Peak rainfall intensity was the first-order control of the runoff coefficient in the grassland catchment, but not in the forestland catchment. (3) Threshold values for antecedent soil moisture (~18%) and the sum of antecedent soil moisture index and event precipitation (~210 mm) were identified in the grassland catchment, above which storm runoff significantly increased. (4) Two extraordinary high runoff coefficient events were observed in the grassland catchment, one due to high peak rainfall intensity and strong surface runoff and the other due to high rainfall amount and high antecedent soil moisture. We conclude that long-term afforestation has changed the mechanisms and patterns of storm runoff generation, and different conditions of rainfall intensity, rainfall amount and antecedent soil moisture determined the hydrological connectivity between the upper hillslope and downhill gully in the catchment. This study deepens our understanding of the mechanisms and thresholds of storm runoff generation in headwater catchments on the CLP.


Assuntos
Chuva , Movimentos da Água , Hidrologia , Poaceae , Solo
4.
Opt Express ; 28(20): 28819-28830, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114792

RESUMO

We present a reference-free method to determine electrical parameters of thin conducting films by steady state transmission-mode terahertz time-domain spectroscopy (THz-TDS). We demonstrate that the frequency-dependent AC conductivity of graphene can be acquired by comparing the directly transmitted THz pulse with a transient internal reflection within the substrate which avoids the need for a standard reference scan. The DC sheet conductivity, scattering time, carrier density, mobility, and Fermi velocity of graphene are retrieved subsequently by fitting the AC conductivity with the Drude model. This reference-free method was investigated with two complementary THz setups: one commercial fibre-coupled THz spectrometer with fast scanning rate (0.2-1.5 THz) and one air-plasma based ultra-broadband THz spectrometer for greatly extended frequency range (2-10 THz). Certain propagation correction terms for more accurate retrieval of electrical parameters are discussed.

5.
Int J Mol Sci ; 21(11)2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32517095

RESUMO

In contrast to typical radially symmetrical flowers, zygomorphic flowers, such as those produced by pea (Pisum sativum L.), have bilateral symmetry, manifesting dorsoventral (DV) and organ internal (IN) asymmetry. However, the molecular mechanism controlling IN asymmetry remains largely unclear. Here, we used a comparative mapping approach to clone SYMMETRIC PETALS 1 (SYP1), which encodes a key regulator of floral organ internal asymmetry. Phylogenetic analysis showed that SYP1 is an ortholog of Arabidopsis thaliana LIGHT-DEPENDENT SHORT HYPOCOTYL 3 (LSH3), an ALOG (Arabidopsis LSH1 and Oryza G1) family transcription factor. Genetic analysis and physical interaction assays showed that COCHLEATA (COCH, Arabidopsis BLADE-ON-PETIOLE ortholog), a known regulator of compound leaf and nodule identity in pea, is involved in organ internal asymmetry and interacts with SYP1. COCH and SYP1 had similar expression patterns and COCH and SYP1 target to the nucleus. Furthermore, our results suggested that COCH represses the 26S proteasome-mediated degradation of SYP1 and regulates its abundance. Our study suggested that the COCH-SYP1 module plays a pivotal role in floral organ internal asymmetry development in legumes.

6.
Nano Lett ; 20(3): 2107-2112, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32053385

RESUMO

We report a chemical route to synthesize centimeter-scale stoichiometric "graphenol (C6OH1)", a 2D crystalline alcohol, via vapor phase hydroxylation of epitaxial graphene on Cu(111). Atomic resolution scanning tunneling microscopy revealed this highly-ordered configuration of graphenol and low energy electron diffraction studies on a large-area single crystal graphene film demonstrated the feasibility of the same superstructure being achieved at the centimeter length scale. Periodic density functional theory (DFT) calculations about the formation of C6(OH)1 and its electronic structure are also reported.

