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1.
Plant Cell ; 36(3): 709-726, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38000892

RESUMEN

Fruit softening, an irreversible process that occurs during fruit ripening, can lead to losses and waste during postharvest transportation and storage. Cell wall disassembly is the main factor leading to loss of fruit firmness, and several ripening-associated cell wall genes have been targeted for genetic modification, particularly pectin modifiers. However, individual knockdown of most cell wall-related genes has had minimal influence on cell wall integrity and fruit firmness, with the notable exception of pectate lyase. Compared to pectin disassembly, studies of the cell wall matrix, the xyloglucan-cellulose framework, and underlying mechanisms during fruit softening are limited. Here, a tomato (Solanum lycopersicum) fruit ripening-associated α-expansin (SlExpansin1/SlExp1) and an endoglucanase (SlCellulase2/SlCel2), which function in the cell wall matrix, were knocked out individually and together using clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9-mediated genome editing. Simultaneous knockout of SlExp1 and SlCel2 enhanced fruit firmness, reduced depolymerization of homogalacturonan-type pectin and xyloglucan, and increased cell adhesion. In contrast, single knockouts of either SlExp1 or SlCel2 did not substantially change fruit firmness, while simultaneous overexpression of SlExp1 and SlCel2 promoted early fruit softening. Collectively, our results demonstrate that SlExp1 and SlCel2 synergistically regulate cell wall disassembly and fruit softening in tomato.


Asunto(s)
Celulasa , Solanum lycopersicum , Frutas/metabolismo , Solanum lycopersicum/genética , Celulasa/genética , Celulasa/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pectinas/metabolismo , Pared Celular/metabolismo
2.
Plant J ; 119(3): 1433-1448, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38922743

RESUMEN

Anthocyanins are natural pigments and dietary antioxidants that play multiple biological roles in plants and are important in animal and human nutrition. Low temperature (LT) promotes anthocyanin biosynthesis in many species including blood orange. A retrotransposon in the promoter of Ruby1, which encodes an R2R3 MYB transcription factor, controls cold-induced anthocyanin accumulation in blood orange flesh. However, the specific mechanism remains unclear. In this study, we characterized two LT-induced ETHYLENE RESPONSE FACTORS (CsERF054 and CsERF061). Both CsERF054 and CsERF061 can activate the expression of CsRuby1 by directly binding to a DRE/CRT cis-element within the retrotransposon in the promoter of CsRuby1, thereby positively regulating anthocyanin biosynthesis. Further investigation indicated that CsERF061 also forms a protein complex with CsRuby1 to co-activate the expression of anthocyanin biosynthetic genes, providing a dual mechanism for the upregulation of the anthocyanin pathway. These results provide insights into how LT mediates anthocyanin biosynthesis and increase the understanding of the regulatory network of anthocyanin biosynthesis in blood orange.


Asunto(s)
Antocianinas , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Regiones Promotoras Genéticas , Retroelementos , Factores de Transcripción , Antocianinas/biosíntesis , Antocianinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Retroelementos/genética , Etilenos/metabolismo , Etilenos/biosíntesis , Frío , Citrus/genética , Citrus/metabolismo
3.
J Exp Bot ; 75(20): 6625-6643, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39086268

RESUMEN

Changes in both lignin biosynthesis and DNA methylation have been reported to be associated with chilling stress in plants. When stored at low temperatures, red-fleshed loquat is prone to lignification, with increased lignin content and fruit firmness, which has deleterious effects on taste and eating quality. Here, we found that 5 °C storage mitigated the increasing firmness and lignin content of red-fleshed 'Dahongpao' ('DHP') loquat fruit that occurred during 0 °C storage. EjNAC5 was identified by integrating RNA sequencing with whole-genome bisulfite sequencing analysis of 'DHP' loquat fruit. The transcript levels of EjNAC5 were positively correlated with changes in firmness and negatively correlated with changes in DNA methylation level of a differentially methylated region in the EjNAC5 promoter. In white-fleshed 'Baisha' ('BS') loquat fruit, which do not undergo chilling-induced lignification at 0 °C, the transcripts of EjNAC5 remained low and the methylation level of the differentially methylated region in the EjNAC5 promoter was higher, compared with 'DHP' loquat fruit. Transient overexpression of EjNAC5 in loquat fruit and stable overexpression in Arabidopsis and liverwort led to an increase in lignin content. Furthermore, EjNAC5 interacts with EjERF39 and EjHB1 and activates the transcription of Ej4CL1 and EjPRX12 genes involved in lignin biosynthesis. This regulatory network involves different transcription factors from those involved in the lignification pathway. Our study indicates that EjNAC5 promoter methylation modulates EjNAC5 transcript levels and identifies novel EjNAC5-EjERF39-Ej4CL1 and EjNAC5-EjHB1-EjPRX12 regulatory modules involved in chilling induced-lignification.


