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1.
Plant Physiol Biochem ; 215: 109036, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39128404

RESUMEN

In plants, microRNAs (miRNAs) are a class of important small RNAs involved in their growth and development, and play a very significant role in regulating their tissue coloring. In this paper, the mechanisms on miRNA regulation of plant coloring are mainly reviewed from three aspects: macroscopic physiological and molecular foundations related to tissue coloring, miRNA biosynthesis and function, and specific analysis of miRNA regulation studies on leaf color, flower color, fruit color, and other tissue color formation in plants. Furthermore, we also systematically summarize the miRNA regulatory mechanisms identified on pigments biosynthesis and color formation in plants, and the regulatory mechanisms of these miRNAs mentioned on the existing researches can be divided into four main categories: directly targeting the related transcription factors, directly targeting the related structural genes, directly targeting the related long noncoding RNAs (LncRNAs) and miRNA-mediated production of trans-acting small interfering RNAs (ta-siRNAs). Together, these research results aim to provide a theoretical reference for the in-depth study of plant coloring mechanism and molecular breeding study of related plants in the future.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , MicroARNs , ARN de Planta , MicroARNs/genética , MicroARNs/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , Plantas/genética , Plantas/metabolismo , Pigmentación/genética , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Flores/genética
2.
Biomed Chromatogr ; 38(9): e5935, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38924114

RESUMEN

Dissipative behavior and final residue levels of difenoconazole, prochloraz, propiconazole, and pyraclostrobin in figs were investigated using field trials and laboratory assays. A three-factor, three-level orthogonal test was designed to optimize the pretreatment conditions of the method. A method was established using high-performance liquid chromatography tandem mass spectrometry for the determination of difenoconazole, prochloraz, propiconazole, and pyraclostrobin residues in figs. The limit of quantification for all four targets in figs was 0.002 mg/kg. Difenoconazole, prochloraz, propiconazole, and pyraclostrobin are readily digestible pesticides in figs with half-lives of 6.4, 6.2, 4.8, and 7.9 days, respectively. Residues of difenoconazole, prochloraz, propiconazole, and pyraclostrobin in figs were below the European Union established residue levels of 0.1, 0.03, 0.01, and 0.02 mg/kg, respectively, at day 7 after application. Pyraclostrobin, propiconazole, difenoconazole, and prochloraz were applied twice at doses of 75, 125, 150, and 200 mg a.i./kg at 7-day intervals, and the residues of the four fungicides in figs were acceptable 7 days after the last application. Therefore, the safety interval can be set at 7 days for 70% difenoconazole-prochloraz wettable powder and 40% pyraclostrobin-propiconazole aqueous emulsion according to the protocol.


Asunto(s)
Ficus , Fungicidas Industriales , Residuos de Plaguicidas , Espectrometría de Masas en Tándem , Espectrometría de Masas en Tándem/métodos , Fungicidas Industriales/análisis , Residuos de Plaguicidas/análisis , Ficus/química , Reproducibilidad de los Resultados , Límite de Detección , Cromatografía Líquida de Alta Presión/métodos , Modelos Lineales , Dioxolanos/análisis , Cromatografía Liquida/métodos , Triazoles/análisis , Triazoles/química , Estrobilurinas
3.
BMC Genomics ; 25(1): 114, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273225

RESUMEN

BACKGROUND: Theaceae, comprising 300 + species, holds significance in biodiversity, economics, and culture, notably including the globally consumed tea plant. Stewartia gemmata, a species of the earliest diverging tribe Stewartieae, is critical to offer insights into Theaceae's origin and evolutionary history. RESULT: We sequenced the complete organelle genomes of Stewartia gemmata using short/long reads sequencing technologies. The chloroplast genome (158,406 bp) exhibited a quadripartite structure including the large single-copy region (LSC), a small single-copy region (SSC), and a pair of inverted repeat regions (IRs); 114 genes encoded 80 proteins, 30 tRNAs, and four rRNAs. The mitochondrial genome (681,203 bp) exhibited alternative conformations alongside a monocyclic structure: 61 genes encoding 38 proteins, 20 tRNAs, three rRNAs, and RNA editing-impacting genes, including ATP6, RPL16, COX2, NAD4L, NAD5, NAD7, and RPS1. Comparative analyses revealed frequent recombination events and apparent rRNA gene gains and losses in the mitochondrial genome of Theaceae. In organelle genomes, the protein-coding genes exhibited a strong A/U bias at codon endings; ENC-GC3 analysis implies selection-driven codon bias. Transposable elements might facilitate interorganelle sequence transfer. Phylogenetic analysis confirmed Stewartieae's early divergence within Theaceae, shedding light on organelle genome characteristics and evolution in Theaceae. CONCLUSIONS: We studied the detailed characterization of organelle genomes, including genome structure, composition, and repeated sequences, along with the identification of lateral gene transfer (LGT) events and complexities. The discovery of a large number of repetitive sequences and simple sequence repeats (SSRs) has led to new insights into molecular phylogenetic markers. Decoding the Stewartia gemmata organellar genome provides valuable genomic resources for further studies in tea plant phylogenomics and evolutionary biology.


