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1.
Int J Biol Macromol ; 258(Pt 2): 129110, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38161016

RESUMEN

Polymer modification using silicone rubber represents a promising avenue for enhancing physico-mechanical properties. However, achieving optimal performance through direct blending is hindered by the poor interface compatibility between silicone rubber and the matrix. In this study, we prepared super-tough thermoplastic vulcanizates (TPVs) of polylactic acid/silicone rubber through dynamic vulcanization with PLA, methyl vinyl silicone rubber (MVQ), glycidyl methacrylate grafted MVQ (MVQ-g-GMA), and fumed silica nanoparticles (SiO2). The impact of the SiO2 addition in MVQ on the morphology, mechanical properties, crystallization, and thermal properties of the TPVs was investigated. The results showed that MVQ-g-GMA and SiO2 exhibited a synergistic compatibilization effect significantly improving the interfacial adhesion between PLA and MVQ. Therefore, the impact and tensile strength of the TPVs increased from 8.0 kJ/m2 and 22.2 MPa to 62.6 kJ/m2 and 36.7 MPa, respectively. Moreover, the TPVs also presented good low-temperature toughness with a maximum impact strength of 40.4 kJ/m2 at -20 °C. Additionally, improvements in thermal stability and crystallization rate were also observed. Overall, combining organic and inorganic synergistic compatibilization is a feasible and effective method to fabricate outstanding low-temperature toughness to PLA.


Asunto(s)
Dióxido de Silicio , Elastómeros de Silicona , Poliésteres , Polímeros
2.
Phys Rev Lett ; 130(15): 153602, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37115881

RESUMEN

Recent experimental advances in creating dissipative couplings provide a new route for engineering exotic lattice systems and exploring topological dissipation. Using the spatial lattice of atomic spin waves in a vacuum vapor cell, where purely dissipative couplings arise from diffusion of atoms, we experimentally realize a dissipative version of the Su-Schrieffer-Heeger (SSH) model. We construct the dissipation spectrum of the topological or trivial lattices via electromagnetically induced-transparency spectroscopy. The topological dissipation spectrum is found to exhibit edge modes within a dissipative gap. We validate chiral symmetry of the dissipative SSH couplings and also probe topological features of the generalized dissipative SSH model. This work paves the way for realizing non-Hermitian topological quantum optics via dissipative couplings.

3.
Ecotoxicol Environ Saf ; 254: 114745, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36950991

RESUMEN

The toxic effects of micro(nano)plastics are long-standing, flourishing and fadeless as a research topic because of its' underlying threats to the ecology and human health. Nevertheless, in most of the existing studies, some model organisms are exposed to micro(nano)plastics at a high concentration unlikely to occur in the real environment, and there is limited data available on the impact of micro(nano)plastics at environmentally relevant concentrations (ERC) on environmental organisms. To gain a better insight into micro(nano)plastic toxicity to the environmental organisms, here we integrate the related publications of micro(nano)plastic research at ERC in the past 10 years using a bibliometric analysis, and focus on the analysis of publication trends, research focuses, collaborations, and research status. In addition, we further analyze the 33 final filtered literature, and elucidate the organismal response to micro(nano)plastics at ERC from the perspective of in vivo toxic effects and mechanisms involved. This paper also puts forward some limitations of the current study and some suggestions for future research. Our study may be of great significance in further understanding the ecotoxicity of micro(nano)plastics.


