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1.
Analyst ; 144(20): 5965-5970, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31464302

RESUMO

Hydrogen peroxide (H2O2) plays crucial roles in immunological processes and has been revealed to be closely linked to the hypoxic-ischemic process. Thus, it is important to develop a reliable method for monitoring H2O2 in hypoxic-ischemic brain injury (HIBI). To achieve this, we report on a rationally designed fluorene-based ratiometric two-photon fluorescent probe for H2O2, i.e., FH2O2. The probe and fluorophore were tested under either one- or two-photon modes, respectively. After reacting with H2O2, the relative emission intensity ratio at wavelengths of 390-465 (Fblue) and 500-550 nm (Fyellow) of FH2O2 had a 6.5-fold increase (Fyellow/Fblue) within 40 min, and the maximal two-photon active cross-section value was detected as 66 GM at a wavelength of 750 nm. The probe exhibited high selectivity, low cytotoxicity, high sensitivity with a detection limit of 0.57 µM, and adequate photostability. After confirming satisfactory sensing performance of the probe in vitro, we were able to monitor H2O2in situ in mice with HIBI via two-photon microscopy, which could provide a potential method for clinical diagnosis during the neonatal HIBI process.


Assuntos
Lesões Encefálicas/metabolismo , Isquemia Encefálica/metabolismo , Corantes Fluorescentes/química , Peróxido de Hidrogênio/metabolismo , Imagem Molecular/métodos , Fótons , Animais , Células HeLa , Humanos
2.
ACS Omega ; 9(30): 32481-32501, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39100303

RESUMO

This article used Carboniferous-Permian coals from the Jungar, Hedong, and Weibei Coalfields in the east of the Ordos Basin as research samples. Characteristics of coal quality, petrology, mineralogy, and geochemistry were analyzed by proximate analysis, inductively coupled plasma mass spectrometry, X-ray fluorescence spectroscopy, X-ray diffraction analysis, scanning electron microscopy-energy spectrum analysis, and incident light microscope. The enrichment regulations, distribution patterns, and occurrences of REY (rare earth element and yttrium) in coal under different geological conditions were compared. Geological significance and the influence of REY were then discussed. The average REY of Permian coal in the eastern margin of the basin is 127.9 µg/g, CC = 1.87, and the average REY of Carboniferous coal is 117.49 µg/g, CC = 1.72, which are within the normal enrichment range. The inorganic affinity of REYs in the study area is strong and mainly occurs in clay minerals and detrital phosphates and correlates well with LREY. The Permian coal sedimentary environment is more oxidized than the Taiyuan formation, and the Carboniferous coal sedimentary environment is noticeably more affected by marine water. With an increasing degree of coalification, the concentration of rare earth elements (REE) in high-rank coal vitrinite is lower than that in inertinite. In contrast, the concentration of REEs in low-rank coal is the opposite. This is because the oxygen-containing functional groups that can combine with REEs in vitrinite reduce significantly, resulting in the loss of trace elements into other forms. The provenance of the northern and central regions of the study area is mainly sedimentary rocks, granite, alkaline basalt, and continental tholeiite, while the southern region is mainly granite and sedimentary rocks.