Asunto(s)
Genoma del Cloroplasto , Theaceae , Filogenia , Theaceae/genética , Genómica , Codón/genética , Cloroplastos/genética , ARN de Transferencia/genética ,
4.
Adv Mater ; 36(16): e2313155, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38228320

RESUMEN

The electrosynthesis of nitrate catalyzed by electrochemical nitrogen oxidation reaction (NOR) is considered as an alternative and sustainable approach to the conventional industrial manufacture, but optimizing the electrocatalytic NOR performance and fabricating the efficient NOR electrocatalysts at the design level still encounter great challenges. Herein, unique Pd2+- and S2--doped TiO2 (Pb/S-TiO2) nanoparticles are successfully in situ grown on the surface of 2-methylimidazolium-functionalized polypyrrole/graphene oxide (2-MeIm/PPy/GO), which present the typical hierarchical micro-nanostructures, resulting in the excellent electrocatalytic NOR performance with the highest NO3 - yield of 72.69 µg h-1 mg-1 act. and the maximum Faraday efficiency of 8.92% at 2.04 V (vs reversible hydrogen electrode) due to the synergistic effect of each component. Due to the doping effect, the appropriate oxygen evolution reaction (OER) activity is achieved by Ti-site, where OER principally occurs, providing *O during the non-electrochemical step of NOR, while the electrocatalytic NOR process as the electrochemical conversion of inert N2 to active *NO intermediates mainly occurs at the Pd-site. Especially, the sulfate radicals in situ formed on Pb/S-TiO2@2-MeIm/PPy/GO further promote nitrogen adsorption and decrease the reaction energy barrier, resulting in the acceleration of NOR. It provides theoretical and practical experience for the design and preparation of NOR electrocatalysts.

5.
Biomimetics (Basel) ; 8(5)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37754149

RESUMEN

Soft fingertips have distinct intrinsic features that allow robotic hands to offer adjustable and manageable stiffness for grasping. The stability of the grasp is determined by the contact stiffness between the soft fingertip and the object. Within this work, we proposed a line vector representation method based on the Winkler Model and investigated the contact stiffness between soft fingertips and objects to achieve control over the gripping force and fingertip displacement of the gripper without the need for sensors integrated in the fingertip. First, we derived the stiffness matrix of the soft fingertip, analyzed the contact stiffness, and constructed the global stiffness matrix; then, we established the grasp stiffness matrix based on the contact stiffness model, allowing for the analysis and evaluation of the soft fingertip's manipulating process. Finally, our experiment demonstrated that the variation in object orientation caused by external forces can indicate the contact force status between the fingertip and the object. This contact force status is determined by the contact stiffness. The position error between the theoretical work and tested data was less than 9%, and the angle error was less than 5.58%. The comparison between the theoretical contact stiffness and the experimental results at the interface indicate that the present model for the contact stiffness is appropriate and the theoretical contact stiffness is consistent with the experiment data.

6.
Front Plant Sci ; 14: 1114284, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36890899

RESUMEN

As one of the world's top three popular non-alcoholic beverages, tea is economically and culturally valuable. Xinyang Maojian, this elegant green tea, is one of the top ten famous tea in China and has gained prominence for thousands of years. However, the cultivation history of Xinyang Maojian tea population and selection signals of differentiation from the other major variety Camellia sinensis var. assamica (CSA) remain unclear. We newly generated 94 Camellia sinensis (C. sinensis) transcriptomes including 59 samples in the Xinyang area and 35 samples collected from 13 other major tea planting provinces in China. Comparing the very low resolution of phylogeny inferred from 1785 low-copy nuclear genes with 94 C. sinensis samples, we successfully resolved the phylogeny of C. sinensis samples by 99,115 high-quality SNPs from the coding region. The sources of tea planted in the Xinyang area were extensive and complex. Specifically, Shihe District and Gushi County were the two earliest tea planting areas in Xinyang, reflecting a long history of tea planting. Furthermore, we identified numerous selection sweeps during the differentiation of CSA and CSS and these positive selection genes are involved in many aspects such as regulation of secondary metabolites synthesis, amino acid metabolism, photosynthesis, etc. Numerous specific selective sweeps of modern cultivars were annotated with functions in various different aspects, indicating the CSS and CSA populations possibly underwent independent specific domestication processes. Our study indicated that transcriptome-based SNP-calling is an efficient and cost-effective method in untangling intraspecific phylogenetic relationships. This study provides a significant understanding of the cultivation history of the famous Chinese tea Xinyang Maojian and unravels the genetic basis of physiological and ecological differences between the two major tea subspecies.