Asunto(s)
Plásticos , Contaminantes Químicos del Agua , Humanos , Plásticos/análisis , Ecología , Contaminantes Químicos del Agua/análisis
4.
Artículo en Inglés | MEDLINE | ID: mdl-36833533

RESUMEN

Background: This article provides an overview of the current status and research progress of mesothelioma. Methods: A total of 2638 documents published from 1 January 2004 to 30 November 2022 were retrieved from the Web of Science Core Collection and analyzed via Microsoft Office Excel 2019, VOSviewer 1.6.18, and Tableau 2022.2. Results: There was an obvious increase in the number of publications regarding mesothelioma in the last 18 years, with the United States dominating the research field with 715 publications and 23,882 citations, while the University of Turin contributed the most (118). Occupational & Environmental Medicine was the most popular journal (80), with Corrado Magnani being the most prolific author (52) and Michele Carbone obtaining the most citations (4472). "Oncology" and "Health Science of Environment & Occupation" were the two main subjects, while the keywords "asbestos", "lung cancer", "gene expression", "apoptosis", "survival", and "cisplatin" were the most popular. Conclusions: The containment of mesothelioma calls for more participation from low- and middle-income countries, and further attention needs to be paid to clinical research.


Asunto(s)
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Humanos , Lugar de Trabajo , Bibliometría
5.
New Phytol ; 238(2): 765-780, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36653958

RESUMEN

Metabolites including antibiotics, enzymes, and volatiles produced by plant-associated bacteria are key factors in plant-microbiota interaction that regulates various plant biological processes. There should be crucial mediators responsible for their entry into host plants. However, less is known about the identities of these plant transporters. We report that the Arabidopsis Nitrate Transporter1 (NRT1)/NPF protein NPF2.13 functions in plant uptake of tunicamycin (TM), a natural antibiotic produced by several Streptomyces spp., which inhibits protein N-glycosylation. Loss of NPF2.13 function resulted in enhanced TM tolerance, whereas NPF2.13 overexpression led to TM hypersensitivity. Transport assays confirmed that NPF2.13 is a H+ /TM symporter and the transport is not affected by other substrates like nitrate. NPF2.13 exclusively showed TM transport activity among tested NPFs. Tunicamycin uptake from TM-producing Streptomyces upregulated the expression of nitrate-related genes including NPF2.13. Moreover, nitrate allocation to younger leaves was promoted by TM in host plants. Tunicamycin could also benefit plant defense against the pathogen. Notably, the TM effects were significantly repressed in npf2.13 mutant. Overall, this study identifies NPF2.13 protein as an important TM transporter in plant-microbe interaction and provides insights into multiple facets of NPF proteins in modulating plant nutrition and defense by transporting exterior bacterial metabolites.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Plantas/metabolismo , Tunicamicina/farmacología , Nitratos/metabolismo , Proteínas de Transporte de Anión/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas
6.
Front Neurosci ; 16: 1026127, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36466171

RESUMEN

The purpose of this study was to assess the efficacy and safety of the combination of tirofiban with intravenous thrombolysis (IVT) in treating patients with capsular warning syndrome (CWS) who failed to respond to the treatment of intravenous thrombolysis alone. Tirofiban was approved for the treatment of CWS patients with fluctuating symptoms or no substantial improvement after intravenous thrombolysis within 24 h in our hospital from October 2019 to June 2021. Patients were evaluated with the National Institutes of Health Stroke Scale (NIHSS) at admission, at 72 h post-thrombolysis, at 1-week, and at 3-months with the modified Rankin Scales (MRS) score. A total of 12 patients received tirofiban and eight patients received control treatment with a history of CWS in our cohort. Among the patients, 13 patients smoked more than one pack of cigarettes a day, 17 had hypertension, 17 had hypercholesterolemia, 7 had diabetes, 1 had the history of cerebral infarction, 2 had atrial fibrillation, 7 had mild big vascular stenosis, 13 had lesions of the perforating branch by imaging, and 19 had acute capsular infarction. In both the tirofiban and control groups, NIHSS scores were significantly reduced after intravenous thrombolysis or 1-week after onset compared with before intravenous thrombolysis (P < 0.001). Before and after intravenous thrombolysis, there were no differences between the tirofiban group and control group (P = 0.970, P = 0.384, respectively). The tirofiban group, however, showed remarkably lower scores in both 1-week NIHSS and 3-month MRS than the control (P = 0.012, P = 0.003, respectively). Our study revealed that tirofiban did not increase the risk of hemorrhage and had favorable clinical efficacy as a remedial treatment for CWS patients with poor prognosis for intravenous thrombolysis, therefore indicating great potential for broader use.

