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1.
Thorac Cancer ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984468

RESUMO

BACKGROUND: Lung cancer (LC) is currently the number one malignancy death rate disease in China, and its disease burden is serious. The study aimed to analyze trends of LC and its risk factor attributable disease in China from 1990 to 2019 and predict the next 41 years. METHODS: The average annual percentage change (AAPC) was used to analyze the trend of LC and its risk factor attributable incidence, deaths, and disability-adjusted life years (DALYs) rate in China from 1990 to 2019, collected in the Global Burden of Disease 2019. Cochran-Armitage trends examine trends in lung cancer disease burden by sex, age, and attributable risk factor groups in China from 1990 to 2019. In addition, based on data on death and DALYs rate due to LC and its risk factors between 1990 and 2019, an autoregressive integrated moving average (ARIMA) model was developed to predict the change in the trend of burden of disease due to LC and its risk factors over the next 41 years, and the model was evaluated using the model parameters root mean square error, mean absolute error, and mean absolute percentage error. RESULTS: From 1990 to 2019, the incidence, mortality and DALYs of LC were all increased. Among the eight risk factors associated with lung cancer, the DALYs rate and mortality rate of lung cancer risk factors for Chinese residents increased from 1990 to 2019, except for household air pollution from solid fuels and diet low in fruit, which showed a decrease; among them, the DALYs rate and mortality rate due to ambient particulate matter pollution showed the greatest increase with AAPC values of 2.880 and 3.310, respectively, while DALYs and mortality rates due to household air pollution from solid fuels showed the largest decreases, with AAPC values of -4.755 and -4.348, respectively. The results of the ARIMA model predictions show that both the mortality rate and the rate of DALYs for lung cancer are increasing yearly, and it is predicted that the rate of DALYs for lung cancer by 2060 will reach 740.095/100 000 and the mortality rate will reach 35.151/100 000. It is expected that by 2060, the top four risk factors for lung cancer in China will be, in order of DALYs rate and mortality rate, smoking, ambient particulate matter pollution, high fasting plasma glucose (HFPG), and secondhand smoke, with HFPG showing the greatest increase. CONCLUSIONS: The LC burden increased from 1990 to 2019 in China, the LC burden that could be attributed to HFPG will continue to increase in the next 40 years, and will be the third most factor by 2060. Targeted interventions are warranted to facilitate the prevention of LC and improvement of health-related quality of life patients with LC.

2.
World J Gastrointest Oncol ; 16(6): 2769-2780, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38994173

RESUMO

BACKGROUND: Wnt/FZD-mediated signaling pathways are activated in more than 90% of hepatocellular carcinoma (HCC) cell lines. As a well-known secretory glycoprotein, Wnt3 can interact with FZD receptors on the cell surface, thereby activating the Wnt/ß-catenin signaling pathway. However, the N-glycosylation modification site of Wnt3 and the effect of this modification on the biological function of the protein are still unclear. AIM: To investigate the effect of Wnt3 N-glycosylation on the biological function of HCC cells. METHODS: Site-directed mutagenesis was used to verify the Wnt3 N-glycosylation sites, actinomycin D treatment was used to detect the stability of Wnt3 after site-directed mutation, the binding of the N-glycosylation site-directed mutant Wnt3 to FZD7 was observed by laser confocal microscopy, and the effects of the N-glycosylation site-directed mutation of Wnt3 on the Wnt/ß-catenin signaling pathway and the progression of HCC cells were detected by western blot and cell function experiments. RESULTS: Wnt3 has two N-glycosylation-modified sites (Asn90 and Asn301); when a single site at amino acid 301 is mutated, the stability of Wnt3 is weakened; the binding ability of Wnt3 to FZD7 decreases when both sites are mutated simultaneously; and the level of proteins related to the Wnt/ß-catenin signaling pathway is downregulated. Cell proliferation, migration and invasion are also weakened in the case of single 301 site and double-site mutations. CONCLUSION: These results indicate that by inhibiting the N-glycosylation of Wnt3, the proliferation, migration, invasion and colony formation abilities of liver cancer cells can be weakened, which might provide new therapeutic strategies for clinical liver cancer in the future.