Asunto(s)
Frío , Eriobotrya , Frutas , Lignina , Proteínas de Plantas , Factores de Transcripción , Eriobotrya/genética , Eriobotrya/metabolismo , Eriobotrya/fisiología , Frutas/genética , Frutas/metabolismo , Lignina/metabolismo , Lignina/biosíntesis , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Metilación de ADN
4.
Opt Lett ; 49(16): 4749-4752, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39146151

RESUMEN

In this Letter, we demonstrate terahertz (THz) magnetic field detection in fused silica with sensitivity that can be easily controlled by sample tilting (for both amplitude and polarization). The proposed technique remains in the linear regime at magnetic fields exceeding 0.3 T (0.9 MV/cm of equivalent electric field) and allows the use of low-cost amorphous materials. Furthermore, the demonstrated effects should be present in a wide variety of materials used as substrates in different THz-pump laser-probe experiments and need to be considered in order to disentangle different contributions to the measured signals.

5.
Skin Res Technol ; 30(8): e13919, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39113612

RESUMEN

BACKGROUND: Diabetes mellitus (DM) presents impediment to wound healing. While ultraviolet B (UVB) exposure showed therapeutic potential in various skin conditions, its capacity to mediate diabetic wound healing remains unclear. To investigate the efficacy of UVB on wound healing and its underlying basis. MATERIALS AND METHODS: Male C57BL/6 mice were subjected to the high-fat diet followed by streptozotocin administration to establish the diabetic model. Upon confirmation of diabetes, full-thickness wounds were inflicted and the treatment group received UVB radiation at 50 mJ/cm2 for 5 min every alternate day for 2 weeks. Wound healing rate was then assessed, accompanied by evaluations of blood glucose, lipid profiles, CD31 expression, and concentrations of ghrelin and leptin. Concurrently, in vitro studies were executed to evaluate the protective role of ghrelin on human umbilical vein endothelial cells (HUVEC) under high glucose (HG) conditions. RESULTS: Post UVB exposure, there was a marked acceleration in wound healing in DM mice without alterations in hyperglycemia and lipid profiles. Compared to non-UVB-exposed mice, the UVB group showed enhanced angiogenesis manifested by a surge in CD31 expression. This trend appeared to be in harmony with the elevated ghrelin levels. In vitro experiments indicated that ghrelin significantly enhanced the migratory pace and angiogenic properties of HUVEC under HG-induced stress, potentially mediated by an upregulation in vascular endothelial growth factor expression. CONCLUSION: UVB exposure bolstered wound healing in diabetic mice, plausibly mediated through augmented angiogenesis induced by ghrelin secretion. Such findings underscore the vast potential of UVB-induced ghrelin in therapeutic strategies targeting diabetic wound healing.


Asunto(s)
Diabetes Mellitus Experimental , Ghrelina , Células Endoteliales de la Vena Umbilical Humana , Ratones Endogámicos C57BL , Cicatrización de Heridas , Animales , Humanos , Masculino , Ratones , Glucemia/metabolismo , Ghrelina/metabolismo , Ghrelina/efectos de la radiación , Leptina/metabolismo , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Piel/efectos de la radiación , Piel/patología , Piel/metabolismo , Rayos Ultravioleta/efectos adversos , Terapia Ultravioleta/métodos , Cicatrización de Heridas/efectos de la radiación
6.
Ren Fail ; 46(1): 2310081, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38321925

