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1.
Nat Commun ; 15(1): 8543, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39358379

RESUMEN

The immiscibility of hydrogen-helium mixture under the temperature and pressure conditions of planetary interiors is crucial for understanding the structures of gas giant planets (e.g., Jupiter and Saturn). While the experimental probe at such extreme conditions is challenging, theoretical simulation is heavily relied in an effort to unravel the mixing behavior of hydrogen and helium. Here we develop a method via a machine learning accelerated molecular dynamics simulation to quantify the physical separation of hydrogen and helium under the conditions of planetary interiors. The immiscibility line achieved with the developed method yields substantially higher demixing temperatures at pressure above 1.5 Mbar than earlier theoretical data, but matches better to the experimental estimate. Our results suggest a possibility that H-He demixing takes place in a large fraction of the interior radii of Jupiter and Saturn, i.e., 27.5% in Jupiter and 48.3% in Saturn. This indication of an H-He immiscible layer hints at the formation of helium rain and offers a potential explanation for the decrease of helium in the atmospheres of Jupiter and Saturn.

2.
Front Surg ; 11: 1391384, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39345658

RESUMEN

The treatment of the sequelae of severe foot injuries caused by motorcycle spoke injury, especially in pediatric patients, allows for new options and surgical protocols. The tarsometatarsal joint and the first metatarsal were reconstructed by precise preoperative design using the TSF space external fixation technique in one stage to correct the foot deformity and restore the volume and length, and free grafting of the fibular head with epiphysis in the second stage. This method is the first of its kind reported. The patient's foot deformity was corrected, walking, walking up and down stairs, and running functions were achieved, and the bone quality could grow with age. The combination of TSF six-axis spatial external fixation technique and microscopic technique can maximize the patient's appearance and function and is worth promoting.

3.
Int J Nanomedicine ; 19: 9035-9053, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39253060

RESUMEN

Background: Ischemic preconditioning-induced serum exosomes (IPC-exo) protected rat heart against myocardial ischemia/reperfusion injury. However, whether IPC-exo regulate replacement fibrosis after myocardial infarction (MI) and the underlying mechanisms remain unclear. MicroRNAs (miRs) are important cargos of exosomes and play an essential role in cardioprotection. We aim to investigate whether IPC-exo regulate post-MI replacement fibrosis by transferring cardioprotective miRs and its action mechanism. Methods: Exosomes obtained from serum of adult rats in control (Con-exo) and IPC groups were identified and analyzed, subsequently intracardially injected into MI rats following ligation. Their miRs profiles were identified using high-throughput miR sequencing to identify target miRs for bioinformatics analysis. Luciferase reporter assays confirmed target genes of selected miRs. IPC-exo transfected with selected miRs antagomir or NC were intracardially administered to MI rats post-ligation. Cardiac function and degree of replacement fibrosis were detected 4 weeks post-MI. Results: IPC-exo exerted cardioprotective effects against excessive replacement fibrosis. MiR sequencing and RT-qPCR identified miR-133a-3p as most significantly different between IPC-exo and Con-exo. MiR-133a-3p directly targeted latent transforming growth factor beta binding protein 1 (LTBP1) and protein phosphatase 2, catalytic subunit, alpha isozyme (PPP2CA). KEGG analysis showed that transforming growth factor-ß (TGF-ß) was one of the most enriched signaling pathways with miR-133a-3p. Comparing to injection of IPC-exo transfected with miR-133a-3p antagomir NC, injecting IPC-exo transfected with miR-133a-3p antagomir abolished protective effects of IPC-exo on declining excessive replacement fibrosis and cardiac function enhancement, while increasing the messenger RNA and protein expression of LTBP1, PPP2CA, and TGF-ß1in MI rats. Conclusion: IPC-exo inhibit excessive replacement fibrosis and improve cardiac function post-MI by transferring miR-133a-3p, the mechanism is associated with directly targeting LTBP1 and PPP2CA, and indirectly regulating TGF-ß pathway in rats. Our finding provides potential therapeutic effect of IPC-induced exosomal miR-133a-3p for cardiac repair.


Asunto(s)
Exosomas , MicroARNs , Infarto del Miocardio , Proteína Fosfatasa 2 , Animales , MicroARNs/sangre , MicroARNs/genética , Infarto del Miocardio/sangre , Infarto del Miocardio/terapia , Infarto del Miocardio/genética , Exosomas/metabolismo , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Fibrosis , Daño por Reperfusión Miocárdica/sangre , Daño por Reperfusión Miocárdica/terapia , Miocardio/metabolismo , Precondicionamiento Isquémico/métodos , Precondicionamiento Isquémico Miocárdico/métodos
4.
Diabetes Metab J ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39301664

