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1.
Inorg Chem ; 63(19): 8832-8845, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38687621

RESUMEN

To efficiently degrade organic pollutants, photocatalysts must be effective under both ultraviolet (UV) radiation and sunlight. We synthesized a series of new metal-organic frameworks by using mild hydrothermal conditions. These frameworks incorporate three distinct bipyridyl ligands: pyrazine (pyr), 4,4'-bipyridine (bpy), and 1,2-bis(4-pyridyl)ethane (bpe). The resulting compounds are denoted as [Cu(pyz)(H2O)2MF6], [Cu(bpy)2(H2O)2]·MF6, and [Cu(bpe)2(H2O)2]·MF6·H2O [M = Zr (1, 3, and 5) and Hf (2, 4, and 6)]. All six compounds exhibited a two-dimensional crystal structure comprising infinitely nonintersecting linear chains. Compound 3 achieved 100% degradation of methylene blue (MB) after 8 min under UV irradiation and 100 min under natural sunlight in the presence of H2O2 as the electron acceptor. For compound 5, 100% MB degradation was achieved after 120 min under sunlight and 10 min under UV light. Moreover, reactive radical tests revealed that the dominant species involved in photocatalytic degradation are hydroxyl (•OH), superoxide radicals (•O2-), and photogenerated holes (h+). The photodegradation process followed pseudo-first-order kinetics, with photodegradation rate constants of 0.362 min-1 (0.039 min-1) for 3 and 0.316 min-1 (0.033 min-1) for 5 under UV (sunlight) irradiation. The developed photocatalysts with excellent activity and good recyclability are promising green catalysts for degrading organic pollutants during environmental decontamination.

2.
Small ; : e2311274, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38511575

RESUMEN

Preclinical drug screening for cardiac toxicity has traditionally relied on observing changes in cardiomyocytes' electrical activity, primarily through invasive patch clamp techniques or non-invasive microelectrode arrays (MEA). However, relying solely on field potential duration (FPD) measurements for electrophysiological assessment can miss the full spectrum of drug-induced toxicity, as different drugs affect cardiomyocytes through various mechanisms. A more comprehensive approach, combining field potential and contractility measurements, is essential for accurate toxicity profiling, particularly for drugs targeting contractile proteins without affecting electrophysiology. However, previously proposed platform has significant limitations in terms of simultaneous measurement. The novel platform addresses these issues, offering enhanced, non-invasive evaluation of drug-induced cardiotoxicity. It features eight cantilevers with patterned strain sensors and MEA, enabling real-time monitoring of both cardiomyocyte contraction force and field potential. This system can detect minimum cardiac contraction force of ≈2 µN and field potential signals with 50 µm MEA diameter, using the same cardiomyocytes in measurements of two parameters. Testing with six drugs of varied mechanisms of action, the platform successfully identifies these mechanisms and accurately assesses toxicity profiles, including drugs not inhibiting potassium channels. This innovative approach presents a comprehensive, non-invasive method for cardiac function assessment, poised to revolutionize preclinical cardiotoxicity screening.

3.
Analyst ; 149(1): 254, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38047466

RESUMEN

Correction for 'Quantitative assessment of cardiomyocyte mechanobiology through high-throughput cantilever-based functional well plate systems' by Jongyun Kim et al., Analyst, 2023, 148, 5133-5143, https://doi.org/10.1039/D3AN01286G.

4.
Lab Chip ; 24(1): 149, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38031913

RESUMEN

Correction for 'Enhanced cardiomyocyte structural and functional anisotropy through synergetic combination of topographical, conductive, and mechanical stimulation' by Jongyun Kim et al., Lab Chip, 2023, 23, 4540-4551, https://doi.org/10.1039/D3LC00451A.

