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1.
J Ethnopharmacol ; 323: 117681, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38163557

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Mulberry (Morus alba L.) leaf is a well-known herbal medicine and has been used to treat diabetes in China for thousands of years. Our previous studies have proven mulberry leaf water extract (MLWE) could improve type 2 diabetes mellitus (T2D). However, it is still unclear whether MLWE could mitigate T2D by regulating gut microbiota dysbiosis and thereof improve intestinal permeability and metabolic dysfunction through modulation of lipopolysaccharide (LPS) and endocannabinoid system (eCBs). AIM OF STUDY: This study aims to explore the potential mechanism of MLWE on the regulation of metabolic function disorder of T2D mice from the aspects of gut microbiota, LPS and eCBs. MATERIALS AND METHODS: Gut microbiota was analyzed by high-throughput 16S rRNA gene sequencing. LPS, N-arachidonoylethanolamine (AEA) and 2-ararchidonylglycerol (2-AG) contents in blood were determined by kits or liquid phase chromatography coupled with triple quadrupole tandem mass spectrometry, respectively. The receptors, enzymes or tight junction protein related to eCBs or gut barrier were detected by RT-PCR or Western blot, respectively. RESULTS: MLWE reduced the serum levels of AEA, 2-AG and LPS, decreased the expressions of N-acylphophatidylethanolamine phospholipase D, diacylglycerol lipase-α and cyclooxygenase 2, and increased the expressions of fatty acid amide hydrolase (FAAH), N-acylethanolamine-hydrolyzing acid amidase (NAAA), alpha/beta hydrolases domain 6/12 in the liver and ileum and occludin, monoacylglycerol lipase and cannabinoid receptor 1 in the ileum of T2D mice. Furthermore, MLWE could change the abundances of the genera including Acetatifactor, Anaerovorax, Bilophila, Colidextribacter, Dubosiella, Gastranaerophilales, Lachnospiraceae_NK4A136_group, Oscillibacter and Rikenella related to LPS, AEA and/or 2-AG. Moreover, obvious improvement of MLWE treatment on serum AEA level, ileum occludin expression, and liver FAAH and NAAA expression could be observed in germ-free-mimic T2D mice. CONCLUSION: MLWE could ameliorate intestinal permeability, inflammation, and glucose and lipid metabolism imbalance of T2D by regulating gut microbiota, LPS and eCBs.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Morus , Ratones , Animales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Endocannabinoides/metabolismo , Lipopolisacáridos , Morus/química , Microbioma Gastrointestinal/genética , Disbiosis/tratamiento farmacológico , Ocludina , ARN Ribosómico 16S , Hojas de la Planta/metabolismo
2.
FEBS J ; 290(18): 4577-4590, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37245155

RESUMEN

Intrinsic drug resistance mechanisms of tumor cells often reduce intracellular drug concentration to suboptimal levels. Epithelial-to-mesenchymal transition (EMT) is a pivotal process in tumor progression and metastasis that confers an aggressive phenotype as well as resistance to chemotherapeutics. Therefore, it is imperative to develop novel strategies and identify new targets to improve the overall efficacy of cancer treatment. We developed SN38 (active metabolite of irinotecan)-assembled glycol chitosan nanoparticles (cSN38) for the treatment of pancreatic ductal adenocarcinoma (PDAC). Furthermore, cSN38 and the TGF-ß1 inhibitor LY364947 formed composite nanoparticles upon self-assembly (cSN38 + LY), which obviated the poor aqueous solubility of LY364947 and enhanced drug sensitivity. The therapeutic efficacy of cSN38 + LY nanotherapeutics was studied in vitro and in vivo using suitable models. The cSN38 nanoparticles exhibited an antitumor effect that was significantly attenuated by TGF-ß-induced EMT. The cellular uptake of SN38 was impeded during EMT, which affected the therapeutic efficacy. The combination of LY364947 and cSN38 markedly enhanced the cellular uptake of SN38, increased cytotoxic effects, and inhibited EMT in PDAC cells in vitro. Furthermore, cSN38 + LY significantly inhibited PDAC xenograft growth in vivo. The cSN38 + LY nanoparticles increased the therapeutic efficacy of cSN38 via repressing the EMT of PDAC cells. Our findings provide a rationale for designing nanoscale therapeutics to combat PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Factor de Crecimiento Transformador beta/genética , Transición Epitelial-Mesenquimal/fisiología , Línea Celular Tumoral , Movimiento Celular/fisiología , Regulación Neoplásica de la Expresión Génica , Neoplasias Pancreáticas
3.
Phytother Res ; 37(8): 3195-3210, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37013717