7.
Int J Gen Med ; 15: 8191-8200, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36411815

RESUMEN

Introduction: There is no effective treatment plan for coronavirus disease 2019 (COVID-19). We employed a combination of Chinese and Western medicine treatment for some COVID-19 inpatients. Methods: This study was a prospective cohort study that observed non-critical COVID-19 inpatients. The differences will be observed in the time from admission to two consecutive 2019-nCoV nucleic acid test negatives and the Visual Analog Scale (VAS) score between the two groups. Results: A total of 254 confirmed COVID-19 patients were included in this study. The median time from the admission to two consecutive negative nucleic acid tests was 14 days for the integrated Chinese and Western Medicine (ICWM) group, while the Western Medicine (WM) group was 16 days. Besides, the median VAS score of the ICWM group was 0, which was an average decrease of 2 points compared to the time of admission. Conclusion: For non-critical COVID-19 patients, it was safe and have more benefits to add traditional Chinese medicine decoction based on WM treatment.

8.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33526703

RESUMEN

The gaseous phytohormone ethylene mediates numerous aspects of plant growth and development as well as stress responses. The F-box proteins EIN3-binding F-box protein 1 (EBF1) and EBF2 are key components that ubiquitinate and degrade the master transcription factors ethylene insensitive 3 (EIN3) and EIN3-like 1 (EIL1) in the ethylene response pathway. Notably, EBF1 and EBF2 themselves undergo the 26S proteasome-mediated proteolysis induced by ethylene and other stress signals. However, despite their importance, little is known about the mechanisms regulating the degradation of these proteins. Here, we show that a really interesting new gene (RING)-type E3 ligase, salt- and drought-induced ring finger 1 (SDIR1), positively regulates the ethylene response and promotes the accumulation of EIN3. Further analyses indicate that SDIR1 directly interacts with EBF1/EBF2 and targets them for ubiquitination and proteasome-dependent degradation. We show that SDIR1 is required for the fine tuning of the ethylene response to ambient temperature changes by mediating temperature-induced EBF1/EBF2 degradation and EIN3 accumulation. Thus, our work demonstrates that SDIR1 functions as an important modulator of ethylene signaling in response to ambient temperature changes, thereby enabling plant adaptation under fluctuating environmental conditions.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Unión al ADN/genética , Proteínas F-Box/genética , Factores de Transcripción/genética , Ubiquitina-Proteína Ligasas/genética , Arabidopsis/crecimiento & desarrollo , Sequías , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Reguladores del Crecimiento de las Plantas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Complejo de la Endopetidasa Proteasomal/genética , Proteolisis , Transducción de Señal/genética , Temperatura , Ubiquitinación/genética
9.
PLoS One ; 15(6): e0234435, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32574221

RESUMEN

This study was designed to investigate the antioxidant properties of the extracts and subfractions of various polarities from Clerodendrum cyrtophyllum Turcz leaves and the related phenolic compound profiles. The ethyl acetate fraction (EAF) showed the most potent radical-scavenging activity for DPPH radicals, ABTS radicals, and superoxide anion (O2·-) radicals as well as the highest reducing power of the fractions tested; the n-butyl alcohol fraction (BAF) was the most effective in scavenging hydroxyl radical (OH·), and the dichloromethane fraction (DMF) exhibited the highest ferrous ion chelating activity. Twelve phenolic components were identified from the EAF of C. cyrtophyllum. Additionally, acteoside (1) was found to be a major component (0.803 g, 0.54%) and show DPPH and ABTS radical scavenging activities with IC50 values of 79.65±3.4 and 23.00±1.5 µg/ml, indicating it is principally responsible for the significant total antioxidant effect of C. cyrtophyllum. Our work offers a theoretical basis for further utilization of C. cyrtophyllum as a potential source of natural, green antioxidants derived from plants.