3.
Materials (Basel) ; 17(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38998208

RESUMO

River silt deposited by water in coastal areas is unsuitable for engineering construction. Thus, the in situ stabilization treatment of river silt as the bearing layer has been an important research area in geotechnical engineering. The strength degradation behavior and mechanism of stabilized river silt reinforced with cement and alginate fibers (AFCS) in different engineering environments are crucial for engineering applications. Therefore, freeze-thaw (F-T) cycle tests, wetting-drying (W-D) cycle tests, water immersion tests and seawater erosion tests were conducted to explore the strength attenuation of stabilized river silt reinforced with the same cement content (9% by wet weight) and different fiber contents (0%, 0.3%, 0.6% and 0.9% by weight of wet soil) and fiber lengths (3 mm, 6 mm and 9 mm). The reinforcement and damage mechanism of AFCS was analyzed by scanning electron microscopy (SEM) imaging. The results indicate that the strength of AFCS was improved from 84% to 180% at 15 F-T cycle tests, and the strength of AFCS was improved by 26% and 40% at 30 W-D cycles, which showed better stability and excellent characteristics owing to the hygroscopic characteristics of alginate fiber arousing the release of calcium and magnesium ions within the alginate. Also, the strength attenuation of AFCS was reduced with the increase in the length and content of alginate fibers. Further, the strength of specimens in the freshwater environment was higher than that in the seawater environment at the same fiber content, and the softening coefficient of AFCS in the freshwater environment was above 0.85, indicating that the AFCS had good water stability. The optimal fiber content was found to be 0.6% based on the unconfined compressive strength (UCS) reduction in specimens cured in seawater and a freshwater environment. And the strength of AFCS was improved by about 10% compared with that of cement-stabilized soil (CS) in a seawater environment. A stable spatial network structure inside the soil was formed, in which the reinforcing effect of fibers was affected by mechanical connection, friction and interfacial bonding. However, noticeable cracks developed in the immersed and F-T specimens. These microscopic characteristics contributed to decreased mechanical properties for AFCS. The results of this research provide a reference for the engineering application of AFCS.

4.
Neural Netw ; 179: 106527, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39029298

RESUMO

A novel coronavirus discovered in late 2019 (COVID-19) quickly spread into a global epidemic and, thankfully, was brought under control by 2022. Because of the virus's unknown mutations and the vaccine's waning potency, forecasting is still essential for resurgence prevention and medical resource management. Computational efficiency and long-term accuracy are two bottlenecks for national-level forecasting. This study develops a novel multivariate time series forecasting model, the densely connected highly flexible dendritic neuron model (DFDNM) to predict daily and weekly positive COVID-19 cases. DFDNM's high flexibility mechanism improves its capacity to deal with nonlinear challenges. The dense introduction of shortcut connections alleviates the vanishing and exploding gradient problems, encourages feature reuse, and improves feature extraction. To deal with the rapidly growing parameters, an improved variation of the adaptive moment estimation (AdamW) algorithm is employed as the learning algorithm for the DFDNM because of its strong optimization ability. The experimental results and statistical analysis conducted across three Japanese prefectures confirm the efficacy and feasibility of the DFDNM while outperforming various state-of-the-art machine learning models. To the best of our knowledge, the proposed DFDNM is the first to restructure the dendritic neuron model's neural architecture, demonstrating promising use in multivariate time series prediction. Because of its optimal performance, the DFDNM may serve as an important reference for national and regional government decision-makers aiming to optimize pandemic prevention and medical resource management. We also verify that DFDMN is efficiently applicable not only to COVID-19 transmission prediction, but also to more general multivariate prediction tasks. It leads us to believe that it might be applied as a promising prediction model in other fields.

5.
Small ; : e2311818, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837617

RESUMO

The exceptional and substantial electron affinity, as well as the excellent chemical and thermal stability of transition metal oxides (TMOs), infuse infinite vitality into multifunctional applications, especially in the field of electromagnetic wave (EMW) absorption. Nonetheless, the suboptimal structural mechanical properties and absence of structural regulation continue to hinder the advancement of TMOs-based aerogels. Herein, a novel 2D tantalum disulfide (2H-TaS2) reduction strategy is demonstrated to synthesize Ta2O5/reduced graphene oxide (rGO) heterointerface aerogels with unique characters. As the prerequisite, the defects, interfaces, and configurations of aerogels are regulated by varying the concentration of 2H-TaS2 to ensure the Ta2O5/rGO heterointerface aerogels with appealing EMW absorption properties such as a minimum reflection loss (RLmin) of -61.93 dB and an effective absorption bandwidth (EAB) of 8.54 GHz (7.80-16.34 GHz). This strategy provides valuable insights for designing advanced EMW absorbers. Meanwhile, the aerogel exhibits favorable thermal insulation performance with a value of 36 mW m-1 K-1, outstanding fire resistance capability, and exceptional mechanical energy dissipation performance, making it promising for applications in the aerospace industry and consumer electronics devices.

