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1.
New Phytol ; 242(3): 975-987, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38439696

RESUMEN

Stable oxygen isotope ratio of tree-ring α-cellulose (δ18Ocel) yields valuable information on many aspects of tree-climate interactions. However, our current understanding of the mechanistic controls on δ18Ocel is incomplete, with a knowledge gap existent regarding the fractionation effect characterizing carbonyl-water oxygen exchange during sucrose translocation from leaf to phloem. To address this insufficiency, we set up an experimental system integrating a vapor 18O-labeling feature to manipulate leaf-level isotopic signatures in tree saplings enclosed within whole-canopy gas-exchange cuvettes. We applied this experimental system to three different tree species to determine their respective relationships between 18O enrichment of sucrose in leaf lamina (Δ18Ol_suc) and petiole phloem (Δ18Ophl_suc) under environmentally/physiologically stable conditions. Based on the determined Δ18Ophl_suc-Δ18Ol_suc relationships, we estimated that on average, at least 25% of the oxygen atoms in sucrose undergo isotopic exchange with water along the leaf-to-phloem translocation path and that the biochemical fractionation factor accounting for such exchange is c. 34‰, markedly higher than the conventionally assumed value of 27‰. Our study represents a significant step toward quantitative elucidation of the oxygen isotope dynamics during sucrose translocation in trees. This has important implications with respect to improving the δ18Ocel model and its related applications in paleoclimatic and ecophysiological contexts.


Asunto(s)
Oxígeno , Árboles , Oxígeno/análisis , Sacarosa , Agua/análisis , Floema , Isótopos de Oxígeno/análisis , Hojas de la Planta/química , Isótopos de Carbono/análisis
2.
Angew Chem Int Ed Engl ; 63(36): e202408861, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-38898541

RESUMEN

Despite various efforts to optimize the near-infrared (NIR) performance of perylene diimide (PDI) derivatives for bio-imaging, convenient and efficient strategies to amplify the fluorescence of PDI derivatives in biological environment and the intrinsic mechanism studies are still lacking. Herein, we propose an alkyl-doping strategy to amplify the fluorescence of PDI derivative-based nanoparticles for improved NIR fluorescence imaging. The developed PDI derivative, OPE-PDI, shows much brighter in n-Hexane (HE) compared with that in other organic media, and the excited state dynamics investigation experimentally elucidates the solvent effect-induced suppression of intermolecular energy transfer and intramolecular nonradiative decay as the underlying mechanism for the fluorescence improvement. Theoretical calculations reveal the lowest reorganization energies of OPE-PDI in HE among various solvents, indicating the effectively suppressed conformational relaxation to support the strongest radiative decay. Inspired by this, an alkyl atmosphere mimicking HE is constructed by incorporating the octadecane into OPE-PDI-based nanoparticles, permitting up to 3-fold fluorescence improvement compared with the counterpart nanoparticles. Owing to the merits of high brightness, anti-photobleaching, and low biotoxicity for the optimal nanoparticles, they have been employed for probing and long-term monitoring of tumor. This work highlights a facile strategy for the fluorescence enhancement of PDI derivative-based nanoparticles.

3.
BMC Plant Biol ; 23(1): 442, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37726651

RESUMEN

BACKGROUND: Lodging is a major factor contributing to yield loss and constraining the mechanical harvesting of wheat crops. Genetic improvement through breeding effectively reduced the lodging and improved the grain yield, however, the physiological mechanisms involved in providing resistance to lodging are different in the breeding stage and are not clearly understood. The purpose of this study was to compare the differences in the lodging resistance (LR) of the wheat varieties released during the different decades and to explore the effect of the application of nitrogen (N) fertilizer on the plasticity of LR. RESULTS: A field study was conducted during the cultivation seasons of 2019-2020 and 2020-2021, in soil supplemented with three N levels: N0 (0 kg ha-1), N180 (200 kg ha-1), and N360 (360 kg ha-1) using eight varieties of wheat released for commercial cultivation from 1950 to date. The results obtained showed that genetic improvement had significantly enhanced the LR and grain yield in wheat. In the first breeding stage (from 1950 to 1980s) the lodging resistant index increased by 15.0%, which was primarily attributed to a reduced plant height and increased contents of cellulose, Si, and Zn. In the second breeding stage (the 1990s-2020s) it increased by 172.8%, which was mainly attributed to an increase in the stem diameter, wall thickness, and the contents of K, Ca, Fe, Mn, and Cu. The application of N fertilizer improved the grain yield but reduced the LR in wheat. This was mainly due to an increase in plant height resulting in an elevation of the plant center of gravity, a decrease in the contents of cellulose, and a reduction in the area of large-sized vascular bundles in the stems, even if N supplementation increased the concentrations of K, Ca, and Si. CONCLUSION: Although breeding strategies improved the stem strength, the trade-off between the grain yield and LR was more significantly influenced by the addition of N. Overcoming this peculiar situation will serve as a breakthrough in improving the seed yield in wheat crops in the future.