RESUMEN

Elevations in circling branched-chain amino acids (BCAAs) levels associated with insulin resistance and type 2 diabetes mellitus (T2DM). Morus alba L. water extracts (MLE) show hypoglycemic function, but the precise mechanism remains obscure. This study is designed to investigate the association of the antidiabetes effect of MLE with the BCAAs co-metabolism modulated by host and gut microbiota. Tissue-specific expressions of BCAA-catabolizing enzymes were detected by RT-PCR and western blot, respectively. The components of the intestinal microflora were analyzed by high-throughput 16S rRNA gene sequencing. The results showed that MLE administration improved blood glucose and insulin level, decreased inflammatory cytokines expression, and lowered serum and feces BCAAs levels. Furthermore, MLE reversed the abundance changes of the bacterial genera correlated with serum and feces BCAAs, such as Anaerovorax, Bilophila, Blautia, Colidextribacter, Dubosiella, Intestinimonas, Lachnoclostridium, Lachnospiraceae_NK4A136, Oscillibacter, and Roseburia. Functionality prediction indicated that MLE potentially inhibited bacterial BCAAs biosynthesis, and promoted the tissue-specific expression of BCAAs catabolic enzyme. More importantly, MLE had obvious impacts on BCAA catabolism in germ-free-mimic T2DM mice. Those results indicated that MLE improving T2DM-related biochemical abnormalities is associated with not only gut microbiota modification but also the tissue-specific expression of BCAAs catabolic enzyme.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Resistencia a la Insulina , Morus , Ratones , Animales , Diabetes Mellitus Tipo 2/metabolismo , Morus/química , ARN Ribosómico 16S/análisis , Aminoácidos de Cadena Ramificada/análisis , Aminoácidos de Cadena Ramificada/metabolismo , Hojas de la Planta/química
4.
Cell Death Dis ; 14(2): 115, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36781842

RESUMEN

Stomach adenocarcinoma (STAD) is one of the leading causes of cancer-related death globally. Metastasis and drug resistance are two major causes of failures in current chemotherapy. Here, we found that the expression of Ras-related protein 31 (Rab31) is upregulated in human STAD tissues and high expression of Rab31 is closely associated with poor survival time. Furthermore, we revealed that Rab31 promotes cisplatin resistance and metastasis in human STAD cells. Reduced Rab31 expression induces tumor cell apoptosis and increases cisplatin sensitivity in STAD cells; Rab31 overexpression yielded the opposite result. Rab31 silencing prevented STAD cell migration, whereas the overexpression of Rab31 increased the metastatic potential. Further work showed that Rab31 mediates cisplatin resistance and metastasis via epithelial-mesenchymal transition (EMT) pathway. In addition, we found that both Rab31 overexpression and cisplatin treatment results in increased Twist1 expression. Depletion of Twist1 enhances sensitivity to cisplatin in STAD cells, which cannot be fully reversed by Rab31 overexpression. Rab31 could activate Twist1 by activating Stat3 and inhibiting Mucin 1 (MUC-1). The present study also demonstrates that Rab31 knockdown inhibited tumor growth in mice STAD models. These findings indicate that Rab31 is a novel and promising biomarker and potential therapeutic target for diagnosis, treatment and prognosis prediction in STAD patients. Our data not only identifies a novel Rab31/Stat3/MUC-1/Twist1/EMT pathway in STAD metastasis and drug resistance, but it also provides direction for the exploration of novel strategies to predict and treat STAD in the future.