7.
Arch Med Sci ; 19(1): 16-24, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36817680

RESUMEN

Introduction: There is increased interest in the use of positron emission tomography (PET) in psoriatic patients. We used PET induced with tracer fluorine-18 (18F) fluorodeoxyglucose (FDG) to study the association between the process of early-atherogenesis (eAg) and aortitis by quantifying enhanced aortic vascular inflammation along with calculation of total coronary plaque load (TCPL) and non-calcified atherosclerotic plaque load (NcAPL). In order to study the utility of aortitis in capturing eAg, we also assessed luminal stenosis atherosclerosis (LSA) and high-risk coronary plaques (HrCP). Material and methods: The study was conducted at our hospital between 1 April 2014 and 31 December 2017, and the analysis was done in July 2018. We recruited 180 consecutive psoriatic patients and subjected them to 18F-FDG PET. However, in order to characterise eAg, 160 out of 180 patients were also subjected to coronary angiographic computed tomographic studies (CACTS). Results: Among 180 psoriatic patients (76 women, 42%) (mean [SD] age, 51.1 [13.2] years), greater prevalence values of LSA (odd ratio [OR], 3.71; 95% confidence interval [CI], 1.84-7.89; p = 0.001) and HrCP (OR, 3.11; 95% CI: 1.54-6.51; p = 0.003) along with enhanced TCPL (standardised ß = 0.44; p < 0.001) were observed in patients with enhanced aortitis. However, the association between aortitis and HrCP was controlled by low-attenuation plaque (LAP), while the same between aortitis and TCPL was controlled by NcAPL (ß = 0.45; p < 0.001). Conclusions: Association between aortitis and broad coronary angiographic indices was achieved and hence predicted the possibility of a surrogate role of aortitis in eAg.

8.
Acta Radiol Open ; 12(1): 20584601231152640, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36699098

RESUMEN

Horseshoe lung (HL) is an infrequent congenital lung anomaly. Its main feature is that the lower lungs on both sides extend behind the pericardium and fuse across the midline, usually accompanied by pulmonary dysplasia. It is reported that 80% of HL is relevant to the abnormal return of some pulmonary veins from the right lung to the inferior vena cava or right atrium (scimitar syndrome). Most patients are within 5 years old, most commonly within 1 year old, but HL may also have no apparent clinical symptoms or mild symptoms. This case is a 36-years-old adult female who developed left chest pain more than a month ago and continued to worsen for 10 days. The patient also had repeated pulmonary infection with cough and expectoration.

9.
Insights Imaging ; 13(1): 184, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36471022

RESUMEN

OBJECTIVE: This study aimed to develop a deep learning (DL) model to improve the diagnostic performance of EIC and ASPECTS in acute ischemic stroke (AIS). METHODS: Acute ischemic stroke patients were retrospectively enrolled from 5 hospitals. We proposed a deep learning model to simultaneously segment the infarct and estimate ASPECTS automatically using baseline CT. The model performance of segmentation and ASPECTS scoring was evaluated using dice similarity coefficient (DSC) and ROC, respectively. Four raters participated in the multi-reader and multicenter (MRMC) experiment to fulfill the region-based ASPECTS reading under the assistance of the model or not. At last, sensitivity, specificity, interpretation time and interrater agreement were used to evaluate the raters' reading performance. RESULTS: In total, 1391 patients were enrolled for model development and 85 patients for external validation with onset to CT scanning time of 176.4 ± 93.6 min and NIHSS of 5 (IQR 2-10). The model achieved a DSC of 0.600 and 0.762 and an AUC of 0.876 (CI 0.846-0.907) and 0.729 (CI 0.679-0.779), in the internal and external validation set, respectively. The assistance of the DL model improved the raters' average sensitivities and specificities from 0.254 (CI 0.22-0.26) and 0.896 (CI 0.884-0.907), to 0.333 (CI 0.301-0.345) and 0.915 (CI 0.904-0.926), respectively. The average interpretation time of the raters was reduced from 219.0 to 175.7 s (p = 0.035). Meanwhile, the interrater agreement increased from 0.741 to 0.980. CONCLUSIONS: With the assistance of our proposed DL model, radiologists got better performance in the detection of AIS lesions on NCCT.

