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1.
J Mater Chem B ; 11(3): 640-647, 2023 01 18.
Article in English | MEDLINE | ID: mdl-36538007

ABSTRACT

Composites have been widely applied in various industries and are beneficial in attaining complicated functionalities. Particularly, for dental fiber posts or orthopedic implants, the composites should have excellent mechanical properties and good imaging effects for visualization in vivo. The traditional method to improve mechanical strength and visibility by adding reinforcing fillers and radiopacifiers is complicated and has poor distributions and long production times. Hence, fabricating an integrated reinforced filler with radiopacity is of considerable economic and social significance. After ball-milling and sintering quartz fiber (QF) and bismuth trioxide (Bi2O3), a multifunctional filler (QF-Bi2SiO5) is fabricated to impart excellent flexural strengths and high X-ray imaging qualities to the composites. A composite made of epoxy resin (EP) and QF-Bi2SiO5 has a high bending strength (126.87 ± 6.78 MPa) and bending modulus (3649.31 ± 343.87 MPa), which are attributed to the tight mechanical interlock between EP and micro/nano structures of QF-Bi2SiO5. The QF-Bi2SiO5/EP composite shows good X-ray imaging quality owing to the Bi2SiO5 crystal. Furthermore, the mechanical and imaging performances of various composites with commercial fillers were compared with that of the QF-Bi2SiO5/EP composite. No filler was found that can perform both functions as well as QF-Bi2SiO5. Hence, the fabricated composites containing micro/nano structured QF-Bi2SiO5 fillers have the potential to be used in a variety of fields requiring mechanical strength and X-ray imaging capability.


Subject(s)
Composite Resins , Flexural Strength , Quartz , Epoxy Resins , X-Rays , Materials Testing , Surface Properties , Dental Materials
2.
J Agric Food Chem ; 65(9): 2000-2007, 2017 Mar 08.
Article in English | MEDLINE | ID: mdl-28198625

ABSTRACT

N-Nitrosodiethylamine (DEN) exists as a food additive in cheddar cheese, processed meats, beer, water, and so forth. It is a potent hepatocarcinogen in animals and humans. Curcumin as a natural dietary compound decreased DEN-induced hepatocarcinogenesis in this research. According to the histopathological examination of liver tissues and biomarker detection in serum and livers, it was demonstrated that curcumin attenuated DEN-induced hepatocarcinogenesis through parts of regulating the oxidant stress enzymes (T-SOD and CAT), liver function (ALT and AST) and LDHA, AFP level, and COX-2/PGE2 pathway. Furthermore, curcumin attenuated metabolic disorders via increasing concentration of glucose and fructose, and decreasing levels of glycine and proline, and mRNA expression of GLUT1, PKM and FASN. Docking study indicated that curcumin presented strong affinity with key metabolism enzymes such as GLUT1, PKM, FASN and LDHA. There were a number of amino acid residues involved in curcumin-targeting enzymes of hydrogen bonds and hydrophobic interactions. All in all, curcumin exhibited a potent liver protective agent inhibiting chemically induced liver injury through suppressing liver cellular metabolism in the prospective application.


Subject(s)
Chemical and Drug Induced Liver Injury/drug therapy , Curcumin/administration & dosage , Diethylnitrosamine/toxicity , Animals , Chemical and Drug Induced Liver Injury/enzymology , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/genetics , Humans , Liver/drug effects , Liver/enzymology , Male , Metabolomics , Mice , Oxidative Stress/drug effects
3.
Mol Carcinog ; 56(5): 1405-1413, 2017 05.
Article in English | MEDLINE | ID: mdl-27991692