Asunto(s)
Fertilizantes , Triticum , Triticum/genética , Estaciones del Año , Fitomejoramiento , China , Celulosa , Productos Agrícolas , Grano Comestible
4.
Angew Chem Int Ed Engl ; 62(6): e202215372, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36480198

RESUMEN

Developing conjugated small molecules (CSM) with intense NIR-II (1000-1700 nm) absorption for phototheranostic is highly desirable but remains a tremendous challenge due to a lack of reliable design guidelines. This study reports a high-performance NIR-II CSM for phototheranostic by tailoring molecular planarity. A series of CSM show bathochromic absorption extended to the NIR-II region upon the increasing thiophene number, but an excessive number of thiophene results in decreased NIR-IIa (1300-1400 nm) brightness and photothermal effects. Further introduction of terminal nonconjugated alkyl chain can enhance NIR-II absorption coefficient, NIR-IIa brightness, and photothermal effects. Mechanism studies ascribe this overall enhancement to molecular planarity stemming from the collective contribution of donor/side-chain engineering. This finding directs the design of NIR-II CSM by rational manipulating molecular planarity to perform 1064 nm mediated phototheranostic at high efficiency.

5.
Plant Cell Environ ; 42(7): 2231-2244, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30938459

RESUMEN

Typical symptoms of potassium deficiency, characterized as chlorosis or withered necrosis, occur concomitantly with downregulated photosynthesis and impaired leaf water transport. However, the prominent limitations and mechanisms underlying the concerted decreases of leaf photosynthesis and hydraulic conductance are poorly understood. Monocots and dicots were investigated based on responses of photosynthesis and hydraulic conductance and their components and the correlated anatomical determinants to potassium deficiency. We found a conserved pattern in which leaf photosynthesis and hydraulic conductance concurrently decreased under potassium starvation. However, monocots and dicots showed two different hydraulic-redesign strategies: Dicots tended to show a decreased minor vein density, whereas monocots reduced the size of the bundle sheath and its extensions, rather than the minor vein density; both of these strategies may restrain xylem and outside-xylem hydraulic conductance. Additionally, potassium-deprived leaves developed with fewer mesophyll cell-to-cell connections, leading to a reduced area being available for liquid-phase flow. Further quantitative analysis revealed that mesophyll conductance to CO2 and outside-xylem hydraulic resistance were the major contributors to photosynthetic limitation and increased hydraulic resistance, at more than 50% and 60%, respectively. These results emphasize the importance of potassium in the coordinated regulation of leaf photosynthesis and hydraulic conductance through modifications of leaf anatomy.


Asunto(s)
Fotosíntesis/fisiología , Hojas de la Planta/anatomía & histología , Hojas de la Planta/fisiología , Potasio/metabolismo , Transporte Biológico , Brassica napus , Dióxido de Carbono , Cucumis sativus , Magnoliopsida/anatomía & histología , Magnoliopsida/fisiología , Células del Mesófilo/fisiología , Estomas de Plantas/fisiología , Transpiración de Plantas , Triticum , Agua/fisiología , Xilema/fisiología
6.
Physiol Plant ; 167(3): 352-364, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30536828

