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1.
J Am Chem Soc ; 146(29): 20312-20322, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38980945

RESUMEN

Organic photovoltaic (OPV) devices attain high performance with nonfullerene acceptors by utilizing the synergistic dual channels of charge generation that originate from excitations in both the donor and acceptor materials. However, the specific intermediate states that facilitate both channels are subject to debate. To address this issue, we employ time-resolved terahertz spectroscopy with improved sensitivity (ΔE/E < 10-6), enabling direct probing of charge generation dynamics in a prototypical PM6:Y6 bulk heterojunction system under one-sun-equivalent excitation density. Charge generation arising from donor excitations is characterized with a rise time of ∼9 ps, while that from acceptor excitations shows a rise time of ∼18 ps. Temperature-dependent measurements further reveal notably distinct activation energies for these two charge generation pathways. Additionally, the two channels of charge generation can be substantially manipulated by altering the ratio of bulk to interfaces. These findings strongly suggest the presence of two distinct intermediate states: interfacial and intramoiety excitations. These states are crucial in mediating the transfer of electrons and holes, driving charge generation within OPV devices.

2.
Phys Rev Lett ; 132(17): 176703, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38728713

RESUMEN

We report the picosecond spin current generation from the interface between a heavy metal and a vicinal antiferromagnet insulator Cr_{2}O_{3} by laser pulses at room temperature and zero magnetic field. It is converted into a detectable terahertz emission in the heavy metal via the inverse spin Hall effect. The vicinal interfaces are apparently the source of the picosecond spin current, as evidenced by the proportional terahertz signals to the vicinal angle. We attribute the origin of the spin current to the transient magnetic moment generated by an interfacial nonlinear magnetic-dipole difference-frequency generation. We propose a model based on the in-plane inversion symmetry breaking to quantitatively explain the terahertz intensity with respect to the angles of the laser polarization and the film azimuth. Our work opens new opportunities in antiferromagnetic and ultrafast spintronics by considering symmetry breaking.

3.
Ecotoxicol Environ Saf ; 271: 115970, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38218108

RESUMEN

The ubiquitous presence of Microplastics (MPs) in various environments documented in recent years has recently raised significant concerns about their toxic effects. While macrophages serve as the first line of defense against toxic substances and pathogens, the impact and mechanisms of microplastics on these immune cells remain unclear. This study aims to explore whether MPs induce macrophage apoptosis through the promotion of reactive oxygen species (ROS) generation and alterations in metabolic profiles. The viability of RAW264.7 cells decreased as the concentration of 0.5 µm or 5 µm MPs ranged from 0.2 to 1.5 mg/mL, with a more pronounced effect observed in the 0.5 µm MPs group. Zebrafish exposed to 0.5 µm or 5 µm MPs at a concentration of 0.5 mg/mL exhibited decreased macrophage abundance and increased apoptosis, accompanied by alterations in the expression of inflammatory and apoptosis-related genes. While 0.5 µm MPs were observed to enter macrophages, 5 µm MPs only adhered to the cell membrane surface. Both particle sizes induced ROS generation and disrupted cellular metabolism in RAW264.7 cells. Notably, macrophages exhibited a more pronounced response to 0.5 µm MPs, characterized by heightened ROS generation, increased secretion of pro-inflammatory mediators, and a significant decrease in sphingolipid metabolism. These findings suggest that the adverse effects on macrophages are greater with 0.5 µm MPs compared to 5 µm MPs, possibly attributed to particle size effects. This study contributes additional evidence on the impact of MPs on human immune cells.


Asunto(s)
Microplásticos , Plásticos , Humanos , Animales , Microplásticos/toxicidad , Especies Reactivas de Oxígeno , Pez Cebra , Macrófagos , Apoptosis , Metaboloma , Poliestirenos
4.
Chem Biodivers ; 21(6): e202400327, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38446672

RESUMEN

Four new isocoumarins, alternariethers A-C (1-3) and alternariester (4) were separated from the fermentation of the fungus Alternaria malorum FL39, purified from Myoporum bontioides. Their structures were ascertained using NMR and HR-ESI-MS spectroscopy. For compound 4, the absolute configuration was solved with the help of ECD calculation and the DP4+ method. Compared with the positive control triadimefon, compound 1 showed more potent antifungal effects on Colletotrichum musae. The antifungal effects of compounds 1, 2, and 3 on Fusarium oxysporum and Fusarium graminearum, of compound 4 on F. oxysporum, were equal to those of triadimefon. Except for compound 4 which was inactive against Escherichia coli with O78 serotype, all compounds showed moderate or weak antibacterial activity against Staphylococcus aureus ATCC 6538 and E. coli with O6 or O78 serotype.


