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1.
Plant Physiol ; 194(3): 1577-1592, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38006319

RESUMEN

The improvement of fruit quality, in particular sugar content, has been a major goal of plant breeding programmes for many years. Here, 2 varieties of the Ussurian pear (Pyrus ussuriensis), Nanguo, and its high-sucrose accumulation bud sport, Nanhong, were used to study the molecular mechanisms regulating sucrose transport in fruits. Comparative transcriptome analysis showed that in Nanhong fruit, an MYB transcription factor, PuMYB12, and a sucrose transporter protein, PuSUT4-like, were expressed at higher levels, while a paclobutrazol resistance transcription factor, PuPRE6, and a histone deacetylase (HDAC), PuHDAC9-like, were expressed at lower levels in Nanguo fruit. PuSUT4-like silencing and overexpression experiments in Nanguo pear showed that PuSUT4-like is essential for sucrose transportation. PuPRE6 and PuMYB12 act as antagonistic complexes to regulate PuSUT4-like transcription and sucrose accumulation. The histone deacetylation levels of the PuMYB12 and PuSUT4-like promoters were higher in Nanguo fruit than in Nanhong fruit, and Y1H assays showed that HDAC PuHDAC9-like bound directly to the promoters of PuMYB12 and PuSUT4-like. Our results uncovered transcription regulation and epigenetic mechanisms underlying sucrose accumulation in pears.


Asunto(s)
Pyrus , Factores de Transcripción , Pyrus/genética , Fitomejoramiento , Histona Desacetilasas/genética , Sacarosa
2.
Molecules ; 29(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38611778

RESUMEN

Polymer research is currently focused on sustainable and degradable polymers which are cheap, easy to synthesize, and environmentally friendly. Silicon-based polymers are thermally stable and can be utilized in various applications, such as columns and coatings. Poly(silyl ether)s (PSEs) are an interesting class of silicon-based polymers that are easily hydrolyzed in either acidic or basic conditions due to the presence of the silyl ether Si-O-C bond. Synthetically, these polymers can be formed in several different ways, and the most effective and environmentally friendly synthesis is dehydrogenative cross coupling, where the byproduct is H2 gas. These polymers have a lot of promise in the polymeric materials field due to their sustainability, thermal stability, hydrolytic degradability, and ease of synthesis, with nontoxic byproducts. In this review, we will summarize the synthetic approaches for the PSEs in the recent literature, followed by the properties and applications of these materials. A conclusion and perspective will be provided at the end.

3.
J Gastroenterol Hepatol ; 37(3): 531-541, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34931384

RESUMEN

BACKGROUND AND AIM: Anti-tumor necrosis factor-α (anti-TNF-α) agents have been used for inflammatory bowel disease; however, it has up to 30% nonresponse rate. Identifying molecular pathways and finding reliable diagnostic biomarkers for patient response to anti-TNF-α treatment are needed. METHODS: Publicly available transcriptomic data from inflammatory bowel disease patients receiving anti-TNF-α therapy were systemically collected and integrated. In silico flow cytometry approaches and Metascape were applied to evaluate immune cell populations and to perform gene enrichment analysis, respectively. Genes identified within enrichment pathways validated in neutrophils were tracked in an anti-TNF-α-treated animal model (with lipopolysaccharide-induced inflammation). The receiver operating characteristic curve was applied to all genes to identify the best prediction biomarkers. RESULTS: A total of 449 samples were retrieved from control, baseline, and after primary anti-TNF-α therapy or placebo. No statistically significant differences were observed between anti-TNF-α treatment responders and nonresponders at baseline in immune microenvironment scores. Neutrophil, endothelial cell, and B-cell populations were higher in baseline nonresponders, and chemotaxis pathways may contribute to the treatment resistance. Genes related to chemotaxis pathways were significantly upregulated in lipopolysaccharide-induced neutrophils, but no statistically significant changes were observed in neutrophils treated with anti-TNF-α. Interleukin 13 receptor subunit alpha 2 (IL13RA2) is the best predictor (receiver operating characteristic curve: 80.7%, 95% confidence interval: 73.8-87.5%), with a sensitivity of 68.13% and specificity of 84.93%, and significantly higher in nonresponders compared with responders (P < 0.0001). CONCLUSIONS: Hyperactive neutrophil chemotaxis influences responses to anti-TNF-α treatment, and IL13RA2 is a potential biomarker to predict anti-TNF-α treatment response.