6.
J Imaging Inform Med ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861071

RESUMO

This study aims to develop a CT-based hybrid deep learning network to predict pathological subtypes of early-stage lung adenocarcinoma by integrating residual network (ResNet) with Vision Transformer (ViT). A total of 1411 pathologically confirmed ground-glass nodules (GGNs) retrospectively collected from two centers were used as internal and external validation sets for model development. 3D ResNet and ViT were applied to investigate two deep learning frameworks to classify three subtypes of lung adenocarcinoma namely invasive adenocarcinoma (IAC), minimally invasive adenocarcinoma and adenocarcinoma in situ, respectively. To further improve the model performance, four Res-TransNet based models were proposed by integrating ResNet and ViT with different ensemble learning strategies. Two classification tasks involving predicting IAC from Non-IAC (Task1) and classifying three subtypes (Task2) were designed and conducted in this study. For Task 1, the optimal Res-TransNet model yielded area under the receiver operating characteristic curve (AUC) values of 0.986 and 0.933 on internal and external validation sets, which were significantly higher than that of ResNet and ViT models (p < 0.05). For Task 2, the optimal fusion model generated the accuracy and weighted F1 score of 68.3% and 66.1% on the external validation set. The experimental results demonstrate that Res-TransNet can significantly increase the classification performance compared with the two basic models and have the potential to assist radiologists in precision diagnosis.

7.
J Agric Food Chem ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843452

RESUMO

Structural factors that determine the amylolysis of starch-lipid complexes have remained unclear. Understanding the relationship between the structure and amylolysis of starch-lipid complexes is important for the design and preparation of complexes with predictable digestibility. In this study, the multiscale structures and amylolytic properties of complexes formed under different conditions between debranched high-amylose starch (DHAMS) and lauric, myristic, palmitic, and stearic acids were investigated. Higher complexing temperatures facilitated the formation of DHAMS-fatty acid (FA) complexes, especially the more stable type II crystallites. Longer complexing times also promoted the formation of complexes and the type II crystallites, except for DHAMS-lauric acid (LA). Molecular dynamics simulations showed that the binding free energy for the formation of DHAMS-LA complexes (10 kJ/mol) was lower than those for the other three DHAMS-FA complexes (20-50 kJ/mol), accounting for the lower stability of DHAMS-LA complexes at longer complexing times. The rate and extent of enzymatic digestion of the DHAMS-FA complexes were much lower in comparison to those of gelatinized HAMS. Correlation analyses showed that the rate and extent of enzymic digestion of DHAMS-FA complexes were mainly determined by the degree of crystallite perfection of the complexes.

8.
Molecules ; 29(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893313

RESUMO

Myeloid-derived suppressor cells (MDSCs) are recognized as major immune suppressor cells in the tumor microenvironment that may inhibit immune checkpoint blockade (ICB) therapy. Here, we developed a Stattic-loaded mesoporous silica nanoparticle (PEG-MSN-Stattic) delivery system to tumor sites to reduce the number of MDSCs in tumors. This approach is able to significantly deplete intratumoral MSDCs and thereby increase the infiltration of T lymphocytes in tumors to enhance ICB therapy. Our approach may provide a drug delivery strategy for regulating the tumor microenvironment and enhancing cancer immunotherapy efficacy.


Assuntos
Imunoterapia , Células Supressoras Mieloides , Nanopartículas , Dióxido de Silício , Microambiente Tumoral , Dióxido de Silício/química , Nanopartículas/química , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/efeitos dos fármacos , Imunoterapia/métodos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Animais , Camundongos , Porosidade , Humanos , Neoplasias/terapia , Neoplasias/imunologia , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Polietilenoglicóis/química
9.
Org Lett ; 26(26): 5447-5452, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38896796

RESUMO

Interest in electrocatalytic bioconjugation reactions has surged, particularly for modifying tryptophan and tyrosine residues in proteins. We used a cost-effective graphite felt electrode and low-current methodology to achieve selective bioconjugation of tryptophan with thiophenols, yielding up to 92%. This method exclusively labeled tryptophan residues and incorporated fluorinated tryptophan for NMR analysis. Eight polypeptides, including lanreotide and leuprorelin, were effectively coupled, demonstrating the method's versatility and potential for novel diagnostic and therapeutic agents.


