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1.
Plant J ; 115(1): 155-174, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37025008

RESUMEN

Salicylic acid (SA) plays important roles in different aspects of plant development, including root growth, where auxin is also a major player by means of its asymmetric distribution. However, the mechanism underlying the effect of SA on the development of rice roots remains poorly understood. Here, we show that SA inhibits rice root growth by interfering with auxin transport associated with the OsPIN3t- and clathrin-mediated gene regulatory network (GRN). SA inhibits root growth as well as Brefeldin A-sensitive trafficking through a non-canonical SA signaling mechanism. Transcriptome analysis of rice seedlings treated with SA revealed that the OsPIN3t auxin transporter is at the center of a GRN involving the coat protein clathrin. The root growth and endocytic trafficking in both the pin3t and clathrin heavy chain mutants were SA insensitivity. SA inhibitory effect on the endocytosis of OsPIN3t was dependent on clathrin; however, the root growth and endocytic trafficking mediated by tyrphostin A23 (TyrA23) were independent of the pin3t mutant under SA treatment. These data reveal that SA affects rice root growth through the convergence of transcriptional and non-SA signaling mechanisms involving OsPIN3t-mediated auxin transport and clathrin-mediated trafficking as key components.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Oryza , Clatrina/metabolismo , Proteínas de Arabidopsis/metabolismo , Oryza/metabolismo , Arabidopsis/genética , Ácido Salicílico/metabolismo , Raíces de Plantas/metabolismo , Transporte de Proteínas , Ácidos Indolacéticos/metabolismo
2.
Sensors (Basel) ; 24(14)2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39066120

RESUMEN

The next generation phased array radio telescopes, such as the Square Kilometre Array (SKA) low frequency aperture array, suffer from RF interference (RFI) because of the large field of view of antenna element. The classical station beamformer used in SKA-low is resource efficient but cannot deal with the unknown sidelobe RFI. A real-time adaptive beamforming strategy is proposed for SKA-low station, which trades the capability of adaptive RFI nulling at an acceptably cost, it doesn't require hardware redesign but only modifies the firmware accordingly. The proposed strategy uses a Parallel Least Mean Square (PLMS) algorithm, which has a computational complexity of 4N+2 and can be performed in parallel. Beam pattern and output SINR simulation results show deeply nulling performance to sidelobe RFI, as well as good mainlobe response similar to the classical beamformer. The convergence performance depends on the signal-and-interference environments and step size, wherein too large a step size leads to a non-optimal output SINR and too small a step size leads to slow convergence speed. FPGA implementation demonstrations are implemented and tested on a NI FPGA module, and test results demonstrate good real-time performance and low slice resource consumption.

3.
Biol Pharm Bull ; 46(1): 35-41, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36273899

RESUMEN

Pachymic acid (PA), exacted from Polyporaceae, has been known for its biological activities including diuretic, dormitive, anti-oxidant, anti-aging, anti-inflammatory and anticancer properties in several types of diseases. Recently, studies have demonstrated that PA could suppress cell growth and induce cell apoptosis in different kinds of cancer cells. But the underlying mechanisms remain poorly elucidated. In the current study, we investigated the effect of pachymic acid on liver cancer cells and its underlying mechanisms. Our results evidenced that pachymic acid effectively inhibited the cell growth and metastatic potential in HepG2 and Huh7 cells. Mechanistically, we revealed that pachymic acid triggered cell apoptosis by increasing caspase 3 and caspase 9 cleavage, upregulating Bax and cytochrome c expression, while reducing the expression of Bcl2. Besides, pachymic acid could markedly inhibit the cell invasion and migration and cell metastatic potential by mediating epithelial-to-mesenchymal transition (EMT) markers and metastasis-associated genes in HepG2 and Huh7 cells. In addition, we demonstrated that FAK-Src-Jun N-terminal kinase (JNK)-matrix metalloproteinase 2 (MMP2) axis was involved in PA-inhibited liver cell EMT. Together, these results contribute to our deeper understanding of the anti-cancer effects of pachymic acid on liver cancer cells. This study also provided compelling evidence that PA might be a potential therapeutic agent for liver cancer treatment.


