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1.
Angew Chem Int Ed Engl ; 62(30): e202306553, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37227067

RESUMO

Replacing the oxygen evolution reaction (OER) with the thermodynamically favorable electrooxidation of organics is considered a promising approach for the simultaneous production of hydrogen (H2 ) and high-value chemicals. However, exploring and optimizing efficient electrocatalysts remains a challenge for large-scale production of value-added steroid carbonyl and H2 . Herein, Cr-NiO/GF and Cr-Ni3 N/GF (GF: graphite felt) electrocatalysts were designed as anode and cathode for the production of steroid carbonyls and H2 , respectively. The cooperative Cr-NiO and ACT (4-acetamido-2,2,6,6-tetramethyl-1-piperidine-N-oxyl) electrocatalyst can be extended to the electrooxidation of a series of steroid alcohols to the corresponding aldehydes. Additionally, Cr-Ni3 N displays superior electrocatalytic activity for hydrogen evolution reaction (HER), with a low overpotential of 35 mV to deliver 10 mA cm-2 . Furthermore, the system coupled with anodic electrooxidation of sterol and cathodic HER exhibited excellent performance with high space-time yield of 48.85 kg m-3 h-1 for steroid carbonyl and 1.82 L h-1 for H2 generation in a two-layer stacked flow cell. Density Functional Theory (DFT) calculations indicated that Cr doping effectively stabilizes ACTH on the NiO surface, and ACTH molecule could be captured via the ketonic oxygen interaction with Cr, resulting in excellent electrocatalytic activity. This work develops a novel approach to the rational design of efficient electrocatalysts for the simultaneous production of H2 and large-scale value-added pharmaceutical carbonyl intermediates.

2.
J Med Biochem ; 42(1): 105-112, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36819133

RESUMO

Background: We intended to investigate the role and regulatory mechanism of EPS8L3 in increase the development of pancreatic cancer (PC). Methods: In order to analyze the relationship between EPS8L3 level and clinicopathological indicators of PC patients, qRT-PCR was used to detect the expression of EPS8L3 in tumor specimens of 40 PC patients. EPS8L3 knockdown models were then constructed in PC cell lines. Furthermore, the effect of EPS8L3 on PC cell function was analyzed by CCK-8 and Transwell assay. Dual luciferase reporter gene assay and recovery assay were used to further investigate the underlying mechanism. Results: qRT-PCR results indicated that EPS8L3 was highly expressed in PC tissues compared with adjacent ones. At the same time, the incidence of distant metastasis was higher in PC patients with high EPS8L3 level. In vitro analysis such as CCK-8 and Transwell experimentations indicated that knockdown of EPS8L3 markedly inhibited the proliferative and metastatic ability. Bio-informatics together with luciferase report assay proposing that EPS8L3 can target GSK3B. Western Blot results revealed that knockdown of EPS8L3 markedly reduced the GSK3B expression in PC cells, and there was a positively associated between the two in PC cells. In addition, the recovery experimentation proved that EPS8L3 and GSK3B have a mutual regulation effect. Overexpression of GSK3B can reversal the prohibitive effect of EPS8L3 knockdown on the malignant development of PC cells, thereby jointly regulating the occurrence and development of PC. Conclusions: EPS8L3 promotes the development of PC by regulating GSK3B, suggesting that EPS8L3 can be used as a biomarker for early diagnosis and treatment of PC.

