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1.
J Am Chem Soc ; 146(19): 13025-13033, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38693826

RESUMEN

1,3,5-Trimethylenebenzene (1,3,5-TMB), a 3-fold-symmetric triradical with a high-spin ground state, is an attractive platform for investigating the unique spin properties of π-conjugated triangular triradicals. Here, we report the on-surface synthesis of N-heterocyclic carbene (NHC)-derived 1,3,5-TMB (N-TMB) via surface-assisted C-C and C-N coupling reactions on Au(111). The chemical and electronic structures of N-TMB on the Au(111) surface are revealed with atomic precision using scanning tunneling microscopy and noncontact atomic force microscopy, combined with density functional theory (DFT) calculations. It is demonstrated that there is substantial charge transfer between N-TMB and the substrate, resulting in a positively charged N-TMB on Au(111). DFT calculations at the UB3LYP/def2-TZVP level of theory and multireference method, e.g., CASSCF/NEVPT2, indicate that N-TMB possesses a doublet ground state with reduced Cs symmetry in the gas phase, contrasting the quartet ground state of 1,3,5-TMB with D3h symmetry, and exhibits a doublet-quartet energy gap of -0.80 eV. The incorporation of NHC structures and the extended π-conjugation promote the spin-orbital overlaps in N-TMB, leading to Jahn-Teller distortion and the formation of a robust doublet state. Our results not only demonstrate the fabrication of polyradicals based on NHC but also shed light on the effect of NHC and π-conjugation on the electronic structure and spin coupling, which opens up new possibilities for precisely regulating the spin-spin exchange coupling of organic polyradicals.

2.
BMC Pulm Med ; 24(1): 228, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730395

RESUMEN

OBJECTIVE: To explore the association between PaCO2 and noninvasive ventilation (NIV) failure in patients with hypoxemic respiratory failure. METHODS: A retrospective study was performed in a respiratory ICU of a teaching hospital. Patients admitted to ICU between 2011 and 2019 were screened. We enrolled the patients with hypoxemic respiratory failure. However, patients who used NIV due to acute-on-chronic respiratory failure or heart failure were excluded. Data before the use of NIV were collected. Requirement of intubation was defined as NIV failure. RESULTS: A total of 1029 patients were enrolled in final analysis. The rate of NIV failure was 45% (461/1029). A nonlinear relationship between PaCO2 and NIV failure was found by restricted cubic splines (p = 0.03). The inflection point was 32 mmHg. The rate of NIV failure was 42% (224/535) in patients with PaCO2 >32 mmHg. However, it increased to 48% (237/494) in those with PaCO2 ≤ 32 mmHg. The crude and adjusted hazard ratio (HR) for NIV failure was 1.36 (95%CI:1.13-1.64) and 1.23(1.01-1.49), respectively, if the patients with PaCO2 >32 mmHg were set as reference. In patients with PaCO2 ≤ 32 mmHg, one unit increment of PaCO2 was associated with 5% reduction of NIV failure. However, it did not associate with NIV failure in patients with PaCO2 >32 mmHg. CONCLUSIONS: PaCO2 and NIV failure was nonlinear relationship. The inflection point was 32 mmHg. Below the inflection point, lower PaCO2 was associated with higher NIV failure. However, it did not associate with NIV failure above this point.


Asunto(s)
Dióxido de Carbono , Hipoxia , Ventilación no Invasiva , Insuficiencia Respiratoria , Insuficiencia del Tratamiento , Humanos , Insuficiencia Respiratoria/terapia , Insuficiencia Respiratoria/sangre , Estudios Retrospectivos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Hipoxia/sangre , Hipoxia/terapia , Dióxido de Carbono/sangre , Unidades de Cuidados Intensivos , Anciano de 80 o más Años , Análisis de los Gases de la Sangre
3.
Br J Pharmacol ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721797