Asunto(s)
Neoplasias Hepáticas , Metaloproteinasa 2 de la Matriz , Humanos , Metaloproteinasa 2 de la Matriz/genética , Línea Celular Tumoral , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Apoptosis , Transición Epitelial-Mesenquimal
4.
Angew Chem Int Ed Engl ; 59(47): 21049-21057, 2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-32767727

RESUMEN

Here, we describe a fluorination strategy for semiconducting polymers for the development of highly bright second near-infrared region (NIR-II) probes. Tetrafluorination yielded a fluorescence QY of 3.2 % for the polymer dots (Pdots), over a 3-fold enhancement compared to non-fluorinated counterparts. The fluorescence enhancement was attributable to a nanoscale fluorous effect in the Pdots that maintained the molecular planarity and minimized the structure distortion between the excited state and ground state, thus reducing the nonradiative relaxations. By performing through-skull and through-scalp imaging of the brain vasculature of live mice, we quantitatively analyzed the vascular morphology of transgenic brain tumors in terms of the vessel lengths, vessel branches, and vessel symmetry, which showed statistically significant differences from the wild type animals. The bright NIR-II Pdots obtained through fluorination chemistry provide insightful information for precise diagnosis of the malignancy of the brain tumor.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Fluorescencia , Colorantes Fluorescentes/química , Imagen Óptica , Polímeros/química , Puntos Cuánticos/química , Animales , Halogenación , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Tamaño de la Partícula , Semiconductores , Propiedades de Superficie
5.
Org Biomol Chem ; 15(38): 8134-8139, 2017 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-28905973

RESUMEN

A general and mild method for the construction of a carbon-nitrogen bond via copper-catalyzed oxidative cross-coupling of amines with α-aminocarbonyl compounds was achieved. Amines, either aliphatic primary amines, aromatic primary amines or secondary amines can be used as the starting materials. When R2 was different from R3, two isomers would be observed. Therefore, this reaction system has a broad substrate scope and provides a facile pathway for the synthesis of 2-oxo-acetamidines.

6.
Ecotoxicol Environ Saf ; 130: 93-102, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27088622

RESUMEN

Bisphenol A (BPA) is a well-known endocrine disrupting chemical (EDC), ubiquitous in the aquatic environment, which poses an ecotoxicological risk to the health of aquatic organisms. However, the immunotoxic effects of its long-term exposure on fish have received limited attention. We examined a number of typical immune-related parameters and oxidative stress indices in the liver and blood serum of the red common carp (Cyprinus carpio), following a 30-day exposure to five different concentrations of BPA (0.1, 1, 10, 100, and 1000µg/L). A significant increase in the hepato somatic index was observed in fish upon exposure to 1000µg/L BPA, which correlated strongly with the accumulated BPA concentrations in fish bile. Induced oxidative stress was also apparent in the exposed fish liver, based on the enhanced levels of lipid peroxidation and inhibited activities of catalase, superoxide dismutase, and glutathione peroxidase. Serum lysozyme and C-reaction protein levels increased at low concentrations of exposure; however, they were significantly suppressed upon exposure to high concentrations. A significant increase was observed in the levels of immunoglobulin M, complement component 3, and alkaline phosphatase, in both fish liver and serum at low doses of 0.1 and 1µg/L. This suggests that long-term exposure to environmentally relevant concentrations of BPA (even as low as 0.1µg/L) could significantly disturb the immune response of fish. Moreover, RXRα expression in the liver was significantly altered upon BPA exposure and the trend underlying this change correlated closely with those of the most immune-related parameters, implying the involvement of the PPARγ/RXRα signaling pathway in regulating the immune response of fish upon long-term BPA exposure. In short, our results demonstrate the susceptibility of fish immune system to long-term BPA exposure. Therefore, the immunotoxicity of EDCs in aquatic organisms should not have been underestimated.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Carpas/fisiología , Disruptores Endocrinos/toxicidad , Inmunidad/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Fenoles/toxicidad , Contaminantes Químicos del Agua/toxicidad , Fosfatasa Alcalina/metabolismo , Animales , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Proteína C-Reactiva/metabolismo , Carpas/inmunología , Carpas/metabolismo , Catalasa/metabolismo , Glutatión Peroxidasa/metabolismo , Inmunidad/fisiología , Inmunoglobulina M/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/enzimología , Muramidasa/sangre , Estrés Oxidativo/inmunología , Albúmina Sérica/metabolismo , Superóxido Dismutasa/metabolismo
7.
Sensors (Basel) ; 15(1): 1964-97, 2015 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-25602270