7.
Sci Rep ; 10(1): 647, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959776

RESUMO

Accumulating evidence suggests AKT1 and DRD2-AKT-GSK3 signaling involvement in schizophrenia. AKT1 activity is also required for lithium, a GSK3 inhibitor, to modulate mood-related behaviors. Notably, GSK3 inhibitor significantly alleviates behavioral deficits in Akt1-/- female mice, whereas typical/atypical antipsychotics have no effect. In agreement with adjunctive therapy with lithium in treating schizophrenia, our data mining indicated that the average utilization rates of lithium in the Taiwan National Health Insurance Research Database from 2002 to 2013 are 10.9% and 6.63% in inpatients and outpatients with schizophrenia, respectively. Given that lithium is commonly used in clinical practice, it is of great interest to evaluate the effect of lithium on alleviating Akt1-related deficits. Taking advantage of Akt1+/- mice to mimic genetic deficiency in patients, behavioral impairments were replicated in female Akt1+/- mice but were alleviated by subchronic lithium treatment for 13 days. Lithium also effectively alleviated the observed reduction in phosphorylated GSK3α/ß expression in the brains of Akt1+/- mice. Furthermore, inhibition of Akt expression using an Akt1/2 inhibitor significantly reduced neurite length in P19 cells and primary hippocampal cell cultures, which was also ameliorated by lithium. Collectively, our findings implied the therapeutic potential of lithium and the importance of the AKT1-GSK3 signaling pathway.


Assuntos
Bases de Dados Factuais , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Seguro Saúde , Compostos de Lítio/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/genética , Transdução de Sinais , Adolescente , Adulto , Idoso , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Humanos , Compostos de Lítio/farmacologia , Masculino , Camundongos , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Taiwan , Adulto Jovem
8.
BMC Plant Biol ; 19(1): 495, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31726995

RESUMO

BACKGROUND: The interaction among plants and their pollinators has been a major factor which enriched floral traits known as pollination syndromes and promoted the diversification of flowering plants. One of the bee-pollination syndromes in Faboideae with keel blossoms is the formation of a landing platform by wing and keel petals. However, the molecular mechanisms of elaborating a keel blossom remain unclear. RESULTS: By performing large scale mutagenesis, we isolated and characterized a mutant in Vigna radiata, love on wings (low), which shows developmental defects in petal asymmetry and vasculature, leading to a failure in landing platform formation. We cloned the locus through map-based cloning together with RNA-sequencing (RNA-seq) analysis. We found that LOW encoded a nucleus-localized Dof-like protein and was expressed in the flower provascular and vascular tissues. A single copy of LOW was detected in legumes, in contrast with other taxa where there seems to be at least 2 copies. Thirty one Dof proteins have been identified from the V. radiata's genome, which can be further divided into four Major Cluster of Orthologous Groups (MCOGs). We also showed that ectopic expression of LOW in Arabidopsis driven by its native promoter caused changes in petal vasculature pattern. CONCLUSIONS: To summarize, our study isolated a legume Dof-like factor LOW from V. radiata, which affects vasculature development in this species and this change can, in turn, impact petal development and overall morphology of keel blossom.


Assuntos
Flores/fisiologia , Proteínas de Plantas/fisiologia , Vigna/fisiologia , Arabidopsis/genética , Fabaceae/genética , Flores/anatomia & histologia , Genes de Plantas , Mutagênese , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Polinização , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Vigna/anatomia & histologia , Vigna/genética
9.
Aust J Rural Health ; 27(6): 535-541, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31614059