RESUMEN

Neuroinflammation is initiated in response to a variety of endogenous and exogenous sources. As the resident macrophages of the central nervous system, the polarization of microglia into either the M1 pro-inflammatory phenotype or the M2 anti-inflammatory phenotype holds great promise as a therapeutic strategy for neuroinflammation. Natural products, comprising a vital chemical library with distinctive structures and diverse functions, have been extensively employed to modulate microglial polarization for the treatment of neuroinflammation. In this review, we present up-to-date and extensive insights into the therapeutic effects and underlying mechanisms of natural products in the context of neuroinflammation. Furthermore, the review aims to present a new perspective by focusing on the targets of natural compounds, elucidating the molecular mechanisms and guiding the transition from natural-derived lead compounds to potential anti-neuroinflammatory drugs. Additionally, we provide a comprehensive overview of the challenges and limitations associated with the utilization of natural products for neuroinflammation therapy.

4.
Int Dent J ; 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38582717

RESUMEN

OBJECTIVE: To investigate changes in the upper maxillary palates of children with obstructive sleep apnoea (OSA) and mandibular retraction who were treated using modified twin-block appliances (MTBAs). METHODS: Thirty-five OSA children (age: 6-12 years) with mandibular retraction were included as the experimental group and 35 children who were Angle's class I but without mandibular retraction were included as the control group. The experimental group was treated with MTBA. Plaster models were made before the treatment and at the end of the 6-month treatment period. Plaster models of the control group were made at inclusion and after 6 months. Some plaster models were excluded because of damage or their failure to exhibit sufficiently clear marks, which left 26 pairs each for the experimental and control groups. The gender and age of the experimental group were matched with those of the control group at the end of the treatment. Three-dimensional (3D) digital model information was gathered using the external oral scanning model, and the data were extracted and analysed statistically to clarify the morphologic improvement in the maxillopalatine in OSA children treated using MTBAs. RESULTS: After the OSA children with mandibular retraction were treated with MTBAs, the maxillary intercusp width, intermolar width, anterior palate width, posterior palate width, and surface area and volume of the maxillary palate significantly increased (*P < .05). By contrast, the anterior palatal height-apex level (H3) significantly decreased (*P < .05). CONCLUSIONS: Compared with the control group, the narrow maxillary arch and basal bone were significantly enlarged after the OSA children with mandibular retraction were treated using MTBAs. The palatal surface area and volume increased, thereby allowing more space for accommodating the tongue and relieving transverse dissonance of the dentition.

5.
J Colloid Interface Sci ; 667: 321-337, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38640652

RESUMEN

Building a heterojunction is a fascinating option to guarantee sufficient carrier separation and transfer efficiency, but the mechanism of charge migration at the heterojunction interface has not been thoroughly studied. Herein, MIL-53(Fe)/Bi4O5I2 photocatalyst with a Z-scheme heterojunction structure is constructed, which achieves efficient photocatalytic decontamination under solar light. Driven by the newly-built internal electric field (IEF), the formation of Fe-O-Bi electron migration channel allows for rapid separation and transfer of charge carriers at the heterojunction interface, confirmed by the material characterization and density functional theory (DFT) calculation. The narrower band gap and improved visible light response also contribute to the enhanced photocatalytic activity of composite materials. With levofloxacin as the target pollutant, the optimal MIL-53(Fe)/Bi4O5I2 achieves complete removal of pollutant within 150 min, the photocatalysis rate of which is ca. 4.4 and 26.0 times that of pure Bi4O5I2 and MIL-53(Fe), respectively. Simultaneously, the optimal composite material exhibits satisfactory photodegradation of seven fluoroquinolones, and the photocatalysis rates are as follows: lomefloxacin > ciprofloxacin > enrofloxacin > norfloxacin > pefloxacin > levofloxacin > marbofloxacin. DFT calculations reveal a positive relationship between degradation rate and Fukui index (ƒ0) of main carbon atoms in seven fluoroquinolones. This study sheds light on the existence of electron migration channels at Z-scheme heterojunction interface to ensure sufficient photoinduced carrier transfer, and reveals the influence of pollutant structure on photolysis rate.