ABSTRACT

Lung cancer is the foremost cause of cancer mortality and a growing economic burden worldwide. Rhizoma paridis saponins (RPS) have been reported to exhibit potential anti-tumor effects on many kinds of tumor models. The present study was designed to investigate the mechanism-based chemopreventive nature of RPS against DEN-induced lung carcinogenesis in Kunming mice. As a result, the treatment with RPS reduced the severity of pulmonary histopathology. The mechanism of its antitumor effect involved in (a) reducing oxidative stress injury through up-regulating activities of CAT and SOD; (b) down-regulating the levels of inflammatory factors, like TNF-α, IL6, COX-2, and PGE2; (c) activation of caspase-3 and up-regulating the pro-apoptotic protein Bax; (d) decreasing the expression of PCNA; (e) depressing the expression of cancer stem cells marker CD133; (f) suppressing aberrant expression of cytokeratin 8 and 18; and (g) inhibiting EGFR/ PI3 K/Akt, EGFR/Ras/Erk and NF-κB pathways. Taken together, RPS would be a potent agent inhibiting lung tumor in the future.


Subject(s)
Liliales/chemistry , Lung Neoplasms/drug therapy , Saponins/pharmacology , Animals , Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Cell Proliferation/drug effects , Diethylnitrosamine/toxicity , ErbB Receptors/metabolism , Lung Neoplasms/chemically induced , Lung Neoplasms/pathology , Male , Mice , Neoplasms, Experimental/drug therapy , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/pathology , Oxidative Stress/drug effects , Rhizome/chemistry
4.
Environ Toxicol ; 32(1): 99-108, 2017 Jan.
Article in English | MEDLINE | ID: mdl-26590097

ABSTRACT

Rhizoma Paridis saponins (RPS) is a traditional Chinese medicine (TCM) from the plant Paris polyphylla var. yunnanensis (Fr.) Hand.-Mazz. Despite its potentially clinical utility such as anticancer and anti-inflammation, it has slight side effects and toxicity as previous report. In this work, 90-day administration of RPS induced liver injury. 1 H-NMR- and GC/MS-based metabonomic analyses in conjunction with histopathological examinations, blood biochemistry and hepatic phase I and II enzymes assays were performed to evaluate the toxic mechanisms of RPS induced in rats. As a result, oral administration of RPS possessed certain liver toxicity in SD rats. 1 H-NMR and GC/MS data indicated that RPS inhibited the oxidation of fatty acids, glycolysis, and TCA cycle pathway, and disturbed glycine, serine, and threonine metabolism. Low expression of TG, T-CHO, and LDL-C and high levels of ALT and AST indicated that chronic exposure to RPS caused hepatocyte damage, synthesis dysfunction, and transportation failure of lipoproteins. In addition, RPS downregulated the mRNA levels of CYP1A2, CYP2E1, and UGTs. In conclusion, we used metabonomics approach to study the toxicity of RPS for the first time. This research demonstrated that metabonomics method was a promising tool to study and diagnose TCM-induced toxicity. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 99-108, 2017.


Subject(s)
Chemical and Drug Induced Liver Injury/metabolism , Saponins/toxicity , Animals , Chemical and Drug Induced Liver Injury/enzymology , Chemical and Drug Induced Liver Injury/pathology , Gas Chromatography-Mass Spectrometry , Liver/drug effects , Liver/enzymology , Liver/pathology , Liver Function Tests , Male , Medicine, Chinese Traditional , Metabolomics , Rats , Rats, Wistar
5.
Chem Biol Interact ; 256: 55-63, 2016 Aug 25.
Article in English | MEDLINE | ID: mdl-27369806