RESUMEN

Background and purpose: Acute kidney injury (AKI) is a common serious complication in sepsis patients with a high mortality rate. This study aimed to develop and validate a predictive model for sepsis associated acute kidney injury (SA-AKI). Methods: In our study, we retrospectively constructed a development cohort comprising 733 septic patients admitted to eight Grade-A tertiary hospitals in Shanghai from January 2021 to October 2022. Additionally, we established an external validation cohort consisting of 336 septic patients admitted to our hospital from January 2017 to December 2019. Risk predictors were selected by LASSO regression, and a corresponding nomogram was constructed. We evaluated the model's discrimination, precision and clinical benefit through receiver operating characteristic (ROC) curves, calibration plots, decision curve analysis (DCA) and clinical impact curves (CIC) in both internal and external validation. Results: AKI incidence was 53.2% in the development cohort and 48.2% in the external validation cohort. The model included five independent indicators: chronic kidney disease stages 1 to 3, blood urea nitrogen, procalcitonin, D-dimer and creatine kinase isoenzyme. The AUC of the model in the development and validation cohorts was 0.914 (95% CI, 0.894-0.934) and 0.923 (95% CI, 0.895-0.952), respectively. The calibration plot, DCA, and CIC demonstrated the model's favorable clinical applicability. Conclusion: We developed and validated a robust nomogram model, which might identify patients at risk of SA-AKI and promising for clinical applications.


Asunto(s)
Lesión Renal Aguda , Sepsis , Humanos , Nomogramas , Estudios Retrospectivos , China
7.
Helicobacter ; 28(2): e12946, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36633162

RESUMEN

OBJECTIVE: The aim of this pilot study was to evaluate the efficacy and safety of intravenous use esomeprazole, metronidazole, and/or levofloxacin in the treatment of Helicobacter pylori (H. pylori)-associated peptic ulcer complications. METHODS: Inpatients with peptic ulcer complications who were not able to take oral medicine were randomly assigned to three groups: triple therapy (esomeprazole, levofloxacin, metronidazole) and dual therapy (esomeprazole, levofloxacin/metronidazole) for 7 days. After intravenous treatment, all patients received open-label oral esomeprazole 20 mg bid for another 1 month. All subjects were followed up for gastroscopy at the seventh day of intravenous treatment to confirm the ulcer healing and 13 C-urea breath test to confirm successful H. pylori eradication 4-6 weeks after completion of oral esomeprazole therapy. RESULTS: The H. pylori eradication rate of both LEV-dual therapy (33.3%, 95% CI: 9.7%-70.0%) and MTZ-dual therapy (50%, 95% CI: 21.5%-78.5%) was significantly lower than that of triple therapy (95%, 95% CI: 71.1%-97.4%) (p = .003, .016). There were no significant differences in the adverse effects among all treatment groups, and the adverse effects were rare. CONCLUSIONS: The intravenous triple regimen, consisting of proton-pump inhibitor, metronidazole, and levofloxacin, could be considered in patients of H. pylori-associated peptic ulcer complications if oral medicine cannot be provided.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Úlcera Péptica , Humanos , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Quimioterapia Combinada , Esomeprazol/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Levofloxacino/farmacología , Metronidazol/uso terapéutico , Úlcera Péptica/tratamiento farmacológico , Proyectos Piloto
8.
J Dairy Sci ; 105(12): 9450-9462, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36207178

RESUMEN

Foodborne pathogens detection is important to ensure food safety and human health. In this study, we designed a comet structure to rapidly and sensitively detect foodborne Listeria monocytogenes. This method combined isothermal sequence exchange amplification (SEA) and surface-enhanced Raman spectroscopy. Listeria monocytogenes DNA could be rapidly amplified at a constant temperature via SEA with a pair of modified primers, which rendered the precise thermal control instrumentation unnecessary. Efficient SEA amplification generated a large number of DNA duplexes that could be easily captured by streptavidin-modified magnetic bead and AuMB@Ag-isothiocyanate fluorescein antibody (anti-FITC). AuMB@Ag-anti-FITC was used as a signal probe, which generated a significant excitation signal at 1,616 cm-1 for quantitative detection and analysis. The results displayed sensitive detection of L. monocytogenes in cheese from 2.0 × 101 cfu/mL to 2.0 × 106 cfu/mL within 1.0 h with a detection limit of 7.8 cfu/mL. Furthermore, this comet structure displayed the desirable specificity as its specific primers and amplified DNA ends were attached to streptavidin-modified magnetic beads and AuMB@Ag-anti-FITC, respectively. We expected that the method devised would provide a promising new approach to screening for L. monocytogenes and guarantee the microbiological safety of dairy products.


