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1.
Materials (Basel) ; 17(11)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38893950

RESUMO

A low-shrinkage and viscosity-reducing polycarboxylate superplasticizer was synthesized with maleic anhydride (MAH), diethylene glycol monobutyl ether, and methoxypoly (ethylene glycol) methacrylate (MPEGnMA). The surface tension, early shrinkage, cement paste performance, and application performance of concrete made with the synthesized water-reducing admixture were tested. A series of experiments were conducted to determine the optimal range of plastic viscosity coefficients for producing high-quality, fair-faced concrete with minimal surface defects. These experiments utilized both the synthesized water-reducing admixture alone and in combination with other water-reducing agents. The results showed that the synthesized water-reducing admixture had an ideal molecular structure, as confirmed by the GPC spectrum. When added to an aqueous solution, it reduced the surface tension from 72.47 mN/m to 30.56 mN/m. The 72 h shrinkage value of concrete was reduced by 20.6% compared with that of the conventional control group, effectively reducing shrinkage and adjusting the viscosity of the concrete mixture. Additionally, the influence of the plastic viscosity coefficient on the apparent voids in fair-faced concrete was investigated. This study revealed that when the plastic viscosity coefficient was between 5 and 10 Pa·s, the apparent void grade of the fair-faced concrete was simultaneously excellent and good. This water-reducing admixture helped prevent surface cracking and voids in fair-faced concrete, making it a suitable choice for producing high-quality fair-faced concrete surfaces.

2.
Curr Med Chem ; 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37608612

RESUMO

BACKGROUND AND OBJECTIVE: Endothelial cell activation, characterized by increased levels of vascular cell adhesion molecule 1 (VCAM-1), plays a crucial role in the development of atherosclerosis (AS). Therefore, inhibition of VCAM-1-mediated inflammatory response is of great significance in the prevention and treatment of AS. The tripartite motif (TRIM) protein-TRIM65 is involved in the regulation of cancer development, antivirals and inflammation. We aimed to study the functions of TRIM65 in regulating endothelial inflammation by interacting with VCAM-1 in atherogenesis. METHODS AND RESULTS: In vitro, we report that human umbilical vein endothelial cells (HUVECs) treated with oxidized low-density lipoprotein (oxLDL) significantly upregulate the expression of TRIM65 in a time- and dose-dependent manner. Overexpression of TRIM65 reduces oxLDL-triggered VCAM-1 protein expression, decreases monocyte adhesion to HUVECs and inhibits the production of the inflammatory cytokines IL-1ß, IL-6, IL-8, and TNF-α as well as endothelial oxLDL transcytosis. In contrast, siRNA-mediated knockdown of TRIM65 promotes the expression of VCAM-1, resulting in increased adhesion of monocytes and the release of the inflammatory cytokines IL-1ß, IL-6, IL-8, and TNF-α and enhances endothelial oxLDL transcytosis. In vivo, we measured the high expression of TRIM65 in ApoE-/- mouse aortic plaques compared to C57BL/6J mouse aortic plaques. Then, we examined whether the blood levels of VCAM-1 were higher in TRIM65 knockout ApoE-/- mice than in control mice induced by a Western diet. Furthermore, Western blot results showed that the protein expression of VCAM-1 was markedly enhanced in TRIM65 knockout ApoE-/- mouse aortic tissues compared to that of the controls. Immunofluorescence staining revealed that the expression of VCAM-1 was significantly increased in atherosclerotic plaques of TRIM65-/-/ApoE-/- aortic vessels compared to ApoE-/- controls. Mechanistically, TRIM65 specifically interacts with VCAM-1 and targets it for K48-linked ubiquitination. CONCLUSION: Our studies indicate that TRIM65 attenuates the endothelial inflammatory response by targeting VCAM-1 for ubiquitination and provides a potential therapeutic target for the inhibition of endothelial inflammation in AS.

3.
Mar Policy ; 155: 105730, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37366404

RESUMO

This paper examines seafarers' experience of fatigue during and after the pandemic. A multi-phase mixed methods research design was used, including two quantitative surveys (Nduring-pandemic=501 and Nafter-pandemic=412) and 36 in-depth interviews. Applying propensity score matching the two samples to approximate the conditions of a randomized controlled experiment, the study shows that surprisingly seafarers reported higher levels of fatigue after the pandemic. Qualitative interviews with seafarers and ship managers reveal the underlying reason - the intensified ship inspection regime together with policy and regulatory updates/revisions in the immediate aftermath of the pandemic increased seafarers' workload and made seafarers more fatigued. The results of the two surveys also show that while fatigue risk factors differed between the two periods, fatigue risk can be managed and mitigated in both periods by implementing fatigue risk management policies and practices. Policy and management implications for improving seafarers' occupational health and safety are discussed at the end of the paper.

