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1.
Nature ; 628(8007): 313-319, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38570689

RESUMEN

Transition metal tellurides (TMTs) have been ideal materials for exploring exotic properties in condensed-matter physics, chemistry and materials science1-3. Although TMT nanosheets have been produced by top-down exfoliation, their scale is below the gram level and requires a long processing time, restricting their effective application from laboratory to market4-8. We report the fast and scalable synthesis of a wide variety of MTe2 (M = Nb, Mo, W, Ta, Ti) nanosheets by the solid lithiation of bulk MTe2 within 10 min and their subsequent hydrolysis within seconds. Using NbTe2 as a representative, we produced more than a hundred grams (108 g) of NbTe2 nanosheets with 3.2 nm mean thickness, 6.2 µm mean lateral size and a high yield (>80%). Several interesting quantum phenomena, such as quantum oscillations and giant magnetoresistance, were observed that are generally restricted to highly crystalline MTe2 nanosheets. The TMT nanosheets also perform well as electrocatalysts for lithium-oxygen batteries and electrodes for microsupercapacitors (MSCs). Moreover, this synthesis method is efficient for preparing alloyed telluride, selenide and sulfide nanosheets. Our work opens new opportunities for the universal and scalable synthesis of TMT nanosheets for exploring new quantum phenomena, potential applications and commercialization.

2.
Plant Cell ; 34(12): 4778-4794, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-35976113

RESUMEN

Glycosylphosphatidylinositol (GPI) anchoring is a common protein modification that targets proteins to the plasma membrane (PM). Knowledge about the GPI lipid tail, which guides the secretion of GPI-anchored proteins (GPI-APs), is limited in plants. Here, we report that rice (Oryza sativa) BRITTLE CULM16 (BC16), a membrane-bound O-acyltransferase (MBOAT) remodels GPI lipid tails and governs cell wall biomechanics. The bc16 mutant exhibits fragile internodes, resulting from reduced cell wall thickness and cellulose content. BC16 is the only MBOAT in rice and is located in the endoplasmic reticulum and Golgi apparatus. Yeast gup1Δ mutant restoring assay and GPI lipid composition analysis demonstrated BC16 as a GPI lipid remodelase. Loss of BC16 alters GPI lipid structure and disturbs the targeting of BC1, a GPI-AP for cellulose biosynthesis, to the PM lipid nanodomains. Atomic force microscopy revealed compromised deposition of cellulosic nanofibers in bc16, leading to an increased Young's modulus and abnormal mechanical properties. Therefore, BC16-mediated lipid remodeling directs the GPI-APs, such as BC1, to the cell surface to fulfill multiple functions, including cellulose organization. Our work unravels a mechanism by which GPI lipids are remodeled in plants and provides insights into the control of cell wall biomechanics, offering a tool for breeding elite crops with improved support strength.


Asunto(s)
Glicosilfosfatidilinositoles , Aparato de Golgi , Glicosilfosfatidilinositoles/metabolismo , Aparato de Golgi/metabolismo , Membrana Celular/metabolismo , Saccharomyces cerevisiae/metabolismo , Aciltransferasas/metabolismo , Pared Celular/metabolismo , Celulosa/metabolismo
3.
BMC Plant Biol ; 24(1): 389, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38730341