Asunto(s)
Alternaria , Antibacterianos , Escherichia coli , Fusarium , Isocumarinas , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Alternaria/química , Alternaria/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Isocumarinas/química , Isocumarinas/farmacología , Isocumarinas/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Fusarium/efectos de los fármacos , Colletotrichum/efectos de los fármacos , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Myoporum/química , Myoporum/metabolismo
5.
PLoS One ; 19(3): e0297848, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38547044

RESUMEN

Diabetic cardiomyopathy (DCM) is a major factor in the development of heart failure. Mitochondria play a crucial role in regulating insulin resistance, oxidative stress, and inflammation, which affect the progression of DCM. Regular exercise can induce altered non-coding RNA (ncRNA) expression, which subsequently affects gene expression and protein function. The mechanism of exercise-induced mitochondrial-related non-coding RNA network in the regulation of DCM remains unclear. This study seeks to construct an innovative exercise-induced mitochondrial-related ncRNA network. Bioinformatic analysis of RNA sequencing data from an exercise rat model identified 144 differentially expressed long non-coding RNA (lncRNA) with cutoff criteria of p< 0.05 and fold change ≥1.0. GSE6880 and GSE4745 were the differentially expressed mRNAs from the left ventricle of DCM rat that downloaded from the GEO database. Combined with the differentially expressed mRNA and MitoCarta 3.0 dataset, the mitochondrial located gene Pdk4 was identified as a target gene. The miRNA prediction analysis using miRanda and TargetScan confirmed that 5 miRNAs have potential to interact with the 144 lncRNA. The novel lncRNA-miRNA-Pdk4 network was constructed for the first time. According to the functional protein association network, the newly created exercise-induced ncRNA network may serve as a promising diagnostic marker and therapeutic target, providing a fresh perspective to understand the molecular mechanism of different exercise types for the prevention and treatment of diabetic cardiomyopathy.


Asunto(s)
Diabetes Mellitus , Cardiomiopatías Diabéticas , MicroARNs , ARN Largo no Codificante , Ratas , Animales , Cardiomiopatías Diabéticas/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Redes Reguladoras de Genes
6.
Sci Adv ; 10(1): eadj7067, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38181085

RESUMEN

Biologic drugs hold immense promise for medical treatments, but their oral delivery remains a daunting challenge due to the harsh digestive environment and restricted gastrointestinal absorption. Here, inspired by the porcupinefish's ability to inflate itself and deploy its spines for defense, we proposed an intestinal microneedle robot designed to absorb intestinal fluids for rapid inflation and inject drug-loaded microneedles into the insensate intestinal wall for drug delivery. Upon reaching the equilibrium volume, the microneedle robot leverages rhythmic peristaltic contraction for mucosa penetration. The robot's barbed microneedles can then detach from its body during peristaltic relaxation and retain in the mucosa for drug releasing. Extensive in vivo experiments involving 14 minipigs confirmed the effectiveness of the intestinal peristalsis for microrobot actuation and demonstrated comparable insulin delivery efficacy to subcutaneous injection. The ingestible peristalsis-actuated microneedle robots may transform the oral administration of biologic drugs that primary relies on parenteral injection currently.


Asunto(s)
Productos Biológicos , Robótica , Animales , Porcinos , Peristaltismo , Productos Biológicos/farmacología , Porcinos Enanos , Digestión
7.
Adv Sci (Weinh) ; : e2402128, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39083289

RESUMEN

Artificial morphing surfaces, inspired by the high adaptability of biological tissues, have emerged as a significant area of research in recent years. However, the practical applications of these surfaces, constructed from soft materials, are considerably limited due to their low shear stiffness. Rigid-foldable cylinders are anisotropic structures that exhibit high adaptability and shear stiffness. Thus, they have the potential to address this issue. However, changes in shape and area at both ends during folding can lead to collisions or gaps on the morphing surface. Here, a quasi-rigid-foldable (QRF) rate is first introduced to quantify the rigid-foldability of a foldable structure and validate it through experiments. More importantly, a QRF polyhedron is then proposed, which is not only notably anisotropic, similar to a rigid-foldable cylinder, but also exhibits a zero-Poisson's ratio property, making it suitable for arraying as morphing surfaces without any collisions or gaps. Such surfaces have a myriad of applications, including modulating electromagnetic waves, gripping fragile objects, and serving as soles for climbing robots.