Asunto(s)
Antioxidantes/farmacología , Clerodendrum/química , Glucósidos/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología , Antioxidantes/análisis , Antioxidantes/aislamiento & purificación , Glucósidos/análisis , Glucósidos/aislamiento & purificación , Radical Hidroxilo/metabolismo , Fenoles/análisis , Fenoles/aislamiento & purificación , Extractos Vegetales/análisis , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Superóxidos/metabolismo
10.
Neural Netw ; 128: 172-187, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32447262

RESUMEN

Accurately segmenting contrast-filled vessels from X-ray coronary angiography (XCA) image sequence is an essential step for the diagnosis and therapy of coronary artery disease. However, developing automatic vessel segmentation is particularly challenging due to the overlapping structures, low contrast and the presence of complex and dynamic background artifacts in XCA images. This paper develops a novel encoder-decoder deep network architecture which exploits the several contextual frames of 2D+t sequential images in a sliding window centered at current frame to segment 2D vessel masks from the current frame. The architecture is equipped with temporal-spatial feature extraction in encoder stage, feature fusion in skip connection layers and channel attention mechanism in decoder stage. In the encoder stage, a series of 3D convolutional layers are employed to hierarchically extract temporal-spatial features. Skip connection layers subsequently fuse the temporal-spatial feature maps and deliver them to the corresponding decoder stages. To efficiently discriminate vessel features from the complex and noisy backgrounds in the XCA images, the decoder stage effectively utilizes channel attention blocks to refine the intermediate feature maps from skip connection layers for subsequently decoding the refined features in 2D ways to produce the segmented vessel masks. Furthermore, Dice loss function is implemented to train the proposed deep network in order to tackle the class imbalance problem in the XCA data due to the wide distribution of complex background artifacts. Extensive experiments by comparing our method with other state-of-the-art algorithms demonstrate the proposed method's superior performance over other methods in terms of the quantitative metrics and visual validation. To facilitate the reproductive research in XCA community, we publicly release our dataset and source codes at https://github.com/Binjie-Qin/SVS-net.


Asunto(s)
Atención , Angiografía Coronaria/métodos , Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Artefactos , Angiografía Coronaria/tendencias , Aprendizaje Profundo/tendencias , Humanos , Procesamiento de Imagen Asistido por Computador/tendencias
11.
Pattern Recognit ; 87: 38-54, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31447490

RESUMEN

This paper proposes an effective method for accurately recovering vessel structures and intensity information from the X-ray coronary angiography (XCA) images of moving organs or tissues. Specifically, a global logarithm transformation of XCA images is implemented to fit the X-ray attenuation sum model of vessel/background layers into a low-rank, sparse decomposition model for vessel/background separation. The contrast-filled vessel structures are extracted by distinguishing the vessels from the low-rank backgrounds by using a robust principal component analysis and by constructing a vessel mask via Radon-like feature filtering plus spatially adaptive thresholding. Subsequently, the low-rankness and inter-frame spatio-temporal connectivity in the complex and noisy backgrounds are used to recover the vessel-masked background regions using tensor completion of all other background regions, while the twist tensor nuclear norm is minimized to complete the background layers. Finally, the method is able to accurately extract vessels' intensities from the noisy XCA data by subtracting the completed background layers from the overall XCA images. We evaluated the vessel visibility of resulting images on real X-ray angiography data and evaluated the accuracy of vessel intensity recovery on synthetic data. Experiment results show the superiority of the proposed method over the state-of-the-art methods.