RESUMEN

BACKGROUND: Kobreisa littledalei, belonging to the Cyperaceae family is the first Kobresia species with a reference genome and the most dominant species in Qinghai-Tibet Plateau alpine meadows. It has several resistance genes which could be used to breed improved crop varieties. Reverse Transcription Quantitative Real-Time Polymerase Chain Reaction (RT-qPCR) is a popular and accurate gene expression analysis method. Its reliability depends on the expression levels of reference genes, which vary by species, tissues and environments. However, K.littledalei lacks a stable and normalized reference gene for RT-qPCR analysis. RESULTS: The stability of 13 potential reference genes was tested and the stable reference genes were selected for RT-qPCR normalization for the expression analysis in the different tissues of K. littledalei under two abiotic stresses (salt and drought) and two hormonal treatments (abscisic acid (ABA) and gibberellin (GA)). Five algorithms were used to assess the stability of putative reference genes. The results showed a variation amongst the methods, and the same reference genes showed tissue expression differences under the same conditions. The stability of combining two reference genes was better than a single one. The expression levels of ACTIN were stable in leaves and stems under normal conditions, in leaves under drought stress and in roots under ABA treatment. The expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression was stable in the roots under the control conditions and salt stress and in stems exposed to drought stress. Expression levels of superoxide dismutase (SOD) were stable in stems of ABA-treated plants and in the roots under drought stress. Moreover, RPL6 expression was stable in the leaves and stems under salt stress and in the stems of the GA-treated plants. EF1-alpha expression was stable in leaves under ABA and GA treatments. The expression levels of 28 S were stable in the roots under GA treatment. In general, ACTIN and GAPDH could be employed as housekeeping genes for K. littledalei under different treatments. CONCLUSION: This study identified the best RT-qPCR reference genes for different K. littledalei tissues under five experimental conditions. ACTIN and GAPDH genes can be employed as the ideal housekeeping genes for expression analysis under different conditions. This is the first study to investigate the stable reference genes for normalized gene expression analysis of K. littledalei under different conditions. The results could aid molecular biology and gene function research on Kobresia and other related species.


Asunto(s)
Genes de Plantas , Reacción en Cadena en Tiempo Real de la Polimerasa , Plantones , Plantones/genética , Cyperaceae/genética , Estándares de Referencia , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico/genética , Sequías , Reproducibilidad de los Resultados , Ácido Abscísico/metabolismo , Giberelinas/metabolismo
4.
Small ; 20(28): e2308646, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38334202

RESUMEN

An immune reaction known as inflammation serves as a shield from external danger signals, but an overactive immune system may additionally lead to tissue damage and even a variety of inflammatory disorders. By inheriting biological functionalities and serving as both a therapeutic medication and a drug carrier, cell membrane-based nanotherapeutics offer the potential to treat inflammatory disorders. To further strengthen the anti-inflammatory benefits of natural cell membranes, researchers alter and optimize the membranes using engineering methods. This review focuses on engineered cell membrane-based nanotherapeutics (ECMNs) and their application in treating inflammation-related diseases. Specifically, this article discusses the methods of engineering cell membranes for inflammatory diseases and examines the progress of ECMNs in inflammation-targeted therapy, inflammation-neutralizing therapy, and inflammation-immunomodulatory therapy. Additionally, the article looks into the perspectives and challenges of ECMNs in inflammatory treatment and offers suggestions as well as guidance to encourage further investigations and implementations in this area.


Asunto(s)
Membrana Celular , Inflamación , Humanos , Membrana Celular/metabolismo , Animales , Nanopartículas/química , Nanomedicina/métodos
5.
Chemistry ; 30(24): e202304200, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38340042

RESUMEN

Regulation of fluorescence and self-assembly of a salicylaldehyde azine-containing amphiphile by a water-soluble pillar[5]arene via host-guest recognition in water was realized. The fluorescence and the self-assembled aggregates of the bola-type amphiphile G can be tailored by adding different amounts of water-soluble pillar[5]arene (WP5). In addition, the emission property and self-assembly behavior of G and WP5 are responsive to pH conditions. Furthermore, the fluorescence emission property of G and the regulation by WP5 or pH conditions was applied as information encryption material, rewritable paper, and erasable ink. We believe that this fluorescence regulation strategy is promising for the construction of advanced fluorescent organic materials.