8.
Sci Bull (Beijing) ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39060215

RESUMEN

Combining terrestrial biomass as the reductant with submarine-type hydrothermal environments for CO2 reduction represents a possible approach for novel energy production systems that sustainably circulate carbon. However, increasing the reductive power of biomass is the main limitation of this potential method. Herein, we demonstrate that Co-doped with small amounts of Pd enhances the reduction of CO2 by selectively producing an active intermediate from carbohydrates. This catalytic reaction utilized glucose as a reductant to achieve high formate production efficiency (458.6 g kg-1) with nearly 100% selectivity with 7.5 wt% Pd1Co20/γ-Al2O3 at a moderate temperature of 225 °C. The regulation of the electronic structure of the catalytic Co surface by the dopant Pd plays a key role in promoting the C-C bond cleavage of glucose and hydrogen transfer for CO2 reduction. The findings presented here indicate that biomass can serve as the hydrogen source for CO2 reduction and provide insight into the potential utilization of CO2 in sustainable industrial applications.

9.
Micromachines (Basel) ; 15(6)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38930748

RESUMEN

The detection of the amount of aflatoxin M1 (AFM1) in milk is crucial for food safety. Here, we utilize a fiber optic (FO) localized surface plasmon resonance (LSPR) biosensor by constructing gold nanoparticle (AuNP) multimers, in which the nanogaps amplified the LSPR signal by the hot spot effect, and achieved a highly sensitive detection of f AFM1. Through the optimization of parameter conditions for the fabrication of the sensor and detection system, a high performance result from the FO LSPR biosensor was obtained, and the method for AFM1 detection was established, with a wide detection range of 0.05-100 ng/mL and a low limit of detection (LOD) of 0.04 ng/mL, and it has been successfully validated with the actual sample milk. Therefore, it is a good strategy to fabricate highly sensitive FO LSPR sensors for detecting AFM1 by constructing AuNP multimers, and this approach is suitable for developing other biosensors.

10.
Am J Clin Nutr ; 119(4): 981-989, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38211689

RESUMEN

BACKGROUND: Apolipoproteins (APOs) have emerged as significant players in lipid metabolism that affects the risk of chronic disease. However, the impact of circulating APO concentrations on premature death remains undetermined. OBJECTIVES: This study aimed to investigate the associations of serum APOs with all-cause, cardiovascular disease (CVD)-related, and cancer-related mortality. METHODS: We included 340,737 participants who had serum APO measurements from the UK Biobank. Restricted cubic splines and multivariable Cox regression models were used to assess the associations between APOs and all-cause and cause-specific mortality by computing hazard ratios (HRs) and 95% confidence intervals (CIs). Based on 1-sample Mendelian randomization (MR) design, including 398,457 participants of White ancestry who had genotyping data from the UK Biobank, we performed instrumental variable analysis with 2-stage least squares regression to assess the association between genetically predicted APOs and mortality. RESULTS: After adjusting for potential confounders including high-density and low-density lipoprotein particles, we observed nonlinear inverse relationships of APOA1 with all-cause, CVD-related, and cancer-related mortality (P-nonlinear < 0.001). By contrast, positive relationships were observed for APOB and all-cause (P-nonlinear < 0.001), CVD-related (P-linear < 0.001), and cancer-related (P-linear = 0.03) mortality. MR analysis showed consistent results, except that the association between APOB and cancer mortality was null. Furthermore, both observational and MR analyses found an inverse association between APOA1 and lung cancer-related mortality (HR comparing extreme deciles: 0.46; 95% CI: 0.26, 0.80; and HR: 0.78; 95% CI: 0.63, 0.97, respectively). CONCLUSIONS: Our findings indicate that circulating APOA1 has potential beneficial effects on all-cause, CVD-related, and lung cancer-related death risk, whereas APOB may confer detrimental effects on all-cause and CVD-related death risk.


