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1.
Small ; : e2403422, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39152940

RESUMO

Conventional drug delivery techniques face challenges related to targeting and adverse reactions. Recent years have witnessed significant advancements in nanoparticle-based drug carriers. Nevertheless, concerns persist regarding their safety and insufficient metabolism. Employing cells and their derivatives, such as cell membranes and extracellular vesicles (EVs), as drug carriers effectively addresses the challenges associated with nanoparticle carriers. However, an essential hurdle remains in efficiently loading drugs into these carriers. With the advancement of microfluidic technology and its advantages in precise manipulation at the micro- and nanoscales, as well as minimal sample loss, it has found extensive application in the loading of drugs using cells and their derivatives, thereby fostering the development of drug-loading techniques. This paper outlines the characteristics and benefits of utilizing cells and their derivatives as drug carriers and provides an overview of current drug-loading techniques, particularly those rooted in microfluidic technology. The significant potential for microfluidic technology in targeted disease therapy through drug delivery systems employing cells and their derivatives, is foreseen.

2.
Micromachines (Basel) ; 15(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38675305

RESUMO

As a type of ultra-high strength steel, AerMet100 steel is used in the aerospace and military industries. Due to the fact that AerMet100 steel is difficult to machine, people have been exploring the process of additive manufacturing to fabricate AerMet100 steel. In this study, AerMet100 steel was produced using an in situ rolling hybrid with wire arc additive manufacturing. Microstructure, tensile properties, and fracture toughness of as-deposited and heat-treated AerMet100 steel were evaluated in different directions. The results reveal that the manufacturing process leads to grain fragmentation and obvious microstructural refinement of the AerMet100 steel, and weakens the anisotropy of the mechanical properties. After heat treatment, the microstructure of the AerMet100 steel is mainly composed of lath martensite and reversed austenite. Alloy carbides are precipitated within the martensitic matrix, and a high density of dislocations is the primary strengthening mechanism. The existence of film-like austenite among the martensite matrix enhances the toughness of AerMet100 steel, which coordinates stress distribution and restrains crack propagation, resulting in an excellent balance between strength and toughness. The AerMet100 steel with in situ rolling is isotropy and achieves the following values: an average ultimate strength of 1747.7 ± 16.3 MPa, yield strength of 1615 ± 40.6 MPa, elongation of 8.3 ± 0.2% in deposition direction, and corresponding values in the building direction are 1821.3 ± 22.1 MPa, 1624 ± 84.5 MPa, and 7.6 ± 1.7%, and the KIC value up to 70.6 MPa/m0.5.

3.
Sci Total Environ ; 912: 168962, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38049002

RESUMO

About 200 million tons of coal fly ash (CFA) is not effectively used in China every year. To enhance the utilization of biomass waste quinoa husk (QH) and solid waste CFA and reduce the preparation cost of superabsorbent resin (SAR), a low-cost, biodegradable modified quinoa husk-g-poly (acrylic acid)/coal fly ash superabsorbent resin (MQH-g-PAA/CFA SAR) was synthesized using modified quinoa husk (MQH), acrylic acid and CFA and used to improve the drought resistance and fertilizer conservation ability of soil. The surface morphology and performance of SAR were characterized by Fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA), which provided evidence for improving the properties of SAR by grafting MQH and adding CFA. In addition, the synthesis conditions were studied and optimized, together with the contents of initiator, crosslinker, MQH, and CFA to acrylic acid as well as the neutralization degree of acrylic acid. After optimization, the optimum water absorbency of SAR in deionized water, tap water, and physiological saline was 1302, 356, and 91 g/g respectively. The swelling and water-retention mechanisms of SARs were analyzed by a dynamic model and the results were in good agreement with the experimental data. In the soil experiment, the addition of SAR improved the drought resistance ability of soil, and reduced the leaching loss of fertilizer in the soil (from 49.5 % to 36.7 %). Therefore, this material exhibits significant potential in the field of agriculture and offers a novel approach with economic benefit for the utilization of MQH and CFA.

4.
Adv Sci (Weinh) ; 8(22): e2103314, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34643068

RESUMO

Electron density modulation is of great importance in an attempt to achieve highly active electrocatalysts for the oxygen evolution reaction (OER). Here, the successful construction of CuO@CoOOH p-n heterojunction (i.e., p-type CuO and n-type CoOOH) nanoarray electrocatalyst through an in situ anodic oxidation of CuO@CoSx on copper foam is reported. The p-n heterojunction can remarkably modify the electronic properties of the space-charge region and facilitate the electron transfer. Moreover, in situ Raman study reveals the generation of SO4 2- from CoSx oxidation, and electron cloud density distribution and density functional theory calculation suggest that surface-adsorbed SO4 2- can facilitate the OER process by enhancing the adsorption of OH- . The positively charged CoOOH in the space-charge region can significantly enhance the OER activity. As a result, the CuO@CoOOH p-n heterojunction shows significantly enhanced OER performance with a low overpotential of 186 mV to afford a current density of 10 mA cm-2 . The successful preparation of a large scale (14 × 25 cm2 ) sample demonstrates the possibility of promoting the catalyst to industrial-scale production. This study offers new insights into the design and fabrication of non-noble metal-based p-n heterojunction electrocatalysts as effective catalytic materials for energy storage and conversion.