Asunto(s)
Adenocarcinoma , Neoplasias Gástricas , Animales , Ratones , Humanos , Cisplatino/farmacología , Cisplatino/uso terapéutico , Cisplatino/metabolismo , Transición Epitelial-Mesenquimal/genética , Línea Celular Tumoral , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Proteína 1 Relacionada con Twist/genética , Proteína 1 Relacionada con Twist/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismo
5.
Pharmacogenomics ; 24(3): 153-162, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36718958

RESUMEN

Aim: To evaluate the association between genetic polymorphisms and plasma concentration-to-dose ratio of valproic acid (CDRV) in Chinese epileptic patients. Methods: A total of 46 epileptic patients treated with valproic acid therapy were enrolled. 18 SNPs in nine genes related to valproic acid were directly sequenced with Sanger methods. Results: Patients carrying UGT1A6 heterozygous genotypes had significantly lower CDRV than those carrying the wild-type genotypes. In contrast, patients with the homozygote genotypes of CYP2C9 and ABAT had higher CDRV than those with the wild-type genotypes and patients with the heterozygous genotypes of CYP2C19 had higher CDRV. Conclusion: Detection of genetic polymorphism in these genes might facilitate an appropriate dose of valproic acid for epileptic patients. Further studies with larger cohorts are necessary to underpin these observations.


Asunto(s)
Anticonvulsivantes , Epilepsia , Ácido Valproico , Humanos , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapéutico , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C9/genética , Pueblos del Este de Asia , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Genotipo , Polimorfismo de Nucleótido Simple , Ácido Valproico/farmacocinética , Ácido Valproico/uso terapéutico
6.
J Sep Sci ; 46(2): e2200622, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36446730

RESUMEN

Immunoassays are currently not available in commercial kits for the quantification of valproic acid, vigabatrin, pregabalin, and gabapentin, which also cannot suffer the limitations of interferences of substances with similar structures. Chromatography is a good alternative to immunoassay. In this study, a simple and robust non-derivatization gas chromatography-mass spectrometry method for simultaneous determination of the above four drugs in human plasma was developed and validated for therapeutic drug monitoring purposes. This method employed benzoic acid as the internal standard with hydrochloric acid for plasma acidification and ACN for precipitate protein. The supernatant was directly injected into gas chromatography-mass spectrometry for analysis. Good linearity was obtained with linear correlation coefficients of the four analytes of 0.9988-0.9996. Extraction recoveries of valproic acid, vigabatrin, pregabalin, and gabapentin were respectively in the ranges of 91.3%-94.5%, 90.0%-90.9%, 90.0%-92.1%, and 88.0%-92.2% with the relative standard deviation values less than 12.6%. Intra- and inter-batch precision and accuracy, and stability assays were all acceptable. Taken together, the novel method developed in this study provided easy plasma pretreatment, good extraction yield, and high chromatographic resolution, which has been successfully validated through the quantification of valproic acid in the plasma of 46 patients with epilepsy.


Asunto(s)
Ácidos Ciclohexanocarboxílicos , Vigabatrin , Humanos , Gabapentina/análisis , Vigabatrin/análisis , Pregabalina/análisis , Ácido Valproico/análisis , Anticonvulsivantes , Cromatografía de Gases y Espectrometría de Masas/métodos , Ácido gamma-Aminobutírico , Aminas/análisis , Ácidos Ciclohexanocarboxílicos/análisis , Ácidos Ciclohexanocarboxílicos/química
7.
Aging (Albany NY) ; 14(12): 5059-5074, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35700140

RESUMEN

Sepsis-induced acute lung injury (ALI) is a severe cause of death. Increasing evidence has identified circular RNAs (circRNAs) acting as critical regulators of human diseases. However, their expression pattern and underlying mechanisms in ALI remain unclear. Herein, we screened the circRNAs of ALI patients and constructed a lung injury murine model using lipopolysaccharides (LPS) induction. Functional analyses of targeted circRNA were performed in vivo and in vitro. Then, the downstream miRNA and mRNA of specific circRNAs were identified. Compared to healthy subjects, 35 circRNAs were upregulated and 9 circRNAs were downregulated in sepsis patients. The top 10 differentially expressed circRNAs were selected for validation and has_circ_0003091 was selected. The ALI mice presented significantly elevated has_circ_0003091 (mmu_circ_0015268). The functional analysis revealed that mmu_circ_0015268 contributed to the pulmonary injury, cell apoptosis, inflammatory responses, and endothelial activation in the ALI murine model. On the other hand, silencing mmu_circ_0015268 showed protective effects in LPS-treated mice and PMVECs. Furthermore, mmu_circ_0015268 sponged miR-149 to upregulate the expression of its target Smad2. In summary, we demonstrated that has_circ_0003091 might be a novel target for the management and treatment of sepsis-induced ALI.