6.
Cell Biol Toxicol ; 40(1): 59, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39060559

RESUMEN

Acute liver injury (ALI) is a common life-threatening condition with a high mortality rate due to liver disease-related death. However, current therapeutic interventions for ALI remain ineffective, and the development of effective novel therapies is urgently needed. Liver samples from patients with drug-induced ALI were collected to detect adenosine kinase (ADK) expression. Male C57BL/6 J mice, hepatocyte-specific ADK knockout (ADKHKO) mice, and their controls (ADKf/f) were exposed to acetaminophen (APAP) and other treatments to investigate the mechanisms of APAP-related ALI. ADK expression was significantly decreased in APAP-injured livers. Hepatocyte-specific ADK deficiency exacerbated APAP-induced ALI, while a gain-of-function approach delivering AAV-ADK, markedly alleviated APAP-induced ALI, as indicated by changes in alanine aminotransferases (ALT) levels, aspartate aminotransferase (AST) levels, neutrophil infiltration and hepatocyte death. This study showed that ADK played a critical role in ALI by activating autophagy through two signaling pathways, the adenosine monophosphate-activated protein kinase (AMPK)-mTOR pathway and the adenosine receptor A1 (ADORA1)-Akt-mTOR pathway. Furthermore, we found that metformin upregulated ADK expression in hepatocytes and protected against APAP-induced ALI. These results demonstrate that ADK is critical in protecting against APAP-induced ALI and that developing therapeutics targeting ADK-adenosine-ADORA1 is a new approach for ALI treatment. Metformin is a potential candidate for preventing ALI by upregulating ADK.


Asunto(s)
Acetaminofén , Adenosina Quinasa , Autofagia , Enfermedad Hepática Inducida por Sustancias y Drogas , Hepatocitos , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Acetaminofén/efectos adversos , Adenosina Quinasa/metabolismo , Adenosina Quinasa/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Hepatocitos/metabolismo , Hepatocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
7.
Acta Pharmacol Sin ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39152295

RESUMEN

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder characterized by cognitive impairments. Despite the limited efficacy of current treatments for AD, the 1,2,4-oxadiazole structure has garnered significant attention in medicinal chemistry due to its potential impact on mGluR1 and its association with AD therapy. In this study, a series of novel 1,2,4-oxadiazole derivatives were designed, synthesized, and evaluated for the neuroprotective effects in human neuroblastoma (SH-SY5Y) cells. Among all the derivatives tested, FO-4-15 (5f) existed the lowest cytotoxicity and the highest protective effect against H2O2. Based on these in vitro results, FO-4-15 was administered to 3×Tg mice and significantly improved the cognitive impairments of the AD mice. Pathological analysis showed that FO-4-15 significantly reduced Aß accumulation, Tau hyper-phosphorylation, and synaptic impairments in the 3×Tg mice. Dysfunction of the CaMKIIα/Fos signaling pathway in 3×Tg mice was found to be restored by FO-4-15 and the necessity of the CaMKIIα/Fos for FO-4-15 was subsequently confirmed by the use of a CaMKIIα inhibitor in vitro. Beyond that, mGluR1 was identified to be a potential target of FO-4-15, and the interaction of FO-4-15 and mGluR1 was displayed by Ca2+ flow increase, molecular docking, and interaction energy analysis. The target of FO-4-15 was further confirmed in vitro by JNJ16259685, a nonselective inhibitor of mGluR1. These findings suggest that FO-4-15 may hold promise as a potential treatment for Alzheimer's disease.

8.
Sensors (Basel) ; 23(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37448073

RESUMEN

The direction of human gaze is an important indicator of human behavior, reflecting the level of attention and cognitive state towards various visual stimuli in the environment. Convolutional neural networks have achieved good performance in gaze estimation tasks, but their global modeling capability is limited, making it difficult to further improve prediction performance. In recent years, transformer models have been introduced for gaze estimation and have achieved state-of-the-art performance. However, their slicing-and-mapping mechanism for processing local image patches can compromise local spatial information. Moreover, the single down-sampling rate and fixed-size tokens are not suitable for multiscale feature learning in gaze estimation tasks. To overcome these limitations, this study introduces a Swin Transformer for gaze estimation and designs two network architectures: a pure Swin Transformer gaze estimation model (SwinT-GE) and a hybrid gaze estimation model that combines convolutional structures with SwinT-GE (Res-Swin-GE). SwinT-GE uses the tiny version of the Swin Transformer for gaze estimation. Res-Swin-GE replaces the slicing-and-mapping mechanism of SwinT-GE with convolutional structures. Experimental results demonstrate that Res-Swin-GE significantly outperforms SwinT-GE, exhibiting strong competitiveness on the MpiiFaceGaze dataset and achieving a 7.5% performance improvement over existing state-of-the-art methods on the Eyediap dataset.