4.
Eur J Pharmacol ; 949: 175735, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37080331

RESUMO

Pathological cardiac hypertrophy is a major cause of heart failure, and there is no effective approach for its prevention or treatment. The Trim family is a recently identified family of E3 ubiquitin ligases that regulate cardiac hypertrophy. Trim65, which is a member of the Trim family, previous studies have not determined whether Trim65 affects cardiac hypertrophy. In this study, the effects of Trim65 on isoproterenol (ISO)-induced cardiac hypertrophy and the underlying mechanisms were investigated. In contrast to C57BL/6 mice, Trim65-knockout (Trim65-KO) mice developed more severe myocardial hypertrophy, fibrosis and cardiac dysfunction after being intraperitoneally injected with ISO for 2 weeks. Transmission electron microscopy (TEM) revealed that the autophagic flux was inhibited, mitochondria were swollen, and mitochondrial cristae were lost or decreased in the myocardium of Trim65-KO mice. In vitro studies demonstrated that overexpression of Trim65 inhibited ISO-induced cardiomyocyte hypertrophy by increasing mitochondrial density and membrane potential, and the Stat1 inhibitor fludarabine attenuated the effect of Trim65 knockdown on ISO-induced cardiomyocyte hypertrophy by reducing Reactive oxygen species (ROS) production and increasing the mitochondrial density and membrane potential. Our findings provide the first link between Trim65 and mitochondria, and we found for the first time that Trim65 inhibits mitochondria-dependent apoptosis and autophagy via the Jak1/Stat1 signalling pathway, ultimately attenuating ISO-induced cardiac hypertrophy; this effect of Trim65 might be mediated via the regulation of Jak1 ubiquitination. Taking these findings together, we suggest that genes that are related to mitochondria-dependent apoptosis and that are associated with Trim65 could be promising therapeutic targets for cardiac hypertrophy.


Assuntos
Cardiomegalia , Transdução de Sinais , Camundongos , Animais , Isoproterenol/toxicidade , Camundongos Endogâmicos C57BL , Cardiomegalia/induzido quimicamente , Cardiomegalia/genética , Cardiomegalia/metabolismo , Mitocôndrias/metabolismo , Autofagia , Miócitos Cardíacos , Fator de Transcrição STAT1/metabolismo
5.
Front Cardiovasc Med ; 10: 1116509, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36873396

RESUMO

Cardiovascular disease (CVD) is the number one cause of death in the world and seriously threatens human health. Pyroptosis is a new type of cell death discovered in recent years. Several studies have revealed that ROS-induced pyroptosis plays a key role in CVD. However, the signaling pathway ROS-induced pyroptosis has yet to be fully understood. This article reviews the specific mechanism of ROS-mediated pyroptosis in vascular endothelial cells, macrophages, and cardiomyocytes. Current evidence shows that ROS-mediated pyroptosis is a new target for the prevention and treatment of cardiovascular diseases such as atherosclerosis (AS), myocardial ischemia-reperfusion injury (MIRI), and heart failure (HF).

6.
Curr Med Chem ; 30(16): 1848-1859, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35786179

RESUMO

Ferroptosis is an iron-dependent cell death, characterized by the accumulation of lipid-reactive oxygen species; various regulatory mechanisms influence the course of ferroptosis. The rapid increase in cardiovascular diseases (CVDs) is an extremely urgent problem. CVDs are characterized by the progressive deterioration of the heart and blood vessels, eventually leading to circulatory system disorder. Accumulating evidence, however, has highlighted crucial roles of ferroptosis in CVDs. Hydrogen sulfide plays a significant part in anti-oxidative stress, which may participate in the general mechanism of ferroptosis and regulate it by some signaling molecules. This review has primarily summarized the effects of hydrogen sulfide on ferroptosis and cardiovascular disease, especially the antioxidative stress, and would provide a more effective direction for the clinical study of CVDs.