Asunto(s)
Lesión Pulmonar Aguda , MicroARNs , Sepsis , Lesión Pulmonar Aguda/genética , Lesión Pulmonar Aguda/metabolismo , Animales , Modelos Animales de Enfermedad , Humanos , Lipopolisacáridos/farmacología , Ratones , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Sepsis/genética , Sepsis/metabolismo , Transducción de Señal , Proteína Smad2/genética , Proteína Smad2/metabolismo
8.
J Sep Sci ; 45(13): 2161-2176, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35442556

RESUMEN

We aim to establish a simple and easy high-performance liquid chromatography system coupled with an ultraviolet detector suitable for simultaneous determination of 24 antiepileptic drugs in human plasma. Optimized chromatographic separation was performed on a ZORBAX Eclipse Plus-C18 (4.6 × 150 mm2 , 3.5 µm) column with acetonitrile and 5 mM potassium dihydrogen phosphate water solution as mobile phase. Note that, 24 antiepileptic drugs were divided into three groups and eluted with different gradient procedures, respectively. The column temperature was maintained at 35°C and the detection wavelength was set at 210 nm. Plasma was processed with ethyl acetate or acetonitrile. The calibration curves of 24 antiepileptic drugs demonstrated good linearity within the test range (r > 0.996). The intra- and inter-batch precision and accuracy were all less than 15%, while extraction recoveries were in the range of 74.57-90.89% with the relative standard deviation values less than 15%. The validated methods have been successfully applied to determination of some antiepileptic drugs in rat or patient plasma. Those results indicated that the developed methods were simple and easy, and could be suitable for the determination of 24 antiepileptic drugs in plasma just by changing the gradient elution procedures of mobile phase.


Asunto(s)
Anticonvulsivantes , Acetonitrilos , Animales , Calibración , Cromatografía Líquida de Alta Presión/métodos , Humanos , Ratas
9.
RSC Adv ; 12(16): 10051-10061, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35424933

RESUMEN

A dual-template magnetic molecularly imprinted polymer (Dt-MMIP) with a specific recognition capability for carbamazepine (CBZ) and lamotrigine (LTG) was synthesized using methacrylic acid as a functional monomer, and ethylene glycol dimethylmethacrylate as a cross-linking agent. A magnetic non-molecularly imprinted polymer without templates (MNIP) was also prepared using the same procedure. The prepared polymers were characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy and adsorption experiments. Results indicated that both Dt-MMIPs and MNIPs were microspherical nanoparticles, and the surface of the Dt-MMIP was rougher than that of the MNIP. In addition, the prepared Dt-MMIPs possessed a higher adsorption capacity and better selectivity for CBZ and LTG than the MNIPs. The maximum static adsorption capacities of Dt-MMIP for CBZ and LTG were 249.5 and 647.9 µg g-1, respectively, whereas those of MNIP were 75.8 and 379.8 µg g-1, respectively. The obtained Dt-MMIPs were applied as a magnetic solid-phase extraction sorbent for the rapid and selective extraction of CBZ and LTG in rat serum samples, and determination was performed by high-performance liquid chromatography with UV detection (HPLC-UV). The developed method of dispersive SPE based on Dt-MMIPs coupled to HPLC-UV has good rapidity and selectivity, and application prospects in serum.