RESUMEN

Background: The genetic basis for hyperglycaemia in pregnancy remain unclear. This study aimed to uncover the genetic determinants of gestational diabetes mellitus (GDM) and investigate their applications. Methods: We performed a meta-analysis of genome-wide association studies (GWAS) for GDM in Chinese women (464 cases and 1,217 controls), followed by de novo replications in an independent Chinese cohort (564 cases and 572 controls) and in silico replication in European (12,332 cases and 131,109 controls) and multi-ethnic populations (5,485 cases and 347,856 controls). A polygenic risk score (PRS) was derived based on the identified variants. Results: Using the genome-wide scan and candidate gene approaches, we identified four susceptibility loci for GDM. These included three previously reported loci for GDM and type 2 diabetes mellitus (T2DM) at MTNR1B (rs7945617, odds ratio [OR], 1.64; 95% confidence interval [CI],1.38 to 1.96]), CDKAL1 (rs7754840, OR, 1.33; 95% CI, 1.13 to 1.58), and INS-IGF2-KCNQ1 (rs2237897, OR, 1.48; 95% CI, 1.23 to 1.79), as well as a novel genome-wide significant locus near TBR1-SLC4A10 (rs117781972, OR, 2.05; 95% CI, 1.61 to 2.62; Pmeta=7.6×10-9), which has not been previously reported in GWAS for T2DM or glycaemic traits. Moreover, we found that women with a high PRS (top quintile) had over threefold (95% CI, 2.30 to 4.09; Pmeta=3.1×10-14) and 71% (95% CI, 1.08 to 2.71; P=0.0220) higher risk for GDM and abnormal glucose tolerance post-pregnancy, respectively, compared to other individuals. Conclusion: Our results indicate that the genetic architecture of glucose metabolism exhibits both similarities and differences between the pregnant and non-pregnant states. Integrating genetic information can facilitate identification of pregnant women at a higher risk of developing GDM or later diabetes.

5.
Int J Biol Macromol ; 278(Pt 2): 134604, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39137853

RESUMEN

The development of self-powered sensors with interference-resistant detection is a priority area of research for the next generation of wearable electronic devices. Nevertheless, the presence of multiple stimuli in the actual environment will result in crosstalk with the sensor, thereby hindering the ability to obtain an accurate response to a singular stimulus. Here, we present a self-powered sensor composed of silk-based conductive composite fibers (CNFA@ESF), which is capable of energy storage and sensing. The fabricated CNFA@ESF exhibits excellent mechanical performance, as well as flexibility that can withstand various deformations. The CNFA@ESF provides a good areal capacitance (44.44 mF cm-2), high-rate capability, and excellent cycle stability (91 % for 5000 cycles). In addition, CNFA@ESF also shows good sensing performance for multiple signals including strain, temperature, and humidity. It was observed that the assembly of the symmetrical device with a stiff hydrogel surface layer for protection enabled the real-time, interference-free monitoring of temperature signals. Also, the CNFA@ESF can be woven into fabrics and integrated with a solar cell to form a self-powered sensor system, which has been proven to convert and store solar energy to power electronic watches, indicating its huge potential for future wearable electronics.


Asunto(s)
Capacidad Eléctrica , Seda , Temperatura , Dispositivos Electrónicos Vestibles , Seda/química , Técnicas Biosensibles/métodos
6.
Int J Biol Macromol ; 278(Pt 2): 134618, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39151851

RESUMEN

Biomass-based slow-release fertilizers (SRFs) are a sustainable solution for addressing food scarcity, improving fertilizer efficiency, and reducing pollution, whereas they still face complex preparation, high costs, and low release characteristics. This study introduces a simple and innovative approach to producing bifunctional green SRFs with controlled release and conditioning properties for saline soils and harsh environments. The method involves a one-pot preparation of microsphere-structured amine-modified lignin slow-release fertilizer (L-UX) using biomass lignin as the starting material. The L-UX demonstrates an exceptional fertilizer loading rate (66.2 %) and extended slow-release performance (288 h), effectively enhancing the fertilizer's release ability. Compared to traditional fertilizers, the bifunctional L-UX significantly improves soil water retention capacity (824.3 %), plant growth, and germination percentage in challenging soil conditions (133 %). These findings highlight the potential of L-UX as a large-scale controlled-release fertilizer in harsh environments. A life cycle assessment (LCA) was also conducted to evaluate the environmental impact of L-UX from its production to disposal. This revealed that L-UX has a minimal environmental footprint compared to conventional inorganic fertilizers. This study further supports the widespread application of L-UX as an environmentally friendly alternative.


Asunto(s)
Aminas , Fertilizantes , Lignina , Suelo , Lignina/química , Aminas/química , Suelo/química , Preparaciones de Acción Retardada , Biomasa , Agua/química
7.
Int J Biol Macromol ; 279(Pt 1): 135090, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39191342

RESUMEN

Visual pH-responsive packaging material is particularly important in food supply chain safety monitoring due to their non-destructive monitoring method and intuitive result. However, it has always been limited by the instability performance of pH-response components and carriers, which further hinders its wide food safety application. To address these challenges, we selected cellulose with remarkable biocompatibility and mechanical properties as the carrier, and high pH-responsive curcumin to develop a smart packaging material (RC/GC composite film) with real-time food safety monitoring. Compared with pure cellulose film, the RC/GC composite film exhibited excellent mechanical properties (4-fold enhancement) and thermal stability (100 °C increasing). Meanwhile, based on the first reported strategy of curcumin in-situ growth during cellulose film formation, the RC/GC composite film exhibited exceptional antioxidant activity (89.2 %), antimicrobial property (91.6 %), and significant pH-responsive sensitivity (within 15 s). This innovative approach offers a new strategy for easy-to-use and effective monitoring of food spoilage in packaging materials.

