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1.
J Agric Food Chem ; 72(28): 15765-15777, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38970495

RESUMO

Konjac glucomannan (KGM), high-viscosity dietary fiber, is utilized in weight management. Previous investigations on the appetite-suppressing effects of KGM have centered on intestinal responses to nutrients and gastric emptying rates, with less focus on downstream hypothalamic neurons of satiety hormones. In our studies, the molecular mechanisms through which KGM and its degradation products influence energy homeostasis via the adipocyte-hypothalamic axis have been examined. It was found that high-viscosity KGM more effectively stimulates enteroendocrine cells to release glucagon-like peptide-1 (GLP-1) and reduces ghrelin production, thereby activating hypothalamic neurons and moderating short-term satiety. Conversely, low-viscosity DKGM has been shown to exhibit stronger anti-inflammatory properties in the hypothalamus, enhancing hormone sensitivity and lowering the satiety threshold. Notably, both KGM and DKGM significantly reduced leptin signaling and fatty acid signaling in adipose tissue and activated brown adipose tissue thermogenesis to suppress pro-opiomelanocortin (POMC) expression and activate agouti-related protein (AgRP) expression, thereby reducing food intake and increasing energy expenditure. Additionally, high-viscosity KGM has been found to activate the adipocyte-hypothalamus axis more effectively than DKGM, thereby promoting greater daily energy expenditure. These findings provide novel insights into the adipocyte-hypothalamic axis for KGM to suppress appetite and reduce weight.


Assuntos
Adipócitos , Regulação do Apetite , Dieta Hiperlipídica , Metabolismo Energético , Hipotálamo , Camundongos Endogâmicos C57BL , Animais , Camundongos , Metabolismo Energético/efeitos dos fármacos , Hipotálamo/metabolismo , Hipotálamo/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Masculino , Regulação do Apetite/efeitos dos fármacos , Adipócitos/metabolismo , Adipócitos/efeitos dos fármacos , Humanos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Grelina/metabolismo , Leptina/metabolismo , Proteína Relacionada com Agouti/metabolismo , Proteína Relacionada com Agouti/genética , Termogênese/efeitos dos fármacos , Pró-Opiomelanocortina/metabolismo , Pró-Opiomelanocortina/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Obesidade/dietoterapia , Mananas
2.
Inorg Chem ; 63(14): 6305-6314, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38549559

RESUMO

MXenes are a revolutionary class of two-dimensional materials that have been recently demonstrated to exhibit promising capability of electrocatalytic CO2 reduction reaction (CO2RR) in theory and experiment. In electrocatalytic reactions, the active phases, the mechanism, and the performance can be greatly influenced by electrochemical conditions such as applied electrode potential, pH, and electrolyte. Therefore, in this first-principles study, the stable surface structures of three typical MXenes (V2C, Mo2C, and Ti3C2) with variation of electrocatalytic conditions were determined by the Pourbaix phase diagrams. Additionally, the reaction mechanism for CO2RR toward C1 products was investigated based on the thermal dynamically stable phases. The computation revealed that surfaces of all three MXenes are dominated by H* termination throughout the practical CO2RR electrochemical condition ranges. Meanwhile, the bicarbonate ions, which serve as the major electrolyte in CO2RR, show thermal dynamic unfavorability to adsorb on the surfaces. Among the three types of MXenes, V2CH exhibits higher activity in generating CO and HCOOH through the CO2RR, while Mo2CH exhibits higher activity in producing HCHO, CH3OH, and CH4. This comprehensive study provides crucial insights into the mechanism of electrocatalytic CO2RR on MXenes under realistic electrochemical conditions.

3.
J Phys Chem Lett ; 14(42): 9385-9391, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37823819

RESUMO

The poisoning of catalysts has always been a vital issue in catalytic reactions. In this study, direct observation of the interaction of CO and oxygen-poisoned Co(0001) has been achieved with scanning tunneling microscopy (STM), temperature-programmed desorption (TPD), and density functional theory calculation. A two-stage adsorption process of CO on a well-prepared p(2×2)-O layer covered Co(0001) was directly visualized. With increasing annealing time at a certain temperature after the CO dosage, the ordered (2 × 2) pattern formed in the first stage can be recovered, suggesting the weak interaction of CO with the O-covered Co(0001) surface in the latter stage. Compared to the clean Co(0001) surface, on an oxygen-poisoned surface, no further reaction was observed, illustrating the poisoning of the catalyst. Moreover, TPD results are in good agreement with the STM observation; a desorption energy of 0.35 eV is evaluated with a simple but accurate scheme.