10.
Phytomedicine ; 98: 153959, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35134622

RESUMEN

BACKGROUND: Obesity is a worldwide problem that resulted from the excessive fat accumulation in adipose tissue, leading to the impairment of individual health. Mulberry leaf is an important traditional Chinese medicine and has been used to alleviate obesity for a long term. However, its underlying molecular mechanisms have not been fully elucidated yet. PURPOSE: In this study, we aimed to investigate the inhibition effects of mulberry leaf water extract (MLWE) on lipid accumulation during the process of differentiation of 3T3-L1 preadipocytes and development of mature adipocytes through the combination of molecular biology assays and metabolomic analysis. METHODS: The quality consistency and main chemical ingredients of MLWE were analyzed by high performance liquid chromatography and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), respectively. Oil red O staining was used to mirror lipid accumulation. Lipogenesis-, lipolysis- and inflammation-related genes were evaluated by real-time PCR and western blot, respectively. Untargeted metabolomics were performed by LC-MS/MS. RESULTS: Prepared method and quality of MLWE were stable and reliable. A total of 34 compounds were identified and 14 of them were undoubtedly confirmed. MLWE supplementation could dose-dependently inhibit the aggregation of lipid droplets, and the expressions of sterol regulatory element-binding protein (SREBP)-1c, peroxisome proliferator-activated receptor (PPAR) γ, acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), tumor necrosis factor (TNF)-α and interleukin (IL)-6, and increase the expressions of adenosine monophosphate-activated protein kinase (AMPK), hormone-sensitive lipase (HSL) and IL-10 in the differentiation of preadipocytes. Furthermore, MLWE treatment could dose-dependently decrease the level of triglycerides and the expressions of ACC, FAS, TNF-α, and IL-6, and up-regulate the level of glycerol and the expressions of PPARα, adiponectin (ADPN), adiponectin receptor (AdipoR) 1, AdipoR2, AMPK, HSL, and IL-10 in the development of mature adipocytes. Untargeted metabolomics showed that a total of 5 and 18 differential metabolites were reversed by MLWE intervention in the differentiation of preadipocytes and the development of mature adipocytes, respectively, which involved in the biosynthesis of unsaturated fatty acids, arachidonic acid metabolism and glycerophospholipids metabolism. CONCLUSION: Taken together, this study firstly verified that MLWE could effectively alleviate lipid accumulation and inflammation by regulating ADPN/AMPK-mediated signaling pathways and relevant metabolic disturbances including biosynthesis of unsaturated fatty acids, arachidonic acid metabolism and glycerophospholipids metabolism.

11.
Phytother Res ; 36(3): 1241-1257, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35129235

RESUMEN

Gut microbiota plays a key role in the pathophysiology of type 2 diabetes mellitus (T2D). Mulberry leaf has a hypoglycemic effect, but the potential mechanism is not fully understood. This study aimed to explore the influences and potential mechanisms of mulberry leaf water extract (MLWE) intervention on mice with T2D induced through a high-fat and high-sucrose diet combined with streptozotocin by the combination of fecal metabolomics and gut microbiota analysis. Results showed that MLWE could decrease fasting blood glucose and body weight while ameliorating lipid profiles, insulin resistance, liver inflammation, and the accumulation of lipid droplets in T2D mice. MLWE could reverse the abundances of the phyla Actinobacteria and Bacteroidetes and the ratio of Firmicutes/Bacteroidetes, and increase the abundances of the phyla Cyanobacteria and Epsilonbacteraeota in the feces of T2D mice. The abundances of genera Alloprevotella, Parabacteroides, Muribaculaceae, and Romboutsia in the feces of T2D mice could be reversed, while Oscillatoriales_cyanobacterium and Gastranaerophilales could be reinforced by MLWE supplementation. The levels of nine metabolites in the feces of T2D mice were improved, among which glycine, Phe-Pro, urocanic acid, phylloquinone, and lactate were correlated with Romboutsia and Gastranaerophilales. Taken together, we conclude that MLWE can effectively alleviate T2D by mediating the host-microbial metabolic axis.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Morus , Animales , Dieta Alta en Grasa/efectos adversos , Heces , Metaboloma , Ratones , Estreptozocina , Sacarosa , Agua
12.
MycoKeys ; 83: 105-121, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34602840

RESUMEN

Lichens are the result of a symbiotic interaction between fungi (mycobionts) and algae (phycobionts). Aside from mycobionts, lichen thalli can also contain non-lichenised fungal species, such as lichenicolous and endolichenic fungi. For this study, three surveys were conducted in China's Yunnan Province and Inner Mongolia Autonomous Region between 2017 and 2020. Several samples of four lichen species were collected during these surveys: Candelariafibrosa, Flavoparmeliacaperata, Flavopuncteliaflaventior and Ramalinasinensis. Six isolates of Coniochaeta were recovered from these four lichen species. The phylogenetic and morphological analyses revealed that two of these isolates were previously identified species, Coniochaetavelutinosa and C.acaciae. Those remaining were from potentially unknown species. We used molecular and morphological data to describe these previously-unknown species as Coniochaetafibrosae sp. nov., C.mongoliae sp. nov. and C.sinensis sp. nov. The findings of this study significantly improve our understanding of the variety and habitat preferences of Coniochaeta in China and globally.