Asunto(s)
Queso , Contaminación de Alimentos , Listeria monocytogenes , Queso/microbiología , Cartilla de ADN/genética , Microbiología de Alimentos , Listeria monocytogenes/aislamiento & purificación , Espectrometría Raman , Estreptavidina
9.
Funct Integr Genomics ; 21(3-4): 421-433, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34009538

RESUMEN

This study analyzed the difference between biofilm and planktonic Brucella abortus using metabolomics and proteomics. Brucella abortus was cultured in different media to induce Brucella abortus biofilm formation and planktonic cells, followed by metabolomics and proteomics analyses for these two samples. Significant differential metabolites were identified, followed by KEGG pathway analysis. Differentially expressed proteins were identified, followed by subcellular localization, GO annotation, and KEGG pathway enrichment. Additionally, a correlation analysis of metabolomics and proteomics was performed. Metabolomics analysis showed 7682 positive and 4433 negative metabolites, including 188 positive and 117 negative significant differential metabolites. These differential metabolites were enriched in fatty acid/unsaturated fatty acid biosynthesis and linoleic acid metabolism. Proteomics analysis revealed 1759 proteins, including 486 differentially expressed proteins, which were enriched in various metabolic and degradation-related pathways. Subcellular localization showed that 74.3% of the differential proteins were cytoplasmic proteins. Correlation analysis showed that 1-palmitoyl-2-oleoyl-phosphatidylglycerol had the most significant correlations with proteins, followed by cytosine. Both metabolites correlated with the protein Q57EI7 (RbsB-1, ribose ABC transporter). One common pathway, fatty acid biosynthesis, was identified by both proteomics and metabolomics analyses that involved the metabolites, oleic acid, and protein Q57DK3 (biotin carboxylase). There were metabolomic and proteomic differences between Brucella abortus biofilm and planktonic cells, and these results provide novel insights into the biofilm-forming process of Brucella abortus.


Asunto(s)
Biopelículas , Brucella abortus , Metabolómica , Plancton , Proteómica , Transportadoras de Casetes de Unión a ATP , Brucella abortus/genética , Brucella abortus/metabolismo , Ácidos Grasos , Plancton/microbiología
10.
Respir Res ; 22(1): 130, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33910578

RESUMEN

BACKGROUND: Fibrinogen is the first qualified prognostic/predictive biomarker for exacerbations in patients with chronic obstructive pulmonary disease (COPD). The IMPACT trial investigated fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) triple therapy versus FF/VI and UMEC/VI in patients with symptomatic COPD at risk of exacerbations. This analysis used IMPACT trial data to examine the relationship between fibrinogen levels and exacerbation outcomes in patients with COPD. METHODS: 8094 patients with a fibrinogen assessment at Week 16 were included, baseline fibrinogen data were not measured. Post hoc analyses were performed by fibrinogen quartiles and by 3.5 g/L threshold. Endpoints included on-treatment exacerbations and adverse events of special interest (AESIs). RESULTS: Rates of moderate, moderate/severe, and severe exacerbations were higher in the highest versus lowest fibrinogen quartile (0.75, 0.92 and 0.15 vs 0.67, 0.79 and 0.10, respectively). The rate ratios (95% confidence interval [CI]) for exacerbations in patients with fibrinogen levels ≥ 3.5 g/L versus those with fibrinogen levels < 3.5 g/L were 1.03 (0.95, 1.11) for moderate exacerbations, 1.08 (1.00, 1.15) for moderate/severe exacerbations, and 1.30 (1.10, 1.54) for severe exacerbations. There was an increased risk of moderate/severe exacerbation (hazard ratio [95% CI]: highest vs lowest quartile 1.16 [1.04, 1.228]; ≥ 3.5 g/L vs < 3.5 g/L: 1.09 [1.00, 1.16]) and severe exacerbation (1.35 [1.09, 1.69]; 1.27 [1.08, 1.47], respectively) with increasing fibrinogen level. Cardiovascular AESIs were highest in patients in the highest fibrinogen quartile. CONCLUSIONS: Rate and risk of exacerbations was higher in patients with higher fibrinogen levels. This supports the validity of fibrinogen as a predictive biomarker for COPD exacerbations, and highlights the potential use of fibrinogen as an enrichment strategy in trials examining exacerbation outcomes. TRIAL REGISTRATION: NCT02164513.