5.
Analyst ; 148(20): 5133-5143, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37695027

RESUMEN

Proper regulation of the in vitro cell culture environment is essential for disease modelling and drug toxicity screening. The main limitation of well plates used for cell culture is that they cannot accurately maintain energy sources and compounds needed during cell growth. Herein, to understand the importance of perfusion in cardiomyocyte culture, changes in contractile force and heart rate during cardiomyocyte growth are systematically investigated, and the results are compared with those of a perfusion-free system. The proposed perfusion system consists of a Peltier refrigerator, a peristaltic pump, and a functional well plate. A functional well plate with 12 wells is made through injection moulding, with two tubes integrated in the cover for each well to continuously circulate the culture medium. The contractile force of cardiomyocytes growing on the cantilever surface is analysed through changes in cantilever displacement. The maturation of cardiomyocytes is evaluated through fluorescence staining and western blot; cardiomyocytes cultured in the perfusion system show greater maturity than those cultured in a manually replaced culture medium. The pH of the culture medium manually replaced at intervals of 3 days decreases to 6.8, resulting in an abnormal heartbeat, while cardiomyocytes cultured in the perfusion system maintained at pH 7.4 show improved contractility and a uniform heart rate. Two well-known ion channel blockers, verapamil and quinidine, are used to measure changes in the contractile force of cardiomyocytes from the two systems. Cardiomyocytes in the perfusion system show greater stability during drug toxicity screening, proving that the perfusion system provides a better environment for cell growth.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Miocitos Cardíacos , Humanos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/metabolismo , Técnicas de Cultivo de Célula , Verapamilo/farmacología , Evaluación Preclínica de Medicamentos , Células Cultivadas
6.
Lab Chip ; 23(20): 4540-4551, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37771289

RESUMEN

Drug-induced cardiotoxicity, a significant concern in the pharmaceutical industry, often results in the withdrawal of drugs from the market. The main cause of drug-induced cardiotoxicity is the use of immature cardiomyocytes during in vitro drug screening procedures. Over time, several methods such as topographical, conductive, and mechanical stimulation have been proposed to enhance both maturation and contractile properties of these cardiomyocytes. However, the synergistic effects of integrating topographical, conductive, and mechanical stimulation for cardiomyocyte maturation remain underexplored and poorly understood. To address this limitation, herein, we propose a grooved polydimethylsiloxane (PDMS) membrane embedded with silver nanowires (AgNWs-E-PDMS). The proposed AgNWs-E-PDMS membrane enhances the maturation of cardiomyocytes and provides a more accurate evaluation of drug-induced cardiotoxicity. When subjected to 10% tensile stress on the AgNWs-E-PDMS membrane, cardiomyocytes displayed substantial enhancements. Specifically, the contraction force, sarcomere length, and connexin-43 (Cx43) expression are increased by 2.0-, 1.5-, and 2.4-times, respectively, compared to the control state. The practical feasibility of the proposed device as a drug screening platform is demonstrated by assessing the adverse effects of lidocaine on cardiomyocytes. The contraction force and beat rate of lidocaine treated cardiomyocytes cultured on the AgNWs-E-PDMS membrane under mechanical stimulation decreased to 0.9 and 0.64 times their initial values respectively, compared to 0.6 and 0.51 times in the control state. These less pronounced changes in the contraction force and beat rate signify the superior drug response in the cardiomyocytes, a result of their enhanced maturation and growth on the AgNWs-E-PDMS membrane combined with mechanical stimulation.


Asunto(s)
Miocitos Cardíacos , Nanocables , Humanos , Miocitos Cardíacos/fisiología , Cardiotoxicidad/metabolismo , Anisotropía , Plata/farmacología , Lidocaína/metabolismo , Lidocaína/farmacología
7.
Water Res ; 222: 118864, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35870393

RESUMEN

Environmental damage from serious nuclear accidents should be urgently restored, which needs the removal of radioactive species. Radioactive iodine isotopes are particularly problematic for human health because they are released in large amounts and retain radioactivity for a substantial time. Herein, we prepare platinum-coated iron nanoparticles (Fe@Pt) as a highly selective and reusable adsorbent for iodine species, i.e., iodide (I-), iodine (I2), and methyl iodide (CH3I). Fe@Pt selectively separates iodine species from seawater and groundwater with a removal efficiency ≥ 99.8%. The maximum adsorption capacity for the iodine atom of all three iodine species was determined to be 25 mg/g. The magnetic properties of Fe@Pt allow for the facile recovery and reuse of Fe@Pt, which remains stable with high efficiency (97.5%) over 100 uses without structural and functional degradation in liquid media. Practical application to the removal of radioactive 129I and feasibility for scale-up using a 20 L system demonstrate that Fe@Pt can function as a reusable adsorbent for the selective removal of iodine species. This systematic procedure is a standard protocol for designing highly active adsorbents for the clean separation and removal of various chemical species dissolved in wastewater.