Asunto(s)
Suministros de Energía Eléctrica , Aprendizaje , Humanos , Redes Neurales de la Computación
9.
Small ; 18(5): e2104506, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34837671

RESUMEN

Pursuing high areal energy density and developing scalable fabrication strategies of micro-batteries are the key for the progressive printed microelectronics. Herein, the scalable fabrication of multi-layer printable lithium ion micro-batteries (LIMBs) with ultrahigh areal energy density and exceptional flexibility is reported, based on highly conductive and mechanically stable inks by fully incorporating the polyurethane binders in dibasic esters with high-conducting additives of graphene and carbon nanotubes into active materials to construct a cross-linked conductive network. Benefiting from relatively higher electrical conductivity (≈7000 mS cm-1 ) and stably connected network of microelectrodes, the as-fabricated LIMBs by multi-layer printing display robust areal capacity of 398 µAh cm-2 , and remarkable areal energy density of 695 µWh cm-2 , which are much higher than most LIMBs reported. Further, the printed LIMBs show notable capacity retention of 88% after 3000 cycles, and outstanding flexibility without any structure degradation under various torsion states and folding angles. Importantly, a wearable smart bracelet, composed of a serially connected LIMBs pack, a temperature sensor, and a light-emitting diode, is realized for the automatic detection of body temperature. Therefore, this strategy of fabricating highly conductive and mechanically stable printable ink will open a new avenue for developing high-performance printable LIMBs for smart microelectronics.


Asunto(s)
Nanotubos de Carbono , Dispositivos Electrónicos Vestibles , Electrónica , Tinta , Litio/química , Nanotubos de Carbono/química
10.
Nanotechnology ; 33(7)2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34727538

RESUMEN

Achieving an efficient and inexpensive bactericidal effect is a key point for the design of antibacterial agent. Recent advances have proved molybdenum disulfide (MoS2) as a promising platform for antimicrobial applications, while the combination of metal nanoparticle would promote the antibacterial efficiency. Nevertheless, the dispersivity, cheapness and safety of metal nanoparticle loaded on MoS2raised some concerns. In this paper, we successfully realized a uniform decoration of copper nanoparticles (CuNPs) on surface of MoS2nanosheets, and the size of CuNPs could be controlled below 5 nm. Under 5 min irradiation of 660 nm visible light, the synthesized CuNPs/MoS2composite demonstrated superior antibacterial performances (almost 100% bacterial killed) towards both Gram-negativeE. coliand Gram-positiveS. aureusover the single component (Cu or MoS2), while the bactericidal effect could last for at least 6 h. The synergism of photodynamic generated hydroxyl radical (·OH), oxidative stress without reactive oxygen species production and the release of Cu ions was considered as the mechanism for the antibacterial properties of CuNPs/MoS2. Our findings provided new insights into the development of two-dimensional antibacterial nanomaterials of high cost performance.


Asunto(s)
Antibacterianos , Bacterias/efectos de los fármacos , Cobre , Disulfuros , Nanopartículas del Metal , Molibdeno , Antibacterianos/química , Antibacterianos/farmacocinética , Antibacterianos/farmacología , Antibacterianos/efectos de la radiación , Cobre/química , Cobre/farmacocinética , Cobre/farmacología , Cobre/efectos de la radiación , Disulfuros/química , Disulfuros/farmacología , Disulfuros/efectos de la radiación , Luz , Nanopartículas del Metal/química , Nanopartículas del Metal/efectos de la radiación , Molibdeno/química , Molibdeno/farmacología , Molibdeno/efectos de la radiación , Estrés Oxidativo/efectos de los fármacos , Tamaño de la Partícula , Procesos Fotoquímicos
11.
Front Public Health ; 12: 1435162, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39114522