Asunto(s)
Fibrinógeno/metabolismo , Pulmón/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/sangre , Anciano , Biomarcadores/sangre , Broncodilatadores/uso terapéutico , Progresión de la Enfermedad , Método Doble Ciego , Combinación de Medicamentos , Femenino , Humanos , Pulmón/efectos de los fármacos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Regulación hacia Arriba
11.
Mol Cell Biochem ; 476(1): 93-107, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32845436

RESUMEN

Mesenchymal stem cells (MSCs) can alleviate acute respiratory distress syndrome (ARDS), but the mechanisms involved are unclear, especially about their specific effects on cellular mitochondrial respiratory function. Thirty mice were allocated into the Control, LPS, and LPS + Bone marrow mesenchymal stem cell (BMSC) group (n = 10/group). Mouse alveolar epithelial cells (MLE-12) and macrophage cells (RAW264.7) were divided into the same groups. Pathological variation, inflammation-related factors, reactive oxygen species (ROS), ATP levels, and oxygen consumption rate (OCR) were analyzed. Pathologic features of ARDS were observed in the LPS group and were significantly alleviated by BMSCs. The trend in inflammation-related factors among the three groups was the LPS group > LPS + BMSC group > Control group. In the MLE-12 co-culture system, IL-6 was increased in the LPS group but not significantly reduced in the LPS + BMSC group. In the RAW264.7 co-culture system, IL-1ß, TNF-α, and IL-10 levels were all increased in the LPS group, IL-1ß and TNF-α levels were reduced by BMSCs, while IL-10 level kept increasing. ROS and ATP levels were increased and decreased respectively in both MLE-12 and RAW264.7 cells in the LPS groups but reversed by BMSCs. Basal OCR, ATP-linked OCR, and maximal OCR were lower in the LPS groups. Impaired basal OCR and ATP-linked OCR in MLE-12 cells were partially restored by BMSCs, while impaired basal OCR and maximal OCR in RAW264.7 cells were restored by BMSCs. BMSCs improved the mitochondrial respiration dysfunction of macrophages and alveolar epithelial cells induced by LPS, alleviated lung tissue injury, and inflammatory response in a mouse model of ARDS.


Asunto(s)
Epitelio/metabolismo , Células Madre Mesenquimatosas/citología , Mitocondrias/metabolismo , Alveolos Pulmonares/metabolismo , Síndrome de Dificultad Respiratoria/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Células de la Médula Ósea/citología , Técnicas de Cocultivo , Inflamación , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/metabolismo , Lesión Pulmonar/metabolismo , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Consumo de Oxígeno , Células RAW 264.7
12.
Analyst ; 146(13): 4280-4289, 2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34105526

RESUMEN

Herein, a simple and facile one-step hydrothermal carbonization synthesis procedure for the fabrication of N, Cu-doped carbon quantum dots (N, Cu-CQDs) as a peroxidase-mimicking enzyme was reported. The peroxidase-like performance of N, Cu-CQDs was assessed based on the oxidative coupling reaction of phenol with 4-aminoantipyrine (4-AAP) in the presence of hydrogen peroxide (H2O2). The N, Cu-CQDs/4-AAP/H2O2 system was applied to sensing phenol based on double signals of absorption spectra (or colorimetric visualization) as well as fluorescence spectra. The obtained limits of detection (LODs) were as low as 0.12 µM and 0.02 µM, respectively. Moreover, the proposed method was successfully applied to the determination of phenol in sewage with satisfactory recovery. Our results demonstrate that the N, Cu-CQDs/4-AAP/H2O2/phenol sensing system has a great potential prospect for applications in environmental chemistry and biotechnology.