RESUMEN

Interference alignment (IA) has been put forward as a promising technique which can mitigate interference and effectively increase the throughput of wireless sensor networks (WSNs). However, the number of users is strictly restricted by the IA feasibility condition, and the interference leakage will become so strong that the quality of service will degrade significantly when there are more users than that IA can support. In this paper, a novel joint spatial-code clustered (JSCC)-IA scheme is proposed to solve this problem. In the proposed scheme, the users are clustered into several groups so that feasible IA can be achieved within each group. In addition, each group is assigned a pseudo noise (PN) code in order to suppress the inter-group interference via the code dimension. The analytical bit error rate (BER) expressions of the proposed JSCC-IA scheme are formulated for the systems with identical and different propagation delays, respectively. To further improve the performance of the JSCC-IA scheme in asymmetric networks, a random grouping selection (RGS) algorithm is developed to search for better grouping combinations. Numerical results demonstrate that the proposed JSCC-IA scheme is capable of accommodating many more users to communicate simultaneously in the same frequency band with better performance.


Asunto(s)
Redes de Comunicación de Computadores , Tecnología Inalámbrica , Algoritmos , Análisis por Conglomerados , Análisis Numérico Asistido por Computador
8.
Sensors (Basel) ; 15(8): 18526-49, 2015 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-26230697

RESUMEN

Interference alignment (IA) is a novel technique that can effectively eliminate the interference and approach the sum capacity of wireless sensor networks (WSNs) when the signal-to-noise ratio (SNR) is high, by casting the desired signal and interference into different signal subspaces. The traditional alternating minimization interference leakage (AMIL) algorithm for IA shows good performance in high SNR regimes, however, the complexity of the AMIL algorithm increases dramatically as the number of users and antennas increases, posing limits to its applications in the practical systems. In this paper, a novel IA algorithm, called directional quartic optimal (DQO) algorithm, is proposed to minimize the interference leakage with rapid convergence and low complexity. The properties of the AMIL algorithm are investigated, and it is discovered that the difference between the two consecutive iteration results of the AMIL algorithm will approximately point to the convergence solution when the precoding and decoding matrices obtained from the intermediate iterations are sufficiently close to their convergence values. Based on this important property, the proposed DQO algorithm employs the line search procedure so that it can converge to the destination directly. In addition, the optimal step size can be determined analytically by optimizing a quartic function. Numerical results show that the proposed DQO algorithm can suppress the interference leakage more rapidly than the traditional AMIL algorithm, and can achieve the same level of sum rate as that of AMIL algorithm with far less iterations and execution time.

9.
ScientificWorldJournal ; 2014: 481312, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24782661

RESUMEN

A fast and robust ellipse-detection method based on sorted merging is proposed in this paper. This method first represents the edge bitmap approximately with a set of line segments and then gradually merges the line segments into elliptical arcs and ellipses. To achieve high accuracy, a sorted merging strategy is proposed: the merging degrees of line segments/elliptical arcs are estimated, and line segments/elliptical arcs are merged in descending order of the merging degrees, which significantly improves the merging accuracy. During the merging process, multiple properties of ellipses are utilized to filter line segment/elliptical arc pairs, making the method very efficient. In addition, an ellipse-fitting method is proposed that restricts the maximum ratio of the semimajor axis and the semiminor axis, further improving the merging accuracy. Experimental results indicate that the proposed method is robust to outliers, noise, and partial occlusion and is fast enough for real-time applications.


