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1.
ACS Omega ; 9(5): 5715-5727, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38343946

RESUMO

Concentrated coal slime serves as a clean and promising fluid fuel and is commonly employed via pipeline transportation. Currently, there are still limitations in understanding the rheological properties of coal slime, including its yield stress, viscoelasticity, and the impact of factors, such as temperature, on these properties. Therefore, we conducted tests to examine the rheological properties and yield stress of coal slime at various temperatures for two different concentrations using a pipeline transportation system and rheometers. Furthermore, due to the challenges in measuring dynamic yield stress caused by the shear bands of highly viscous slime, a method using the residual pressure inside the pipeline after cessation of transportation is proposed. The viscoelasticity of coal slime at various temperatures was examined through oscillatory shear tests. Finally, the pressure wave velocity in the pipeline transportation system was used to determine the bulk modulus. The results indicated that the shear stress under high shear rates decreased with an increase in temperature, while the yield stress and shear stress under low shear conditions gradually increased with temperature. The coal slime exhibited certain viscoelasticity with shear elasticity increasing as the temperature rose. The pressure wave velocity in the pipeline remained constant and did not vary significantly with temperature.

2.
Front Cell Dev Biol ; 11: 1179077, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601106

RESUMO

Currently, liver transplantation has reached a level of maturity where it is considered an effective treatment for end-stage liver disease and can significantly prolong the survival time of patients. However, acute and chronic rejection remain major obstacles to its efficacy. Although long-term use of immunosuppressants can prevent rejection, it is associated with serious side effects and significant economic burden for patients. Therefore, the investigation of induced immune tolerance holds crucial theoretical significance and socio-economic value. In fact, the establishment of immune tolerance in liver transplantation is intricately linked to the unique innate immune system of the liver. Kupffer cells, as a crucial component of this system, play a pivotal role in maintaining the delicate balance between inflammatory response and immune tolerance following liver transplantation. The important roles of different functions of Kupffer cells, such as phagocytosis, cell polarization, antigen presentation and cell membrane proteins, in the establishment of immune tolerance after transplantation is comprehensively summarized in this paper. Providing theoretical basis for further study and clinical application of Kupffer cells in liver transplantation.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37648554

RESUMO

BACKGROUND: Ischemia-reperfusion injury (IRI) poses a significant challenge to liver transplantation (LT). The underlying mechanism primarily involves overactivation of the immune system. Heat shock protein 110 (HSP110) functions as a molecular chaperone that helps stabilize protein structures. METHODS: An IRI model was established by performing LT on Sprague-Dawley rats, and HSP110 was silenced using siRNA. Hematoxylin-eosin staining, TUNEL, immunohistochemistry, ELISA and liver enzyme analysis were performed to assess IRI following LT. Western blotting and quantitative reverse transcription-polymerase chain reaction were conducted to investigate the pertinent molecular changes. RESULTS: Our findings revealed a significant increase in the expression of HSP110 at both the mRNA and protein levels in the rat liver following LT (P < 0.05). However, when rats were injected with siRNA-HSP110, IRI subsequent to LT was notably reduced (P < 0.05). Additionally, the levels of liver enzymes and inflammatory chemokines in rat serum were significantly reduced (P < 0.05). Silencing HSP110 with siRNA resulted in a marked decrease in M1-type polarization of Kupffer cells in the liver and downregulated the NF-κB pathway in the liver (P < 0.05). CONCLUSIONS: HSP110 in the liver promotes IRI after LT in rats by activating the NF-κB pathway and inducing M1-type polarization of Kupffer cells. Targeting HSP110 to prevent IRI after LT may represent a promising new approach for the treatment of LT-associated IRI.

4.
Am J Transplant ; 23(3): 336-352, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36695693

RESUMO

Acute rejection (AR) is an important factor that leads to poor prognosis after liver transplantation (LT). Macrophage M1-polarization is an important mechanism in AR development. MicroRNAs play vital roles in disease regulation; however, their effects on macrophages and AR remain unclear. In this study, rat models of AR were established following LT, and macrophages and peripheral blood mononuclear cells were isolated from rats and humans, respectively. We found miR-449a expression to be significantly reduced in macrophages and peripheral blood mononuclear cells. Overexpression of miR-449a not only inhibited the M1-polarization of macrophages in vitro but also improved the AR of transplant in vivo. The mechanism involved inhibiting the noncanonical nuclear factor-kappaB (NF-κB) pathway. We identified procollagen-lysine1,2-oxoglutarate5-dioxygenase 1 (PLOD1) as a target gene of miR-449a, which could reverse miR-449a's inhibition of macrophage M1-polarization, amelioration of AR, and inhibition of the NF-κB pathway. Overall, miR-449a inhibited the NF-κB pathway in macrophages through PLOD1 and also inhibited the M1-polarization of macrophages, thus attenuating AR after LT. In conclusion, miR-449a and PLOD1 may be new targets for the prevention and mitigation of AR.


Assuntos
Transplante de Fígado , MicroRNAs , Animais , Humanos , Ratos , Leucócitos Mononucleares/metabolismo , Macrófagos/metabolismo , MicroRNAs/genética , NF-kappa B/metabolismo , Pró-Colágeno/metabolismo , Pró-Colágeno/farmacologia
5.
Transplant Proc ; 54(7): 1881-1886, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35918193

RESUMO

BACKGROUND: T cell immunoglobulin domain, and mucin domain-3 (Tim-3) is associated with immunosuppression, immune tolerance, and rejection after organ transplantation, but there are no reports of rejection after human liver transplantation. This study aimed to detect Tim-3 expression after liver transplantation to determine whether Tim-3 can be used as a noninvasive index to predict immune rejection. METHODS: Quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay were performed on healthy people and patients with liver transplantation to detect Tim-3 and cytokines. Hepatic biochemical test was used to detect liver function. The study conforms to the provisions of the Declaration of Helsinki and Istanbul. RESULTS: The expression of Tim-3, alanine aminotransferase, and aspartate aminotransferase increased first and then decreased, whereas the cytokines showed upward trend. There was no significant difference in the expression of Tim-3 between preoperative patients and normal people (P > .05), whereas the expression of Tim-3 was significantly higher on the third day after operation than that before operation (P < .05). The expression of Tim-3, alanine aminotransferase, and aspartate aminotransferase peaked only once in most liver transplantation patients, but there were 3 patients that were exceptions. CONCLUSIONS: Tim-3 could be used as a potential biomarker to predict rejection after liver transplantation.


Assuntos
Receptor Celular 2 do Vírus da Hepatite A , Transplante de Fígado , Humanos , Alanina Transaminase/metabolismo , Soro Antilinfocitário , Aspartato Aminotransferases/metabolismo , Citocinas/metabolismo , Domínios de Imunoglobulina , Transplante de Fígado/efeitos adversos , Mucina-3 , Linfócitos T
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