3.
Phytochem Anal ; 24(6): 623-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23722924

RESUMO

INTRODUCTION: Camptothecin, a widely used natural anti-cancer drug, is difficult to extract and purify effectively from plants. OBJECTIVE: To develop new and highly efficient extraction and purification methods for analysis and production of camptothecin from leaves and fruits of Camptotheca acuminata and Nothapodytes pittosporoides roots. METHODS: Dried materials were loaded in empty columns with fivefold 60% ethanol for leaves or 70% ethanol for fruits of C. acumnata, and sixfold 70% ethanol for N. pittosporoides roots. The columns were eluted with the same solvents at room temperature. Eluent was collected as extraction solution. Extraction solution from leaves and fruits of C. acuminata was vacuum-evaporated to remove ethanol, precipitated at pH 8.0 to remove alkaline insolubles and fractionated with chloroform at pH 3.0, which yields a crude product with 70% purity. Extraction solution from N. pittosporoides roots was concentrated to 1/10 volume and precipitated at pH 3.0, which yields a crude product with 60% purity. All crude products were purified by crystallisation. All steps were monitored by HPLC. RESULTS: Camptothecin was extracted from the three plant materials at a 98% rate with 15- or 18-fold solvent for content analysis, or at a 97% rate with five- or sixfold solvent for production. All crude products were purified to 98%. The overall recovery rates of camptothecin from plant materials to purified products reached 92% or higher. CONCLUSION: The new procedures are simple and highly efficient, and have multiple advantages for quantitative analysis and large production of camptothecin from plants.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Camptotheca/química , Camptotecina/isolamento & purificação , Cromatografia/métodos , Cromatografia/normas , Folhas de Planta/química , Raízes de Plantas/química
4.
Nutrients ; 15(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36678243

RESUMO

A frequent chronic liver condition across the world is nonalcoholic fatty liver disease (NAFLD). Oxidative stress caused by lipid accumulation is generally considered to be the main cause of NAFLD. Anthocyanins can effectively inhibit the production of reactive oxygen species and improve oxidative stress. In this work, six major anthocyanins were separated from purple corncob by semi-preparative liquid chromatography. The effects of the 6 kinds of anthocyanins against NAFLD were investigated using a free fatty acid (FFA)-induced cell model. The results showed that peonidin 3-O-glucoside (P3G) can significantly reduce lipid accumulation in the NAFLD cell model. The treatment with P3G also inhibited oxidative stress via inhibiting the excessive production of reactive oxygen species and superoxide anion, increasing glutathione levels, and enhancing the activities of SOD, GPX, and CAT. Further studies unveiled that treatment with P3G not only alleviated inflammation but also improved the depletion of mitochondrial content and damage of the mitochondrial electron transfer chain developed concomitantly in the cell model. P3G upregulated transcription factor EB (TFEB)-mediated lysosomal function and activated the peroxisome proliferator-activated receptor alpha (PPARα)-mediated peroxisomal lipid oxidation by interacting with PPARα possibly. Overall, this study added to our understanding of the protective effects of purple corn anthocyanins against NAFLD and offered suggestions for developing functional foods containing these anthocyanins.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Hepatopatia Gordurosa não Alcoólica/etiologia , Antocianinas/farmacologia , Antocianinas/metabolismo , Fígado/metabolismo , Zea mays/metabolismo , Espécies Reativas de Oxigênio/metabolismo , PPAR alfa/metabolismo , Glucosídeos/farmacologia , Estresse Oxidativo , Inflamação/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Lisossomos/metabolismo
5.
ACS Omega ; 7(16): 13557-13576, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35559164

RESUMO

The geochemical characteristics of trace elements in Carboniferous-Permian coal and gangue in the Yangcheng mining area in Qinshui Basin, a large Carboniferous-Permian coalfield in China, were studied by inductively coupled plasma mass spectrometry (ICP-MS), and their geological significance was discussed. The results show that the content of trace elements in late Paleozoic coal in the Yangcheng mining area is depleted, except for slight enrichment of Li. Except for Li, Co, and Mo, the content of trace elements in the gangue was higher than that in the coal. The content of rare earth elements in gangue (324.28 µg/g) is much higher than that in coal (66.22 µg/g). The rare earth elements (REY) content in the coal in the Shanxi Formation (93.88 µg/g) is slightly higher than that in the Taiyuan Formation (66.19 µg/g). The mean values of δEu and δCe are 0.71 and 0.94, respectively. Except for the YIC3-1 curve of the Shanxi Formation, which is obviously convex and shows a positive Eu anomaly, the REY distribution patterns of the remaining samples are similar, showing the characteristics of light rare earth elements (LREY) enrichment and heavy rare earth elements (HREY) depletion. The Carboniferous-Permian coal-forming environment in the Yangcheng mining area is in an anoxic-reducing, warm, humid, and brackish water sedimentary environment. The paleosalinity and paleotemperature of the Shanxi coal formation are higher than those of the Taiyuan Formation, which is more inclined to be a reducing environment. The provenance of Carboniferous-Permian coal in the Yangcheng mining area is mainly derived from acidic sedimentary rocks of the upper crust of the post-Archaean, mixed with a small amount of granite, alkaline basalt, and oceanic tholeiite. The tectonic setting of the provenance is mainly an active continental margin related to a continental island arc mixed with an oceanic island arc and a passive continental margin tectonic setting.