Asunto(s)
Quimiotaxis , Enfermedades Inflamatorias del Intestino , Neutrófilos , Inhibidores del Factor de Necrosis Tumoral , Animales , Quimiotaxis/fisiología , Resistencia a Medicamentos , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Neutrófilos/fisiología , Inhibidores del Factor de Necrosis Tumoral/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/efectos de los fármacos
4.
J Biomed Inform ; 106: 103435, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32360988

RESUMEN

The task of electronic medical record named entity recognition (NER) refers to automatically identify all kinds of named entities in the medical record text. Chinese clinical NER remains a major challenge. One of the main reasons is that Chinese word segmentation will lead to the wrong downstream works. Besides, existing methods only use the information of the general field, not consider the knowledge from field of medicine. To address these issues, we propose a dynamic embedding method based on dynamic attention which combines features of both character and word in embedding layer. Domain knowledge is provided by word vector trained by domain dataset. In addition, spatial attention is added to enable the model to obtain more and more effective context encoding information. Finally, we conduct extensive experiments to demonstrate the effectiveness of our proposed algorithm. Experiments on CCKS2017 and Common dataset shows that the proposed method outperforms the baseline.


Asunto(s)
Registros Electrónicos de Salud , Envío de Mensajes de Texto , Algoritmos , Atención , China
5.
Molecules ; 25(18)2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32899682

RESUMEN

Ring opening copolymerization (ROCOP) of epoxides and cyclic anhydrides has become an attractive approach for the synthesis of biodegradable polyesters with various compositions. Encouraged by the efficiency and versatility of a series of amido-oxazolinate zinc complexes, in this study they were shown to be active catalysts for the synthesis of unsaturated polyesters via ROCOP of maleic anhydride and various epoxides. The relative activity of epoxides in these reactions was observed to be styrene oxide > cyclohexene oxide > phenyl glycidyl ether, which could be correlated with the electronic and steric features of the substrate. To provide more structural possibilities for the polyesters, the difference in epoxide reactivity was exploited in an attempt to prepare block terpolymers from one anhydride and two epoxides. Terpolymerization was carried out in one or two steps in a single pot. The thermal characterization by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques suggested that the resulting materials were mostly random terpolymers.


Asunto(s)
Amidas/química , Compuestos Epoxi/química , Anhídridos Maleicos/química , Oxazoles/química , Polimerizacion , Zinc/química , Espectroscopía de Resonancia Magnética con Carbono-13 , Ciclohexenos/química , Espectroscopía de Protones por Resonancia Magnética , Temperatura , Termogravimetría
6.
J Sci Food Agric ; 100(13): 4766-4775, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32458515

RESUMEN

BACKGROUND: Peel color is an economically relevant trait that influences the appearance and quality of red pear, whose red color is due to anthocyanin accumulation. Prohydrojasmon (PDJ), which has similar effects to endogenous jasmonates, was developed as a commercial bioregulator, particularly to improve fruits coloring. However, little information is available about the effect of PDJ on pears. This study investigated the effects of preharvest PDJ treatments on color development, phenolic compounds accumulation, and related gene expression in the red pear cultivar 'Nanhong'. The treatments were performed during the pre-color-change period by spraying 50 or 100 mg L-1 of PDJ on fruits. RESULTS: Preharvest PDJ treatments had a significant effect on color development, without affecting other quality parameters such as total soluble solids and fruit acidity. Liquid chromatography-mass spectrometry analysis showed that concentrations of anthocyanins and flavonols were enhanced in the peel after PDJ treatments, particularly when a concentration of 100 mg L-1 was used, whereas those of hydroxycinnamates and flavanols were decreased. After PDJ application, the transcription levels of anthocyanin biosynthesis genes PAL, CHS, CHI, ANS, F3H, and UFGT were enhanced, especially under the higher PDJ concentration tested. In addition, anthocyanin accumulation in the peels of PDJ-treated fruits was found to be positively correlated with the upregulation of the regulatory gene MYB114. CONCLUSION: Preharvest treatments with PDJ could be a useful tool to improve fruits coloring and increase phenolic content in pear. These findings also improve our understanding of the molecular mechanisms associated with PDJ-regulated anthocyanin accumulation in pear fruits.


Asunto(s)
Frutas/crecimiento & desarrollo , Fenoles/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Plantas/genética , Pyrus/efectos de los fármacos , Antocianinas/biosíntesis , Color , Frutas/química , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Fenoles/química , Proteínas de Plantas/metabolismo , Pyrus/genética , Pyrus/crecimiento & desarrollo , Pyrus/metabolismo
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 809-13, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26117902

RESUMEN

As a rapid, in-situ analysis method, Field portable X-ray fluorescence spectrometry (FP-XRF) can be widely applied in soil heavy metals analysis field. Whereas, some factors may affect FP-XRF performance and restrict the application. Studies have proved that FP-XRF has poorer performance when the concentration of target element is low, and soil moisture and particle size will affect FP-XRF performance. But few studies have been conducted in depth. This study took an example of Ni, demonstrated the relationship between Ni concentration and FP-XRF performance on accuracy and precision, and gave a critical value. Effects of soil moisture and particle size on accuracy and precision also had been compared. Results show that, FP-XRF performance is related to Ni concentration and the critical value is 400 mg x kg(-1). Relative standard deviation (RSD) and relative uncertainty decrease while the Ni concentration is below 400 mg x kg(-1), hence FP-XRF performance improves with increasing Ni concentration in this range; RSD and relative uncertainty change little while the Ni concentration is above 400 mg x kg(-1), hence FP-XRF performance does not have correlation with Ni concentration any more. For in-situ analysis, the relative uncertainty contributed by soil moisture is 3.77%, and the relative certainty contributed by particle size is 0.56%. Effect of soil moisture is evidently more serious than particle size both on accuracy and precision.