Assuntos
Doenças Cardiovasculares , Ferroptose , Sulfeto de Hidrogênio , Humanos , Doenças Cardiovasculares/tratamento farmacológico , Morte Celular , Coração , Espécies Reativas de Oxigênio , Peroxidação de Lipídeos
7.
Curr Med Chem ; 30(40): 4554-4568, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36476437

RESUMO

An abdominal aortic aneurysm (AAA) is a progressive dilatation of the vascular wall occurring below the aortic fissure, preferably occurring below the renal artery. The molecular mechanism of AAA has not yet been elucidated. In the past few decades, research on abdominal aortic aneurysm has been mainly focused on the vessel wall, and it is generally accepted that inflammation and middle layer fracture of the vessel wall is the core steps in the development of AAA. However, perivascular adipose tissue plays a non-negligible role in the occurrence and development of AAA. The position of PVAT plays a supporting and protective role on the vascular wall, but the particularity of the location makes it not only have the physiological function of visceral fat; but also can regulate the vascular function by secreting a large number of adipokines and cytokines. An abdominal aortic aneurysm is getting higher and higher, with a vascular rupture, low rescue success rate, and extremely high lethality rate. At present, there is no drug to control the progression or reverse abdominal aortic aneurysm. Therefore, it is critical to deeply explore the mechanism of abdominal aortic aneurysms and find new therapeutic ways to inhibit abdominal aortic aneurysm formation and disease progression. An abdominal aortic aneurysm is mainly characterized by inflammation of the vessel wall and matrix metalloprotein degradation. In this review, we mainly focus on the cytokines released by the perivascular adipose tissue, summarize the mechanisms involved in the regulation of abdominal aortic aneurysms, and provide new research directions for studying abdominal aortic aneurysms.


Assuntos
Aneurisma da Aorta Abdominal , Motivação , Humanos , Aneurisma da Aorta Abdominal/metabolismo , Tecido Adiposo/metabolismo , Inflamação/metabolismo , Citocinas/metabolismo
8.
Curr Med Chem ; 30(31): 3550-3561, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36372915

RESUMO

Lipid metabolism is a complex biochemical process that regulates normal cell activity and death. Ferroptosis is a novel mode of programmed cell death different from apoptosis, pyroptosis, and autophagy. Abnormal lipid metabolism may lead to lipid peroxidation and cell rupture death, which are regulated by lipoxygenase (LOX), long-chain acyl-coA synthases, and antioxidant enzymes. Alternatively, Fe2+ and Fe3+ are required for the activity of LOXs and ferroptosis, and Fe2+ can significantly accelerate lipid peroxidation in ferroptosis. Abnormal lipid metabolism is a certain risk factor for cardiovascular disease. In recent years, the important role of ferroptosis in developing cardiovascular disease has been increasingly reported. Reducing lipid accumulation could reduce the occurrence of ferroptosis, thus alleviating cardiovascular disease deterioration. This article reviews the relationship of lipid peroxidation to the general mechanism of ferroptosis and highlights lipid peroxidation as the common point of ferroptosis and cardiovascular disease.


Assuntos
Doenças Cardiovasculares , Ferroptose , Humanos , Peroxidação de Lipídeos , Doenças Cardiovasculares/tratamento farmacológico , Apoptose , Morte Celular
9.
DNA Cell Biol ; 41(3): 262-275, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35180350

RESUMO

Inflammation is a double-edged sword. The moderate inflammatory response is a fundamental defense mechanism produced by the body's resistance to dangerous stimuli and a repair process of the body itself. Increasing studies have confirmed that the overactivation of the inflammasome is involved in the occurrence and development of inflammatory diseases. Strictly controlling the overactivation of the inflammasome and preventing excessive inflammatory response have always been the research focus on inflammatory diseases. However, the endogenous regulatory mechanism of inflammasome is not completely clear. The tripartite motif (TRIM) protein is one of the members of E3 ligases in the process of ubiquitination. The universality and importance of the functions of TRIM members are recognized, including the regulation of inflammatory response. This article will focus on research on the relationship between TRIMs and NLRP3 Inflammasome, which may help us make some references for future related research and the discovery of treatment methods.


Assuntos
Inflamassomos/fisiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/fisiologia , Proteínas com Motivo Tripartido/fisiologia , Animais , Inflamação/etiologia , Inflamação/fisiopatologia , Modelos Biológicos , Transdução de Sinais/fisiologia
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