Assuntos
Peptídeos , Triptofano , Triptofano/química , Peptídeos/química , Técnicas Eletroquímicas , Estrutura Molecular , Somatostatina/química , Somatostatina/análogos & derivados , Peptídeos Cíclicos/química , Eletrodos
10.
Langmuir ; 40(26): 13515-13526, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38887887

RESUMO

Carbon nanotubes (CNTs) can be regarded as a potential platform for transmembrane drug delivery as many experimental works have demonstrated their capability to effectively transport bioactive molecules into living cells. Within this framework, the loading of a peptide drug onto either the interior or exterior of CNTs has gained considerable interest. This study aims to conduct a comprehensive comparison of these two loading methods. To this end, we performed molecular dynamics simulations and the umbrella sampling technique to investigate the interaction energy, conformational changes, and free energy changes of a model peptide drug containing α-helical structure interacting with the inner or outer walls of a 14.7-nm-long (20,20) CNT. Our finding reveals that, for a tube of such dimensions, it is thermodynamically more favorable for the peptide to be loaded onto the inner tube wall than the outer tube wall, primarily due to a larger free energy change for the former strategy. Conversely, unloading the drug from the tube interior poses greater challenges. Moreover, the tube's curvature plays an essential role in influencing the conformation of the adsorbed peptide. Despite the relatively weaker van der Waals interaction between the CNT exterior and the peptide, loading the peptide onto the exterior may induce significant conformational changes, particularly affecting the peptide's α-helix structure. In contrast, loading of the peptide on the CNT interior could maintain most of the α-helical content. CNTs do not typically attract specific peptide residues, with adsorbed groups primarily determined by the peptide's configurations and orientations. Finally, we offer a guideline for selecting an optimal loading strategy for CNT-based drug delivery.


Assuntos
Simulação de Dinâmica Molecular , Nanotubos de Carbono , Peptídeos , Nanotubos de Carbono/química , Peptídeos/química , Termodinâmica , Portadores de Fármacos/química
11.
Front Endocrinol (Lausanne) ; 15: 1362774, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38904035

RESUMO

Introduction: To characterize the influence of female-specific hormones on women's thyroid function, the study investigated the influence of extra progestin from oral contraceptives on inducing thyroid dysfunction. Methods: Sixty female Wistar rats were divided into six groups based on levonorgestrel or desogestrel administration as the main active agents: control, low (0.0039 mg*20-fold), medium (0.0039 mg*100-fold), high (0.0318 mg*100-fold) levonorgestrel (pure product); and low (0.0083 mg*20-fold) and high (0.0083 mg*100-fold) desogestrel (pure product). Progestin was administered by gavage every 4 days for 1 month. Statistical analysis was performed using one-way analysis of variance and the Kruskal-Wallis test. Results: Following levonorgestrel gavage, serum free T4 and thyroidstimulating hormone levels were significantly lower in the experimental group than that in the control group (p=0.013 and 0.043). After desogestrel gavage, the serum free T4 and free T3 levels were lower in the experimental group than that in the control group (p=0.019 and 0.030). Thyroid hormone antibody concentrations were lower in rats administered levonorgestrel and desogestrel than that in control rats. Moreover, exposure to progestin upregulated the expression of the thyroid-stimulating hormone receptor and sodium iodide symporter in thyroid. Discussion: Progestin stimulation enhanced the proliferation of follicular epithelial cells in rat thyroid tissues. Progestin exposure could cause thyroid dysfunction by upregulating the transcription of thyroid-stimulating hormone receptor and sodium iodide symporter in thyroid, thus inducing pathomorphological changes in rats' thyroid.