RESUMEN

Sheath rot disease (ShR) caused by Sarocladium oryzae (S. oryzae) infection is an emerging disease that causes severe yield loss by restricting the translocation of non-structural carbohydrates (NSC). Potassium (K) nutrition plays a critical role in disease resistance and the exportation of NSC. However, the physiological mechanisms of K with respect to ShR have not been thoroughly elucidated to date. The objectives of this study were to reveal the mechanisms by which K increases ShR resistance by regulating NSC translocation of rice, therefore, a field experiment combined with an inoculation experiment was conducted. We demonstrate that ShR disease incidence and disease index decreased dramatically with an increasing K application. K deficiency sharply induced the accumulation of NSC in the flag leaf (FL) and flag leaf sheath (FLS) under S. oryzae infection condition, which reduced the contribution of transferred NSC to final yield. A permutational multivariate analysis showed that K deficiency had a greater (49.0%, P < 0.001) effect on the NSC content variation in FL than that of S. oryzae infection (15.0%, P < 0.001). S. oryzae infection dramatically increased the difference in apparent transferred mass of NSC and cell membrane injury of diseased organs between K-deficient and K-sufficient rice. Finally, we demonstrate that cell membrane injury was a limiting factor imposed by K deficiency, which restricts the export of NSC from source organs. This work highlights the importance of K in improving ShR resistance by regulating NSC translocation (particularly the stem NSC).


Asunto(s)
Oryza/metabolismo , Resistencia a la Enfermedad/genética , Resistencia a la Enfermedad/fisiología , Oryza/genética , Enfermedades de las Plantas/genética , Potasio/metabolismo , Deficiencia de Potasio
7.
Cell Physiol Biochem ; 50(4): 1601-1616, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30359966

RESUMEN

BACKGROUNDS/AIMS: It has been reported that myocardial infarction (MI) is a risk factor for vascular dementia. However, the molecular mechanism remains largely unknown. METHODS: MI mice were generated by ligation of the left coronary artery (LCA) for 4 weeks. Passive and active avoidance tests were performed to evaluate the cognitive ability of MI mice. A theta-burst stimulation (TBS) protocol was applied to elicit long-term potentiation (LTP) of the perforant pathway-dentate gyrus synapse (PP-DG). Western blot analysis was employed to assess protein levels. RESULTS: In this study, we demonstrated that after 4 weeks of MI, C57BL/6 mice had significantly impaired memory. Compared with the sham group, in vivo physiological recording in the MI group revealed significantly decreased amplitude of population spikes (PS) with no effect on the latency and duration of the stimulus-response curve. The amplitude of LTP was markedly decreased in the MI group compared with the sham group. Further examination showed that the expression of the TBS-LTP-related proteins BDNF, GluA1 and phosphorylated GluA1 were all decreased in the MI group compared with those in the sham group. Strikingly, all these changes were prevented by hippocampal stereotaxic injection of an anti-miR-1 oligonucleotide fragment carried by a lentivirus vector (lenti-pre-AMO-1). CONCLUSION: MI induced cognitive decline and TBS-LTP impairment, and decreased BDNF and GluA1 phosphorylation levels from overexpression of miR-1ated were involved in this process.


Asunto(s)
Potenciación a Largo Plazo/fisiología , MicroARNs/metabolismo , Infarto del Miocardio/patología , Animales , Antagomirs/metabolismo , Conducta Animal , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Células Cultivadas , Giro Dentado/fisiología , Modelos Animales de Enfermedad , Estimulación Eléctrica , Electrodos Implantados , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Infarto del Miocardio/metabolismo , Neuronas/citología , Neuronas/metabolismo , Mapas de Interacción de Proteínas , Receptores AMPA/metabolismo , Sinapsis/metabolismo
8.
BMC Plant Biol ; 17(1): 240, 2017 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-29228924