10.
J Colloid Interface Sci ; 618: 322-332, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35349802

RESUMEN

Carbonaceous materials are extensively utilized to optimize the electrochemical performance of the transition metal oxides as anode for lithium-ion batteries. However, the in-depth mechanism of the synergistic effect and the interfacial interaction between transition metal oxides and conductive carbon material has not been elucidated clearly. Herein, by using the oxidized multi-walled carbon nanotubes (oMWCNTs), an advanced MnO2/(Co, Mn)(Co, Mn)2O4/oMWCNTs (MO/CMO/oMWCNTs) nanocomposite with abundant metal-oxygen-carbon (Me-OC) bonds as linkage bridge is fabricated for the first time. The strong covalent bonds interactions can simultaneously enhance the intrinsic sluggish kinetics and structural stability of MO/CMO/oMWCNTs nanocomposite. Meanwhile, the mixed transition metal oxides featuring mix valence state can significantly promote the electrode material activity. Consequently, the newly prepared MO/CMO/oMWCNTs electrode displays superior long-term durability with the capacity of 897 mAh g-1 over 1000 cycles at 2 A g-1 and ultrafast charging/discharging capability of 673 mAh g-1 at 5 A g-1. Detailed electrochemical kinetic analysis reveals that over 70% of the energy storage of MO/CMO/oMWCNTs electrode is dominated by the pseudocapacitive behavior. This work demonstrates an easily scalable approach for constructing high-performance transition metal oxides/carbon electrode materials through interfacial regulation.

11.
Anal Bioanal Chem ; 414(12): 3593-3603, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35217877

RESUMEN

A simple and sensitive electrochemical cholesterol biosensor was fabricated based on ceramic-coated liposome (cerasome) and graphene quantum dots (GQDs) with good conductivity. The cerasome consists of a lipid-bilayer membrane and a ceramic surface as a soft biomimetic interface, and the mild layer-by-layer self-assembled method as the immobilization strategy on the surface of the modified electrode was used, which can provide good biocompatibility to maintain the biological activity of cholesterol oxidase (ChOx). The GQDs promoted electron transport between the enzyme and the electrode more effectively. The structure of the cerasome-forming lipid was characterized by Fourier transform infrared (FT-IR). The morphology and characteristics of the cerasome and GQDs were characterized by transmission electron microscopy (TEM), zeta potential, photoluminescence spectra (PL), etc. The proposed biosensors revealed excellent catalytic performance to cholesterol with a linear concentration range of 16.0 × 10-6-6.186 × 10-3 mol/L, with a low detection limit (LOD) of 5.0 × 10-6 mol/L. The Michaelis-Menten constant (Km) of ChOx was 5.46 mmol/L, indicating that the immobilized ChOx on the PEI/GQDs/PEI/cerasome-modified electrode has a good affinity to cholesterol. Moreover, the as-fabricated electrochemical biosensor exhibited good stability, anti-interference ability, and practical application for cholesterol detection.


Asunto(s)
Técnicas Biosensibles , Grafito , Puntos Cuánticos , Biomimética , Técnicas Biosensibles/métodos , Colesterol , Colesterol Oxidasa/química , Técnicas Electroquímicas , Grafito/química , Espectroscopía Infrarroja por Transformada de Fourier
12.
J Neuroimaging ; 31(4): 733-742, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34021667