RESUMO

OBJECTIVE: To investigate the urban-rural disparities in health risk factors, health status and outcomes in Tianjin, China and to make an international comparison with urban-rural health in Australia. DESIGN: A descriptive analytical cross-sectional survey. SETTING: Mobile research teams conducted door-to-door field surveys of each house or department. The teams included local administrative staff and Tianjin Center for Disease Control and Prevention's epidemiologists, clinicians and laboratory technicians. PARTICIPANTS: A total of 25 288 residents were interviewed and clinically observed, including 8583 urban residents and 16 705 rural residents. MAIN OUTCOME MEASURE: Health risk factors, health status and outcomes. RESULTS: The age structure in urban areas of Tianjin was growing older. Rural residents received less high school education and university education than did urban residents. Urban residents had higher medical insurance coverage and paid more out-of-pocket medical expenditures than did rural residents. The prevalence of smoking and the crude alcohol consumption rate were higher in rural areas than in urban areas. Rural residents had feelings of higher self-satisfaction concerning their health status than did urban residents. The prevalence of hypertensive disease, type 2 diabetes and heart, stroke and vascular diseases were significantly lower in rural areas than in urban areas. The incidence rate of serious injuries resulting from traffic accidents was significantly higher in rural areas than in urban areas. CONCLUSION: Contrary to Australian urban-rural survey outcomes, the health status and outcomes of residents in rural areas of Tianjin seemed to be better than those of their counterparts in urban areas. The underlying determinants of these outcomes need to be explored with further study.


Assuntos
Nível de Saúde , Avaliação de Resultados em Cuidados de Saúde/tendências , População Rural , População Urbana , China , Doença Crônica/epidemiologia , Estudos Transversais , Financiamento Pessoal , Comportamentos Relacionados com a Saúde , Inquéritos Epidemiológicos , Humanos , Seguro Saúde , Entrevistas como Assunto , Pesquisa Qualitativa
10.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3376-3384, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621223

RESUMO

We examined the effects of different salt stress intensities (control, mild, moderate, severe) on the growth traits, photosynthetic and fluorescence characteristics, and root architecture of three Corylus heterophylla × C. avellan varieties (Xinzhen 1, Xinzhen 2, Xinzhen 3). The results showed that the new shoot length, basal diameter, leaf area, root biomass, shoot biomass, leaf biomass, and total biomass of the three varieties all decreased, but the root-shoot ratio increased with increasing salt stress. The net photosynthetic rate of the three varieties in the moderate and severe salt stress treatments significantly decreased by 20.5% and 43.2%, respectively. The transpiration rate and stomatal conductance in the mild, moderate, and severe salt stress treatments decreased by 2.0%, 16.3%, 32.0% and 10.2%, 35.7%, 60.1% than those of the control, respectively. With the increasing salt stress, the intercellular CO2 concentration gradually increased, while the water use efficiency increased first and then decreased and being the highest in the mild salt stress treatment. The initial fluorescence of the three varieties increased with the increasing salt stress. With the increasing salt stress, the maximum fluorescence, maximal photochemical efficiency, potential photochemical activity, actual photochemical efficiency, electron transfer rate and photochemical quenching coefficient decreased, while the non-photochemical quenching coefficient increased first and then decreased. Salt stress reduced root biomass, length, surface area and volume of the three varieties. In the same salt stress treatment, the reduction of root architecture parameters of Xinzhen 2 was lower than the other two varieties. The growth traits, photosynthetic and fluorescence characteristics, and root architecture parameters of Corylus heterophylla × C. avellan were affected by both varieties and salt stress. Xinzhen 2 displayed stronger growth and photosynthetic physiological adaptability to salt stress, showing stronger salt tolerance than the other two varieties.


Assuntos
Corylus , Plântula , Fluorescência , Fotossíntese , Estresse Salino , Estresse Fisiológico
11.
Development ; 146(16)2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31391196

RESUMO

Flowers of honey plants (Torenia) face various abiotic stressors, including rain, that can damage pollens and dilute nectar. Many Torenia species are thought to have evolved a modified corolla base termed the corolla neck to prevent raindrops from contacting the nectar. Although this hypothesis was postulated long ago, direct validation is lacking. Here, we have evaluated Torenia fournieri, the corolla tube of which differentiates into distinct regions: a conical tube above that connects to an inflated base through a constriction. This constriction and inflated base are collectively referred to as the corolla neck. Using transcriptomic sequencing and genome-editing approaches, we have characterized an ALOG gene, TfALOG3, that is involved in formation of the corolla neck. TfALOG3 was found expressed in the epidermis of the corolla neck. Cells in the corolla bottom differentiated and expanded in wild-type T. fournieri, whereas such cells in TfALOG3 loss-of-function mutants failed to develop into a corolla neck. Water easily contacted the nectary in the absence of the corolla neck. Taken together, our study unveils a novel gene that controls corolla tube differentiation and demonstrates a hypothetical property of the corolla neck.