6.
J Am Chem Soc ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38598684

RESUMEN

Cross-coupling reactions represent an indispensable tool in chemical synthesis. An intriguing challenge in this field is to achieve selective cross-coupling between two precursors with similar reactivity or, to the limit, the identical molecules. Here we report an unexpected dehydrobrominative cross-coupling between 1,3,5-tris(2-bromophenyl)benzene molecules on silver surfaces. Using scanning tunneling microscopy, we examine the reaction process at the single-molecular level, quantify the selectivity of the dehydrobrominative cross-coupling, and reveal the modulation of selectivity by substrate lattice-related catalytic activity or molecular assembly effect. Theoretical calculations indicate that the dehydrobrominative cross-coupling proceeds via regioselective C-H bond activation of debrominated TBPB and subsequent highly selective C-C coupling of the radical-based intermediates. The reaction kinetics plays an important role in the selectivity for the cross-coupling. This work not only expands the toolbox for chemical synthesis but also provides important mechanistic insights into the selectivity of coupling reactions on the surface.

9.
World J Gastroenterol ; 30(3): 252-267, 2024 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-38314135

RESUMEN

BACKGROUND: Ulcerative colitis (UC) is an inflammatory condition with frequent relapse and recurrence. Evidence suggests the involvement of SLC6A14 in UC pathogenesis, but the central regulator remains unknown. AIM: To explore the role of SLC6A14 in UC-associated pyroptosis. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR), immunoblotting, and immunohistochemical were used to assess SLC6A14 in human UC tissues. Lipopolysaccharide (LPS) was used to induce inflammation in FHC and NCM460 cells and model enteritis, and SLC6A14 levels were assessed. Pyroptosis markers were quantified using enzyme-linked immunosorbent assay, Western blotting, and qRT-PCR, and EdU incubation, CCK-8 assays and flow cytometry were used to examine proliferation and apoptosis. Mouse models of UC were used for verification. RESULTS: SLC6A14 was increased and correlated with NLRP3 in UC tissues. LPS-induced FHC and NCM460 cells showed increased SLC6A14 levels. Reducing SLC6A14 increased cell proliferation and suppressed apoptosis. Reducing SLC6A14 decreased pyroptosis-associated proteins (ASC, IL-1ß, IL-18, NLRP3). NLRP3 overexpression counteracted the effects of sh-SLC6A14 on LPS-induced FHC and NCM460 cell pyroptosis. SLC6A14 improved the mucosa in mice with dextran sulfate sodium-induced colitis. CONCLUSION: SLC6A14 promotes UC pyroptosis by regulating NLRP3, suggesting the therapeutic potential of modulating the SLC6A14/NLRP3 axis.


Asunto(s)
Sistemas de Transporte de Aminoácidos , Colitis Ulcerosa , Colitis , Proteína con Dominio Pirina 3 de la Familia NLR , Animales , Humanos , Ratones , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Colitis Ulcerosa/inducido químicamente , Inflamasomas/metabolismo , Lipopolisacáridos , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Piroptosis
10.
Sci Rep ; 14(1): 4939, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38418479

RESUMEN

Asphalt overlay is widely used in maintaining and rehabilitating highway system performance. However, explicit calculation methods for the asphalt overlay thickness range is lacking. Taking stone mastic asphalt (SMA) and asphalt concrete (AC) asphalt overlay on cement concrete pavement as examples, the paper proposed a design method for the asphalt overlay thickness range based on the shear performance of the interlayer. Firstly, the shear stress distribution regularities on the asphalt overlay and Portland cement concrete interlayer was calculated with a multilayer elastic theory. Meanwhile, the shear strength was obtained from a series of direct shear tests. The shear characters of the asphalt overlay met with the Mohr-Coulomb criterion, and the shear strength parameters cohesive force c and interface friction angle φ on the interlayer were acquired. Finally, a method for determining the thickness range of double layer asphalt overlay under different traffic conditions was given. The epoxy resin adhesive was recommended for the highway with severe local premature shear failure compared with the modified emulsion asphalt. Therefore, through the above research, the amount of asphalt used is controlled in a reasonable range, thus improving the pavement structure durability and reducing energy consumption.