8.
Insect Biochem Mol Biol ; 173: 104175, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39134228

RESUMEN

Carboxypeptidase A has been found across various animal species, yet its activation mechanism during the insect molting process remains elusive. Our study specifically delved into the activation mechanism of carboxypeptidase A (Bm-CPA), identified in Bombyx mori's molting fluid during metamorphosis. Initially, western blotting identified two forms of Bm-CPA, 65 kDa and 54 kDa, in the epidermis of silkworms during the molting stage. Expressing the complete Bm-CPA sequence in Pichia pastoris allowed the identification, via mass spectrometry analysis, of a 75-amino-acid propeptide for the initial hydrolysis process. Subsequently, a 35 kDa form of Bm-CPA emerged in the molting fluid, confirmed as the active form through in vitro assays, demonstrating potent carboxypeptidase A activity and faint carboxypeptidase B activity. Four potential activation sites (including Lys158/Arg159 and Arg177/Arg178) were identified through mass spectrometry and amino acid mutation analysis. RNAi of Bm-CPA indicates its critical role in molting. Finally, the carboxypeptidase inhibitor (Bm-CPI) from silkworm molting fluid was expressed to explore its role in regulating Bm-CPA activity, demonstrating a direct interaction with the 35 kDa Bm-CPA. Our research implies Bm-CPA's potential involvement in the silkworm molting process, suggesting diverse regulatory roles. These findings highlight intricate protein regulation patterns during insect metamorphosis and development.


Asunto(s)
Bombyx , Proteínas de Insectos , Muda , Animales , Bombyx/genética , Bombyx/metabolismo , Bombyx/crecimiento & desarrollo , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Larva/genética , Metamorfosis Biológica , Secuencia de Aminoácidos
9.
Int J Biol Macromol ; 276(Pt 1): 133799, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39019367

RESUMEN

The performance of cellulose-based materials is highly dependent on the choice of solvent systems. Exceptionally, cellulose dissolution and derivatization by efficient solvent have been considered as a key factor for large-scale industrial applications of cellulose. However, cellulose dissolution and derivatization often requires harsh reaction conditions, high energy consumption, and complex solubilizing, resulting in environmental impacts and low practical value. Here we address these limitations by using a low-temperature oxalic acid/sulfuric acid solvent to enable cellulose dissolution and derivatization for high-performance cellulose films. The dissolution and derivatization mechanism of the mixed acid is studied, demonstrating that cellulose is firstly socked by oxalic acid, then more hydrogen bonds ionized by sulfuric acid break cellulose chain, and finally the esterification reaction between oxalic acid and cellulose is catalyzed by sulfuric acid. Solutions containing 8 %-10 % cellulose are obtained and can be stored for a long time at -18 °C without significant degradation. Moreover, the cellulose film exhibits a higher tensile strength of up to 66.1 MPa, thermal stability, and degree of polymerization compared to that fabricated by sulfuric acid. These unique advantages provide new paths to utilize renewable resources for alternative food packaging materials at an industrial scale.


Asunto(s)
Celulosa , Embalaje de Alimentos , Ácido Oxálico , Ácidos Sulfúricos , Ácidos Sulfúricos/química , Celulosa/química , Embalaje de Alimentos/métodos , Ácido Oxálico/química , Resistencia a la Tracción , Solubilidad , Solventes/química
10.
Carbohydr Polym ; 342: 122395, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39048232

RESUMEN

Discharging wastewater from industrial dyeing and printing processes poses a significant environmental threat, necessitating green and efficient adsorbents. Cellulose nanocrystals (CNCs) have emerged as a promising option for dye adsorbing. However, the industrial production and commercialization of CNCs still faced low yield, time-consuming, and uneco-friendly. In this study, we proposed a facile hydrochloric/maleic acid (HCl/C4H4O4) hydrolysis method to synthesize carboxylated CNCs using Box-Behnken design and dual response surface design, which can systematically investigate the effect of experimental factors (temperature, time and HCl/C4H4O volume ratio) on the final products. The rod-liked carboxylated CNCs gave the highest yield of 90.50 %, maximum carboxyl content of 1.29 mmol/g, and efficient dye removal ratio of 91.5 %. Furthermore, compared to CNCs obtained by commonly sulfuric acid hydrolysis way (CNCs-S) with a Tmax of 242.6 °C, the CNCs extracted at 5 h exhibited significantly improved thermal stability with Tmax reaching 351.2 °C. The enriched carboxyl content and excellent thermal stability show potential wastewater treatment applications under harsh conditions.

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