RESUMEN

BACKGROUND AND PURPOSE: To compare and characterize metabolic features of high- and low-grade glioma tumors using 68 Ga-PSMA-617 and 18 F-FDG positron emission tomography/computed tomography (PET/CT). METHODS: Thirty patients who underwent both 68 Ga-PSMA-617 and 18 F-FDG PET/CT over 2 consecutive days and then underwent surgical treatment were retrospectively identified. All tumors were diagnosed histologically. This report includes 16 high-grade glioma (HGG) and 14 low-grade glioma (LGG) tumors. Standard uptake value (SUV) and target to nontarget (T/NT) were quantitatively investigated through the entire tumor region. Statistical analyses were performed using area under the curve (AUC) and comparison of two means. RESULTS: SUVmax and SUVmean were the most effective (AUC, 0.96 and 0.94 for PSMA PET; AUC, 0.79 and 0.74 for FDG PET, respectively) for differentiating HGGs from LGGs. These methods distinguished between HGG and LGG effectively (PSMA PET: SUVmax , 5.766 ± 3.945 vs. 0.7364 ± 0.5295, p < 0.0001; SUVmean , 1.666 ± 1.680 and 0.1514 ± 0.1534, p < 0.0001, respectively) (FDG PET: SUVmax , 11.67 ± 3.639 and 9.118 ± 6.612; SUVmean , 5.648 ± 2.114 and 4.435 ± 2.872; p = 0.0083, 0.0262, respectively). The Youden index for SUVmax and SUVmean of 68 Ga-PSMA-617 and 18 F-FDG were 0.82 and 0.79 and 0.54 and 0.61, separately. T/NTmax was helpful for visual inspection of 68 Ga-PSMA-617-PET images (T/NTmax : 1.291 ± 0.9553 in grade II, 5.25 ± 2.435 in grade III, and 13.61 ± 13.84 in grade IV). T/NTmax differed significantly between LGG and HGG and between subtypes of LGG. CONCLUSION: PET/CT with 68 Ga-PSMA-617 and 18 F-FDG may help distinguish between HGG and LGG, and 68 Ga-PSMA-617 PET/CT is superior to18 F-FDG in differentiating HGG and LGG.


Asunto(s)
Glioma , Tomografía Computarizada por Tomografía de Emisión de Positrones , Dipéptidos , Fluorodesoxiglucosa F18 , Glioma/diagnóstico por imagen , Compuestos Heterocíclicos con 1 Anillo , Humanos , Antígeno Prostático Específico , Estudios Retrospectivos
13.
J Nucl Cardiol ; 28(5): 2346-2357, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-32016690

RESUMEN

BACKGROUND: MCC950 is a novel NLRP3 inflammasome inhibitor that possesses potent anti-inflammatory properties in acute myocardial infarction (AMI). However, the lack of noninvasive monitoring methods limits its potential clinical translation. Thus, we sought to investigate whether 18F-FDG PET imaging can monitor the therapeutic effects of MCC950 in an AMI murine model. METHODS: C57BL/6 mice were used to generate an AMI model. MCC950 or sterile saline was intraperitoneally administered 1 hour after surgery and then daily for 7 consecutive days. 18F-FDG PET (inflammation) imaging was used to monitor inflammatory changes on days 3 and 5. Immunohistochemistry and Western blot were used to detect inflammatory markers and to confirm the PET imaging results. 18F-FDG PET (viability) imaging was used to quantitate the viability defect expansion on days 7 and 28. Cardiac ultrasound and survival analyses were performed to evaluate the cardiac function and survival rate. Adverse remodeling was determined by Wheat Germ Agglutinin (WGA) and Masson trichrome staining. RESULTS: The FDG-PET (inflammation) imaging revealed that MCC950 treatment led to lower 18F-FDG inflammatory uptakes, at the infarct region, on days 3 and 5 when compared to the MI group. The decreased M1 macrophages and neutrophils infiltration and the remission of the NLRP3/IL-1ß pathway, confirmed the FDG-PET (inflammation) imaging results. The FDG-PET (viability) imaging revealed that MCC950 significantly decreased the expansion of the viability defect, demonstrating its myocardial preservation effects. The acute FDG-PET (inflammation) signal positively correlated with the late viability defect and with the reduction in the left ventricular ejection fraction (LVEF). Additionally, the alleviated adverse remodeling and the improved survival rate further support the anti-inflammatory efficiency of MCC950 in AMI. CONCLUSION: Using 18F-FDG PET imaging, we noninvasively demonstrated the therapeutic effects of MCC950 in AMI and showed that 18F-FDG PET imaging holds promising application potentials in MCC950's clinical translation.