RESUMEN

Purpose: The objective of this study is to gain a more nuanced understanding of the specific impact of income inequality on the utilization of healthcare services for older adults. Additionally, the study aims to elucidate the moderating and mediating roles of public transfer income and psychological health in this context. Methods: A systematic examination of the impact of income inequality on healthcare utilization among older adults was conducted through field questionnaire surveys in six cities across three major geographical regions (West, Central, and East). The analysis employed baseline regression, as well as mediating and moderating effect tests. Results: First, there is a negative relationship between income inequality and the use of therapeutic healthcare services (ß1 = -0.484, P < 0.01) and preventive healthcare services (ß2 = -0.576, P < 0.01) by older adults. This relationship is more pronounced in the low- and medium-income groups as well as in the western region. The mediating effect of psychological state is significant (ß3 = -0.331, P < 0.05, ß4 = -0.331, P < 0.05). Public transfer income plays a significant role in regulation. The moderating effect of public transfer income on therapeutic services was more significant in low-income groups (ß5 = 0.821, P < 0.01). The moderating effect of public transfer income on preventive services was more significant in middle-income groups (ß6 = 0.833, P < 0.01). Conclusion: The study clearly demonstrates a significant negative correlation between income inequality and the utilization of healthcare services by older adults. Furthermore, the study reveals that this relationship is particularly pronounced among older adults in low- and medium-income and Western regions. This detailed analysis of regional and income level heterogeneity is of particular value in this field of research. Secondly, this study attempts to integrate the two pivotal dimensions of public transfer income and psychological state for the first time, elucidating their moderating and mediating roles in this relationship. The findings indicate that public transfer income serves as a moderating factor, exerting a notable "reordering effect" on income inequality and resulting in a "deprivation effect." Such factors may impede the utilization of medical services, potentially influencing the psychological state of older adults.


Asunto(s)
Renta , Aceptación de la Atención de Salud , Humanos , China , Anciano , Femenino , Masculino , Renta/estadística & datos numéricos , Encuestas y Cuestionarios , Aceptación de la Atención de Salud/estadística & datos numéricos , Factores Socioeconómicos , Persona de Mediana Edad , Ciudades/estadística & datos numéricos , Anciano de 80 o más Años , Disparidades en Atención de Salud/estadística & datos numéricos
12.
Environ Pollut ; 345: 123560, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38355080

RESUMEN

Although growing evidences have proved the wide presence of organophosphate esters (OPEs) in marine environments, information on the tissue- and species-specific accumulation characteristics of these emerging pollutants in wild marine fish and the associated human exposure risks are currently lacking. Eleven OPEs were comprehensively investigated for their occurrence and tissue accumulation in 15 marine fish species and their living environment matrices (seawater and sediment) from the Beibu Gulf. The OPE concentrations were statistically higher in the liver (17.6-177 ng/g ww, mean 90.9 ± 52.1 ng/g ww) than those of muscle tissues (2.04-22.9 ng/g ww, mean 10.6 ± 5.6 ng/g ww). Tris (phenyl) phosphate (TPHP) was the most predominant OPE congeners in fish liver, and tris(2-chloropropyl) phosphate (TCIPP) and tris(2-chloroethyl) phosphate (TCEP) were dominant OPEs in the muscle. The results suggested different OPE profiles occurred between the tissues. The median logarithmic bioaccumulation factors (BAFs) of TPHP in the muscle and liver, and TCEP in muscle were higher than the regulatory benchmark value (BCF >3.7), indicating very strong bioaccumulation. Carnivorous benthic fish appear to potentially accumulate TPHP, while pelagic and omnivory fish tend to accumulate TCIPP and TCEP. Except for proteins and phospholipids, no significant relationships were found between OPE levels and other biological properties of the studied fish. The results implied that the species-specific accumulation of OPEs mainly attributed to habitat and feeding habit rather than the difference of biochemical composition among species. Metabolism may have a significant effect on the bioaccumulation of OPEs in marine fish. The dietary risks of OPEs for consumers in different age groups ranged from 2.02 × 10-4 to 3.01 × 10-3, indicating relatively low human exposure risks from fish consumption.