ABSTRACT

Murine H22 hepatocarcinoma model is so popular to be used for the preclinical anticancer candidate's evaluation. However, the metabolic biomarkers of this model were not identified. Meanwhile, Rhizoma Paridis saponins (RPS) as natural products have been found to show strong antitumor activity, while its anti-cancer mechanism is not clear. To search for potential metabolite biomarkers of this model, serum metabonomics approach was applied to detect the variation of metabolite biomarkers and the related metabolism genes and signaling pathway were used to deduce the antitumor mechanisms of RPS. As a result, ten serum metabolites were identified in twenty-four mice including healthy mice, non-treated cancer mice, RPS-treated cancer mice and RPS-treated healthy mice. RPS significantly decreased tumor weight correlates to down-regulating lactate, acetate, N-acetyl amino acid and glutamine signals (p < 0.05), which were marked metabolites screened according to the very important person (VIP), loading plot and receiver operating characteristic curve (ROC) tests. For the analysis of metabolic enzyme related genes, RPS reversed the aerobic glycolysis through activating tumor suppressor p53 and PTEN, and suppressed FASN to inhibit lipogenesis. What's more, RPS repressed Myc and GLS expression and decreased glutamine level. The regulating PI3K/Akt/mTOR and HIF-1α/Myc/Ras networks also participated in these metabolic changes. Taken together, RPS suppressed ATP product made the tumor growth slow, which indicated a good anti-cancer effect and new angle for understanding the mechanism of RPS. In conclusion, this study demonstrated that the utility of (1)H NMR metabolic profiles taken together with tumor weight and viscera index was a promising screening tool for evaluating the antitumor effect of candidates. In addition, RPS was a potent anticancer agent through inhibiting cancer cellular metabolism to suppress proliferation in hepatoma H22 tumor murine, which promoted the application of RPS in the future.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Drugs, Chinese Herbal/therapeutic use , Liver Neoplasms/blood , Liver Neoplasms/drug therapy , Liver/drug effects , Metabolomics/methods , Saponins/therapeutic use , Animals , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Biomarkers, Tumor/blood , Biomarkers, Tumor/metabolism , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Female , Liver/metabolism , Liver/pathology , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Magnoliopsida/chemistry , Mice , Rhizome/chemistry , Saponins/chemistry , Saponins/pharmacology
6.
J Agric Food Chem ; 64(13): 2765-71, 2016 Apr 06.
Article in English | MEDLINE | ID: mdl-26978516

ABSTRACT

Curcumin is the major active component of turmeric and widely used as a spice and coloring agent in food. However, its safety evaluation has been little investigated. To evaluate the 90-day subchronic toxicity of curcumin in rats, its general observation, clinical biochemistry, pathology, and metabolomics were evaluated. The results showed that curcumin induced liver injury through the generation of the overexpression of reactive oxygen species (ROS) and pro-inflammatory cytokines IL-6 and the decreases of the levels of antioxidant enzyme SOD and detoxified enzyme GST. Meanwhile, for the self-protection of rats, curcumin treatment activated the transcription of Nrf-2 and elevated the expression of HO-1 to reduce tissue damage. Furthermore, curcumin significantly increased key mRNA levels of HK2, PKM2, LDHA, CES, Cpt1, Cpt2, FASN, and ATP5b and decreased levels of GLUT2 and ACC1 to enhance glycolysis and inhibit lipid metabolism and TCA cycle. Therefore, overdose or long-term intake of curcumin could initiate the unbalanced state of bodies through oxidative stress, inflammation, and metabolic disorders, which induces liver injury. Intermittent administration of curcumin is necessary in our daily lives.


Subject(s)
Antioxidants , Curcuma/chemistry , Curcumin , Reactive Oxygen Species/analysis , Spices/analysis , Animals , Antioxidants/administration & dosage , Antioxidants/chemistry , Antioxidants/pharmacology , Antioxidants/toxicity , Curcumin/administration & dosage , Curcumin/chemistry , Curcumin/pharmacology , Curcumin/toxicity , Interleukin-6/metabolism , Liver/metabolism , Male , Oxidative Stress/drug effects , RNA, Messenger/drug effects , Rats
7.
Accid Anal Prev ; 95(Pt B): 395-404, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26463880