3.
Rev Esp Enferm Dig ; 113(6): 411-417, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33222482

RESUMO

BACKGROUND: endoscopic submucosal dissection (ESD) has been widely recognized by patients and doctors due to its advantages in early gastric cancer (EGC). The accurate prediction of the risk of lymph node metastasis (LNM) in EGC is important to select suitable treatments with this procedure for patients. Unfortunately, the accuracy of endoscopic ultrasound and computed tomography in the diagnosis of EGC lymph node status is extremely limited. The purpose of the present study was to establish an LNM nomogram risk model of early gastric cancer patients based on clinical data, to guide treatment for clinicians. METHODS: a retrospective examination of the records of EGC patients undergoing radical gastrectomy from August 2012 to August 2019 in the Gastrointestinal Center of Subei People's Hospital was performed. The clinicopathological data were classified into a training set and validation set according to the time. Univariate and multivariate analyses were performed to identify risk factors related to LNM. A risk model for predicting the occurrence of LNM in EGC was established and validated. RESULTS: of the 503 EGC patients, 78 (15.5 %) had lymph node metastasis. Logistic stepwise regression analysis showed that the predictive factors included sex, tumor location, tumor diameter, differentiation, ulcer and lymphatic vascular invasion. The discrimination of the LNM prediction model was satisfactory with an AUC of 0.8033 (internal validation) and 0.7353 (external validation). The correction effect of the calibration was satisfactory and the DCA decision curve analysis showed a strong clinical practicability. CONCLUSION: the nomogram risk prediction model of LNM has been established for EGC patients to assist in formulating personalized treatment plans.


Assuntos
Neoplasias Gástricas , Gastrectomia , Humanos , Excisão de Linfonodo , Linfonodos , Metástase Linfática/diagnóstico por imagem , Invasividade Neoplásica , Nomogramas , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia
4.
J Cell Physiol ; 234(10): 18951-18962, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30942905

RESUMO

It is known that irisin increases total body energy expenditure, decreases body weight, and enhances insulin sensitivity. Although previous studies have demonstrated that irisin induces vascular endothelial cell (EC) angiogenesis, the molecular mechanisms underlying irisin-induced angiogenesis under conditions reflecting atherosclerosis are not known. The aim of the present study is to investigate whether irisin could inhibit oxidized low-density lipoprotein (oxLDL) impaired angiogenesis. We investigated the effect of irisin on angiogenesis in vitro by evaluating cell viability, cell migration, and the capacity to form capillary-like tubes using human umbilical vein endothelial cells and human microvascular endothelial cells (HUVECs and HMEC-1) that were treated with oxLDL. We also evaluated the effects of irisin on angiogenesis in vivo by Matrigel plug angiogenesis assay and in a chicken embryo membrane (CAM) model. Our results demonstrated that irisin increased oxLDL-treated EC viability as well as migration and tube formation. Moreover, oxLDL inhibited angiogenic response in vivo, both in the Matrigel plug angiogenesis assay and in the CAM model, and was attenuated by irisin. Furthermore, irisin decreased apoptosis, inflammatory cytokines, and intracellular reactive oxygen species (ROS) levels in oxLDL-treated EC. In addition, we found that irisin upregulated pAkt/mTOR/Nrf2 in oxLDL-treated EC. Both mTOR/Nrf2 shRNA and LY294002 could inhibit the protective effect of irisin. Taken together these results, they suggested that irisin attenuates oxLDL-induced vascular injury by activating the Akt/mTOR/Nrf2 pathway. Our findings suggest that irisin attenuates oxLDL-induced blood vessel injury.


Assuntos
Aterosclerose/prevenção & controle , Fibronectinas/metabolismo , Lipoproteínas LDL/metabolismo , Neovascularização Fisiológica/fisiologia , Animais , Apoptose/fisiologia , Aterosclerose/patologia , Linhagem Celular , Movimento Celular/fisiologia , Sobrevivência Celular/fisiologia , Embrião de Galinha , Fibronectinas/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
5.
Cell Physiol Biochem ; 41(6): 2255-2267, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28456799