Asunto(s)
Puntos Cuánticos , Carbono , Cobre , Peróxido de Hidrógeno , Nitrógeno , Peroxidasas , Fenol , Fenoles
13.
Sensors (Basel) ; 21(3)2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33498582

RESUMEN

This paper proposes a joint encryption and screen-cam robust watermarking scheme. This method combines the advantages of smartphone, encryption and watermarking technologies, thereby achieving watermark extraction with a smartphone, partial decryption and tracking leakage from sneak shots. We design a dual watermarking algorithm to achieve watermark detection from both encrypted and decrypted images. First, a watermark is embedded in the discrete Fourier transform (DFT) domain to enable leakage tracking. Then, a second watermark is generated based on QR (Quick response) code encoding and inverse DFT to achieve high watermark capacity and error correction ability, where the secret key for decryption is included in the watermark message. By hiding this message carrying the watermark for the encrypted image in the changes caused by embedding the first watermark, we can improve imperceptibility and will not affect the effectiveness of the proposed scheme. Finally, to enhance the robustness of watermark after encryption, a chaotic mapping-based segment encryption algorithm is proposed. In the process of watermark detection, to cope with perspective correction, a frame locating based algorithm is employed to achieve watermark synchronization from a recaptured picture of the encrypted image. Considering the severe quality degradation, we use a noise component and local statistic feature-based method to extract the message bits. The experimental results show that the proposed scheme is secure, and highly robust, to screen-cam the process for both before and after decryption. Additionally, after decryption, the proposed scheme also has high robustness against common image processing attacks.

14.
Opt Express ; 28(8): 11609-11617, 2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32403668

RESUMEN

Using a Dazzler system and tilting a compressor grating, we provide an effective way of using the laser group delay dispersion to continuously steer the electron beam accelerated by an asymmetric laser wakefield. The deviation angle of the electron beam was the same as that of the angularly chirped laser pulse from its initial optical axis, which is determined by the laser pulse-front-tilt (PFT). This method can be utilized to continuously control over the pointing direction of electron bunches to the requisite trajectories, especially for practical applications in highly sensitive alignment devices such as electron-positron colliders or undulators. Additionally, we investigate the effect of PFT on the properties of the electron beam.

15.
Respir Res ; 21(1): 131, 2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32471423

RESUMEN

BACKGROUND: The comparative efficacy of inhaled corticosteroid/long-acting muscarinic antagonist/long-acting ß2-agonist (ICS/LAMA/LABA) triple therapy administered via single or multiple inhalers in patients with chronic obstructive pulmonary disease (COPD) has not been evaluated comprehensively. We conducted two replicate trials comparing single- with multiple-inhaler ICS/LAMA/LABA combination in COPD. METHODS: 207608 and 207609 were Phase IV, 12-week, randomized, double-blind, triple-dummy non-inferiority trials comparing once-daily fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) 100/62.5/25 µg via Ellipta inhaler, with twice-daily budesonide/formoterol (BUD/FOR) 400/12 µg via metered-dose inhaler plus once-daily tiotropium (TIO) 18 µg via HandiHaler. Patients had symptomatic COPD and forced expiratory volume in 1 s (FEV1) < 50% predicted, or FEV1 < 80% predicted and ≥ 2 moderate or 1 severe exacerbations in the prior year. The primary endpoint in both trials was weighted mean change from baseline (wmCFB) in 0-24-h FEV1 at Week 12. Secondary endpoints included CFB in trough FEV1 at Day 84 and 85. Other endpoints included serial FEV1 and health status outcomes at Week 12. Safety was evaluated descriptively. RESULTS: The modified per-protocol population included 720 and 711 patients in studies 207608 and 207609 (intent-to-treat population: 728 and 732). FF/UMEC/VI was non-inferior to BUD/FOR+TIO for wmCFB in 0-24-h FEV1 at Week 12 (Study 207608 treatment difference [95% confidence interval]: 15 mL [- 13, 43]; Study 207609: 11 mL [- 20, 41]). FF/UMEC/VI improved trough FEV1 CFB versus BUD/FOR+TIO at Day 84 and 85 (Day 85 treatment difference: Study 207608: 38 mL [10, 66]; Study 207609: 51 mL [21, 82]) and FEV1 at 12 and 24 h post-morning dose at Week 12 in both studies. No treatment differences were seen in health status outcomes. Safety profiles were similar between treatments; pneumonia occurred in 7 (< 1%) patients with FF/UMEC/VI and 9 (1%) patients with BUD/FOR+TIO, across both studies. CONCLUSIONS: FF/UMEC/VI was non-inferior to BUD/FOR+TIO for wmCFB in 0-24-h FEV1 at Week 12 in patients with COPD. Greater improvements in trough and serial FEV1 measurements at Week 12 with FF/UMEC/VI versus BUD/FOR+TIO, together with similar health status improvements and safety outcomes including the incidence of pneumonia, suggest that once-daily single-inhaler FF/UMEC/VI triple therapy is a viable option for patients looking to simplify their treatment regimen. TRIAL REGISTRATION: GSK (207608/207609; NCT03478683/NCT03478696).