Asunto(s)
Yodo , Neoplasias de la Tiroides , Contaminantes Químicos del Agua , Adsorción , Humanos , Yoduros , Radioisótopos de Yodo/química , Agua/química , Contaminantes Químicos del Agua/química
8.
Front Plant Sci ; 13: 858433, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35519818

RESUMEN

UV-A radiation (320-400 nm) is an abiotic stressor that may be used to enhance the production of beneficial secondary metabolites in crops such as leafy vegetables. However, tradeoffs between enhanced phytochemical contents and overall growth/yield reductions have been reported. The responses varied depending on the UV-A intensity, spectral peak, exposure time, species, and varieties. We quantified the changes in growth, morphology, photosynthesis, and phenolic contents of sweet basil grown under a base red/blue/green LED light with four supplemental UV-A intensity treatments (0, 10, 20, and 30 W·m-2) in an indoor environment over 14 days. The objective was to determine whether UV-A radiation could be utilized to improve both yield and quality of high-value sweet basil in a controlled production environment. Biomass harvested at 14 days after treatment (DAT) was highest under mild-intensity UV-A treatment of 10 W·m-2 and lowest under high-intensity UV-A treatment of 30 W·m-2. The total leaf area and the number of leaves were significantly lower under the 30 W·m-2 treatment than under the 10 and 20 W·m-2 treatments at 14 DAT. The maximum quantum efficiency of photosystem II (PSII) for photochemistry (Fv/Fm ) showed a gradual decrease under the 20 and 30 W·m-2 treatments from 3 to 14 DAT, whereas Fv/Fm remained relatively constant under the 0 and 10 W·m-2 treatments over the entire 14 days. The leaf net photosynthesis rate showed a significant decrease of 17.4% in the 30 W·m-2 treatment compared to that in the 10 W·m-2 treatment at 14 DAT. Phenolic contents (PAL enzyme activity, total phenolic concentration, and antioxidant capacity) were the highest under the 20 W·m-2 treatment, followed by the 10, 30, and 0 W·m-2 treatments. Overall, our results indicate that the biomass production and accumulation of beneficial phenolic compounds in sweet basil varied depending on the intensity and duration of UV-A application. Mild UV-A radiation (10-20 W·m-2) can be a beneficial stressor to improve sweet basil yield and quality over relatively long-term cultivation.

9.
Analyst ; 146(22): 6768-6779, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34642716

RESUMEN

Herein, we propose an array of gold (Au)-coated SU-8 cantilevers with microgrooves for improved maturation of cardiomyocytes and describe its applications to drug-induced cardiac toxicity tests. Firstly, we evaluated the effect of cell culture substrates such as polydimethylsiloxane (PDMS), polyimide (PI), and SU-8 on the cardiomyocyte's maturation. Among these, the SU-8 with microgroove structures exhibits improved cardiomyocyte maturation. Further, thin layers of graphene and Au are coated on SU-8 substrates and the effects of these materials on cardiomyocyte maturation are evaluated by analyzing the expression of proteins such as alpha-actinin, Connexin 43 (Cx43), and Vinculin. While both conductive materials enhanced protein expression when compared to bare SU-8, the Au-coated SU-8 substrates demonstrated superior cardiomyocyte maturation. The cantilever structure is constructed using microgroove patterned SU-8 with and without an Au coating. The Au-coated SU-8 cantilever showed maximum displacement of 17.6 ± 0.3 µm on day 21 compared to bare SU-8 (14.2 ± 0.4 µm) owing to improved cardiomyocytes maturation. Verapamil and quinidine are used to characterize drug-induced changes in the contraction characteristics of cardiomyocytes on bare and Au-coated SU-8 cantilevers. The relative contraction forces and beat rates changed according to the calcium and sodium channel related drugs. Matured cardiomyocytes are less influenced by the drugs compared to immature cardiomyocytes and showed reliable IC50 values. These results indicate that the proposed Au-coated SU-8 cantilever array could help improve the accuracy of toxicity screening results by allowing for the use of cardiomyocytes that have been matured on the drug screening platform.