Asunto(s)
Modelos Teóricos , Algoritmos
10.
Nat Commun ; 15(1): 3437, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38653755

RESUMEN

Phytoalexin sakuranetin functions in resistance against rice blast. However, the mechanisms underlying the effects of sakuranetin remains elusive. Here, we report that rice lines expressing resistance (R) genes were found to contain high levels of sakuranetin, which correlates with attenuated endocytic trafficking of plasma membrane (PM) proteins. Exogenous and endogenous sakuranetin attenuates the endocytosis of various PM proteins and the fungal effector PWL2. Moreover, accumulation of the avirulence protein AvrCO39, resulting from uptake into rice cells by Magnaporthe oryzae, was reduced following treatment with sakuranetin. Pharmacological manipulation of clathrin-mediated endocytic (CME) suggests that this pathway is targeted by sakuranetin. Indeed, attenuation of CME by sakuranetin is sufficient to convey resistance against rice blast. Our data reveals a mechanism of rice against M. oryzae by increasing sakuranetin levels and repressing the CME of pathogen effectors, which is distinct from the action of many R genes that mainly function by modulating transcription.


Asunto(s)
Ascomicetos , Resistencia a la Enfermedad , Endocitosis , Flavonoides , Oryza , Fitoalexinas , Enfermedades de las Plantas , Proteínas de Plantas , Oryza/microbiología , Oryza/metabolismo , Oryza/efectos de los fármacos , Oryza/genética , Enfermedades de las Plantas/microbiología , Endocitosis/efectos de los fármacos , Resistencia a la Enfermedad/genética , Resistencia a la Enfermedad/efectos de los fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Sesquiterpenos/farmacología , Sesquiterpenos/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/efectos de los fármacos , Plantas Modificadas Genéticamente , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética
11.
Int J Biol Macromol ; 253(Pt 1): 126628, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37657582

RESUMEN

Recently, using oxidized regenerated cellulose (ORC) to build a hydrogel system on promoting healing in wounds has a fast-growing market. However, it remains a challenge to improve the degree of oxidation of regenerated cellulose (RC) and to prepare matrices that are uniquely responsive to the wound environment. Herein, highly oxidized aldehyde-based cellulose from porous RC was prepared by NaBH4-HCl swelling and then NaIO4 oxidation pathway. Chitosan (CS), ethylenediamine-cyclodextrin (EDA-CD) along with ORC have been used to construct hydrogel matrices that are pH-responsive and capable of controlled drug release for use as future wound dressings. And zinc oxide nanoparticles (ZnO NPs) with antimicrobial effect and ibuprofen (IBU) with analgesic effect were piggybacked into the hydrogel system. XRD was used to study the presence of ZnO. SEM was used to observe the surface structure of the prepared hydrogel. TEM was used to observe the particle size of the ZnO NPs. Meanwhile, the oxidation conditions of the ORC were explored. Furthermore, the mechanical, swelling, water retention, cytotoxicity, bacterial inhibition properties and treatment effect, which are closely related to the application of wound dressing, were carefully researched. The unique characteristics of prepared hydrogel, including pH-responsive degradability and sustained release properties of IBU, were also investigated.


Asunto(s)
Celulosa Oxidada , Quitosano , Óxido de Zinc , Hidrogeles/química , Óxido de Zinc/química , Quitosano/química , Ibuprofeno/farmacología , Vendajes , Concentración de Iones de Hidrógeno , Antibacterianos/farmacología , Antibacterianos/química
12.
Am Surg ; : 31348231158692, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36803027

RESUMEN

BACKGROUND: The incidence of postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD) is high. We sought to develop a POPF prediction model based on a decision tree (DT) and random forest (RF) algorithm after PD and to explore its clinical value. METHODS: The case data of 257 patients who underwent PD in a tertiary general hospital from 2013 to 2021 were retrospectively collected in China. The RF model was used to select features by ranking the importance of variables, and both algorithms were used to build the prediction model after automatic adjustment of parameters by setting the respective hyperparameter intervals and resampling as a 10-fold cross-validation method, etc. The prediction model's performance was assessed by the receiver operating characteristic curve (ROC) and the area under curve (AUC). RESULTS: Postoperative pancreatic fistula occurred in 56 cases (56/257, 21.8%). The DT model had an AUC of .743 and an accuracy of .840, while the RF model had an AUC of .977 and an accuracy of .883. The DT plot visualized the process of inferring the risk of pancreatic fistula from the DT model on independent individuals. The top 10 important variables were selected for ranking in the RF variable importance ranking. CONCLUSION: This study successfully developed a DT and RF algorithm for the POPF prediction model, which can be used as a reference for clinical health care professionals to optimize treatment strategies to reduce the incidence of POPF.