RESUMO

BACKGROUND: Allicin, a major component of garlic, is regarded as a cardioprotective agent and is associated with increased endothelial function. METHODS: The effects of allicin on lipopolysaccharide (LPS)-induced vascular oxidative stress and inflammation in cultured human umbilical vein endothelial cells (HUVECs) and the mechanisms underlying these effects were studied. The protective effects were measured using cell viability, a lactate dehydrogenase (LDH) assay and cell apoptosis as indicators, and the anti-oxidative activity was determined by measuring reactive oxygen species (ROS) generation, oxidative products and endogenous antioxidant enzyme activities. HUVEC mitochondrial function was assessed by determining mitochondrial membrane potential (MMP) collapse, cytochrome c production and mitochondrial ATP release. To investigate the potential underlying mechanisms, we also measured the expression of dynamic mitochondrial proteins using western blotting. Furthermore, we evaluated the Nrf2 antioxidant signaling pathway using an enzyme-linked immunosorbent assay (ELISA). RESULTS: Our results demonstrated that allicin enhanced HUVEC proliferation, which was suppressed by LPS exposure, and LDH release. Allicin ameliorated LPS-induced apoptosis, suppressed ROS overproduction, reduced lipid peroxidation and decreased the endogenous antioxidant enzyme activities in HUVECs. These protective effects were associated with the inhibition of mitochondrial dysfunction as indicated by decreases in the MMP collapse, cytochrome c synthesis and mitochondrial ATP release. In addition, allicin attenuated the LPS-induced inflammatory responses, including endothelial cell adhesion and TNF-α and IL-8 production. Furthermore, allicin increased the expression of LXRα in a dose-dependent manner. Allicin-induced attenuation of inflammation was inhibited by LXRα siRNA treatment. Finally, allicin activated NF-E2-related factor 2 (Nrf2), which controls the defense against oxidative stress and inflammation. CONCLUSIONS: Taken together, the present data suggest that allicin attenuated the LPS-induced vascular injury process, which may be closely related to the oxidative stress and inflammatory response in HUVECs. Allicin modulated Nrf2 activation and protected the cells against LPS-induced vascular injury. Our findings suggest that allicin attenuated the LPS-induced inflammatory response in blood vessels.


Assuntos
Inflamação , Lipopolissacarídeos/toxicidade , Mitocôndrias/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ácidos Sulfínicos/farmacologia , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Citocromos c/metabolismo , Dissulfetos , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/patologia , Interleucina-8/análise , Peroxidação de Lipídeos/efeitos dos fármacos , Receptores X do Fígado/antagonistas & inibidores , Receptores X do Fígado/genética , Receptores X do Fígado/metabolismo , Malondialdeído/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Fator 2 Relacionado a NF-E2/análise , Neutrófilos/citologia , Neutrófilos/metabolismo , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/análise
6.
Chemosphere ; 168: 25-31, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27776235

RESUMO

Epigallocatechin-3-gallate (EGCG) has been shown to possess anti-inflammatory effects. Microcystin-LR (MC-LR) is a potent toxin and our past research suggested that it also mediated human umbilical vein endothelial cell (HUVEC) injury. The aim of this study was to investigate the effects of EGCG on MC-LR-induced oxidative stress and inflammatory responses in HUVECs. HUVECs were stimulated with MC-LR in the presence or absence of EGCG. MC-LR (40 µM) significantly increased cell death and decreased cell viability, migration, and tube formation, whereas EGCG (50 µM) inhibited these effects. Furthermore, the results indicated that EGCG inhibited the production of reactive oxygen species (ROS), tumor necrosis factor alpha (TNF-α), and interleukin-6 (IL-6) in MC-LR-stimulated HUVECs. Compared with MC-LR, EGCG significantly increased superoxide dismutase (SOD) and glutathione (GSH) levels and decreased malondialdehyde (MDA) levels. Moreover, the analysis indicated that EGCG suppressed MC-LR-induced NF-κB activation. In conclusion, the effects of EGCG were associated with inhibition of the NF-κB signaling pathway, which resulted in decreased ROS and TNF-α, thereby attenuating MC-LR-mediated oxidative and inflammatory responses.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Catequina/análogos & derivados , Inflamação/tratamento farmacológico , Microcistinas/efeitos dos fármacos , Catequina/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/induzido quimicamente , Interleucina-6/metabolismo , Toxinas Marinhas , Subunidade p50 de NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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