Assuntos
Flores/anatomia & histologia , Genes de Plantas , Lamiales/anatomia & histologia , Diferenciação Celular , Flores/citologia , Flores/crescimento & desenvolvimento , Lamiales/citologia , Lamiales/genética , Mutação com Perda de Função , Família Multigênica
12.
Adv Mater ; 31(35): e1903615, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31264306

RESUMO

To date, thousands of publications have reported chemical vapor deposition growth of "single layer" graphene, but none of them has described truly single layer graphene over large area because a fraction of the area has adlayers. It is found that the amount of subsurface carbon (leading to additional nuclei) in Cu foils directly correlates with the extent of adlayer growth. Annealing in hydrogen gas atmosphere depletes the subsurface carbon in the Cu foil. Adlayer-free single crystal and polycrystalline single layer graphene films are grown on Cu(111) and polycrystalline Cu foils containing no subsurface carbon, respectively. This single crystal graphene contains parallel, centimeter-long ≈100 nm wide "folds," separated by 20 to 50 µm, while folds (and wrinkles) are distributed quasi-randomly in the polycrystalline graphene film. High-performance field-effect transistors are readily fabricated in the large regions between adjacent parallel folds in the adlayer-free single crystal graphene film.

13.
J Psychopharmacol ; 33(10): 1288-1302, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31294644

RESUMO

BACKGROUND: Compelling animal and clinical studies support the N-methyl-D-aspartate receptor (NMDAR) hypofunction hypothesis of schizophrenia and suggest promising pharmacological agents to ameliorate negative and cognitive symptoms of schizophrenia, including sarcosine, a glycine transporter-1 inhibitor. AIMS AND METHODS: It is imperative to evaluate the therapeutic potential of sarcosine in animal models, which provide indispensable tools for testing drug effects in detail and elucidating the underlying mechanisms. In this study, a series of seven experiments was conducted to investigate the effect of sarcosine in ameliorating behavioral deficits and the underlying mechanism in pharmacological (i.e., MK-801-induced) and genetic (i.e., serine racemase-null mutant (SR-/-) mice) NMDAR hypofunction models. RESULTS: In Experiment 1, the acute administration of 500/1000 mg/kg sarcosine (i.p.) had no adverse effects on motor function and serum biochemical responses. In Experiments 2-4, sarcosine significantly alleviated MK-801-induced (0.2 mg/kg) brain abnormalities and behavioral deficits in MK-801-induced and SR-/- mouse models. In Experiment 5, the injection of sarcosine enhanced CSF levels of glycine and serine in rat brain. In Experiments 6-7, we show for the first time that sarcosine facilitated NMDAR-mediated hippocampal field excitatory postsynaptic potentials and influenced the movement of surface NMDARs at extrasynaptic sites. CONCLUSIONS: Sarcosine effectively regulated the surface trafficking of NMDARs, NMDAR-evoked electrophysiological activity, brain glycine levels and MK-801-induced abnormalities in the brain, which contributed to the amelioration of behavioral deficits in mouse models of NMDAR hypofunction.