Asunto(s)
Cardiotoxicidad , Preparaciones Farmacéuticas , Oro/toxicidad , Humanos , Contracción Miocárdica , Miocitos Cardíacos
10.
Inorg Chem ; 60(20): 15091-15095, 2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34585575

RESUMEN

We provide the material synthesis method, crystal structure information, and characterization of a novel mixed-valent metal oxide KIn0.33IIITe0.67VITe2IVO7, closely related to zirconolite (CaZrTi2O7), a radioactive waste immobilized material, having a 3D framework. The reported metal oxide containing an alkali-metal cation (K+), main-group cation (In3+), tellurate, and tellurite has been synthesized as both single crystals and a pure polycrystalline phase through a hydrothermal synthesis method. Single-crystal X-ray diffraction indicates that KIn0.33Te2.67O7 crystallizing in the orthorhombic space group Cmcm (No. 63) reveals a 3D framework structure with a 1D channel consisting of Te/InO6 octahedra and TeO4 polyhedra. An interesting transition reaction from KIn0.33Te2.67O7 to KIn(TeO3)2 under hydrothermal conditions at 230 °C is discussed.

11.
Sci Rep ; 10(1): 6650, 2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-32313259

RESUMEN

The coverage and temperature dependence of ZIRLO cladding with H2O adsorption are studied using synchrotron-based high-resolution photoemission spectroscopy (HRPES). Based on the analytical results of the Zr 3d, O 1 s, C 1 s, and Sn 3d HRPES profiles prior to H2O adsorption, we determine the surface compositions of O2-, hydroxyl OH-, chemisorbed H2O, zirconium carbide, adventitious carbon, Sn metal, and SnO2 in ZIRLO. When ZIRLO is exposed to H2O molecules, the relative proportion of zirconium metal decreases, whereas that of the total zirconium oxides increases, suggesting the reaction between H2O and the zirconium metal in ZIRLO. On annealing a sample with 1000 L H2O on ZIRLO at 300 °C, Zr2O3 and ZrO2 decompose, and oxygen diffuses into the bulk, thereby reducing the oxidation states of zirconium on the surface. Moreover, at this temperature, the excess H2O molecules on ZIRLO are thoroughly desorbed and tin element is diffused into the bulk in ZIRLO.

12.
Sensors (Basel) ; 19(14)2019 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-31336630

RESUMEN

This paper presents a detailed experimental assessment of Gaussian Process (GP) regression for air-to-ground communication channel prediction for relay missions in urban environment. Considering restrictions from outdoor urban flight experiments, a way to simulate complex urban environments at an indoor room scale is introduced. Since water significantly absorbs wireless communication signal, water containers are utilized to replace buildings in a real-world city. To evaluate the performance of the GP-based channel prediction approach, several indoor experiments in an artificial urban environment were conducted. The performance of the GP-based and empirical model-based prediction methods for a relay mission was evaluated by measuring and comparing the communication signal strength at the optimal relay position obtained from each method. The GP-based prediction approach shows an advantage over the model-based one as it provides a reasonable performance without a need for a priori information of the environment (e.g., 3D map of the city and communication model parameters) in dynamic urban environments.

13.
Sensors (Basel) ; 19(11)2019 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-31159481

RESUMEN

Due to payload restrictions for micro aerial vehicles (MAVs), vision-based approaches have been widely studied with their light weight characteristics and cost effectiveness. In particular, optical flow-based obstacle avoidance has proven to be one of the most efficient methods in terms of obstacle avoidance capabilities and computational load; however, existing approaches do not consider 3-D complex environments. In addition, most approaches are unable to deal with situations where there are wall-like frontal obstacles. Although some algorithms consider wall-like frontal obstacles, they cause a jitter or unnecessary motion. To address these limitations, this paper proposes a vision-based obstacle avoidance algorithm for MAVs using the optical flow in 3-D textured environments. The image obtained from a monocular camera is first split into two horizontal and vertical half planes. The desired heading direction and climb rate are then determined by comparing the sum of optical flows between half planes horizontally and vertically, respectively, for obstacle avoidance in 3-D environments. Besides, the proposed approach is capable of avoiding wall-like frontal obstacles by considering the divergence of the optical flow at the focus of expansion and navigating to the goal position using a sigmoid weighting function. The performance of the proposed algorithm was validated through numerical simulations and indoor flight experiments in various situations.