6.
ACS Omega ; 6(27): 17660-17673, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34278151

RESUMO

The Qinshui basin is an important coal-accumulating basin in China, and its Late Paleozoic coal is an important source rock of coalbed methane in the basin. Its thermal evolution and gas generation characteristics determined the grade of coalbed methane resources, especially the coal measure free gas resources in the basin. Late Paleozoic coal samples were collected for organic geochemical analysis, a high-volatile bituminous coal was used for hydrous pyrolysis, to propose the thermal evolution characteristics, gas generation characteristics, thermal evolution, and free gas accumulation model, and the Ordos Basin is compared. The results show that the variation trends of various geochemical parameters are different with the increase in R o. Hydrous pyrolysis shows that the gas production potential of coal is excellent. The gases produced consist mainly of CH4, C2-, CO2, and H2. C2- is produced only before the simulated temperature of 550 °C, and oil is produced only before the temperature of 500 °C. The thermal evolution stages can be divided into the immature stage, symbiosis stage, wet gas stage, and dry gas stage, and the symbiosis stage can be divided into the preliminary stage and mainly gas stage. R o, T max, (2+3)MP/(1+9)MP, saturated+arene, V daf, and H/C can be used as indicators of the thermal evolution stages. On the plane, the distribution of thermal evolution stages of the Shanxi Formation and the Taiyuan Formation is very alike. The gas generating strength of the Taiyuan Formation is higher than that of the Shanxi Formation. The gas generating strength in the north of the Taiyuan Formation is higher, while that in the south of the Shanxi Formation is higher. The second gas generation stage has a good spatio-temporal configuration relationship with accumulation factors, and the gas production is large, which is beneficial to the enrichment of the coal measure free gas resources. Relatively, the Ordos Basin has better prospects for exploration and development.

7.
Food Funct ; 12(16): 7298-7309, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34169953

RESUMO

Atherosclerosis, the major cause of cardiovascular disease, is a chronic inflammatory disease. The anti-inflammatory effect of certain polyphenols has been recognized. Active polyphenols were extracted from millet shells (MSPs), and their main components including 3-hydroxybenzylhydrazine, luteolin-3',7-diglucoside, N-acetyltyramine, p-coumaric acid, vanillin, sinapic acid, ferulic acid and isophorone exhibited the anti-atherosclerotic potential in vitro. To explore the anti-atherosclerotic activity of MSPs in vivo, a classic atherosclerosis model was constructed in ApoE-/- mice fed with a high-fat diet. The results showed that MSPs effectively inhibited the development of atherosclerotic plaques in the aorta and reduced the levels of lipopolysaccharide (LPS) and inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß). A further study found that the expression of tight junction proteins (occludin, zona occludens-1 and claudin1) was obviously up-regulated in the MSPs-treated group at the mRNA and protein levels. Interestingly, MSPs significantly changed the structure of gut microbiota in ApoE-/- mice with a high-fat diet, which is characterized by the enriched Oscillospira and Ruminococcus, and the abridged Allobaculum at the genus level. Collectively, these results suggest that MSPs regulate the integrity of the gut barrier and the structure of the gut microbiota, ultimately inhibiting the development of atherosclerotic plaques. This study provides new insights into the potential cardiovascular protective effects induced by millet shell polyphenols.