12.
Int J Mol Sci ; 20(11)2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31159261

RESUMEN

Fructans play vital roles in abiotic stress tolerance in plants. In this study, we isolated the sucrose:6-fructosyltransferase gene, which is involved in the synthesis of fructans, from Leymus mollis by rapid amplification of cDNA ends. The Lm-6-SFT gene was introduced into Arabidopsis thaliana cv. Columbia by Agrobacterium-mediated transformation. The transgenic plants were evaluated under salt stress conditions. The results showed that the expression of Lm-6-SFT was significantly induced by light, abscisic acid (ABA), salicylic acid (SA), and salt treatment in L. mollis plants. Overexpression of Lm-6-SFT in Arabidopsis promoted seed germination and primary root growth during the early vegetative growth stage under salt stress. We also found that the transgenic plants expressing Lm-6-SFT had increased proline and fructan levels. ß-Glucuronidase staining and promoter analysis indicated that the promoter of Lm-6-SFT was regulated by light, ABA, and salt stress. Quantitative PCR suggested that overexpression of Lm-6-SFT could improve salt tolerance by interacting with the expression of some salt stress tolerance genes. Thus, we demonstrated that the Lm-6-SFT gene is a candidate gene that potentially confers salt stress tolerance to plants. Our study will aid the elucidation of the regulatory mechanism of 6-SFT genes in herb plants.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , Fructanos/metabolismo , Hexosiltransferasas/genética , Poaceae/genética , Tolerancia a la Sal/genética , Regulación de la Expresión Génica de las Plantas , Hexosiltransferasas/metabolismo , Sistemas de Lectura Abierta , Fenotipo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Estrés Fisiológico/genética
13.
Phys Med Biol ; 63(17): 17LT01, 2018 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-30088812

RESUMEN

This letter proposes to extract contrast-filled vessels from overlapped noisy complex backgrounds in an x-ray coronary angiogram image sequence using low-rank and sparse decomposition. A refined vessel segmentation is finally achieved by implementing a radon-like feature filtering plus local-to-global adaptive thresholding to tackle the spatially varying noisy residuals in the extracted vessels. Based on real and synthetic XCA data, the experiment results demonstrate the superiority of the proposed method over the state-of-the-art methods.


Asunto(s)
Algoritmos , Vasos Sanguíneos/diagnóstico por imagen , Angiografía Coronaria/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Humanos
14.
Plant Cell ; 26(3): 1105-17, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24668749

RESUMEN

The apical hook is an essential structure that enables epigeal plants to protrude through the soil. Arabidopsis thaliana HOOKLESS1 (HLS1) is reported to be a key regulator of hook development and a direct target gene of the ethylene (ET)-activated transcription factors ETHYLENE INSENSITIVE3 (EIN3) and its close homolog EIN3-Like1. Previous research has shown that the phytohormones jasmonate (JA) and ET antagonistically regulate apical hook development, although the underlying molecular mechanism is largely unknown. Here, we report that JA represses hook formation by reducing HLS1 expression. Our results further reveal that the JA-activated transcription factor MYC2 represses EIN3 function to reduce HLS1 expression through at least the following two layers of regulation: (1) MYC2 binds to the promoter of an F-box gene, EIN3 BINDING F-BOX PROTEIN1, to induce its expression and thus promote EIN3 degradation; and (2) MYC2 physically interacts with EIN3 and inhibits its DNA binding activity. Collectively, our findings shed light on the molecular mechanism underlying the antagonism between JA and ET during apical hook development and provide insight into the coaction of multiple phytohormones in the regulation of plant growth and development.


Asunto(s)
Proteínas de Arabidopsis/antagonistas & inhibidores , Proteínas de Arabidopsis/fisiología , Arabidopsis/crecimiento & desarrollo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/fisiología , Ciclopentanos/metabolismo , Etilenos/antagonistas & inhibidores , Proteínas Nucleares/antagonistas & inhibidores , Oxilipinas/metabolismo , Factores de Transcripción/antagonistas & inhibidores , Proteínas de Arabidopsis/metabolismo , Secuencia de Bases , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Proteínas de Unión al ADN , Regulación hacia Abajo , Ensayo de Cambio de Movilidad Electroforética , Proteínas Nucleares/metabolismo , Sondas de Oligonucleótidos , Unión Proteica , Proteolisis , Factores de Transcripción/metabolismo
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