Assuntos
Desogestrel , Levanogestrel , Progestinas , Ratos Wistar , Glândula Tireoide , Animais , Feminino , Ratos , Progestinas/farmacologia , Progestinas/efeitos adversos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Levanogestrel/farmacologia , Desogestrel/administração & dosagem , Desogestrel/farmacologia , Tiroxina/sangue , Hormônios Tireóideos/sangue , Testes de Função Tireóidea
12.
Nano Lett ; 24(21): 6386-6394, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38743576

RESUMO

Adhesion ability and interfacial thermal transfer capacity at soft/hard interfaces are of critical importance to a wide variety of applications, ranging from electronic packaging and soft electronics to batteries. However, these two properties are difficult to obtain simultaneously due to their conflicting nature at soft/hard interfaces. Herein, we report a polyurethane/silicon interface with both high adhesion energy (13535 J m-2) and low thermal interfacial resistance (0.89 × 10-6 m2 K W-1) by regulating hydrogen interactions at the interface. This is achieved by introducing a soybean-oil-based epoxy cross-linker, which can destroy the hydrogen bonds in polyurethane networks and meanwhile can promote the formation of hydrogen bonds at the polyurethane/silicon interface. This study provides a comprehensive understanding of enhancing adhesion energy and reducing interfacial thermal resistance at soft/hard interfaces, which offers a promising perspective to tailor interfacial properties in various material systems.

13.
Small ; : e2402265, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38757418

RESUMO

The emerging applications of thermally conductive elastomer composites in modern electronic devices for heat dissipation require them to maintain both high toughness and resilience under thermomechanical stresses. However, such a combination of thermal conductivity and desired mechanical characteristics is extremely challenging to achieve in elastomer composites. Here this long-standing mismatch is resolved via regulating interfacial structure and dynamics response. This regulation is realized both by tuning the molecular weight of the dangling chains in the polymer networks and by silane grafting of the fillers, thereby creating a broad dynamic-gradient interfacial region comprising of entanglements. These entanglements can provide the slipping topological constraint that allows for tension equalization between and along the chains, while also tightening into rigid knots to prevent chain disentanglement upon stretching. Combined with ultrahigh loading of aluminum-fillers (90 wt%), this design provides a low Young's modulus (350.0 kPa), high fracture toughness (831.5 J m-2), excellent resilience (79%) and enhanced thermal conductivity (3.20 W m-1 k-1). This work presents a generalizable preparation strategy toward engineering soft, tough, and resilient high-filled elastomer composites, suitable for complex environments, such as automotive electronics, and wearable devices.

14.
Small ; : e2402841, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693072

RESUMO

Developing lightweight composite with reversible switching between microwave (MW) absorption and electromagnetic interference (EMI) shielding is promising yet remains highly challenging due to the completely inconsistent attenuation mechanism for electromagnetic (EM) radiation. Here, a lightweight vanadium dioxide/expanded polymer microsphere composites foam (VO2/EPM) is designed and fabricated with porous structures and 3D VO2 interconnection, which possesses reversible switching function between MW absorption and EMI shielding under thermal stimulation. The VO2/EPM exhibits MW absorption with a broad effective absorption bandwidth of 3.25 GHz at room temperature (25 °C), while provides EMI shielding of 23.1 dB at moderately high temperature (100 °C). This reversible switching performance relies on the porous structure and tunability of electrical conductivity, complex permittivity, and impedance matching, which are substantially induced by the convertible crystal structure and electronic structure of VO2. Finite element simulation is employed to qualitatively investigate the change in interaction between EM waves and VO2/EPM before and after the phase transition. Moreover, the application of VO2/EPM is demonstrated with a reversible switching function in controlling wireless transmission on/off, showcasing its excellent cycling stability. This kind of smart material with a reversible switching function shows great potential in next-generation electronic devices.