Assuntos
Aterosclerose/prevenção & controle , Dieta Hiperlipídica , Mucosa Gástrica/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Milhetes/metabolismo , Polifenóis/farmacologia , Animais , Apolipoproteínas E , Aterosclerose/metabolismo , Modelos Animais de Doenças , Mucosa Gástrica/efeitos dos fármacos , Masculino , Camundongos , Polifenóis/metabolismo , Proteínas de Junções Íntimas/metabolismo
8.
Food Chem ; 145: 542-8, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24128512

RESUMO

Citrus grandis Tomentosa is widely used in traditional Chinese medicine and health foods. Its functional components include volatiles, flavonoids and polysaccharides which cannot be effectively extracted through traditional methods. A column chromatographic extraction with gradient elution was developed for one-step extraction of all bioactive substances from C. grandis. Dried material was loaded into a column with petroleum ether: ethanol (8:2, PE) and sequentially eluted with 2-fold PE, 3-fold ethanol: water (6:4) and 8-fold water. The elutes was separated into an ether fraction containing volatiles and an ethanol-water fraction containing flavonoids and polysaccharides. The later was separated into flavonoids and polysaccharides by 80% ethanol precipitation of polysaccharides. Through this procedure, volatiles, flavonoids and polysaccharides in C. grandis were simultaneously extracted at 98% extraction rates and simply separated at higher than 95% recovery rates. The method provides a simple and high-efficient extraction and separation of wide range bioactive substances.


Assuntos
Cromatografia/métodos , Citrus/química , Flavonoides/análise , Polissacarídeos/análise , Compostos Orgânicos Voláteis/análise , Cromatografia Líquida de Alta Pressão , Cicloexenos/análise , Análise de Alimentos , Limoneno , Extratos Vegetais/análise , Terpenos/análise
9.
Biochem Pharmacol ; 82(7): 701-12, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21763293

RESUMO

Abscisic acid (ABA) is an important phytohormone that regulates plant growth, development, dormancy and stress responses. Recently, it was discovered that ABA is produced by a wide range of animals including sponges (Axinella polypoides), hydroids (Eudendrium racemosum), human parasites (Toxoplasma gondii), and by various mammalian tissues and cells (leukocytes, pancreatic cells, and mesenchymal stem cells). ABA is a universal signaling molecule that stimulates diverse functions in animals through a signaling pathway that is remarkably similar to that used by plants; this pathway involves the sequential binding of ABA to a membrane receptor and the activation of ADP-ribose cyclase, which results in the overproduction of the intracellular cyclic ADP-ribose and an increase in intracellular Ca²âº concentrations. ABA stimulates the stress response (heat and light) in animal cells, immune responses in leukocytes, insulin release from pancreatic ß cells, and the expansion of mesenchymal and colon stem cells. ABA also inhibits the growth and induces the differentiation of cancer cells. Unlike some drugs that act as cell killers, ABA, when functioning as a growth regulator, does not have significant toxic side effects on animal cells. Research indicated that ABA is an endogenous immune regulator in animals and has potential medicinal applications for several human diseases. This article summarizes recent advances involving the discovery, signaling pathways and functions of ABA in animals.


Assuntos
Ácido Abscísico/fisiologia , Reguladores de Crescimento de Plantas/fisiologia , Ácido Abscísico/farmacologia , Ácido Abscísico/uso terapêutico , Animais , Aterosclerose/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Granulócitos/metabolismo , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Ilhotas Pancreáticas/metabolismo , Microglia/metabolismo , Monócitos/metabolismo , Neoplasias/tratamento farmacológico , Fitoterapia , Reguladores de Crescimento de Plantas/farmacologia , Transdução de Sinais , Células-Tronco/metabolismo
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