RESUMEN

BACKGROUND: Most studies of photosynthesis in chlorenchymas under potassium (K) deficiency focus exclusively on leaves; however, little information is available on the physiological role of K on reproductive structures, which play a critical role in plant carbon gain. Brassica napus L., a natural organ-succession species, was used to compare the morphological, anatomical and photo-physiological differences between leaves and siliques exposed to K-deficiency. RESULTS: Compared to leaves, siliques displayed considerably lower CO2 assimilation rates (A) under K-deficient (-K) or sufficient conditions (+K), limited by decreased stomatal conductance (g s), apparent quantum yield (α) and carboxylation efficiency (CE), as well as the ratio of the maximum rate of electron transport (J max) and the maximum rate of ribulose 1,5-bisphosphate (RuBP) carboxylation (V cmax). The estimated J max, V cmax and α of siliques were considerably lower than the theoretical value calculated on the basis of a similar ratio between these parameters and chlorophyll concentration (i.e. J max/Chl, V cmax/Chl and α/Chl) to leaves, of which the gaps between estimated- and theoretical-J max was the largest. In addition, the average ratio of J max to V cmax was 16.1% lower than that of leaves, indicating that the weakened electron transport was insufficient to meet the requirements for carbon assimilation. Siliques contained larger but fewer stoma, tightly packed cross-section with larger cells and fewer intercellular air spaces, fewer and smaller chloroplasts and thin grana lamellae, which might be linked to the reduction in light capture and CO2 diffusion. K-deficiency significantly decreased leaf and silique A under the combination of down-regulated stomatal size and g s, chloroplast number, α, V cmax and J max, while the CO2 diffusion distance between chloroplast and cell wall (D chl-cw) was enhanced. Siliques were more sensitive than leaves to K-starvation, exhibiting smaller reductions in tissue K and parameters such as g s, V cmax, J max and D chl-cw. CONCLUSION: Siliques had substantially smaller A than leaves, which was attributed to less efficient functioning of the photosynthetic apparatus, especially the integrated limitations of biochemical processes (J max and V cmax) and α; however, siliques were slightly less sensitive to K deficiency.


Asunto(s)
Brassica napus/anatomía & histología , Brassica napus/metabolismo , Fotosíntesis , Potasio/metabolismo , Carbono/metabolismo , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Hojas de la Planta/anatomía & histología , Hojas de la Planta/metabolismo , Semillas/anatomía & histología , Semillas/metabolismo
9.
Plant Cell Environ ; 39(11): 2428-2439, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27423139

RESUMEN

Leaves exposed to potassium (K) deficiency usually present decreased mesophyll conductance (gm ) and photosynthesis (A). The relative contributions of leaf anatomical traits in determining gm have been quantified; however, anatomical variabilities related to low gm under K starvation remain imperfectly known. A one-dimensional model was used to quantify anatomical controls of the entire CO2 diffusion pathway resistance within a leaf on two Brassica napus L. cultivars in response to K deficiency. Leaf photosynthesis of both cultivars was significantly decreased under K deficiency in parallel with down-regulated gm . The mesophyll conductance limitation contributed to more than one-half of A decline. The decreased internal air space in K-starved leaves was associated with the increase of gas-phase resistance. Potassium deficiency reduced liquid-phase conductance by decreasing the exposed surface area of chloroplasts per unit leaf area (Sc /S), and enlarging the resistance of the cytoplasm that can be interpreted by the increasing distance of chloroplast from cell wall, and between adjacent chloroplasts. Additionally, the discrepancies of A between two cultivars were in part because of gm variations, ascribing to an altered Sc /S. These results emphasize the important role of K on the regulation of gm by enhancing Sc /S and reducing cytoplasm resistance.


Asunto(s)
Brassica napus/metabolismo , Fotosíntesis , Potasio/metabolismo , Brassica napus/anatomía & histología , Brassica napus/fisiología , Dióxido de Carbono/metabolismo , Células del Mesófilo/metabolismo , Células del Mesófilo/fisiología , Hojas de la Planta/anatomía & histología , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología
10.
Hortic Res ; 11(6): uhae112, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38919556

RESUMEN

Plants primarily incorporate nitrate (NO3 -) and ammonium (NH4 +) as the primary source of inorganic nitrogen (N); the physiological mechanisms of photosynthesis (A) dropdown under NH4 + nutrition has been investigated in many studies. Leaf anatomy is a major determinant to mesophyll conductance (g m) and photosynthesis; however, it remains unclear whether the photosynthesis variations of plants exposed to different N forms is related to leaf anatomical variation. In this work, a common shrub, Lonicera japonica was hydroponically grown under NH4 +, NO3 - and 50% NH4 +/NO3 -. We found that leaf N significantly accumulated under NH4 +, whereas the photosynthesis was significantly decreased, which was mainly caused by a reduced g m. The reduced g m under NH4 + was related to the decreased intercellular air space, the reduced chloroplast number and especially the thicker cell walls. Among the cell wall components, lignin and hemicellulose contents under NH4 + nutrition were significantly higher than those in the other two N forms and were scaled negatively correlated with g m; while pectin content was independent from N forms. Pathway analysis further revealed that the cell wall components might indirectly regulate g m by influencing the thickness of the cell wall. These results highlight the importance of leaf anatomical variation characterized by modifications of chloroplasts number and cell wall thickness and compositions, in the regulation of photosynthesis in response to varied N sources.