14.
J Proteomics ; 196: 120-130, 2019 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-29970347

RESUMEN

Previously, we reported a novel Magnaporthe oryzae- secreted protein MSP1, which triggers cell death and pathogen-associated molecular pattern (PAMP)-triggered immune (PTI) responses in rice. To investigate the MSP1 induced defense response in rice at the protein level, we employed a label-free quantitative proteomic approach, in parallel with flg22 treatment, which is a well-known elicitor. Exogenous application of MSP1 to rice leaves induced an oxidative burst, MAPK3/6 activation, and activation of pathogenesis-related genes (DUF26, PBZ, and PR-10). MaxQuant based label free proteome analysis led to the identification of 4167 protein groups of which 433 showed significant differences in response to MSP1 and/or flg22 treatment. Functional annotation of the differential proteins showed that majority of the proteins related to primary, secondary, and lipid metabolism were decreased, while proteins associated mainly with the stress response, post-translational modification and signaling were increased in abundance. Moreover, several peroxidases and receptor kinases were induced by both the elicitors, highlighting their involvement in MSP1 and flg22 induced signaling in rice. Taken together, the results reported here contribute to our understanding of MSP1 and flg22 triggered immune responses at the proteome level, thereby increasing our overall understanding of PTI signaling in rice. BIOLOGICAL SIGNIFICANCE: MSP1 is a M. oryzae secreted protein, which triggers defense responses in rice. Previous reports have shown that MSP1 is required for the pathogenicity of rice blast fungus, however, the exact mechanism of its action and its downstream targets in rice are currently unknown. Identification of the downstream targets is required in order to understand the MSP1 induced signaling in rice. Moreover, key proteins identified could also serve as potential candidates for the generation of disease resistance crops by modulating stress signaling pathways. Therefore, here we employed, for the first time, a label-free quantitative proteomic approach to investigate the MSP1 induced signaling in rice together with flg22. Functional annotation of the differential proteins showed that majority of the proteins related to primary, secondary, and lipid metabolism were decreased, while proteins related to the defense response, signaling and ROS detoxification were majorly increased. Thus, as an elicitor, recombinant MSP1 proteins could be utilized to inducing broad pathogen resistance in crops by priming the local immune responses.


Asunto(s)
Oryza/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Proteómica , Transducción de Señal/fisiología
15.
Inorg Chem ; 57(14): 8299-8306, 2018 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-29952559

RESUMEN

The electrochemical reduction of trivalent samarium in a LiCl-KCl eutectic melt produced highly stable divalent samarium, whose electrochemical properties and electronic structure in the molten salt were investigated using cyclic voltammetry, UV-vis absorption spectroscopy, laser-induced emission spectroscopy, and density functional theory (DFT) calculations. Diffusion coefficients of Sm2+ and Sm3+ were electrochemically measured to be 0.92 × 10-5 and 1.10 × 10-5 cm2/s, respectively, and the standard apparent potential of the Sm2+/3+ couple was estimated to be -0.82 V vs Ag|Ag+ at 450 °C. The spectroelectrochemical study demonstrated that the redox behavior of the samarium cations obeys the Nernst equation ( E°' = -0.83 V, n = 1) and the trivalent samarium cation was successfully converted to the divalent cation having characteristic absorption bands at 380 and 530 nm with molar absorptivity values of 1470 and 810 M-1 cm-1, respectively. Density function theory calculations for the divalent samarium complex revealed that the absorption signals originated from the 4f6 to 4f55d1 transitions. Additionally, laser-induced emission measurements for the Sm cations in the LiCl-KCl matrix showed that the Sm3+ ion in the LiCl-KCl melt at 450 °C emitted an orange color of fluorescence, whereas a red colored emission was observed from the Sm2+ ion in the solidified LCl-KCl salt at room temperature.

16.
Plant Cell Rep ; 37(6): 873-885, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29541882

RESUMEN

KEY MESSAGE: Pseudomonas nitroreducens: strain IHB B 13561 (PnIHB) enhances the growth of Arabidopsis thaliana and Lactuca sativa via the stimulation of cell development and nitrate absorption. Plant growth-promoting rhizobacteria (PGPR) enhance plant development through various mechanisms; they improve the uptake of soil resources by plants to greatly promote plant growth. Here, we used Arabidopsis thaliana seedlings and Lactuca sativa to screen the growth enhancement activities of a purified PGPR, Pseudomonas nitroreducens strain IHB B 13561 (PnIHB). When cocultivated with PnIHB, both species of plants exhibited notably improved growth, particularly in regard to biomass. Quantitative reverse transcription polymerase chain reaction analysis indicated high expression levels of the nitrate transporter genes, especially NRT2.1, which plays a major role in the high-affinity nitrate transport system in roots. Moreover, enhanced activity of the cyclin-B1 promoter was observed when wild-type 'Columbia-0' Arabidopsis seedlings were exposed to PnIHB, whereas upregulation of cyclin-B also occurred in the inoculated lettuce seedlings. Overall, these results suggest that PnIHB improves A. thaliana and L. sativa growth via specific pathways involved in the promotion of cell development and enhancement of nitrate uptake.