8.
Sci Rep ; 14(1): 8012, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580704

RESUMEN

The objective of human pose estimation (HPE) derived from deep learning aims to accurately estimate and predict the human body posture in images or videos via the utilization of deep neural networks. However, the accuracy of real-time HPE tasks is still to be improved due to factors such as partial occlusion of body parts and limited receptive field of the model. To alleviate the accuracy loss caused by these issues, this paper proposes a real-time HPE model called CCAM - Person based on the YOLOv8 framework. Specifically, we have improved the backbone and neck of the YOLOv8x-pose real-time HPE model to alleviate the feature loss and receptive field constraints. Secondly, we introduce the context coordinate attention module (CCAM) to augment the model's focus on salient features, reduce background noise interference, alleviate key point regression failure caused by limb occlusion, and improve the accuracy of pose estimation. Our approach attains competitive results on multiple metrics of two open-source datasets, MS COCO 2017 and CrowdPose. Compared with the baseline model YOLOv8x-pose, CCAM-Person improves the average precision by 2.8% and 3.5% on the two datasets, respectively.


Asunto(s)
Benchmarking , Extremidades , Humanos , Redes Neurales de la Computación , Postura , Grabación de Cinta de Video
9.
Pest Manag Sci ; 80(7): 3590-3602, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38451056

RESUMEN

BACKGROUND: Nanguo pear is a distinctive pear variety in northeast China, grown mainly in mountainous areas. Due to terrain limitations, ground-based pesticide application equipment is difficult to use. This limitation could be overcome by using unmanned aerial vehicles (UAVs) for pesticide application in Nanguo pear orchards. This study evaluated the spraying performance of two UAVs in the Nanguo pear orchards and compared them with a manually used backpack electric sprayer (BES). The study also analyzed the effect of canopy size on droplet deposition and ground loss, and evaluated two sampling methods, leaf sampling and telescopic rod sampling. RESULTS: Compared to BESs, droplet deposition is lower for UAVs, but the actual pesticide active ingredient deposition is not necessarily lower given the solution concentration. The droplet deposition varies among different UAVs due to structural differences. Under the same UAV operating parameters, droplet deposition on trees with smaller canopy sizes is typically greater than that on trees with larger canopy sizes, and the ground loss was also more severe. Although telescopic rod sampling is a quick and convenient method, it can only reflect the trend of droplet deposition, and the data error is greater compared with leaf sampling. CONCLUSION: UAVs can achieve better droplet deposition in mountainous Nanguo pear orchards and does almost no harm to the operators compared with the BES. However, canopy size needs to be considered to adjust the application volume rate. Telescopic rods can be used for qualitative analyses, but are not recommended for quantitative analyses. © 2024 Society of Chemical Industry.


Asunto(s)
Pyrus , Pyrus/química , Dispositivos Aéreos No Tripulados , China , Hojas de la Planta/química
10.
J Thromb Haemost ; 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39357567

RESUMEN

BACKGROUND: Despite appropriate treatment, up to 50% of patients with proximal deep vein thrombosis (DVT) will develop the post-thrombotic syndrome (PTS). Once PTS occurs, there is no specific treatment, and some patients constantly suffer from intolerable symptoms. How to prevent PTS is important. OBJECTIVES: Characterize vein wall remodeling after thrombus and investigate the effects of antiproliferative agent on post-thrombotic vein wall remodeling in murine and human subjects. METHODS: Features of post-thrombotic vein wall remodeling in murine and human subjects were characterized using imaging and histological examinations. Paclitaxel-loaded hydrogels were used to assess the effects of antiproliferative agent on the remodeling in murine model. Based on the above results, a pilot study was conducted to assess the effects of paclitaxel-coated balloon dilation in severe PTS patients suffering from intolerable symptoms. The control cohort was obtained by 1:1 propensity score matching from a prospective database. RESULTS: Structural and functional alterations in post-thrombotic vein wall were verified by imaging and histological examinations, and predominant active α-SMA+ cells and FSP-1+ cells proliferation was observed. In the murine model, the application of paclitaxel-loaded hydrogels inhibited the remodeling. In the pilot clinical study, patients receiving DCB demonstrated benefits in Villalta scores and VCSS scores compared with those not receiving DCB, and no severe adverse events reported except for thrombosis recurrence. CONCLUSION: Cell proliferation plays an important role in post-thrombotic vein wall remodeling. Inhibition of cell proliferation inhibits the remodeling in murine model, and may reduce signs and symptoms in severe PTS patients.

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