Asunto(s)
Ésteres , Retardadores de Llama , Fosfinas , Animales , Humanos , Bioacumulación , Organofosfatos/metabolismo , Fosfatos , China , Monitoreo del Ambiente , Retardadores de Llama/análisis
13.
Fundam Res ; 4(2): 307-314, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38933500

RESUMEN

Two-dimensional MXenes are key high-capacitance electrode materials for micro-supercapacitors (MSCs) catering to integrated microsystems. However, the narrow electrochemical voltage windows of conventional aqueous electrolytes (≤ 1.23 V) and symmetric MXene MSCs (typically ≤ 0.6 V) substantially limit their output voltage and energy density. Highly concentrated aqueous electrolytes exhibit lower water molecule activity, which inhibits water splitting and consequently widens the operating voltage window. Herein, we report ultrahigh-voltage aqueous planar asymmetric MSCs (AMSCs) based on a highly concentrated LiCl-gel quasi-solid-state electrolyte with MXene (Ti3C2T x ) as the negative electrode and MnO2 nanosheets as the positive electrode (MXene//MnO2-AMSCs). The MXene//MnO2-AMSCs exhibit a high voltage of up to 2.4 V, attaining an ultrahigh volumetric energy density of 53 mWh cm-3. Furthermore, the in-plane geometry and the quasi-solid-state electrolyte enabled excellent mechanical flexibility and performance uniformity in the serially/parallel connected packs of our AMSCs. Notably, the MXene//MnO2-AMSC-based integrated microsystem, in conjunction with solar cells and consumer electronics, could efficiently realize simultaneous energy harvesting, storage, and conversion. The findings of this study provide insights for constructing high-voltage aqueous MXene-based AMSCs as safe and self-sufficient micropower sources in smart integrated microsystems.

14.
Body Image ; 51: 101766, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38986235

RESUMEN

The Body Talk Scale (BTS) measures both negative body talk (including fat talk and muscle talk) and positive body talk across genders. In this study, we translated it into Chinese and assessed its structure, reliability and validity among mainland Chinese residents. Item analyses indicated that no item deletion was necessary for this study, and both exploratory factor analysis (n = 1853) and exploratory graph analysis (n = 1583) supported the three-factor structure of the original scale. Confirmatory factor analysis showed that the scale had a good model fit with CFI= 0.95, GFI= 0.93, TLI= 0.94, and RMSEA= 0.079(90 %CI [0.075, 0.084]). The results also showed that the Chinese version of the BTS had adequate criterion-related validity,internal consistency and six-week test-retest reliability. Meanwhile, the scale has good measurement invariance with respect to gender and can be tested for gender differences. In conclusion, the BTS showed sufficient psychometric properties in a Chinese sample, making it a valid instrument for studying body talk and health status in Chinese populations.

15.
Sci Total Environ ; 927: 172006, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38554978

RESUMEN

Grasslands account for approximately one-third of the global terrestrial carbon stocks. However, a limited understanding of the impact of grazing exclusion on carbon storage in grassland ecosystems hinders progress towards restoring overgrazed grasslands and promoting carbon sequestration. In this study, we conducted a comprehensive meta-analysis to investigate the effects of grazing exclusion on aboveground biomass (AGB) and soil organic carbon (SOC) in four grasslands: alpine grasslands (AP), tropical savannas (TS), temperate subhumid grasslands (TG), and a semi-desert steppe (SD). Our meta-analysis indicated that grazing exclusion significantly enhanced carbon sequestration in grassland ecosystems, and the benefits of carbon sequestration were most pronounced in the AP, followed by the TG, SD, and TS. Grazing exclusion duration (DUR) was a significant factor associated with the response of aboveground biomass (AGB) and soil organic carbon (SOC) to grazing exclusion. Moreover, the relationships between AGB and DUR were nonlinear, with existence thresholds of 18, 21, 12, 19, and 23 years in global grasslands (ALL), AP, TS, TG, and SD, respectively. However, the relationship between SOC and DUR was linear, with SOC continuing to increase as DUR increased (up to 40 years). The multi-objective optimization indicated that the optimal duration of grazing exclusion for grassland carbon sequestration was 18-20, 21-23, 12-14, 19-21, and 23-25 years for ALL, AP, TS, TG, and SD, respectively. Our study contributes to the enhancement of grazing management and offers better options for increasing carbon sequestration in grasslands.