11.
BMC Pulm Med ; 24(1): 48, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38254064

RESUMEN

BACKGROUND: Noninvasive ventilation (NIV) is commonly used in patients with acute respiratory distress syndrome (ARDS). However, the incidence and distribution of treatment failure are unclear. METHODS: A comprehensive online search was conducted to select potentially eligible studies with reports of the rate of NIV failure in patients with ARDS. A manual search was also performed to identify additional studies. Data were extracted to calculate the pooled incidences of NIV failure and mortality. Based on oxygenation, the severity of the disease was classified as mild, moderate, or severe ARDS. Based on etiologies, ARDS was defined as being of pulmonary origin or extrapulmonary origin. RESULTS: We enrolled 90 studies in this meta-analysis, involving 98 study arms. The pooled incidence of NIV failure was 48% (n = 5847, 95% confidence interval [CI]: 43-52%). The pooled incidence of ICU mortality was 29% (n = 2363, 95%CI: 22-36%), and that of hospital mortality was 33% (n = 2927, 95%CI: 27-40%). In patients with mild, moderate, and severe ARDS, the pooled incidence of NIV failure was 30% (n = 819, 95%CI: 21-39%), 51% (n = 1332, 95%CI: 43-60%), and 71% (n = 525, 95%CI: 62-79%), respectively. In patients with pulmonary ARDS, it was 45% (n = 2687, 95%CI: 39-51%). However, it was 30% (n = 802, 95%CI: 21-38%) in those with extrapulmonary ARDS. In patients with immunosuppression, the incidence of NIV failure was 62% (n = 806, 95%CI: 50-74%). However, it was 46% (n = 5041, 95%CI: 41-50%) in those without immunosuppression. CONCLUSIONS: Nearly half of patients with ARDS experience NIV failure. The incidence of NIV failure increases with increasing ARDS severity. Pulmonary ARDS seems to have a higher rate of NIV failure than extrapulmonary ARDS. ARDS patients with immunosuppression have the highest rate of NIV failure.


Asunto(s)
Ventilación no Invasiva , Síndrome de Dificultad Respiratoria , Humanos , Incidencia , Síndrome de Dificultad Respiratoria/epidemiología , Síndrome de Dificultad Respiratoria/terapia , Mortalidad Hospitalaria , Terapia de Inmunosupresión
12.
Artículo en Inglés | MEDLINE | ID: mdl-38194184

RESUMEN

This study presents a comparison between two hydrolysis systems (MnO2/H2O2 and ascorbic acid (VC)/H2O2) for the depolymerization of exopolysaccharide (EPS) from Lactobacillus plantarum LPC-1. Response surface methodology (RSM) was used to optimize these two degradation systems, resulting in two H2O2-free degradation products, MEPS (MnO2/H2O2-treated EPS) and VEPS (VC/H2O2-treated EPS), where H2O2 residues in the final products and their antioxidant activity were considered vital points. The relationship between the structural variations of two degraded polysaccharides and their antioxidant activity was characterized. Physicochemical tests showed that H2O2 had a notable impact on determining the total and reducing sugars in the polysaccharides, and both degradation systems efficiently eliminated this effect. After optimization, the average molecular weight of EPS was reduced from 265.75 kDa to 135.41 kDa (MEPS) and 113.11 kDa (VEPS), improving its antioxidant properties. Characterization results showed that the two hydrolysis products had similar major functional groups and monosaccharide composition as EPS. The crystal structure, main chain length, and branched chain number were crucial factors affecting the biological activity of polysaccharides. In pot testing, two degraded polysaccharides improved spinach quality more than EPS due to their lower molecular weights, suggesting the advantages of low-molecular-weight polysaccharides. In summary, these two degradation techniques offer valuable insights for further expanding the utilization of microbial resources.