5.
J Pharm Pharmacol ; 72(2): 209-217, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31736093

RESUMO

OBJECTIVES: This study is designed to investigate the effects and mechanisms of sinomenine (Sin) in stress load-induced heart failure in mice. METHODS: We used aortic constriction (AB) to cause pressure overload as our heart failure model. Sin was received in mice as the treatment group. Cardiac function and structural changes were detected using echocardiography. Heart-lung mass ratios were measured. The serum levels of IL-10 and IL-17 proteins were detected by using ELISA, cardiac hypertrophy markers atrial natriuretic peptide (ANP), myocardial I and III collagen mRNA levels were detected by RT-PCR. Myocardial type I and III collagen protein levels were detected by Western blotting. KEY FINDINGS: Sin significantly improved stress load-induced heart failure (P < 0.05), reduced the heart-lung mass ratio, ANP, collagen-I and -III mRNA and protein levels (P < 0.05); Sin can enhance the ratio of IL-10/IL-17. CONCLUSION: Sin may be a promising drug target to improve heart failure. Its role is related to reduce serum ANP levels, inhibit the mRNA and protein level of type I and III collagen and enhance the ratio of IL-10/IL-17.


Assuntos
Cardiotônicos/farmacologia , Insuficiência Cardíaca/tratamento farmacológico , Morfinanos/farmacologia , Animais , Fator Natriurético Atrial/sangue , Colágeno Tipo I/genética , Colágeno Tipo III/genética , Modelos Animais de Doenças , Insuficiência Cardíaca/fisiopatologia , Interleucina-10/sangue , Interleucina-17/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL
6.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(5): 402-405, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31894670

RESUMO

OBJECTIVE: To study the effects of hypericum perforatum extract (HPE) on myocardial fibrosis of the experimental autoimmune myocarditis (MFEAM) in mice. METHODS: MFEAM model of immunosuppressive mouse was established by porcine cardiac myosin. The mice in the MFEAM model group were randomly divided into: MFEAM model group (n=14), HPE 100 mg/kg group (n=13), HPE 40 mg/kg group (n=13) and captopril (Cap) 50 mg/kg control group (n=13). Drug in each group was dissolved in 0.4 ml of physiological saline each time, and administered by intragastric administration twice a day for 60 days; the normal control group (n=10) and the MFEAM model group was given normal saline at the same volume and course of treatment as above described way. The ratio of heart weight and spleen weight to body weight were calculated, the general conditions of mice were observed. The contents of procollagen I N-terminal peptide(PINP), procollagen III N-terminal peptide (PIIINP) and TGF-ß1 in serum of mice were detected. The degree of myocardial fibrosis (MF) and collagen volume fraction (CVF)were measured under the microscope by Masson staining. The protein expression of TGF-ß1 was detected by Western blot. RESULTS: The serum levels of TGF-ß1, PINP and PIIINP in the model group were higher than those in the normal group significantly (P<0.05 or P<0.01). Meanwhile , the levels of MF and CVF were increased, and the protein expression of myocardial TGF-ß1 was up-regulated. However, the serum levels of PINP, PIIINP and TGF-ß1 in HPE40 mg/kg, HPE 100 mg/kg and Cap treated-groups were decreased significantly. HPE and Cap could improve or decrease the MF level and CVF of the MFEAM model mice, and down-regulated the expression of TGF-ß1 protein in different degrees. Compared with the MFEAM model group, the difference was significant (P<0.05 or P<0.01). CONCLUSION: HPE has a therapeutic effect on MF, which may be related to its reduction of collagen deposition and inhibition of TGF-ß1 signaling pathway.


Assuntos
Cardiomiopatias , Coração , Hypericum , Extratos Vegetais , Animais , Cardiomiopatias/tratamento farmacológico , Fibrose/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Hypericum/química , Camundongos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Distribuição Aleatória , Fator de Crescimento Transformador beta1/genética
7.
J Clin Ultrasound ; 46(6): 403-407, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29635687

RESUMO

BACKGROUND: The interobserver agreement in the assessment of the grade of carotid plaque neovascularization by contrast-enhanced ultrasonography is poorly established. METHOD: We examined 140 carotid plaques in 66 patients (all patients had bilateral plaques, and 8 patients had 2 plaques on one side). We performed conventional and contrast-enhanced ultrasonography to analyze the presence of carotid plaque neovascularization, which was graded by two independent observers whose interobserver agreement (κ) was evaluated according to the thickness of carotid plaque. RESULTS: For all carotid plaques, the mean κ was 0.689 (95% confidence interval 0.604-0.774). It was 0.689 (0.569-0.808), 0.637 (0.487-0.787), and 0.740 (0.585-0.896), respectively for carotid plaques with maximal thickness <2 mm, from 2 mm to 3 mm, and >3 mm. CONCLUSION: The interobserver agreement for assessing carotid plaque neovascularization by using contrast-enhanced ultrasonography is substantial and acceptable for research purposes, regardless of the maximal thickness of the plaque.


Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Meios de Contraste , Aumento da Imagem/métodos , Placa Aterosclerótica/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/diagnóstico por imagem , Neovascularização Patológica/patologia , Variações Dependentes do Observador , Placa Aterosclerótica/patologia , Índice de Gravidade de Doença
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