Asunto(s)
Biomasa , Secuestro de Carbono , Carbono , Pradera , Suelo , Suelo/química , Carbono/análisis , Herbivoria , Animales
16.
Water Res ; 261: 122043, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38981351

RESUMEN

The bioaccumulation and trophic transfer of organophosphate flame retardants (OPFRs) in marine ecosystems have attracted great attention in recent research, but our understanding of the trophic transfer mechanisms involved is limited. In this study, we investigated the trophodynamics of OPFRs and their metabolites in a subtropical coastal food web collected from the northern Beibu Gulf, China, and characterized their trophodynamics using fugacity- and biotransformation-based approaches. Eleven OPFRs and all seven metabolites were simultaneously quantified in the shellfish, crustacean, pelagic fish, and benthic fish samples, with total concentrations ranging from 164 to 4.11 × 104 and 4.56-4.28 × 103 ng/g lipid weight, respectively. Significant biomagnification was observed only for tris (phenyl) phosphate (TPHP) and tris (2-ethylhexyl) phosphate (TEHP), while other compounds except for tris(2-chloroethyl) phosphate (TCEP) displayed biomagnification trends based on Monte Carlo simulations. Using a fugacity-based approach to normalize the accumulation of OPFRs in biota to their relative biological phase composition, storage lipid is the predominant biological phase for the mass distribution of 2-ethylhexyl diphenyl phosphate (EHDPHP) and TPHP. The water content and structure protein are equally important for TCEP, whereas lipid and structure protein are the two most important phases for other OPFRs. The mass distribution of these OPFRs along with TLs can explain their trophodynamics in the food web. The organophosphate diesters (as OPFR metabolites) also displayed biomagnification trends based on bootstrapped estimation. The correlation analysis and Korganism-water results jointly suggested the metabolites accumulation in high-TL organisms was related to biotransformation processes. The metabolite-backtracked trophic magnification factors for tri-n­butyl phosphate (TNBP) and TPHP were both greater than the values that accounted for only the parent compounds. This study highlights the incorporation of fugacity and biotransformation analysis to characterize the trophodynamic processes of OPFRs and other emerging pollutants in food webs.


Asunto(s)
Biotransformación , Retardadores de Llama , Cadena Alimentaria , Organofosfatos , Contaminantes Químicos del Agua , Retardadores de Llama/metabolismo , Organofosfatos/metabolismo , Animales , China , Contaminantes Químicos del Agua/metabolismo , Peces/metabolismo , Monitoreo del Ambiente
17.
Chem Sci ; 15(15): 5451-5481, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38638219

RESUMEN

In the era of the Internet of Things and wearable electronics, 3D-printed micro-batteries with miniaturization, aesthetic diversity and high aspect ratio, have emerged as a recent innovation that solves the problems of limited design diversity, poor flexibility and low mass loading of materials associated with traditional power sources restricted by the slurry-casting method. Thus, a comprehensive understanding of the rational design of 3D-printed materials, inks, methods, configurations and systems is critical to optimize the electrochemical performance of customizable 3D-printed micro-batteries. In this review, we offer a key overview and systematic discussion on 3D-printed micro-batteries, emphasizing the close relationship between printable materials and printing technology, as well as the reasonable design of inks. Initially, we compare the distinct characteristics of various printing technologies, and subsequently emphatically expound the printable components of micro-batteries and general approaches to prepare printable inks. After that, we focus on the outstanding role played by 3D printing design in the device architecture, battery configuration, performance improvement, and system integration. Finally, the future challenges and perspectives concerning high-performance 3D-printed micro-batteries are adequately highlighted and discussed. This comprehensive discussion aims at providing a blueprint for the design and construction of next-generation 3D-printed micro-batteries.

18.
Shock ; 61(5): 748-757, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38662612

RESUMEN

ABSTRACT: Cardiac fibrosis, characterized by excessive collagen accumulation in heart tissues, poses a significant clinical challenge in various heart diseases and complications. Although salvianolic acid A (Sal A) from Danshen ( Salvia miltiorrhiza ) has shown promise in the treatment of ischemic heart disease, myocardial infarction, and atherosclerosis, its effects on cardiac fibrosis remain unexplored. Our study investigated the efficacy of Sal A in reducing cardiac fibrosis and elucidated its underlying molecular mechanisms. We observed that Sal A demonstrated significant cardioprotective effects against Angiotensin II (Ang II)-induced cardiac remodeling and fibrosis, showing a dose-dependent reduction in fibrosis in mice and suppression of cardiac fibroblast proliferation and fibrotic protein expression in vitro . RNA sequencing revealed that Sal A counteracted Ang II-induced upregulation of Txnip, and subsequent experiments indicated that it acts through the inflammasome and ROS pathways. These findings establish the antifibrotic effects of Sal A, notably attenuated by Txnip overexpression, and highlight its significant role in modulating inflammation and oxidative stress pathways. This underscores the importance of further research on Sal A and similar compounds, especially regarding their effects on inflammation and oxidative stress, which are key factors in various cardiovascular diseases.