13.
SSM Popul Health ; 25: 101605, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38292049

RESUMEN

Objective: This research aims to construct and authenticate a comprehensive predictive model for all-cause mortality, based on a multifaceted array of risk factors. Methods: The derivation cohort for this study was the Chinese Longitudinal Healthy Longevity Survey (CLHLS), while the Healthy Ageing and Biomarkers Cohort Study (HABCS) and the China Health and Retirement Longitudinal Study (CHARLS) were used as validation cohorts. Risk factors were filtered using lasso regression, and predictive factors were determined using net reclassification improvement. Cox proportional hazards models were employed to establish the mortality risk prediction equations, and the model's fit was evaluated using a discrimination concordance index (C-index). To evaluate the internal consistency of discrimination and calibration, a 10x10 cross-validation technique was employed. Calibration plots were generated to compare predicted probabilities with observed probabilities. The prediction ability of the equations was demonstrated using nomogram. Results: The CLHLS (mean age 88.08, n = 37074) recorded 28158 deaths (179683 person-years) throughout the course of an 8-20 year follow-up period. Additionally, there were 1384 deaths in the HABCS (mean age 86.74, n = 2552), and 1221 deaths in the CHARLS (mean age 72.48, n = 4794). The final all-cause mortality model incorporated demographic characteristics like age, sex, and current marital status, as well as functional status indicators including cognitive function and activities of daily living. Additionally, lifestyle factors like past smoking condition and leisure activities including housework, television viewing or radio listening, and gardening work were included. The C-index for the derivation cohort was 0.728 (95% CI: 0.724-0.732), while the external validation results for the CHARS and HABCS cohorts were 0.761 (95% CI: 0.749-0.773) and 0.713 (95% CI: 0.697-0.729), respectively. Conclusion: This study introduces a reliable, validated, and acceptable mortality risk predictor for older adults in China. These predictive factors have potential applications in public health policy and clinical practice.

14.
J Colloid Interface Sci ; 660: 800-809, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38277837

RESUMEN

Electrocatalytic hydrogenation (ECH) reduction provides an environment-friendly alternative to conventional method for the upgrade of furfural to furfuryl alcohol. At present, exploring superior catalysts with high activity and selectivity, figuring out the reduction mechanism in aqueous alkaline environment are urgent. In this work, zinc cobalt bimetallic oxide (ZnMn2O4) with surface-derived Zn2+ vacancies supported by carbon nanofibers (d-ZnMn2O4-C) was fabricated. The d-ZnMn2O4-C exhibited excellent performance in electrocatalytic reduction of furfural, high furfuryl alcohol yield (49461.1 ± 228 µmol g-1) and Faradaic efficiency (95.5 ± 0.5 %) was obtained. In-depth research suggested that carbon nanofiber may strongly promoted the production of adsorbed hydrogen (Hads), and Zn2+ vacancies may significantly lowered the energy barrier of furfural reduction to furfuryl alcohol, the synergistic effect between carbon nanofiber and d-ZnMn2O4 probably facilitated the reaction between Hads and furfuryl alcohol radical, thereby promoting the formation of furfuryl alcohol. Furthermore, the reaction mechanism was clarified by inhibitor coating and isotope experiments, the results of which revealed that the conversion of furfural to furfuryl alcohol on d-ZnMn2O4-C followed both ECH and direct electroreduction mechanism.