Asunto(s)
Broncodilatadores/administración & dosificación , Estado de Salud , Pulmón/fisiología , Nebulizadores y Vaporizadores , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Administración por Inhalación , Anciano , Androstadienos/administración & dosificación , Combinación Budesonida y Fumarato de Formoterol/administración & dosificación , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Pulmón/efectos de los fármacos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Resultado del Tratamiento
16.
Anal Bioanal Chem ; 412(4): 963-972, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31853600

RESUMEN

In this study, palladium/carbon dot composites (Pd-CDs) were fabricated via a facial hydrothermal route using ethanediamine and palladium chloride dihydrate as precursors. The obtained Pd-CDs showed an excellent intrinsic peroxidase-like activity, which could catalyze the oxidization of 3,3'5,5'-tetramethylbenzidine with the assistance of hydrogen peroxide (H2O2) and thus resulted in color change, accompanied by an absorption peak which appeared at 652 nm. Such response is H2O2 concentration-dependent and allows for the assay of H2O2 in the range of 0.1 to 30 µM with a limit of detection of 0.03 µM. Simultaneously, by combination of enzymatic oxidation of glucose with glucose oxidase and Pd-CD catalytic reaction, a colorimetric sensing platform was also constructed for glucose detection with high selectivity and sensitivity (limit of detection as low as 0.2 µM). Additionally, the proposed method exhibited capability for determination of glucose in real samples (fruit juice) with satisfactory recovery (98.5-103%), indicating potential application prospects in biochemical analysis.


Asunto(s)
Carbono/química , Glucosa/análisis , Peróxido de Hidrógeno/análisis , Paladio/química , Bencidinas/química , Materiales Biomiméticos/química , Técnicas Biosensibles/métodos , Colorimetría/métodos , Análisis de los Alimentos/métodos , Jugos de Frutas y Vegetales/análisis , Límite de Detección , Oxidación-Reducción , Peroxidasa/química
17.
Med Sci Monit ; 26: e926815, 2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-33166272

RESUMEN

BACKGROUND Cardiopulmonary resuscitation (CPR) is a topic of great scientific and clinical interest that has received much attention in the past decade. Our study aimed to predict the trends in CPR research activities and evaluate hot topics via bibliometric means, quantitatively and qualitatively. MATERIAL AND METHODS All data were collected from a search of the Web of Science Core Collection on May 12, 2020. Retrieved information was investigated with bibliometric analysis by CiteSpace and VOSviewer software and the Online Analysis Platform of Literature Metrology to analyze and predict the trends and hotspots in this field. RESULTS Our search returned a total of 9563 articles and reviews on CPR published from 2010 through 2019. The number of original research studies on CPR has been increasing annually. The journal Resuscitation published the greatest number of manuscripts involved CPR, and the leading country and institution with regard to contributions on CPR were the United States and the University of Pennsylvania. Keyword co-occurrence/co-citation-cluster analysis showed that the most popular terms associated with CPR occurred in the manner of cluster labels, such as therapeutic hypothermia and treatment recommendation, among others. In addition, palliative care, sepsis, extracorporeal membrane oxygenation, and brain injury were identified as new foci through burst detection analysis. CONCLUSIONS Our study showed that the scientific research focus on CPR is switching from traditional therapeutic treatments to a public health practice, with in-depth understanding and development of CPR-related techniques expanding over the past decade. These results demonstrate trends in the CPR research and detected the possible neo-foci for ensuing research.