11.
Chem Sci ; 15(30): 12086-12097, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39092116

RESUMEN

Hypoxia featured in malignant tumors and the short lifespan of photo-induced reactive oxygen species (ROS) are two major issues that limit the efficiency of photodynamic therapy (PDT) in oncotherapy. Developing efficient type-I photosensitizers with long-term ˙OH generation ability provides a possible solution. Herein, a semiconducting polymer-based photosensitizer PCPDTBT was found to generate 1O2, ˙OH, and H2O2 through type-I/II PDT paths. After encapsulation within a mesoporous silica matrix, the NIR-II fluorescence and ROS generation are enhanced by 3-4 times compared with the traditional phase transfer method, which can be attributed to the excited-state lifetime being prolonged by one order of magnitude, resulting from restricted nonradiative decay channels, as confirmed by femtosecond spectroscopy. Notably, H2O2 production reaches 15.8 µM min-1 under a 730 nm laser (80 mW cm-2). Further adsorption of Fe2+ ions on mesoporous silica not only improves the loading capacity of the chemotherapy drug doxorubicin but also triggers a Fenton reaction with photo-generated H2O2 in situ to produce ˙OH continuously after the termination of laser irradiation. Thus, semiconducting polymer-based nanocomposites enables NIR-II fluorescence imaging guided persistent PDT under hypoxic conditions. This work provides a promising paradigm to fabricate persistent photodynamic therapy platforms for hypoxia-tolerant phototheranostics.

12.
Mol Genet Genomic Med ; 12(8): e2503, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39140707

RESUMEN

BACKGROUND: The causes of migraine remain unclear. Evidence suggests that the MAPK and PI3K/Akt signaling pathways play a role in migraine pathogenesis. However, studies on genetic polymorphisms in the two pathways associated with migraine are still limited. METHODS: This study included 226 migraineurs and 452 age- and sex-matched nonmigraine control individuals. Genotyping of 31 Single Nucleotide Polymorphisms (SNPs) in 21 genes was performed. The relationship between migraine and gene polymorphisms was analyzed by using logistic regression. SNP-SNP interactions were examined by a generalized multifactor dimension reduction (GMDR) approach. The possible role of SNPs was evaluated with gene expression data from the GTEx database. RESULTS: The RASGRP2-rs2230414 GT genotype was associated with decreased migraine risk compared with the wild-type GG genotype [ORadj (95% CI): 0.674(0.458-0.989)]. PIK3R1-rs3730089 was associated with migraine in the recessive model [ORadj (95% CI): 1.446(1.004-2.083)]. The CACNA1H-rs61734410 CT genotype was associated with migraine risk [ORadj (95% CI): 1.561(1.068-2.281)]. One significant two-way SNP-SNP interaction was found (PRKCA rs2228945-BDNF rs6265) (p = 0.0107). Significant eQTL and sQTL signals were observed for the SNP rs2230414. CONCLUSIONS: This is the first study to systematically reveal significant associations between MAPK and PI3K/Akt signaling pathway-related gene polymorphisms and migraine risk.


Asunto(s)
Trastornos Migrañosos , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas c-akt , Humanos , Trastornos Migrañosos/genética , Femenino , Masculino , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Adulto , Transducción de Señal/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Sistema de Señalización de MAP Quinasas/genética , Fosfatidilinositol 3-Quinasa Clase Ia/genética , Persona de Mediana Edad
13.
Korean J Pain ; 36(3): 335-346, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37394274