Asunto(s)
Antiinflamatorios/uso terapéutico , Fluorodesoxiglucosa F18 , Furanos/uso terapéutico , Indenos/uso terapéutico , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/tratamiento farmacológico , Tomografía de Emisión de Positrones , Sulfonamidas/uso terapéutico , Animales , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Radiofármacos , Remodelación Ventricular
14.
J Int Med Res ; 48(8): 300060520939326, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32814489

RESUMEN

OBJECTIVE: To investigate the visibility of peripheral pulmonary arteries by computed tomography pulmonary angiography (CTPA) and image quality using a free-breathing combined with a high-threshold bolus triggering technique and to explore the feasibility of this technique in pulmonary embolism (PE) patients who cannot hold their breath. METHODS: Patients with suspected PE who underwent CTPA (n=240) were randomly assigned to two groups: free-breathing (n=120) or breath-holding (n=120). RESULTS: The mean scanning time or visible pulmonary artery distal branches were not different between the groups. Mean CT main pulmonary artery (MPA) values, apical segment (S1), and posterior basal segment (S10) in the free-breathing group were higher compared with the breath-holding group. The subjective image quality score in the free-breathing group was higher compared with the breath-holding group. In the free-breathing group, no respiratory artifact was observed. In the breath-holding group, obvious respiratory artifacts were caused by severe chronic obstructive pulmonary disease (COPD), dyspnea, or other diseases that preclude patients from holding their breath. CONCLUSION: The free-breathing mode CTPA combined with a high-threshold bolus triggering technique can provide high quality images with a lower incidence of respiratory and cardiac motion artifacts, which is especially valuable for patients who cannot hold their breath.


Asunto(s)
Arteria Pulmonar , Embolia Pulmonar , Angiografía , Angiografía por Tomografía Computarizada , Medios de Contraste , Humanos , Arteria Pulmonar/diagnóstico por imagen , Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X
15.
PLoS One ; 15(6): e0235073, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32584862

RESUMEN

The 'Fuji' line includes many varieties with a similar genetic background and consistent inducement factors with epigenetic occurrence, thus it may be considered an ideal candidate for epigenetic research. In this study, 91 bud mutations of 'Fuji' apple were used as the test materials. Using the genetic variation within 'Fuji' as the control, the characteristics of epigenetic variation at different levels in both varieties and mutant groups were examined. The results showed that: (1) the global genomic DNA methylation level of the 91 bud mutants of 'Fuji' ranged from 29.120%-45.084%, with an average of 35.910%. Internal cytosine methylation was the main DNA methylation pattern. Regarding the variation of methylation patterns of 'Fuji' mutants, the vast majority of loci maintained the original methylation pattern existed in 'Fuji'. CHG methylation variation was the main type of variation; (2) the variation in methylation patterns between the mutant groups was greater than that of methylation levels. Among these patterns, the variation in CHG methylation patterns (including CHG hypermethylation and CHG demethylation) was expected to be dominant. The observed variation in methylation levels was more important in the Color mutant group; however, the variation in methylation patterns was more obvious in both the early maturation and Spur mutant groups. Moreover, the range of variation in the Early-maturation group was much wider than that in the Spur mutant group; (3) epigenetic diversity and genetic diversity were both low between the mutant groups. In the 'Fuji' mutant groups, there was few correlation between genetic and epigenetic variation, and epigenetic differentiation resulted in more loci with moderate or greater differentiation; (4) the purifying selection seemed to play a major role in the differentiation of different groups of 'Fuji' mutants (65.618%), but epigenetic diversity selection still occurred at nearly 35% of loci. Sixteen epigenetic outlier loci were detected.


Asunto(s)
Metilación de ADN , ADN de Plantas , Epigénesis Genética , Sitios Genéticos , Malus , Mutación , ADN de Plantas/genética , ADN de Plantas/metabolismo , Malus/genética , Malus/metabolismo
16.
ACS Appl Mater Interfaces ; 12(22): 25189-25199, 2020 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-32372649

RESUMEN

Ultrathin nanoplates of metastable 1T-MoS2 have been successfully stabilized and uniformly distributed on the surface of n-butyl triethyl ammonium bromide functionalized polypyrrole/graphene oxide (BTAB/PPy/GO) by a very simple hydrothermal method. BTAB as a typical kind of quaternary ammonium-type ionic liquids (ILs) played a crucial role in the formation of the obtained 1T-MoS2/BTAB/PPy/GO. It was covalently linked with PPy/GO and arranged in a highly ordered order at the solid-liquid interface of PPy/GO and H2O due to Coulombic interactions and other intermolecular interactions, which would induce and stabilize ultrathin 1T-MoS2 nanoplates by morphosynthesis. The good electrocatalytic activity toward nitrogen reduction reaction (NRR) with strong durability and good stability can be achieved by 1T-MoS2/BTAB/PPy/GO due to their excellent inorganic/organic hierarchical lamellar micro-/nanostructures. Especially, after the long-term electrocatalysis for NRR at a negative potential, metastable 1T-MoS2 as the catalytic center undergoes two types of irreversible crystal phase transition, which was converted to 1T'-MoS2 and Mo2N, caused by the competitive hydrogen evolution reaction (HER) process and the electrochemical reaction between the electroactive 1T-MoS2 and N2, respectively. The new N-Mo bonding prevents Mo atoms from binding to other N atoms in N2, resulting in the deactivation of the electrocatalysts to NRR after being used for 18 h. Even so, quaternary ammonium-type ILs would induce the crystal structures of transition-metal dichalcogenides (TMDCs), which might provide a new thought for the reasonable design of electrocatalysts based on TMDCs for electrocatalysis.