Assuntos
Sintomas Comportamentais/tratamento farmacológico , Encefalopatias/tratamento farmacológico , Proteínas da Membrana Plasmática de Transporte de Glicina/agonistas , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Sarcosina/farmacologia , Esquizofrenia/tratamento farmacológico , Animais , Sintomas Comportamentais/induzido quimicamente , Encefalopatias/induzido quimicamente , Modelos Animais de Doenças , Maleato de Dizocilpina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Racemases e Epimerases/genética , Sarcosina/administração & dosagem , Esquizofrenia/metabolismo , Esquizofrenia/patologia , Esquizofrenia/fisiopatologia
14.
J Endocrinol ; 242(1): M17-M32, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31141788

RESUMO

Prenatal caffeine exposure (PCE) can induce testicular developmental toxicity. Here, we aimed to explore the underlying mechanism of this process in reference to its intrauterine origin. Pregnant rats were intragastrically administrated caffeine (30 and 120 mg/kg/day) from gestational days 9 to 20. The results showed that the male fetuses exposed to high dose of caffeine (120 mg/kg/day) had a decreased bodyweight and inhibited testosterone synthetic function. Meanwhile, their serum corticosterone concentration was elevated and their testicular insulin-like growth factor 1 (Igf1) expression was decreased. Moreover, the histone 3 lysine 14 acetylation (H3K14ac) level in the Igf1 promoter region was reduced. Low-dose (30 mg/kg/day) caffeine exposure, however, increased steroidogenic enzymes expression in male fetuses. After birth, the serum corticosterone concentration gradually decreased in the PCE (120 mg/kg/day) offspring rats, whereas the expression and H3K14ac level of Igf1 gradually increased, with obvious catch-up growth and testicular development compensation. Intriguingly, when we subjected the offspring to 2 weeks of chronic stress to elevate the serum corticosterone concentration, the expression of Igf1 and testosterone synthesis were inhibited again in the PCE (120 mg/kg/day) group, accompanied by a decrease in the H3K14ac level in the Igf1 promoter region. In vitro, corticosterone (rather than caffeine) was proved to inhibit testosterone production in Leydig cells by altering the H3K14ac level and the expression of Igf1. These observations suggested that PCE-induced testicular developmental toxicity is related to the negative regulation of corticosterone on H3K14ac levels and the expression of Igf1.


Assuntos
Cafeína/toxicidade , Glucocorticoides/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Testículo/metabolismo , Testículo/patologia , Animais , Feminino , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Wistar , Testículo/efeitos dos fármacos , Testosterona/metabolismo
15.
PLoS One ; 14(3): e0208971, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30830910

RESUMO

Photosynthetic-nitrogen use efficiency (PNUE) is a useful trait to characterize leaf physiology and survival strategy. PNUE can also be considered as part of 'leaf economics spectrum' interrelated with leaf nutrient concentrations, photosynthesis and respiration, leaf life-span and dry-mass investment. However, few studies have paid attention to PNUE of N-fixing tree seedlings in subtropical China. In this study, we investigated the differences in PNUE, leaf nitrogen (N) allocation, and mesophyll conductance (gm) in Dalbergia odorifera and Erythrophleum fordii (N-fixing trees), and Betula alnoides and Castanopsis hystrix (non-N-fixing trees). PNUE of D. odorifera and E. fordii were significantly lower than those of B. alnoides and C. hystrix mainly because of their allocation of a lower fraction of leaf N to Rubisco (PR) and bioenergetics (PB). Mesophyll conductance had a significant positive correlation with PNUE in D. odorifera, E. fordii, and B. alnoides, but the effect of gm on PNUE was different between species. The fraction of leaf N to cell wall (PCW) had a significant negative correlation with PR in B. alnoides and C. hystrix seedling leaves, but no correlation in D. odorifera and E. fordii seedling leaves, which may indicate that B. alnoides and C. hystrix seedling leaves did not have enough N to satisfy the demand from both the cell wall and Rubisco. Our results indicate that B. alnoides and C. hystrix may have a higher competitive ability in natural ecosystems with fertile soil, and D. odorifera and E. fordii may grow well in N-poor soil. Mixing these non-N-fixing and N-fixing trees for afforestation is useful for improving soil N utilization efficiency in the tropical forests.