RESUMEN

Background: Perampanel, a highly selective glutamate AMPA receptor antagonist, is widely used to treat epilepsy. Since the existence of common pathophysiological features between epilepsy and migraine, the aim of this study was to investigate whether perampanel could exert an antimigraine effect. Methods: Nitroglycerin (NTG) was used to induce a migraine model in rats, and the model animals were pretreatment with 50 µg/kg and 100 µg/kg perampanel. The expression of pituitary adenylate-cyclase-activating polypeptide (PACAP) was quantified by western blot and quantitative real-time PCR in the trigeminal ganglion, and rat-specific enzyme-linked immunosorbent assay in serum. Western blot was also conducted to explore the effects of perampanel treatment on the phospholipase C (PLC)/protein kinase C (PKC) and protein kinase A (PKA)/cAMP-responsive-element-binding protein (CREB) signaling pathways. Moreover, the cAMP/PKA/CREB-dependent mechanism was evaluated via in vitro stimulation of hippocampal neurons. The cells were treated with perampanel, antagonists and agonists for 24 hours and cell lysates were prepared for western blot analysis. Results: Perampanel treatment notably increased the mechanical withdrawal threshold and decreased head grooming and light-aversive behaviors in NTG-treated rats. It also decreased PACAP expression and affected cAMP/PKA/CREB signaling pathway. However, PLC/PKC signaling pathway may not be involved in this treatment. In in vitro studies, perampanel notably decreased PACAP expression by inhibiting cAMP/PKA/CREB signaling pathway. Conclusions: This study shows that perampanel inhibits the migraine-like pain response and that this beneficial effect might be attributable to regulation of the cAMP/PKA/CREB signaling pathway.

14.
Front Plant Sci ; 14: 1110257, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36866365

RESUMEN

Enhancing photosynthetic capacity is widely accepted as critical to advancing crop yield. Therefore, identifying photosynthetic parameters positively related to biomass accumulation in elite cultivars is the major focus of current rice research. In this work, we assessed leaf photosynthetic performance, canopy photosynthesis, and yield attributes of super hybrid rice cultivars Y-liangyou 3218 (YLY3218) and Y-liangyou 5867 (YLY5867) at tillering stage and flowering stage, using inbred super rice cultivars Zhendao11(ZD11) and Nanjing 9108 (NJ9108) as control. A diurnal canopy photosynthesis model was applied to estimate the influence of key environmental factors, canopy attributes, and canopy nitrogen status on daily aboveground biomass increment (AMDAY). Results showed that primarily the light-saturated photosynthetic rate at tillering stage contributed to the advancing yield and biomass of super hybrid rice in comparison to inbred super rice, and the light-saturated photosynthetic rate between them was similar at flowering stage. At tillering stage, the higher CO2 diffusion capacity, together with higher biochemical capacity (i.e., maximum carboxylation rate of Rubisco, maximum electron transport rate (J max), and triose phosphate utilization rate) favored leaf photosynthesis of super hybrid rice. Similarly, AMDAY in super hybrid rice was higher than inbred super rice at tillering stage, and comparable at flowering stage partially due to increased canopy nitrogen concentration (SLNave) of inbred super rice. At tillering stage, model simulation revealed that replacement of J max and g m in inbred super rice by super hybrid rice always had a positive effect on AMDAY, and the averaged AMDAY increment was 5.7% and 3.4%, respectively. Simultaneously, the 20% enhancement of total canopy nitrogen concentration through the improvement of SLNave (TNC-SLNave) resulted in the highest AMDAY across cultivars, with an average increase of 11.2%. In conclusion, the advancing yield performance of YLY3218 and YLY5867 was due to the higher J max and g m at tillering stage, and TCN-SLNave is a promising target for future super rice breeding programs.

15.
Front Plant Sci ; 14: 1164866, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37123833

RESUMEN

Magnesium is an essential macronutrient for plant photosynthesis, and in response to Mg deficiency, dicots appear more sensitive than monocots. Under Mg deficiency, we investigated the causes of differing photosynthetic sensitivities in a dicot and a monocot species. Rice (Oryza sativa L.) and cucumber (Cucumis sativus L.) were grown in hydroponic culture to explore their physiological responses to Mg deficiency stress. Both Mg-deficient rice and cucumber plants exhibited lower biomass, leaf area, Mg concentration, and chlorophyll content (Chl) compared with Mg-sufficient plants. However, a more marked decline in Chl and carotenoid content (Car) occurred in cucumber. A lower CO2 concentration in chloroplasts (C c) was accompanied by a decrease in the maximum rate of electron transport (J max) and the maximum rate of ribulose 1,5-bisphosphate carboxylation (V cmax), restricting CO2 utilization in Mg-deficient plants. Rice and cucumber photorespiration rate (P r) increased under Mg deficiency. Additionally, for cucumber, Car and non-photochemical quenching (NPQ) were reduced under lower Mg supply. Meanwhile, cucumber Mg deficiency significantly increased the fraction of absorbed light energy dissipated by an additional quenching mechanism (Φf,D). Under Mg deficiency, suppressed photosynthesis was attributed to comprehensive restrictions of mesophyll conductance (g m), J max, and V cmax. Cucumber was more sensitive to Mg deficiency than rice due to lower NPQ, higher rates of electron transport to alternative pathways, and subsequently, photooxidation damage.