Asunto(s)
Angiotensina II , Proteínas Portadoras , Fibrosis , Lactatos , Transducción de Señal , Tiorredoxinas , Animales , Ratones , Transducción de Señal/efectos de los fármacos , Proteínas Portadoras/metabolismo , Masculino , Lactatos/farmacología , Lactatos/uso terapéutico , Ácidos Cafeicos/farmacología , Ácidos Cafeicos/uso terapéutico , Ratones Endogámicos C57BL , Miocardio/metabolismo , Miocardio/patología , Proteínas de Ciclo Celular/metabolismo
19.
Cell Biochem Biophys ; 82(2): 945-957, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38717641

RESUMEN

Ovarian cancer (OC) ranks as the fifth leading cause of cancer-related death in women. The main contributors to the poor prognosis of ovarian cancer are the high rates of recurrence and metastasis. Studies have indicated a crucial role for hepatitis B virus X Ag-Transactivated Protein 8 (XTP8), a protein containing the DEP domain, in various cellular processes, including cell growth, movement, and differentiation, across several types of cancers. However, the role of XTP8 in ovarian cancer remains unclear. We observed elevated expression of XTP8 in ovarian cancer. Silencing XTP8 inhibited cell proliferation, promoted apoptosis, and yielded contrasting results in cells overexpressing XTP8. Furthermore, XTP8 facilitated ovarian cancer invasion and migration, triggering epithelial-mesenchymal transition (EMT). Mechanistically, XTP8 silencing led to reduced phosphorylation levels of AKT, increased p-AMPK levels, and decreased p-mTOR levels, while XTP8 overexpression exerted the opposite effects. Additionally, the activation of p-AMPK rescued the promoting effect of XTP8 on EMT in ovarian cancer cell lines, indicating that XTP8 acts as an oncogene by modulating the AKT/AMPK/mTOR pathway. Through transcriptome sequencing to identify downstream targets of XTP8, we found that XTP8 influences the expression of Caldesmon (CALD1) at both transcriptional and translational levels. CALD1 can be considered a downstream target of XTP8. The collaborative action of XTP8 and CALD1 activates the AKT/AMPK/mTOR pathway, regulating EMT to promote ovarian cancer progression. Inhibiting this signaling axis might represent a potential therapeutic target for ovarian cancer.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Transición Epitelial-Mesenquimal , Neoplasias Ováricas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Femenino , Humanos , Proteínas Quinasas Activadas por AMP/metabolismo , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Progresión de la Enfermedad , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Neoplasias Ováricas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
20.
J Colloid Interface Sci ; 659: 984-992, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38219316

RESUMEN

Triazine-based conjugated polymers (TCPs) are promising organic catalysts for green H2 production, since their photocatalytic performance can be easily regulated via appropriate molecular design. However, apart from weak absorption of visible light, weak charge separation and transport abilities also considerably restrict the photocatalytic performance of TCPs. Herein, we report two novel TCP photocatalysts with donor-acceptor (D-A) and donor-π-acceptor (D-π-A) structures using dibenzo[g,p]chrysene (Dc), thiophene (T), and 2,4,6-triphenyl-1,3,5-triazine (Tz) as the donor, π-spacer, and acceptor, respectively. Compared to Dc-Tz with a D-A structure, Dc-T-Tz exhibits a broader light absorption edge and more efficient charge separation and transmission due to its D-π-A structure and strong dipole effect. These properties enable Dc-T-Tz to display a prominent H2 production rate of 45.13 mmol h-1 g-1 under ultraviolet-visible (UV-Vis) light (λ > 300 nm). Therefore, Dc-T-Tz represents state-of-the-art TCP photocatalysts to date.

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