Assuntos
Nitrogênio/metabolismo , Árvores/fisiologia , China , Fotossíntese , Folhas de Planta/fisiologia , Plântula
16.
Hortic Res ; 6: 23, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30729013

RESUMO

Many studies suggest that there are distinct regulatory processes controlling compound leaf development in different clades of legumes. Loss of function of the LEAFY (LFY) orthologs results in a reduction of leaf complexity to different degrees in inverted repeat-lacking clade (IRLC) and non-IRLC species. To further understand the role of LFY orthologs and the molecular mechanism in compound leaf development in non-IRLC plants, we studied leaf development in unifoliate leaf (un) mutant, a classical mutant of mungbean (Vigna radiata L.), which showed a complete conversion of compound leaves into simple leaves. Our analysis revealed that UN encoded the mungbean LFY ortholog (VrLFY) and played a significant role in leaf development. In situ RNA hybridization results showed that STM-like KNOXI genes were expressed in compound leaf primordia in mungbean. Furthermore, increased leaflet number in heptafoliate leaflets1 (hel1) mutants was demonstrated to depend on the function of VrLFY and KNOXI genes in mungbean. Our results suggested that HEL1 is a key factor coordinating distinct processes in the control of compound leaf development in mungbean and its related non-IRLC legumes.

17.
Small ; 15(10): e1804806, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30721571

RESUMO

Anodes involving conversion and alloying reaction mechanisms are attractive for potassium-ion batteries (PIBs) due to their high theoretical capacities. However, serious volume change and metal aggregation upon potassiation/depotassiation usually cause poor electrochemical performance. Herein, few-layered SnS2 nanosheets supported on reduced graphene oxide (SnS2 @rGO) are fabricated and investigated as anode material for PIBs, showing high specific capacity (448 mAh g-1 at 0.05 A g-1 ), high rate capability (247 mAh g-1 at 1 A g-1 ), and improved cycle performance (73% capacity retention after 300 cycles). In this composite electrode, SnS2 nanosheets undergo sequential conversion (SnS2 to Sn) and alloying (Sn to K4 Sn23 , KSn) reactions during potassiation/depotassiation, giving rise to a high specific capacity. Meanwhile, the hybrid ultrathin nanosheets enable fast K storage kinetics and excellent structure integrity because of fast electron/ionic transportation, surface capacitive-dominated charge storage mechanism, and effective accommodation for volume variation. This work demonstrates that K storage performance of alloy and conversion-based anodes can be remarkably promoted by subtle structure engineering.

18.
Patient Prefer Adherence ; 13: 2159-2169, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31908423

RESUMO

Objectives: To investigate the initiation and persistence of antiplatelet agents and the associated factors for patients with acute coronary syndromes (ACS) in Tianjin, China. Methods: Data were obtained from Tianjin Urban Employee Basic Medical Insurance database (2011-2015). Adult patients who were discharged alive after the first ACS-related hospitalization (index hospitalization) between January 2012 and December 2014 were included. Patients who initiated with antiplatelet therapy, including aspirin monotherapy, clopidogrel monotherapy, or dual antiplatelet with aspirin and clopidogrel at discharge or within the initial 30-day follow-up after discharge were further identified. Patients with no gaps of ≥30 days in antiplatelet therapy were deemed persistent. The logistic model and Cox model were used to explore the associated factors of initiation and persistence with antiplatelet agents, respectively. Results: In total, 21,450 patients (64.6±10.7 years; 46.0% female) were included. Only 70.3% (N=15,071) of them initiated with antiplatelet agents within the initial 30-day follow-up; 85.0% (N=12,809) of the initial users discontinued their antiplatelet therapy, and the average time to discontinuation was 117.4±119.7 days. The patients who had prior antiplatelet agents utilization (Odds ratio [95% CI]=1.93 [1.78-2.09]; hazard ratio [95% CI]=0.78 [0.74-0.81]), received percutaneous coronary intervention (PCI) during the baseline period (OR=1.47 [1.26-1.73]; HR=0.91 [0.84-0.97]) or index hospitalization (OR=22.40 [18.63-26.92]; HR=0.51 [0.49-0.53]) were more likely to initiate and persist with antiplatelet agents, while the female (OR=0.75 [0.70-0.81]; HR=1.22 [1.88-1.27]) patients were less likely to initiate and persist with antiplatelet agents. Conclusion: The initiation and persistence with antiplatelet agents are poor among the ACS patients in Tianjin. Females are associated with poorer initiation and persistence, while prior antiplatelet agents use and receiving PCI during baseline period or index hospitalization are associated with better initial use and better persistence.