Asunto(s)
Proteínas de Transporte de Anión/metabolismo , Arabidopsis/microbiología , Regulación de la Expresión Génica de las Plantas , Lactuca/microbiología , Nitratos/metabolismo , Pseudomonas/fisiología , Proteínas de Transporte de Anión/genética , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Biomasa , Lactuca/genética , Lactuca/crecimiento & desarrollo , Transportadores de Nitrato , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Plantones/genética , Plantones/crecimiento & desarrollo , Plantones/microbiología , Suelo , Regulación hacia Arriba
17.
Mol Cells ; 41(4): 351-361, 2018 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-29487277

RESUMEN

Sucrose is a crucial compound for the growth and development of plants, and the regulation of multiple genes depends on the amount of soluble sugars present. Sucrose acts as a signaling molecule that regulates a proton-sucrose symporter, with its sensor being the sucrose transporter. Flavonoid and anthocyanin biosynthesis are regulated by sucrose, and sucrose signaling can affect flavonoid and anthocyanin accumulation. In the present study, we found a Myb transcription factor affecting accumulation of anthocyanin. AtMyb56 showed an increase in its expression in response to sucrose treatment. Under normal conditions, anthocyanin accumulation was similar between Col-0 (wild type) and atmyb56 mutant seedlings; however, under sucrose treatment, the level of anthocyanin accumulation was lower in the atmyb56 mutant plants than in Col-0 plants. Preliminary microarray analysis led to the investigation of the expression of one candidate gene, AtGPT2, in the atmyb56 mutant. The phosphate translocator, which is a plastidial phosphate antiporter family, catalyzes the import of glucose-6-phosphate (G-6-P) into the chloroplast. AtGPT2 gene expression was altered in atmyb56 seedlings in a sucrose-dependent manner in response to circadian cycle. Furthermore, the lack of AtMyb56 resulted in altered accumulation of maltose in a sucrose-dependent manner. Therefore, the sucrose responsive AtMyb56 regulates AtGPT2 gene expression in a sucrose-dependent manner to modulate maltose and anthocyanin accumulations in response to the circadian cycle.


Asunto(s)
Antocianinas/metabolismo , Proteínas de Arabidopsis/biosíntesis , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Transporte de Monosacáridos/biosíntesis , Sacarosa/metabolismo , Factores de Transcripción/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Transporte de Monosacáridos/genética , Transducción de Señal , Factores de Transcripción/genética
18.
Medicine (Baltimore) ; 95(47): e5467, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27893694

RESUMEN

This study aimed to evaluate the safety and efficacy of vitamin K antagonist (VKA) in atrial fibrillation (AF) patients with previous ulcer bleeding.In this multicenter, retrospective analysis, clinical outcomes of 754 AF patients with a history of ulcer bleeding were evaluated. After ulcer treatment, 458 patients (61%) were treated with VKA, and the outcomes were compared to 296 patients (39%) without VKA.VKA treatment significantly increased major bleeding (7.3%/year vs 3.2%/year, P < 0.001), and reduced major adverse cardiac events (MACE) (5.4%/year vs 10.0%/year, P < 0.001). Specifically, risk of gastrointestinal bleeding was significantly higher in the VKA group than no-VKA group (5.7%/year vs 2.6%/year, P < 0.001). Consequently, there was no difference in the incidence of composite of a MACE and major bleeding, between the 2 groups. In patients with time in the therapeutic range (TTR) ≥65%, VKA significantly decreased MACE (2.8%/year vs 10.0%/year, P < 0.001) without increasing major bleeding. Net clinical benefit model showed beneficial effects of VKA in patients with TTR ≥65%, and harmful effects in those with TTR < 55%.In AF patients with previous ulcer bleeding, VKA treatment did not improve clinical outcomes unless the international normalized ratio level was constantly maintained (TTR ≥65%), as the gastrointestinal bleeding (GIB) risk significantly increased.