13.
Chem Commun (Camb) ; 58(94): 13087-13090, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36341944

RESUMEN

We present the synthesis and characterization of the first triple oxa[6]helicene with C3 symmetry. In contrast to the reported D3-symmetric triple oxa[7]helicene, the C3-symmetric analogue holds parallel electric and magnetic transition dipole moments and thus enhanced luminescence dissymmetry, shedding light on the critical role of molecular symmetry on chiroptical response.

14.
Chemosphere ; 287(Pt 4): 132434, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34606890

RESUMEN

Fluoxetine (FLU), a selective serotonin reuptake inhibitor, is commonly found in aquatic environments. Ultraviolet (UV) photolysis is widely used to remove certain pharmaceuticals from water and wastewater. The present study aimed to investigate the toxicity of FLU and its transformed products formed during UV photolysis by using zebrafish embryos (Danio rerio) as a model. The degradation rates of FLU for five days were approximately 63.6% ± 2.14%, 84.6% ± 0.99%, and 97.5% ± 0.25% after 15, 30, and 60 min of UV irradiation, respectively. Furthermore, the degradation mechanism was explored using LC-MS measurements and density flooding theory (DFT) theoretical calculations. Comprehensive toxicity preassessment of FLU and its degradation products was carried out using the T.E.S.T. software. The effects of physiological and biochemical parameters and neuron- and apoptosis-related gene expression were examined in zebrafish embryos exposed to non-irradiated (0-min) and irradiated (15, 30- and 60-min) solutions from 4 h post-fertilization (hpf) to 120 hpf. The hatching time of zebrafish embryos exposed to the non-irradiated solution (0-min) and irradiated solution (60-min) was delayed, their heart rate at 48 and 72 hpf increased, and their body length at 120 hpf decreased. Significant differences were found between the non-irradiated (0-min) and UV-irradiated (15- or 30-min) groups. A dynamic response involving acetylcholinesterase (AChE) and superoxide dismutase (SOD) activity was also observed in the non-irradiated and UV-irradiated groups. During the UV treatment experiments, the expression levels of neuron-related and apoptosis-related genes were significantly reduced over time alongside the formation of FLU degradation products. Overall, this study provides new concepts to remove and assess the toxicity of emerging contaminants in aquatic environments and highlights the need to consider the formation and persistence of toxic transformation products.


Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Acetilcolinesterasa , Animales , Antidepresivos , Embrión no Mamífero , Fluoxetina/toxicidad , Agua , Contaminantes Químicos del Agua/toxicidad
15.
Front Plant Sci ; 13: 961658, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36147240

RESUMEN

Root system architecture (RSA) and tiller are important agronomic traits. However, the mechanisms of the IGT family genes regulate RSA and tiller development in different rice varieties remain unclear. In this study, we demonstrated that 38 rice varieties obtained from Yuanyang Hani's terraced fields with different RSA and could be classified into six groups based on the ratio of root length and width. We found a positive correlation between RSA (including root width, length, and area) and tiller number in most of rice varieties. Furthermore, the IGT family genes Deeper Rooting 1 (DRO1), LAZY1, TAC1, and qSOR1 showed different expression patterns when rice grown under irrigation and drought conditions. Moreover, the qSOR1 gene had higher levels in the roots and tillers, and accompanied with higher levels of PIN1b gene in roots when rice grown under drought environmental condition. DRO1 gene had two single nucleotide polymorphisms (SNPs) in the exon 3 sequences and showed different expression patterns in the roots and tillers of the 38 rice varieties. Overexpression of DRO1 with a deletion of exon 5 caused shorter root length, less lateral roots and lower levels of LAZY1, TAC1, and qSOR1. Further protein interaction network, microRNA targeting and co-expression analysis showed that DRO1 plays a critical role in the root and tiller development associated with auxin transport. These data suggest that the RSA and tiller development are regulated by the IGT family genes in an intricate network way, which is tightly related to rice genetic background in rice adapting to different environmental conditions.