16.
Chem Asian J ; 18(12): e202300351, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37150749

RESUMEN

Developing photostable two-photon dyes with high brightness and negligible photocytotoxicity is of key importance in fluorescence imaging but remains a huge challenge. Here, a two-photon dye with ultrahigh brightness and photostability is demonstrated for high-performance long-term two-photon fluorescence imaging. By terminated donor engineering, the designed DBD shows a higher two-photon absorption cross-section (δ, 418 GM vs 329 GM) and photoluminescence quantum yield (ΦPL , 62.74% vs 54.63%) than its counterpart DBA. As a consequence, two-photon fluorescence brightness (δ×ΦPL ) of DBD exhibits a 10-folded enhancement (262 GM vs 19 GM) in comparison with typical Coumarin 307 dye. More importantly, DBD displays ultrahigh photostability and negligible photobleaching under 10 min femtosecond laser irradiation, which stands in marked contrast to Coumarin 307. Furthermore, femtosecond transient absorption spectroscopy ascribes this ultrahigh photostability and negligible photobleaching to the inefficient intersystem crossing. With these merits, DBD can be used long-term two-photon fluorescence imaging in vitro.


Asunto(s)
Colorantes Fluorescentes , Fotones , Colorantes Fluorescentes/química , Imagen Óptica
17.
Int J Stroke ; 18(3): 304-311, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35699502

RESUMEN

BACKGROUND: Adherence to evidence-based hospital stroke care is variable and may change over time. It is important to determine which process measures are associated with variation in outcome. In a large dataset, we analyzed the association between process and outcome and the fluctuations of indicators over time, and identified quality indicators (QIs) that should be prioritized for improving the quality of stroke care. METHODS: We analyzed data from 123,259 patients diagnosed with acute ischemic stroke (AIS) who were treated at 109 large tertiary hospitals in China between January 2011 and May 2017. In total, 12 stroke treatment indicators were selected to calculate the hospital process composite performance (HPCP). Hospitals were divided into subgroups according to the time trend of HPCP estimated by the Group-Based Model. We analyzed the influence of hospital subgroups on the patient outcomes using a multi-level model and explored the QIs that led to variation. RESULTS: The HPCP trends for stroke indicators of 109 hospitals over 7 years were divided into two groups (Group 1, low-HPCP; Group 2, high-HPCP). After adjusting for patient age, medical insurance, comorbidities, patterns of admission, and NIHSS-scores, patients in the high-HPCP group presented higher rate of independence and longer length of stay compared to the low-HPCP group. The multi-level model showed that there was a statistically significant difference in the utilization rate between the two groups, with most marked differences seen in emergency assessment and function evaluation indicators. CONCLUSION: Variation in the quality of stroke care exists across hospitals, and better adherence to guideline-based care is associated with improved outcomes. We found that QIs related to emergency examination and functional assessment were the main factors differing between good and poor adherers to stroke indicators, suggesting that quality improvement in stroke care could prioritize these QIs.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/diagnóstico , Indicadores de Calidad de la Atención de Salud , Comorbilidad , Centros de Atención Terciaria
18.
Front Hum Neurosci ; 17: 1082317, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36875229

RESUMEN

Migraine is a common disease of the nervous system that seriously affects the quality of life of patients and constitutes a growing global health crisis. However, many limitations and challenges exist in migraine research, including the unclear etiology and the lack of specific biomarkers for diagnosis and treatment. Electroencephalography (EEG) is a neurophysiological technique for measuring brain activity. With the updating of data processing and analysis methods in recent years, EEG offers the possibility to explore altered brain functional patterns and brain network characteristics of migraines in depth. In this paper, we provide an overview of the methodology that can be applied to EEG data processing and analysis and a narrative review of EEG-based migraine-related research. To better understand the neural changes of migraine or to provide a new idea for the clinical diagnosis and treatment of migraine in the future, we discussed the study of EEG and evoked potential in migraine, compared the relevant research methods, and put forwards suggestions for future migraine EEG studies.