Asunto(s)
Úlcera Péptica Hemorrágica/inducido químicamente , Vitamina K/antagonistas & inhibidores , Anciano , Fibrilación Atrial/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
19.
Int J Cardiol ; 214: 4-9, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27055157

RESUMEN

BACKGROUND: Systemic inflammation plays an important role in the pathogenesis of atrial fibrillation (AF). However, little evidence exists whether the risk of AF is increased in autoimmune rheumatic disease (ARD). METHODS: In 20,772 consecutive ARD patients (mean age 42±17years, 13,683 female) in a tertiary hospital from 2005 to 2015, AF prevalence, comorbidities and cardiovascular (CV) outcomes were evaluated. RESULTS: AF was observed in 235 (1.1%) patients. The mean duration to AF diagnoses was 5.9±2.4years. Compared with patients without AF, AF patients were older, and had a higher CRP level (5.1±0.7 vs. 2.7±0.2mg/L, p=0.01), higher incidence of hypertension, heart failure and coronary artery disease. The AF prevalence was higher in inflammatory myositis (3.5%) and systemic sclerosis (2.3%) than that in other ARDs (all p<0.05). In the multivariate analysis, the independent predictors of AF were an older age (HR 1.05, 95% CI: 1.04-1.06, p=0.01), hypertension (HR 2.28, 95% CI: 1.70-3.06, p<0.001), high CRP levels (HR 1.75, 95% CI: 1.07-2.86, p=0.04), and heart failure (HR 11.96, 95% CI: 8.13-17.60, p=0.03). During a mean follow-up period of 6.8±4.5years, ARD patients with AF had a higher all cause death (16.5% vs. 2.1%, p<0.001) and incidence of strokes (1.9% vs. 0.4%, p=0.001) than non-AF patients. CONCLUSIONS: The incidence of AF in ARD was affected by specific disease and an inflammatory status manifested by the CRP level. AF in ARD was related to a higher mortality and strokes mandating meticulous follow-up.


Asunto(s)
Fibrilación Atrial/epidemiología , Enfermedades Autoinmunes/epidemiología , Enfermedades Reumáticas/epidemiología , Adulto , Factores de Edad , Anciano , Fibrilación Atrial/metabolismo , Enfermedades Autoinmunes/metabolismo , Proteína C-Reactiva/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , República de Corea/epidemiología , Estudios Retrospectivos , Enfermedades Reumáticas/metabolismo , Factores de Riesgo , Centros de Atención Terciaria/estadística & datos numéricos
20.
Int J Cardiol ; 203: 372-8, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26539960

RESUMEN

BACKGROUND: The efficacy of oral anticoagulation therapy (OAT) has not been revealed in atrial fibrillation (AF) patients with newly diagnosed cancers. This study evaluated the thromboembolic and bleeding events in AF patients with malignancies according to OAT. METHODS AND RESULTS: In 2168 consecutive non-valvular AF patients with newly diagnosed malignancies, we analyzed the composite endpoints including major adverse cardiac events (MACEs) and major bleeding. Based on a propensity score matching, two groups with 690 matched pairs were created. Patient baseline characteristics were comparable between the matched groups. During a follow-up period of 3.9 ± 2.8 years, 72 (10%) and 65 (9%) patients had MACEs in the propensity score-matched OAT + and OAT − groups, respectively (p = 0.461). There was no significant difference in the major bleeding (10% vs. 8%, p = 0.300) and composite endpoints (18% vs. 16%, p = 0.181) between OAT + and OAT − patients. During the first year after the cancer diagnosis, 66 (48%) MACEs, 52 (41%) major bleedings, and 116 (49%) composite end points of all events occurred. The optimal international normalized ratio (2.0 to 3.0) level was achieved in only 85 (12%) patients. However, 1 year after cancer diagnosis, OAT + patients with the target therapeutic range of ≥ 60% demonstrated better cumulative survival free of composite end point than OAT − patients (p = 0.026). CONCLUSION: During the first year after the cancer diagnosis, OAT did not improve the composite end point because of poor INR control caused by cancer treatment. However, after 1 year after diagnosis of cancer, optimal anticoagulation significantly reduced the composite end point.


Asunto(s)
Anticoagulantes/efectos adversos , Fibrilación Atrial/tratamiento farmacológico , Hemorragia/inducido químicamente , Neoplasias/tratamiento farmacológico , Medición de Riesgo/métodos , Accidente Cerebrovascular/prevención & control , Administración Oral , Anciano , Anticoagulantes/administración & dosificación , Fibrilación Atrial/complicaciones , Femenino , Estudios de Seguimiento , Hemorragia/epidemiología , Humanos , Incidencia , Masculino , Neoplasias/complicaciones , República de Corea/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/etiología , Tasa de Supervivencia/tendencias , Factores de Tiempo
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