Asunto(s)
Enfermedades Cardiovasculares , Neoplasias Pulmonares , Humanos , Análisis de la Aleatorización Mendeliana , Factores de Riesgo , Apolipoproteínas/genética , Apolipoproteínas B
11.
Int J Surg ; 110(6): 3470-3479, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38498367

RESUMEN

BACKGROUND: In colorectal cancer (CRC), tumor deposits (TD) have been used to guide the N staging only in node-negative patients. It remains unknown about the prognostic value of TD in combination with positive lymph node ratio (LNR) in stage III CRC. PATIENTS AND METHODS: The authors analyzed data from 31 139 eligible patients diagnosed with stage III CRC, including 30 230 from the Surveillance, Epidemiology, and End Results (SEER) database as a training set and 909 from two Chinese hospitals as a validation set. The associations of TD and LNR with cancer-specific survival (CSS) and overall survival (OS) were evaluated using the Kaplan-Meier method and Cox regression models. RESULTS: Both TD-positive and high LNR (value ≥0.4) were associated with worse CSS in the training [multivariable hazard ratio (HR), 1.50; 95% CI: 1.43-1.58 and HR, 1.74; 95% CI: 1.62-1.86, respectively] and validation sets (HR, 1.90; 95% CI: 1.41-2.54 and HR, 2.01; 95% CI: 1.29-3.15, respectively). Compared to patients with TD-negative and low LNR (value<0.4), those with TD-positive and high LNR had a 4.09-fold risk of CRC-specific death in the training set (HR, 4.09; 95% CI: 3.54-4.72) and 4.60-fold risk in the validation set (HR, 4.60; 95% CI: 2.88-7.35). Patients with TD-positive/H-LNR CRC on the right side had the worst prognosis ( P <0.001). The combined variable of TD and LNR contributed the most to CSS prediction in the training (24.26%) and validation (32.31%) sets. A nomogram including TD and LNR showed satisfactory discriminative ability, and calibration curves indicated favorable consistency in both the training and validation sets. CONCLUSIONS: TD and LNR represent independent prognostic predictors for stage III CRC. A combination of TD and LNR could be used to identify those at high-risk of CRC deaths.


Asunto(s)
Neoplasias Colorrectales , Índice Ganglionar , Estadificación de Neoplasias , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/mortalidad , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Pronóstico , Anciano , Metástasis Linfática , Ganglios Linfáticos/patología , Estimación de Kaplan-Meier , Programa de VERF , Adulto , Estudios de Cohortes
12.
Cancer Lett ; 597: 217057, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38876387

RESUMEN

Risk prediction tools for colorectal cancer (CRC) have potential to improve the efficiency of population-based screening by facilitating risk-adapted strategies. However, such an applicable tool has yet to be established in the Chinese population. In this study, a risk score was created using data from the China Kadoorie Biobank (CKB), a nationwide cohort study of 409,854 eligible participants. Diagnostic performance of the risk score was evaluated in an independent CRC screening programme, which included 91,575 participants who accepted colonoscopy at designed hospitals in Zhejiang Province, China. Over a median follow-up of 11.1 years, 3136 CRC cases were documented in the CKB. A risk score was created based on nine questionnaire-derived variables, showing moderate discrimination for 10-year CRC risk (C-statistic = 0.68, 95 % CI: 0.67-0.69). In the CRC screening programme, the detection rates of CRC were 0.25 %, 0.82 %, and 1.93 % in low-risk (score <6), intermediate-risk (score: 6-19), and high-risk (score >19) groups, respectively. The newly developed score exhibited a C-statistic of 0.65 (95 % CI: 0.63-0.66), surpassing the widely adopted tools such as the Asia-Pacific Colorectal Screening (APCS), modified APCS, and Korean Colorectal Screening scores (all C-statistics = 0.60). In conclusion, we developed a novel risk prediction tool that is useful to identify individuals at high risk of CRC. A user-friendly online calculator was also constructed to encourage broader adoption of the tool.


Asunto(s)
Colonoscopía , Neoplasias Colorrectales , Detección Precoz del Cáncer , Humanos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , China/epidemiología , Masculino , Femenino , Detección Precoz del Cáncer/métodos , Persona de Mediana Edad , Medición de Riesgo/métodos , Anciano , Colonoscopía/métodos , Factores de Riesgo , Tamizaje Masivo/métodos , Estudios de Cohortes , Encuestas y Cuestionarios
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