15.
Chin Herb Med ; 16(2): 239-247, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38706823

RESUMO

Constipation is common in the diseases of the digestive system in clinics. With the change in diet structure and the increase in life pressure, the prevalence rate increases year by year. In traditional Chinese medicine (TCM), the location of the disease of constipation is in the large intestine, which is related to the dysfunction of lung, spleen, liver, kidney and other viscera. Its pathogenesis is conductive dysfunction of large intestine. Based on the theory, Shouhui Tongbian Capsule (SHTB) is composed of eight traditional Chinese medicines, including Polygoni multiflori Radix (Heshouwu in Chinese), Aloe (Luhui in Chinese), Cassiae Semen (Juemingzi in Chinese), Ginseng Radix et Rhizoma (Renshen in Chinese), Lycii Fructus (Gouqizi in Chinese), Asini Corii Colla (Ejiao in Chinese), Aurantii Fructus Immaturus (Zhishi in Chinese), and Atractylodis Macrocephalae Rhizoma (Baizhu in Chinese), which could help to release excessive turbid, and nourishing yin and supplementing qi in the treatment. This study has been carried out to review the latest advances of SHTB in the treatment of constipation. The results showed that significant effect of SHTB was found in the treatment of constipation, such as functional constipation, and constipation associated with tumor chemotherapy, colitis, type 2 diabetes and chronic cardiac failure. Besides, obvious adverse reactions were not observed. SHTB could effectively treat five types of constipation, provide direction for the future exploration of SHTB in the treatment of other types of constipation.

16.
Chemistry ; 30(40): e202400537, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38703390

RESUMO

With the popularization of 5G technology and artificial intelligence, thermally conductive epoxies with self-healing ability will be widely used in flexible electronic materials. Although many compounds containing both performances have been synthesized, there is little systematic theory to explain the coordination mechanism. In this paper, alkyl chains of different lengths were introduced to epoxies to discuss the thermally conductive, the self-healing performance, and the synergistic effect. A series of electronic-grade biphenyl epoxies (4,4'-bis(oxiran-2-ylmethoxy)-1,1'-biphenyl (1), 4,4'-bis(2-(oxiran-2-yl)ethoxy)-1,1'-biphenyl (2), 4,4'-bis(3-(oxiran-2-yl)propoxy)-1,1'-biphenyl (3), and 4,4'-bis(4-(oxiran-2-yl)butoxy)-1,1'-biphenyl (4) were synthesized and characterized. Furthermore, they were cured with decanedioic acid to produce polymers. Results showed that alkyl chains can both affect the two properties, and the epoxies suitable for specific application scenarios can be prepared by adjusting the length of alkyl chains. In terms of thermal conductivity, compound 1 was a most promising material. However, compound 4 was expected to be utilized in flexible electronic devices because of its acceptable thermal conductivity, self-healing ability, transparency, and flexibility.

17.
Adv Sci (Weinh) ; 11(26): e2401944, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38704733

RESUMO

2D magnetic materials hold substantial promise in information storage and neuromorphic device applications. However, achieving a 2D material with high Curie temperature (TC), environmental stability, and multi-level magnetic states remains a challenge. This is particularly relevant for spintronic devices, which require multi-level resistance states to enhance memory density and fulfil low power consumption and multi-functionality. Here, the synthesis of 2D non-layered triangular and hexagonal magnetite (Fe3O4) nanosheets are proposed with high TC and environmental stability, and demonstrate that the ultrathin triangular nanosheets show broad antiphase boundaries (bAPBs) and sharp antiphase boundaries (sAPBs), which induce multiple spin precession modes and multi-level resistance. Conversely, the hexagonal nanosheets display slip bands with sAPBs associated with pinning effects, resulting in magnetic-field-driven spin texture reversal reminiscent of "0" and "1" switching signals. In support of the micromagnetic simulation, direct explanation is offer to the variation in multi-level resistance under a microwave field, which is ascribed to the multi-spin texture magnetization structure and the randomly distributed APBs within the material. These novel 2D magnetite nanosheets with unique spin textures and spin dynamics provide an exciting platform for constructing real multi-level storage devices catering to emerging information storage and neuromorphic computing requirements.

18.
Langmuir ; 40(15): 8108-8114, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38568421

RESUMO

Although intense efforts have been devoted to the development of thermally conductive epoxy resin composites, most previous works ignore the importance of the contact thermal resistance between epoxy resin composites and mating surfaces. Here, we report on epoxy resin/hexagonal boron nitride (h-BN) composites, which show low contact thermal resistance with the contacting surface by tuning adhesion energy. We found that adhesion energy increases with increasing the ratio of soybean-based epoxy resin/amino silicone oil and h-BN contents. The adhesion energy has a negative correlation with the contact thermal resistance; that is, enhancing the adhesion energy will lead to reduced contact thermal resistance. The contact thermal conductance increases with the h-BN contents and is low to 0.025 mm2·K/W for the epoxy resin/60 wt % h-BN composites, which is consistent with the theoretically calculated value. By investigating the wettability and chain dynamics of the epoxy resin/h-BN composites, we confirm that the low contact thermal resistance stems from the increased intermolecular interaction between the epoxy resin chains. The present study provides a practical approach for the development of epoxy resin composites with enhanced thermal conductivity and reduced contact thermal resistance, aiming for effective thermal management of electronics.