17.
Stem Cell Res Ther ; 11(1): 207, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32460839

RESUMEN

The novel coronavirus disease 2019 (COVID-19) has grown to be a global public health emergency since patients were first detected in Wuhan, China. Thus far, no specific drugs or vaccines are available to cure the patients with COVID-19 infection. The immune system and inflammation are proposed to play a central role in COVID-19 pathogenesis. Mesenchymal stem cells (MSCs) have been shown to possess a comprehensive powerful immunomodulatory function. Intravenous infusion of MSCs has shown promising results in COVID-19 treatment. Here, we report a case of a severe COVID-19 patient treated with human umbilical cord Wharton's jelly-derived MSCs (hWJCs) from a healthy donor in Liaocheng People's Hospital, China, from February 24, 2020. The pulmonary function and symptoms of the patient with COVID-19 pneumonia was significantly improved in 2 days after hWJC transplantation, and recovered and discharged in 7 days after treatment. After treatment, the percentage and counts of lymphocyte subsets (CD3+, CD4+, and CD8+ T cell) were increased, and the level of IL-6, TNF-α, and C-reactive protein is significantly decreased after hWJC treatment. Thus, the intravenous transplantation of hWJCs was safe and effective for the treatment of patients with COVID-19 pneumonia, especially for the patients in a critically severe condition. This report highlights the potential of hWJC infusions as an effective treatment for COVID-19 pneumonia.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Neumonía Viral/terapia , Betacoronavirus/genética , Proteína C-Reactiva/inmunología , Proteína C-Reactiva/metabolismo , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/inmunología , Humanos , Inmunomodulación , Infusiones Intravenosas , Interleucina-6/sangre , Interleucina-6/inmunología , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/virología , Masculino , Células Madre Mesenquimatosas/inmunología , Persona de Mediana Edad , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/inmunología , SARS-CoV-2 , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/inmunología , Cordón Umbilical/citología , Cordón Umbilical/inmunología , Gelatina de Wharton/citología , Gelatina de Wharton/inmunología , Tratamiento Farmacológico de COVID-19
18.
Radiology ; 296(2): E65-E71, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32191588

RESUMEN

Background Coronavirus disease 2019 (COVID-19) has widely spread all over the world since the beginning of 2020. It is desirable to develop automatic and accurate detection of COVID-19 using chest CT. Purpose To develop a fully automatic framework to detect COVID-19 using chest CT and evaluate its performance. Materials and Methods In this retrospective and multicenter study, a deep learning model, the COVID-19 detection neural network (COVNet), was developed to extract visual features from volumetric chest CT scans for the detection of COVID-19. CT scans of community-acquired pneumonia (CAP) and other non-pneumonia abnormalities were included to test the robustness of the model. The datasets were collected from six hospitals between August 2016 and February 2020. Diagnostic performance was assessed with the area under the receiver operating characteristic curve, sensitivity, and specificity. Results The collected dataset consisted of 4352 chest CT scans from 3322 patients. The average patient age (±standard deviation) was 49 years ± 15, and there were slightly more men than women (1838 vs 1484, respectively; P = .29). The per-scan sensitivity and specificity for detecting COVID-19 in the independent test set was 90% (95% confidence interval [CI]: 83%, 94%; 114 of 127 scans) and 96% (95% CI: 93%, 98%; 294 of 307 scans), respectively, with an area under the receiver operating characteristic curve of 0.96 (P < .001). The per-scan sensitivity and specificity for detecting CAP in the independent test set was 87% (152 of 175 scans) and 92% (239 of 259 scans), respectively, with an area under the receiver operating characteristic curve of 0.95 (95% CI: 0.93, 0.97). Conclusion A deep learning model can accurately detect coronavirus 2019 and differentiate it from community-acquired pneumonia and other lung conditions. © RSNA, 2020 Online supplemental material is available for this article.