13.
Dalton Trans ; 49(17): 5677-5683, 2020 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-32292974

RESUMEN

The "shuttle effect" of long-chain polysulfides and the low conductivity of elemental sulfur lead to the inferior cycling stability of lithium-sulfur batteries and imped their practical applications. Herein, Co3O4 nanoflakes with uniform macro pores distribution were synthesized via facile oil bath and calcination methods. Coupled with super P and coated on common polypropylene separators, they were expected to hinder the migration of lithium polysulfides (LiPSs) and accelerate the redox kinetics of polysulfides. Coin cells assembled with the Co3O4-super P interlayer exhibited a capacity of 760 mA h g-1 at 1 C, maintained 598 mA h g-1 after 350 cycles, and the decay rate of discharge capacity was only about 0.062% per cycle. Such high performance can be attributed to the synergistic effects between polar Co3O4 and conductive super P. The facile fabrication method and high performance make the Co3O4-super P interlayer a feasible material to apply in lithium-sulfur batteries.

14.
Inorg Chem ; 59(7): 4483-4492, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-32174112

RESUMEN

Three classical Fe-MOFs, viz., MIL-100(Fe), MIL-101(Fe), and MIL-53(Fe), were synthesized to serve as platforms for the investigation of structure-activity relationship and catalytic mechanism in the selective conversion of H2S to sulfur. The physicochemical properties of the Fe-MOFs were characterized by various techniques. It was disclosed that the desulfurization performances of Fe-MOFs with well-defined microstructures are obviously different. Among these, MIL-100(Fe) exhibits the highest catalytic performance (ca. 100% H2S conversion and 100% S selectivity at 100-180 °C) that is superior to that of commercial Fe2O3. Furthermore, the results of systematic characterization and DFT calculation reveal that the difference in catalytic performance is mainly because of discrepancy in the amount of Lewis acid sites. A plausible catalytic mechanism has been proposed for H2S selective conversion over Fe-MOFs. This work provides critical insights that are helpful for rational design of desulfurization catalysts.

15.
Dalton Trans ; 48(34): 12832-12838, 2019 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-31418005

RESUMEN

MoO3-x nanobelts with different concentrations of oxygen vacancies were synthesized by a one-step hydrothermal process. XPS test results show that oxygen vacancies are distributed from the exterior to the interior of the MoO3-x nanobelts. As an anode material for lithium-ion batteries, MoO3-x-10 releases excellent rate capacitance. It can maintain a high specific capacitance of about 500 mA h·g-1 at a high current density of 1000 mA·g-1. In the aspect of cycling stability, MoO3-x-10 can retain a high specific capacity of 641 mA h·g-1 after cycling for 50 times at 100 mA·g-1 and 420 mA h·g-1 after cycling for 100 times at 500 mA·g-1. The coexistence of oxygen vacancies and low-valence Mo ions is conducive to the intercalation/de-intercalation of Li ions and to promoting redox reactions. It has been proved to be a significantly effective way in which oxygen vacancies can improve the integrated performance of MoO3-x nanobelts as anode materials.

16.
Artículo en Inglés | MEDLINE | ID: mdl-30690396

RESUMEN

Ginkgo biloba leaves extract (GBE), one of the most widely used traditional Chinese medicines worldwide, can be used for the treatment of diabetes mellitus (DM). However, its biotransformation in liver is not fully known under the state of DM. In this study, an off-line hydrophilic interaction × reversed-phase two-dimensional liquid chromatography (HILIC × RP 2D-LC) system coupled with diode array detection (DAD) and quadrupole time-of-flight mass spectrometry (q/TOF-MS) was established for the qualification and quantification of the biotransformation of GBE in normal and diabetic rat liver microsomes (RLMs). 6 metabolites were tentatively identified according to the exact molecular weights and the characteristic fragment ions provided by q/TOF-MS data. The results of metabolic stability showed that the metabolic ratio of four target compounds including quercetin, genistein, kaempferol and isorhamnetin in diabetic RLMs were significantly enhanced when comparing with normal RLMs. The results of enzyme kinetics showed that compared with normal RLMs, the Michaelis-Menten constant (Km) value of genistein was obvious increased while its maximal velocity (Vmax) and intrinsic clearance (CLint) values were significantly decreased by diabetic RLMs, and the Vmax and CLint values of kaempferol and isorhamnetin were notably enhanced while their Km values were markedly reduced. For the half-time (t1/2) values of four target compounds and the Km, Vmax and CLint values of quercetin, there were not statistically significant changes between normal and diabetic RLMs. The results suggest that the developed off-line 2D LC-DAD-q/TOF-MS method is an easy and accurate approach for the study of GBE biotransformation in RLMs and may provide the essential data for further pharmacological and clinical studies of GBE.