19.
Planta ; 249(3): 765-774, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30390139

RESUMO

MAIN CONCLUSION: The results provide a significant verification of functional redundancy and diversity of CUC/NAM genes in legumes. The CUP-SHAPED COTYLEDON/NO APICAL MERISTEM (CUC/NAM) orthologs play key roles for plant organ boundary formation and organ development. Here, we performed a forward screen of the gamma irradiation mutagenesis population in mungbean and characterised a mutant, reduced rachis and fused leaflets (rrf1), which gave rise to the formation of compound leaves with reduced rachis and fused leaflets. Map-based cloning revealed that RRF1 encoded a CUC/NAM protein in mungbean. Phylogenetic analysis indicated that legume CUC1/CUC2 genes were classified as belonging to two subclades, and there are different copies of CUC1/CUC2 genes in legumes. Transcriptomic analysis showed that expression levels of a set of developmental regulators, including class I KNOTTED-LIKE HOMEOBOXI (KNOXI) gene and LATERAL ORGAN BOUNDARIES DOMAIN (LBD) gene, were altered in rrf1 mutants compared to the wild-type plants. Furthermore, rrf1 genetically interacted with heptafoliate leaflets1 (hel1), a mutant displaying a seven-leaflet compound leaf, to regulate leaf development in mungbean. Our results suggest functional redundancy and diversity of two subclades of CUC1/CUC2 genes in legumes, following the duplication of an ancestral gene.


Assuntos
Genes de Plantas/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/fisiologia , Vigna/crescimento & desenvolvimento , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Filogenia , Folhas de Planta/genética , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vigna/genética
20.
J Integr Plant Biol ; 61(4): 463-477, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30129698

RESUMO

Legumes can control the number of symbiotic nodules that form on their roots, thus balancing nitrogen assimilation and energy consumption. Two major pathways participate in nodulation: the Nod factor (NF) signaling pathway which involves recognition of rhizobial bacteria by root cells and promotion of nodulation, and the autoregulation of nodulation (AON) pathway which involves long-distance negative feedback between roots and shoots. Although a handful of genes have a clear role in the maintenance of nodule number, additional unknown factors may also be involved in this process. Here, we identify a novel function for a Lotus japonicus ALOG (Arabidopsis LSH1 and Oryza G1) family member, LjALOG1, involved in positively regulating nodulation. LjALOG1 expression increased substantially after inoculation with rhizobia, with high levels of expression in whole nodule primordia and in the base of developing nodules. The ljalog1 mutants, which have an insertion of the LORE1 retroelement in LjALOG1, had significantly fewer nodules compared with wild type, along with increased expression of LjCLE-RS1 (L. japonicus CLE Root Signal 1), which encodes a nodulation suppressor in the AON pathway. In summary, our findings identified a novel factor that participates in controlling nodulation, possibly by suppressing the AON pathway.


Assuntos
Lotus/genética , Família Multigênica , Nodulação/genética , Regulação da Expressão Gênica de Plantas , Lotus/microbiologia , Mutagênese Insercional/genética , Mutação/genética , Filogenia , Plantas Geneticamente Modificadas , Rhizobium/fisiologia , Nódulos Radiculares de Plantas/genética , Nódulos Radiculares de Plantas/microbiologia , Análise de Sequência de DNA
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