16.
Cytokine ; 174: 156469, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38101168

RESUMEN

BACKGROUND: Developmental delay (DD) occurs when children fail to reach developmental milestones in comparison to peers of the same age range. However, there are no valuable biomarkers for the early diagnosis of DD. Since there is no specific marker for screening the disease, we evaluated plasma NSE, TNF-α and sIL2-Rα as potential markers for this purpose. METHODS: In this cross-sectional randomized case-control study, a total of 174 DD patients and 49 matched elderly controls aged between 2 months and 60 months were recruited. A sensitive enzyme-linked immunosorbent assay and an immunoradiometric assay were used to evaluate the levels of plasma IL-1, IL-6, IL-8, IL-10, sIL2-Rα, TNF-α, and NSE. Statistical analyses using t test, χ2, ANOVA, ROC curves and binary logistic regression models were performed. RESULTS: In comparison to the control group, the DD group had greater levels of NSE, TNF-α, and sIL2-Rα(p < 0.05). In the binary logistic regression analysis of DD, NSE had an odds ratio (OR) of 1.783 (95 % CI 1.297 to 2.451, p = 0.000), indicating that NSE was an independent risk factor for DD. The plasma TNF-α level was positively correlated with plasma NSE and sIL2-Rα levels in the DD group (r = 0.366 and 0.433, respectively), and the DQ score and plasma sIL2-Rα level in the DD group were positively correlated. The ROC curve revealed that the respective areas under the NSE, TNF-α, and sIL2-Rα ROC curves were 0.9797, 0.9365, and 0.8533, respectively. Moreover, a significant increase in AUC was observed using combined ROC curve analysis. CONCLUSIONS: Children with DD have significantly altered plasma concentrations of sIL2-Rα, NSE, and TNF-α. NSE, TNF-α and sIL2-Rα can be used as DD blood biomarkers. This information may be helpful in early diagnosis and intervention.


Asunto(s)
Fosfopiruvato Hidratasa , Factor de Necrosis Tumoral alfa , Anciano , Niño , Humanos , Lactante , Curva ROC , Estudios de Casos y Controles , Estudios Transversales , Subunidad alfa del Receptor de Interleucina-2 , Biomarcadores
17.
Opt Lett ; 48(24): 6496-6499, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38099782

RESUMEN

Reflective dynamic focusing devices (RDFDs) have shown their potential in laser scanning as high-performance laser Z-direction focusing devices. However, the scanning range of RDFD-based scanners is limited by aberrations during dynamic focusing. An aspheric symmetry correction (ASC) method was proposed to extend the effective scanning range. An aspheric lens was introduced to correct the optical path difference (OPD) and optimize aberrations. As a result, the scanning range in the three-dimensional (3D) space increased by 15.2%. The ASC method has been proven to extend the 3D scanning range of RDFD-based scanners and may have broad application prospects.