19.
J Ethnopharmacol ; 330: 118244, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38663781

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bupleuri Radix (BR) has been recognized as an essential herbal medicine for relieving liver depression for thousands of years. Contemporary research has provided compelling evidence of its pharmacological effects, including anti-inflammatory, immunomodulatory, metabolic regulation, and anticancer properties, positioning it as a promising treatment option for various liver diseases. Hepatitis, steatohepatitis, cirrhosis, and liver cancer are among the prevalent and impactful liver diseases worldwide. However, there remains a lack of comprehensive systematic reviews that explore the prescription, bio-active components, and underlying mechanisms of BR in treating liver diseases. AIM OF THE REVIEW: To summarize the BR classical Chinese medical prescription and ingredients in treating liver diseases and their mechanisms to inform reference for further development and research. MATERIALS AND METHODS: Literature in the last three decades of BR and its classical Chinese medical prescription and ingredients were collated and summarized by searching PubMed, Wiley, Springer, Google Scholar, Web of Science, CNKI, etc. RESULTS: BR and its classical prescriptions, such as Xiao Chai Hu decoction, Da Chai Hu decoction, Si Ni San, and Chai Hu Shu Gan San, have been utilized for centuries as effective therapies for liver diseases, including hepatitis, steatohepatitis, cirrhosis, and liver cancer. BR is a rich source of active ingredients, such as saikosaponins, polysaccharides, flavonoids, sterols, organic acids, and so on. These bioactive compounds exhibit a wide range of beneficial effects, including anti-inflammatory, antioxidant, immunomodulatory, and lipid metabolism regulation. However, it is important to acknowledge that BR and its constituents can also possess hepatotoxicity, which is associated with cytochrome P450 (CYP450) enzymes and oxidative stress. Therefore, caution should be exercised when using BR in therapeutic applications to ensure the safe and appropriate utilization of its potential benefits while minimizing any potential risks. CONCLUSIONS: To sum up, BR, its compounds, and its based traditional Chinese medicine are effective in liver diseases through multiple targets, multiple pathways, and multiple effects. Advances in pharmacological and toxicological investigations of BR and its bio-active components in the future will provide further contributions to the discovery of novel therapeutics for liver diseases.


Assuntos
Bupleurum , Medicamentos de Ervas Chinesas , Hepatopatias , Animais , Humanos , Bupleurum/química , Doença Crônica , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Hepatopatias/tratamento farmacológico , Hepatopatias/metabolismo , Medicina Tradicional Chinesa/métodos , Compostos Fitoquímicos/uso terapêutico , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/química
20.
Sci Total Environ ; 931: 172567, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38643871

RESUMO

Microalgal polysaccharides have received much attention due to their potential value in preventing and regulating oxidative damage. This study aims to reveal the mechanisms of regulating oxidative stress and the differences in the yield, structure, and effect of polysaccharides extracted from three microalgae: Golenkinia sp. polysaccharides (GPS), Chlorella sorokiniana polysaccharides (CPS), and Spirulina subsalsa polysaccharides (SPS). Using the same extraction method, GPS, CPS, and SPS were all heteropoly- saccharides composed of small molecular fraction: the monosaccharides mainly comprised galactose (Gal). Among the three, SPS had a higher proportion of small molecular fraction, and a higher proportion of Gal; thus it had the highest yield and antioxidant activity. GPS, CPS, and SPS all showed strong antioxidant activity in vitro, and showed strong ability to regulate oxidative stress, among which SPS was slightly higher. From the analysis of gene expression, the Nrf2-ARE signalling pathway was an important pathway for GPS, CPS, and SPS to regulate cellular oxidative stress. This study provides a theoretical foundation for further research on the utilization of microalgae polysaccharides and product development.


Assuntos
Antioxidantes , Chlorella , Microalgas , Estresse Oxidativo , Polissacarídeos , Polissacarídeos/farmacologia , Polissacarídeos/química , Estresse Oxidativo/efeitos dos fármacos , Spirulina/química
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