Asunto(s)
Bibliometría , Investigación Biomédica/tendencias , Reanimación Cardiopulmonar/tendencias , Autoria , Análisis por Conglomerados , Humanos , Internacionalidad , Publicaciones Periódicas como Asunto
18.
Opt Express ; 27(21): 29676-29684, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31684225

RESUMEN

Laser wakefield accelerators have emerged as a promising candidate for compact synchrotron radiation and even x-ray free electron lasers. Today, to make the electrons emit electromagnetic radiation, the trajectories of laser wakefield accelerated electrons are deflected by transverse wakefield, counter-propagating laser field or external permanent magnet insertion device. Here, we propose a novel type of undulator that has a period of a few hundred microns and a magnetic field of tens of Tesla. The undulator consists of a bifilar capacitor-coil target that sustains a strong discharge current that generates a helical magnetic field around the coil axis when irradiated by a high-energy laser. Coupling this undulator with state-of-the-art laser wakefield accelerators can, simultaneously, produce ultra-bright quasi-monochromatic x-rays with tunable energy ranging 5-250 keV and optimize the free electron laser parameter and gain length compared with a permanent magnet-based undulator. This concept may pave a path toward ultra-compact synchrotron radiation and even x-ray free electron lasers.

19.
J Exp Bot ; 70(3): 925-936, 2019 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-30481327

RESUMEN

The monoterpene linalool is a major contributor to aroma and flavor in peach (Prunus persica) fruit. It accumulates during fruit ripening, where up to ~40% of the compound is present in a non-volatile glycosylated form, which affects flavor quality and consumer perception by retronasal perception during tasting. Despite the importance of this sequestration to flavor, the UDP-glycosyltransferase (UGT) responsible for linalool glycosylation has not been identified in peach. UGT gene expression during peach fruit ripening and among different peach cultivars was analyzed using RNA sequencing, and transcripts correlated with linalyl-ß-d-glucoside were selected as candidates for functional analysis. Kinetic resolution of a racemic mixture of R,S-linalool was shown for PpUGT85A2, with a slight preference for S-(+)-linalool. PpUGT85A2 was shown to catalyze synthesis of linalyl-ß-d-glucoside in vitro, although it did not exhibit the highest enzyme activity between tested substrates. Subcellular localization of PpUGT85A2 in the cytoplasm and nucleus was detected. Application of linalool to peach leaf disks promoted PpUGT85A2 expression and linalyl-ß-d-glucoside generation. Transient expression in peach fruit and stable overexpression in tobacco and Arabidopsis resulted in significant accumulation of linalyl-ß-d-glucoside in vivo. Taken together, the results indicate that PpUGT85A2 expression is a major control point predicting linalyl-ß-d-glucoside content.


Asunto(s)
Monoterpenos Acíclicos/metabolismo , Glucosiltransferasas/genética , Proteínas de Plantas/genética , Prunus persica/genética , Glucosiltransferasas/metabolismo , Glicosilación , Filogenia , Proteínas de Plantas/metabolismo , Prunus persica/metabolismo
20.
Analyst ; 144(2): 656-662, 2019 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-30484788

RESUMEN

In this paper, we have presented a novel strategy to fabricate Fe-doped carbon quantum dots (Fe-CQDs) for dopamine sensing applications. The Fe-CQDs are obtained by one step hydrothermal carbonization, using ethylenediamine tetraacetic acid salts and ferric nitrate as the carbon and iron source, which simultaneously incorporates Fe (dopamine-bonding site) and luminescent carbon quantum dots (fluorophores). The added dopamine containing catechol groups might form complexes with Fe ions (doped in CQDs) due to coordination. Subsequently, dopamine was oxidized to generate dopamine-quinone (a known potent electron acceptor) species by ambient O2. Thus, the coordination induced dopamine in proximity to the CQDs, which provided favourable electron acceptors in close proximity to the CQDs and produced high quenching efficiencies. Such fluorescence responses can be used for well quantifying dopamine in the range of 0.01-50 µM with a detection limit of 5 nM (S/N = 3). The proposed sensing system has been successfully used for the assay of dopamine in human urine samples. Preliminary cell image study indicates that the obtained Fe-CQDs possess high photostability and low cytotoxicity, which make them promising for biological applications.


Asunto(s)
Dopamina/análisis , Puntos Cuánticos/química , Espectrometría de Fluorescencia/métodos , Carbono/química , Supervivencia Celular/efectos de los fármacos , Dopamina/orina , Femenino , Células HeLa , Humanos , Hierro/química , Límite de Detección , Microscopía Confocal/métodos , Puntos Cuánticos/toxicidad , Reproducibilidad de los Resultados , Adulto Joven
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