Asunto(s)
Cromatografía de Fase Inversa/métodos , Espectrometría de Masas/métodos , Microsomas Hepáticos/metabolismo , Extractos Vegetales/análisis , Extractos Vegetales/farmacocinética , Animales , Biotransformación , Ginkgo biloba , Límite de Detección , Modelos Lineales , Masculino , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados
17.
Inorg Chem ; 57(16): 10081-10089, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30080025

RESUMEN

Classical amino-functionalized Fe-terephthalate metal-organic framework NH2-MIL-53(Fe) and its parent framework MIL-53(Fe) were prepared via simple hydrothermal methods. The catalytic performaces of these two Fe-MOFs were explored for the selective oxidation of H2S. The physicochemical properties of the fresh and used Fe-MOFs catalysts were investigated by XRD, BET, SEM, FT-IR, CO2-TPD, and XPS techniques. It was found that the introduction of amino groups reduces the activation energies for H2S oxidation and endows this catalyst surface with moderate basic sites. As a result, the NH2-MIL-53(Fe) catalyst displays high H2S conversion and near 100% S selectivity in the temperature range of 130-160 °C, outperforming commercial Fe2O3 and activated carbon. Moreover, a plausible reaction route for H2S selective oxidation over NH2-MIL-53(Fe) is proposed. This work opens up the possibility of utilizing MOFs as efficient catalyst for desulfuration reactions.

18.
Chemosphere ; 207: 267-277, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29803158

RESUMEN

An important pathway for biochar to alter the availability of soil phosphorus (P) is to change P sorption characteristics of the soil. The aim of this study was to understand the mechanisms of biochar effects on P sorption in acid upland red soils in the presence of different concentrations of exogenous P. Rice straw biochar (RSB) was prepared and applied at rates of 0, 1%, 3%, and 5% (w/w) to three red soils (MZ1, MZ2, and QY1) differing in initial pH (pH = 4.31, 4.82, and 5.68, respectively). The P sorption characteristics of these red soils were described using the Langmuir and Temkin equations and their relationships with soil basic physicochemical properties were analyzed. Furthermore, a representative red soil (MZ2) was selected to analyze the zeta potential of soil colloids and the chemical properties of sorption equilibrium solution, in order to understand their relationships with P sorption characteristics. Results showed that within a certain range of P concentration in the equilibrium solution, the amount of P sorbed by the three red soils decreased and the corresponding amount of P desorbed increased with increasing amendment rate of RSB. RSB showed the greatest effect on P desorption characteristics of MZ2 soil in the presence of higher exogenous P concentration. With increasing RSB amendment rate, the maximum P sorption of MZ1 soil decreased, while those of MZ2 and QY1 soils increased after an initial decrease. Phosphate sorption equilibrium constant and maximum P buffer capacity of each soil first increased and then decreased. However, a single physicochemical property could not interpret complex changes in multi-factors that jointly determine the P sorption characteristics of red soils. In the case of MZ2 soil, RSB amendment shifted the zeta potential of soil colloids to the negative direction; this decreased the positive charge and increased the negative charge on the soil surface, thus reducing P sorption in the MZ2 soil. In the presence of the same concentration of exogenous P, RSB amendment altered the pH, dissolved organic C (DOC), humification index (HIX), and maximum fluorescence intensity (Fmax) in the sorption equilibrium solution. In most cases, the amount of P sorbed by the MZ2 soil was negatively correlated with the pH value, DOC concentration, HIX value, and Fmax value of humic-like dissolved organic matter (DOM), and positively correlated with the Fmax value of protein-like DOM (P < 0.05 or P < 0.01). The relative fractional distribution of the contents for humic-like and protein-like DOM might determine the difference in the P sorption characteristics of MZ2 soil. In conclusion, different amendment rates of RSB affected the release of phosphate from soil surfaces into the solution by altering basic physicochemical and electrochemical properties of red soils and chemical properties of sorption equilibrium solution.