18.
BMC Genomics ; 24(1): 786, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110864

RESUMEN

BACKGROUND: Cymbidium sinense is an orchid that is typically used as a potted plant, given its high-grade ornamental characteristics, and is most frequently distributed in China and SE Asia. The inability to strictly regulate flowering in this economically important potted and cut-flower orchid is a bottleneck that limits its industrial development. Studies on C. sinense flowering time genes would help to elucidate the mechanism regulating flowering. There are very few studies on the genetic regulation of flowering pathways in C. sinense. Photoperiod significantly affects the flowering of C. sinense, but it was unknown how the CONSTANS gene family is involved in regulating flowering. RESULTS: In this study, eight CONSTANS-like genes were identified and cloned. They were divided into three groups based on a phylogenetic analysis. Five representative CsCOL genes (CsCOL3/4/6/8/9) were selected from the three groups to perform expression characterization and functional study. CsCOL3/4/6/8/9 are nucleus-localized proteins, and all five CsCOL genes were expressed in all organs, mainly in leaves followed by sepals. The expression levels of CsCOL3/4 (group I) were higher in all organs than other CsCOL genes. Developmental stage specific expression revealed that the expression of CsCOL3/4/9 peaked at the initial flowering stage. In contrast, the transcript level of CsCOL6/8 was highest at the pedicel development stage. Photoperiodic experiments demonstrated that the transcripts of the five CsCOL genes exhibited distinct diurnal rhythms. Under LD conditions, the overexpression of CsCOL3/4 promoted early flowering, and CsCOL6 had little effect on flowering time, whereas CsCOL8 delayed flowering of Arabidopsis thaliana. However, under SD conditions, overexpression of CsCOL4/6/8 promoted early flowering and the rosette leaves growth, and CsCOL3 induced flower bud formation in transgenic Arabidopsis. CONCLUSION: The phylogenetic analysis, temporal and spatial expression patterns, photoperiodic rhythms and functional study indicate that CsCOL family members in C. sinense were involved in growth, development and flowering regulation through different photoperiodic pathway. The results will be useful for future research on mechanisms pertaining to photoperiod-dependent flowering, and will also facilitate genetic engineering-based research that uses Cymbidium flowering time genes.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Filogenia , Fotoperiodo , Ritmo Circadiano , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Flores , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Unión al ADN/genética , Factores de Transcripción/metabolismo
19.
Sci Rep ; 13(1): 21122, 2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38036691

RESUMEN

Stropharia rugosoannulata is a well-renowned edible mushroom due to its nutritional and nutraceutical properties. This article focuses on the study of stipe cracking in S. rugosoannulata, a common issue in outdoor cultivation of this mushroom in South China. The findings reveal that the stipe cracks of S. rugosoannulata are primarily horizontal (transverse). Typically, cracks appear between the annulus and the middle part of the stipe prior to the opening of the pileus. Following the opening of the pileus, a fresh crack appears on the upper part of the stipe above the annulus. During the growth of S. rugosoannulata, two distinct elongation sections are observed in the stipe, separated by the annulus. The location of cracks coincides with these elongation sections, and the sequence of crack occurrences matches with the sequence of these elongation sections. The frequency of stipe cracking varies according to developmental stages and humidity conditions. The conclusion of this study is that S. rugosoannulata stipes crack during elongation and within elongation sections when humidity is low (≤ 60%), with the S3 developmental stage having the highest risk of cracking.


Asunto(s)
Agaricales , Vino , Humedad , China
20.
Int J Biol Macromol ; 253(Pt 2): 126789, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37690636

RESUMEN

Selenium nanoparticles (SeNPs) have gained significant attention in the agricultural field due to their favorable bioavailability and low toxicity, making them a highly researched subject. In this study, crude polysaccharides from spent mushroom substrate of Agrocybe aegerita (AaPs) were extracted for preparing the polysaccharide­selenium-nanoparticles (AaPs-SeNPs) by ascorbic acid reduction method. The structure of AaPs-SeNPs was analyzed and their growth-promoting effects on rice seedlings were studied by adopting different application methods. The results revealed that AaPs-SeNPs exhibited improved free radical scavenging ability, with a lower half-maximal inhibitory concentrations compared to AaPs. Rice seedlings treated with AaPs-SeNPs showed significant enhancements in growth characteristics when compared to AaPs treatment, and foliar application exhibited a better growth-promoting effect compared to root application. Moreover, the growth performance and antioxidant enzyme activities of rice seedlings were enhanced by the addition of AaPs-SeNPs, and the absorption efficiency of essential nutrients such as N/P/K and Fe/Zn/Mn was also improved at appropriate concentrations, which could be one of the key factors contributing to the improved growth performance of plants. This study provides new aspects for the utilization of SMS, and also offers new insights from the perspective of nutrient absorption on how polysaccharide-conjugated selenium nanoparticles enhance crop growth.


Asunto(s)
Agaricales , Nanopartículas , Oryza , Selenio , Selenio/química , Plantones , Polisacáridos/farmacología , Polisacáridos/química , Antioxidantes/farmacología , Antioxidantes/química , Nanopartículas/química
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