4.
ACS Omega ; 8(20): 18186-18201, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37251129

RESUMO

High-pressure air injection (HPAI) is one of the effective methods to improve shale oil recovery after the primary depletion process. However, the seepage mechanisms and microscopic production characteristics between air and crude oil are complicated in porous media during the air flooding process. In this paper, an online nuclear magnetic resonance (NMR) dynamic physical simulation method for enhanced oil recovery (EOR) by air injection in shale oil was established by combining high-temperature and high-pressure physical simulation systems with NMR. The microscopic production characteristics of air flooding were investigated by quantifying fluid saturation, recovery, and residual oil distribution in different sizes of pores, and the air displacement mechanism of shale oil was discussed. On this basis, the effects of air oxygen concentration, permeability, injection pressure, and fracture on recovery were studied, and the migration mode of crude oil in fractures was explored. The results show that the shale oil is mainly found in <0.1 µm (small pores), followed by 0.1-1 µm (medium pores), and 1-10 µm (macropores); thus, it is critical to enhancing oil recovery in pores less than 0.1 and 0.1-1 µm. The low-temperature oxidation (LTO) reaction can occur by injecting air into depleted shale reservoirs, which has a certain effect on oil expansion, viscosity reduction, and thermal mixing phases, thereby greatly improving shale oil recovery. There is a positive relationship between air oxygen concentration and oil recovery; the recoveries of small pores and macropores can increase by 3.53 and 4.28%, respectively, and they contribute 45.87-53.68% of the produced oil. High permeability means good pore-throat connectivity and greater oil recovery, and the production degree of crude oil in three types of pores can be increased by 10.36-24.69%. Appropriate injection pressure is beneficial to increasing the oil-gas contact time and delaying gas breakthrough, but high injection pressure will result in early gas channeling, which causes the crude oil in small pores to be difficult to produce. Notably, the matrix can supply oil to fractures due to the mass exchange between matrix fractures and the increase of the oil drainage area, and the recoveries of medium pores and macropores in fractured cores increased by 9.01 and 18.39%, respectively; fractures can act as bridges for matrix crude oil migration, which means that proper fracturing before gas injection can make the EOR better. This study provides a new idea and a theoretical basis for improving shale oil recovery and clarifies the microscopic production characteristics of shale reservoirs.

5.
Cancer Med ; 10(10): 3403-3412, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33934535

RESUMO

A primary factor in tumor morbidity and mortality, lung adenocarcinoma (LUAD) is known to be a major subtype of lung cancer, having the lowest survival rate among all other cancers. Using The Cancer Genome Atlas (TCGA) database the relationship between the immune infiltrate and the NUP62CL was explored and the value of the NUP62CL expression in the prognosis and diagnosis LUAD was examined. Using the logistic regression and the Wilcoxon signed-rank test the relationship between the NUP62CL and the clinico-pathological features was analyzed. There was a significant correlation between the clinical stage (p = 0.005), the N (p = 0.004), and the decreased expression of NUP62CL. The prognosis of LUAD with high NUP62CL expression was revealed to be worse than that with low NUP62CL expression (p < 0.001) by the Kaplan-Meier survival analysis. The potentiality of NUP62CL to be a significant factor of prognosis for LUAD was indicated by the analyses of the multivariate and the univariate Cox regression models. In LUAD, the crucial role of recombination and maintenance of telomere as a significant pathway for NUP62CL was suggested by the Gene Set Enrichment Analysis (GSEA). To analyze the correlation between the genes and the tumor infiltrating immune cells the CIBERSORT was used. Moreover the positive correlation with the NUP62CL expression in LUAD of the infiltration level of the tumor infiltrating B lymphocytes and memory CD4+ T cells was exhibited by CIBERSORT. Therefore, NUP62CL may be a new valuable prognostic indicator for LUAD.


Assuntos
Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Linfócitos do Interstício Tumoral/patologia , Glicoproteínas de Membrana/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Adenocarcinoma de Pulmão/patologia , Linfócitos B/patologia , Biomarcadores Tumorais/genética , Linfócitos T CD4-Positivos/patologia , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia , Prognóstico , Modelos de Riscos Proporcionais
6.
J Obstet Gynaecol Res ; 46(1): 49-57, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31749272

RESUMO

AIM: This study aimed to explore the miR-342-3p expression in pre-eclampsia (PE) placentas and confirm whether miR-342-3p exerts effects on proliferation and migration of HTR-8/SVneo trophoblastic cells. METHODS: The PE placentas (n = 8) were taken from gravidas complicated by PE and delivered after 34 weeks. The chorionic plates and the basal plates were separately taken from the placenta disc near the position of umbilical cord insertion. RT-qPCR was used to measure the expression of miR-342-3p in the chorionic plates and the basal plates. Cell invasion assay and MMT assay were used to assess the effects of miR-342-3p on proliferation and migration of HTR-8/SVneo trophoblastic cells. Luciferase reporter assay and Western blotting were used to analyze the target of miR-342-3p and investigate the detailed mechanisms. RESULTS: The expression of miR-342-3p was upregulated in both basal plates and chorionic plates in patients with PE compared with healthy pregnant individuals. MiR-342-3p inhibitor suppressed the cell viability and invasion, and induced apoptosis in trophoblast cells. Furthermore, inhibitor of DNA binding (ID)-4 (ID4) was a direct target of miR-342-3p, and knockdown of ID4 abrogated the regulation effect of miR-342-3p on cell viability, apoptosis and invasion. CONCLUSION: Inhibition of miR-342-3p expression may suppress the occurrence of PE by targeting ID4 in vitro.


Assuntos
Proliferação de Células/genética , Proteínas Inibidoras de Diferenciação/genética , MicroRNAs/antagonistas & inibidores , Pré-Eclâmpsia/genética , Apoptose/genética , Movimento Celular/genética , Sobrevivência Celular/genética , Feminino , Humanos , Placenta/metabolismo , Gravidez , Trofoblastos , Regulação para Cima/genética
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