19.
Front Genet ; 14: 1158028, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37303955

RESUMEN

Background: Genetic and environmental factors contribute to migraine and the comorbidities of anxiety and depression. However, the association between genetic polymorphisms in the transient receptor potential (TRP) channels and glutamatergic synapse genes with the risk of migraine and the comorbidities of anxiety and depression remain unclear. Methods: 251 migraine patients containing 49 comorbidities with anxiety and 112 with depression and 600 controls were recruited. A customized 48-plex SNPscan kit was used for genotyping 13 SNPs of nine target genes. Logistic regression was conducted to analyze these SNPs' association with the susceptibility of migraine and comorbidities. The generalized multifactor dimension reduction (GMDR) was applied to analyze the SNP-SNP and gene-environment interactions. The GTEx database was used to examine the effects of the significant SNPs on gene expressions. Results: The TRPV1 rs8065080 and TRPV3 rs7217270 were associated with an increased risk of migraine in the dominant model [ORadj (95% CI): 1.75 (1.09-2.90), p = 0.025; 1.63 (1.02-2.58), p = 0.039, respectively]. GRIK2 rs2227283 was associated with migraine in the edge of significance [ORadj (95% CI) = 1.36 (0.99-1.89), p = 0.062]. In migraine patients, TRPV1 rs222741 was associated with both anxiety risk and depression risk in the recessive model [ORadj (95% CI): 2.64 (1.24-5.73), p = 0.012; 1.97 (1.02-3.85), p = 0.046, respectively]. TRPM8 rs7577262 was associated with anxiety (ORadj = 0.27, 95% CI = 0.10-0.76, p = 0.011). TRPV4 rs3742037, TRPM8 rs17862920 and SLC17A8 rs11110359 were associated with depression in dominant model [ORadj (95% CI): 2.03 (1.06-3.96), p = 0.035; 0.48 (0.23-0.96), p = 0.042; 0.42 (0.20-0.84), p = 0.016, respectively]. Significant eQTL and sQTL signals were observed for SNP rs8065080. Individuals with GRS (Genetic risk scores) of Q4 (14-17) had a higher risk of migraine and a lower risk of comorbidity anxiety than those with Genetic risk scores scores of Q1 (0-9) groups [ORadj (95% CI): 2.31 (1.39-3.86), p = 0.001; 0.28 (0.08-0.88), p = 0.034, respectively]. Conclusion: This study suggests that TRPV1 rs8065080, TRPV3 rs7217270, and GRIK2 rs2227283 polymorphism may associate with migraine risk. TRPV1 rs222741 and TRPM8 rs7577262 may associate with migraine comorbidity anxiety risk. rs222741, rs3742037, rs17862920, and rs11110359 may associate with migraine comorbidity depression risk. Higher GRS scores may increase migraine risk and decrease comorbidity anxiety risk.

20.
Plant Physiol Biochem ; 178: 105-115, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35279007

RESUMEN

It is well documented that yield superiority of super hybrid rice is linked with its improved photosynthetic capacity and/or efficiency. In natural environments, the amounts of CO2 assimilated by plants was also impacted by the rapidity of leaf photosynthesis response to fluctuations of light. However, it remains unknow whether the high yield of super hybrid rice was associated with photosynthetic traits under dynamic state. Here, photosynthetic traits under steady-and dynamic state in two super hybrid rice varieties (Ylinagyou 3218 and Yliangyou 5867) with high yield and two inbred super rice varieties (Zhendao 11 and Nanjing 9108) with lower yield. Under steady state, the net photosynthetic rate (A*) in super hybrid rice was 25.3% larger compared with inbred super rice. During photosynthetic induction, there was no obvious association of the rapidity of net photosynthesis rate (A) to sunflecks with rice subpopulations. Stomatal conductance (gs) of super hybrid rice increased slower than that of inbred super rice. The cumulative CO2 fixation (CCF) during photosynthetic induction was 25.2% larger in super hybrid rice than that in inbred super rice. The primary limitation during induction was biochemical limitation rather than stomatal limitation. There was a significantly positive relationship between A* and CCF, while A* was not related with the induction response rate of A. Overall, A* and CCF in super hybrid rice have been improved together, which contributed to its yield superiority, whereas its yield potential still can be improved by increasing induction rate of A under fluctuations of irradiance.


Asunto(s)
Oryza , Ambiente , Oryza/genética , Fotosíntesis/fisiología , Hojas de la Planta/fisiología
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