Asunto(s)
Inteligencia Artificial , Betacoronavirus , Infecciones por Coronavirus/diagnóstico por imagen , Neumonía Viral/diagnóstico por imagen , Adulto , Anciano , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico/métodos , Infecciones Comunitarias Adquiridas/diagnóstico por imagen , Infecciones por Coronavirus/diagnóstico , Aprendizaje Profundo , Diagnóstico Diferencial , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Persona de Mediana Edad , Pandemias , Curva ROC , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Estudios Retrospectivos , SARS-CoV-2 , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/métodos
19.
Bioelectrochemistry ; 132: 107411, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31862536

RESUMEN

A novel liposomal nanocomposite, Au@PIL-cerasome, with biocompatibility and conductivity was fabricated via the self-assembly of cerasomes and gold nanoparticles (AuNPs) stabilized by poly(ionic liquid)s (PILs). The surface charge, morphology and chemical composition of the nanocomposites were characterized by the zeta potential, UV-vis, TEM, SEM and EDS. The nanocomposites exhibited structural stability directly on the surface of solid electrodes, without fusion. Electrochemical impedance experiments demonstrated that the nanocomposites had an enhanced conductivity compared with unmodified cerasomes. Horseradish peroxidase (HRP), as a reporter, was immobilized on the nanocomposites without denaturation or inactivation. The direct electron transfer of HRP was achieved, and the HRP/Au@PIL-cerasome/GCE exhibited an amplified current and improved electrocatalytic activity. Activity towards H2O2 displayed a linear range over 10-70 µM and a detection limit of 3.3 µM. Activity towards NO2- displayed linear ranges over 1-5 mM and 5-1280 mM, and the limit of detection was 0.11 mM. In addition, the electrode was stable and reproducible, with 6% RSD. Such multi-component liposomal nanocomposites with an enhanced electrical performance pave a better way for building novel and straightforward 3D stereo biomimetic electrochemical platforms and even molecular communication systems to investigate information transduction between cells.


Asunto(s)
Biomimética , Técnicas Electroquímicas/métodos , Oro/química , Líquidos Iónicos/química , Nanopartículas del Metal/química , Propiedades de Superficie
20.
ACS Appl Mater Interfaces ; 11(10): 10153-10162, 2019 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-30821141

RESUMEN

Ultrathin two-dimensional NiS/Ni(OH)2 nanosheets (NiS/Ni(OH)2 NSs) were successfully filled within the hollow interiors of ammonium polyacrylate-functionalized polypyrrole nanotubes (NH4PA/PPyNTs) by a simple solvothermal method. This kind of novel hierarchical nanostructures with typical structural features of a nanoconfined system, denoted by NiS/Ni(OH)2/NH4PA/PPyNTs, were prepared by two main sections: polyacrylic acid (PAA) was first polymerized on PPyNTs containing vinyl groups, and the obtained PAA/PPyNTs exhibited a typical Janus structure, whose external surface was covered with carboxyl groups and the internal surface was still covered with PPy chains; second, Ni2+ ions as a precursor were facilely combined with -NH- segments in PPy chains by the coordination interaction under the solvothermal environment; therefore, NiS/Ni(OH)2 NSs (<1 nm) were well distributed on the internal surface of NH4PA/PPyNTs by the in situ growth. Because of the synergistic effects of ionizable NH4PA, PPy with good conductivity, NiS and Ni(OH)2 with electrocatalytical activity, as well as the nanoconfinement effect, the obtained NiS/Ni(OH)2@NH4PA/PPyNTs exhibited excellent electrocatalytic performance for detecting glucose. Sufficiently thin shells composed of ionizable NH4PA and good conductive PPyNTs can not only promote the electronic transmission effectively during the electrochemical detection of glucose but also hardly limit the transport of glucose and products. In addition, ultrathin NiS/Ni(OH)2 NSs may further enhance the electrocatalytic performance for glucose because of the more exposed active sites with the large surface area. Therefore, NiS/Ni(OH)2@NH4PA/PPyNTs can be applied as a good electrode material with stability and sensitivity for building a nonenzymatic glucose sensor.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Glucosa/aislamiento & purificación , Nanotubos/química , Resinas Acrílicas/química , Compuestos de Amonio/química , Glucosa/química , Humanos , Nanocompuestos/química , Níquel/química , Polímeros/química , Pirroles/química
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