Asunto(s)
Carbón Orgánico/química , Oryza/química , Fósforo/química , Contaminantes del Suelo/química , Suelo/química
19.
Oncotarget ; 7(17): 24348-60, 2016 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-27028999

RESUMEN

Eukaryotic translation initiation factor 5A2 (eIF5A2) has been identified as a critical gene in tumor metastasis. Research has suggested that reactive oxygen species (ROS) serve as signaling molecules in cancer cell proliferation and migration. However, the mechanisms linking eIF5A2 and ROS are not fully understood. Here, we investigated the effects of ROS on the eIF5A2-induced epithelial-mesenchymal transition (EMT) and migration in six hepatocellular carcinoma (HCC) cell lines. Western hybridization, siRNA transfection, transwell migration assays, wound-healing assays, and immunofluorescence analysis were used. The protein levels of eIF5A2 in tumor and adjacent tissue samples from 90 HCC patients with detailed clinical, pathological, and clinical follow-up data were evaluated. Overexpression of eIF5A2 was found in cancerous tissues compared with adjacent tissues. We found that eIF5A2 overexpression in HCC was associated with reduced overall survival. Knockdown of eIF5A2 and intracellular reduction of ROS significantly suppressed the invasion and metastasis of HCC cells. Interestingly, N1-guanyl-1, 7-diaminoheptane (GC7) suppressed the intracellular ROS levels. After blocking the EMT, administration of GC7 or N-acetyl-L-cysteine did not reduce cell migration further. Based on the experimental data, we concluded that inhibition of eIF5A2 alters progression of the EMT to decrease the invasion and metastasis of HCC cells via ROS-related pathways.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Movimiento Celular , Neoplasias Hepáticas/metabolismo , Factores de Iniciación de Péptidos/metabolismo , Proteínas de Unión al ARN/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Acetilcisteína/farmacología , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Guanina/análogos & derivados , Guanina/farmacología , Células Hep G2 , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Invasividad Neoplásica , Factores de Iniciación de Péptidos/genética , Interferencia de ARN , Proteínas de Unión al ARN/genética , Transducción de Señal , Factor 5A Eucariótico de Iniciación de Traducción
20.
Comb Chem High Throughput Screen ; 18(5): 514-23, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25924659

RESUMEN

Rat renal tubular epithelial cell (RTEC) cultured with high glucose has been used to observe the protective effect of Ginkgo biloba extract (GBE) against diabetic nephropathy (DN). The compounds in GBE binding with cell membrane or entering into cell are still unknown, which may be potential bioactive components. In this paper, a powerful method for screening and analyzing the potential bioactive components from GBE was developed using cell extraction coupled with high performance liquid chromatography tandem mass spectrometry (LC-MS/MS). 8 prototype compounds and 5 metabolites were obtained, among which 6 prototype compounds and 1 metabolite were identified or tentatively characterized as rutin, bilobalide, ginkgolide B, ginkgolide C, genkwanin, apigenin and diosmetin by comparing their retention times and MS spectra with those of authentic standards or literature data. The 6 prototype compounds were further quantitatively analyzed using electrospray ionization in negative mode multiple reaction monitoring (MRM). The results showed that high glucose changed the Tmax, MRT(0-t), Cmax and AUC(0-t) of all observed compounds and decreased the t1/2 of genkwanin and apigenin, significantly. The overall findings indicate that 8 prototype compounds may be the potential bioactive components of GBE with preventive effect against DN and the method of RTEC extraction coupled with LC-MS/MS technology screening method we developed is a feasible, rapid, and useful tool for screening and analyzing potential bioactive components.


Asunto(s)
Células Epiteliales/química , Ginkgo biloba/química , Túbulos Renales Proximales/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Animales , Células Cultivadas , Cromatografía Líquida de Alta Presión , Técnicas Químicas Combinatorias , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Ensayos Analíticos de Alto Rendimiento , Túbulos Renales Proximales/efectos de los fármacos , Túbulos Renales Proximales/metabolismo , Extractos Vegetales/farmacología , Ratas , Espectrometría de Masas en Tándem
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