16.
J Int Med Res ; 49(10): 3000605211053554, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34674565

RESUMEN

Small bowel volvulus secondary to Meckel's diverticulum is rare, and a delayed diagnosis results in disastrous outcomes. Computed tomography is conducive to early differential diagnosis. In particular, a blind-ending pouch structure on CT always indicates Meckel's diverticulum. Diverticulectomy with or without adjacent partial small intestinal resection is the standard treatment for symptomatic Meckel's diverticulum. However, the therapy for asymptomatic Meckel's diverticulum is controversial. Here, we report the case of a 20-year-old man who suffered intestinal obstruction secondary to small bowel volvulus caused by an axially torsional, gangrenous, and giant Meckel's diverticulum. Diverticulectomy with partial intestinal resection was performed.


Asunto(s)
Obstrucción Intestinal , Vólvulo Intestinal , Divertículo Ileal , Adulto , Anastomosis Quirúrgica , Humanos , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Vólvulo Intestinal/complicaciones , Vólvulo Intestinal/diagnóstico por imagen , Vólvulo Intestinal/cirugía , Masculino , Divertículo Ileal/complicaciones , Divertículo Ileal/diagnóstico por imagen , Divertículo Ileal/cirugía , Tomografía Computarizada por Rayos X , Adulto Joven
17.
JGH Open ; 5(6): 720-721, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34124392

RESUMEN

Combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CC) is a rare subtype in primary liver cancer, which is difficult to diagnose in clinics. In this report, we present a case of a 62-year-old male with abdominal pain and slightly elevated alpha-fetoprotein. The contrast-enhanced computed tomography scans showed a left liver mass, which showed adherence to the imaging characteristics of hepatocellular carcinoma. However, with the treatment of laparoscopic liver resection, the following histological examination displayed two distinct components, which were consistent with the diagnosis of cHCC-CC.

18.
Adv Mater ; 33(39): e2101844, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34365677

RESUMEN

Persistent luminescence from triplet excitons in organic molecules is rare, as fast non-radiative deactivation typically dominates over radiative transitions. This work demonstrates that the substitution of a hydrogen atom in a derivative of phenanthroimidazole with an N-phenyl ring can substantially stabilize the excited state. This stabilization converts an organic material without phosphorescence emission into a molecular system exhibiting efficient and ultralong afterglow phosphorescence at room temperature. Results from systematic photophysical investigations, kinetic modeling, excited-state dynamic modeling, and single-crystal structure analysis identify that the long-lived triplets originate from a reduction of intrinsic non-radiative molecular relaxations. Further modification of the N-phenyl ring with halogen atoms affects the afterglow lifetime and quantum yield. As a proof-of-concept, an anticounterfeiting device is demonstrated with a time-dependent Morse code feature for data encryption based on these emitters. A fundamental design principle is outlined to achieve long-lived and emissive triplet states by suppressing intrinsic non-radiative relaxations in the form of molecular vibrations or rotations.

19.
Plant Sci ; 296: 110472, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32540002

RESUMEN

Cytosolic Ca2+ increases in response to many stimuli. CAX1 (H+/Ca2+ exchanger 1) maintains calcium homeostasis by transporting calcium from the cytosol to vacuoles. Here, we determined that the cax1 mutant exhibits enhanced resistance against both an avirulent biotrophic pathogen Pst-avrRpm1 (Pseudomonas syringae pv tomato DC3000 avrRpm1), and a necrotrophic pathogen, B. cinerea (Botrytis cinerea). The defense hormone SA (salicylic acid) and phytoalexin scopoletin, which fight against biotrophs and necrotrophs respectively, accumulated more in cax1 than wild-type. Moreover, the cax1 mutant exhibited early senescence after exogenous Ca2+ application. The accelerated senescence in the cax1 mutant was dependent on SID2 (salicylic acid induction deficient 2) but not on NPR1 (nonexpressor of pathogenesis-related genes1). Additionally, the introduction of CAX1 into the cax1 mutant resulted in phenotypes similar to that of wild-type in terms of Ca2+-conditioned senescence and Pst-avrRpm1 and B. cinerea infections. However, disruption of CAX3, the homolog of CAX1, did not produce an obvious phenotype. Moreover, exogenous Ca2+ application on plants resulted in increased resistance to both Pst-avrRpm1 and B. cinerea. Therefore, we conclude that the disruption of CAX1, but not CAX3, causes the activation of pathogen defense mechanisms, probably through the manipulation of calcium homeostasis or other signals.


Asunto(s)
Antiportadores/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Calcio/metabolismo , Proteínas de Transporte de Catión/metabolismo , Resistencia a la Enfermedad , Envejecimiento , Antiportadores/fisiología , Arabidopsis/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/fisiología , Proteínas de Transporte de Catión/fisiología , Cromatografía de Gases y Espectrometría de Masas , Protones , Reacción en Cadena en Tiempo Real de la Polimerasa , Ácido Salicílico/metabolismo , Escopoletina/metabolismo
20.
Medicine (Baltimore) ; 99(20): e19948, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32443296

RESUMEN

There are limited systematic studies on hematologic disease complicated by air leak syndrome (ALS). Physicians in radiology departments and hematology departments have a limited awareness of ALS.The aim of this study was to explore the similarities and differences in clinical data between the clinical group and imaging group in patients with hematologic disease complicated by ALS.Clinical and CT data for 59 patients with hematologic disease complicated by ALS in our hospital were retrospectively reviewed. Patients were assessed by clinical grouping and image grouping. Data were compared between groups, and P < .05 was considered statistically significant.Dyspnea occurred more often in the allo-HSCT (allogeneic hematopoietic stem cell transplantation) group than that in the non-allo-HSCT group (68.8% vs 4.7%, P < .001), there were statistically significant differences in inducing factors between groups, and differences in other aspects were not statistically significant. Chest tightness and dyspnea occurred more often in the allo-HSCT with BO/BOOP (bronchiolitis Obliteran/bronchiolitis obliterans organizing pneumonia) group than those in the allo-HSCT without BO/BOOP group (80.0% vs 9.1%, P = .013), and differences in other aspects were not statistically significant. Chest pain occurred more often in the HPT (hydropneumothorax) group than that in the other 3 groups (pure pneumothorax [PT], pulmonary interstitial emphysema [PIE], complex ALS) (71.4% vs 11.1%, 0.0%, and 26.5%, P = .005); ALS thickness in the HPT group was greater than that in the other 2 groups (PIE and complex ALS) (19.7 vs 3.5 cm and 9.5 cm, P = .001); catheter drainage occurred more often in the HPT group than that in the other three groups (PT, PIE, complexALS) (64.3% vs 22.2%, 0.0%, and 2.9%, P = .001).ALS is a high risk in male patients who have a low BMI, have leukemia as a basic disease, and have basic lung diseases (eg, BO/BOOP). CT types are mainly complex ALS, HPT, and pure PT. In addition, clinical symptoms for patients in the HPT group are severe, and there is a high prevalence of catheter drainage.


Asunto(s)
Enfermedades Hematológicas/complicaciones , Enfisema Mediastínico/diagnóstico por imagen , Neumotórax/diagnóstico por imagen , Enfisema Pulmonar/diagnóstico por imagen , Adolescente , Adulto , Niño , Neumonía en Organización Criptogénica/complicaciones , Femenino , Enfermedades Hematológicas/diagnóstico por imagen , Enfermedades Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Masculino , Enfisema Mediastínico/etiología , Persona de Mediana Edad , Neumotórax/etiología , Enfisema Pulmonar/etiología , Estudios Retrospectivos , Adulto Joven
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