ABSTRACT

Road traffic accidents resulting in group deaths and injuries are often related to coach drivers' inappropriate operations and behaviors. Thus, the evaluation of coach drivers' fitness to drive is an important measure for improving the safety of public transportation. Previous related research focused on drivers' age and health condition. Comprehensive studies about commercial drivers' cognitive capacities are limited. This study developed a toolkit consisting of nine cognition measurements across driver perception/sensation, attention, and reaction. A total of 1413 licensed coach drivers in Jiangsu Province, China were investigated and tested. Results indicated that drivers with accident history within three years performed overwhelmingly worse (p<0.001) on dark adaptation, dynamic visual acuity, depth perception, attention concentration, attention span, and significantly worse (p<0.05) on reaction to complex tasks compared with drivers with clear accident records. These findings supported that in the assessment of fitness to drive, cognitive capacities are sensitive to the detection of drivers with accident proneness. We first developed a simple evaluation model based on the percentile distribution of all single measurements, which defined the normal range of "fit-to-drive" by eliminating a 5% tail of each measurement. A comprehensive evaluation model was later constructed based on the kernel principal component analysis, in which the eliminated 5% tail was calculated from on integrated index. Methods to categorizing qualified, good, and excellent coach drivers and criteria for evaluating and training Chinese coach drivers' fitness to drive were also proposed.


Subject(s)
Accidents, Traffic , Attention , Automobile Driving/psychology , Cognition , Occupations , Task Performance and Analysis , Visual Perception , Adolescent , Automobile Driving/standards , China , Depth Perception , Female , Humans , Licensure , Male , Middle Aged , Psychometrics , Safety , Transportation , Visual Acuity
8.
Pathol Res Pract ; 211(12): 948-54, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26471217

ABSTRACT

Rhizoma Paridis saponins combined with turmeric (RT) showed well anti-hepatocarcinoma activities in our previous research. The aim of this study was to investigate the progression of the biochemical response to RT and capture metabolic variations during intragastric administration of their compatibility. In the experiment, histopathological examination and (1)H NMR method were developed and validated for the metabolic profiling of RT intervention in H22 tumor growth. Data were analyzed with principal components analysis (PCA) and partial least-squares discrimination analysis (PLS-DA). As a result, Rhizoma paridis saponins (RPS) or RT induced inflammatory cell infiltration in tumors. RT also mediated the tumor microenvironment to promote anti-tumor immunity of mice. RT significantly inhibited tumor growth rate through suppressing levels of amino acids containing alanine, asparagine, glutamine, putrescine, and sarcosine, lipid compounds, and carbohydrates like myo-inositol and arabinose in the tumor tissues. In conclusion, these results uncovered unexpectedly poor nutritional conditions in the RT-treated tumor tissues whose effect was stronger than RPS's. Therefore, RT could be a novel anticancer agent that targets on cancer metabolism through starving tumors reducing viability of cancer cells.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/pathology , Curcuma , Liver Neoplasms/pathology , Plant Extracts/pharmacology , Saponins/pharmacology , Animals , Disease Models, Animal , Female , Magnetic Resonance Spectroscopy , Mice , Phytotherapy/methods , Principal Component Analysis , Rhizome
9.
Theranostics ; 5(5): 456-68, 2015.
Article in English | MEDLINE | ID: mdl-25767613

ABSTRACT

Rare-earth (RE)-doped upconversion nanocrystals (UCNCs) are deemed as the promising candidates of luminescent nanoprobe for biological imaging and labeling. A number of methods have been used for the fabrication of UCNCs, but their assembly into porous architectures with desired size, shape and crystallographic phase remains a long-term challenging task. Here we report a facile, anion-induced hydrothermal oriented-explosive method to simultaneously control size, shape and phase of porous UCNCs. Our results confirmed the anion-induced hydrothermal oriented-explosion porous structure, size and phase transition for the cubic/hexagonal phase of NaLuF4 and NaGdF4 nanocrystals with various sizes and shapes. This general method is very important not only for successfully preparing lanthanide doped porous UCNCs, but also for clarifying the formation process of porous UCNCs in the hydrothermal system. The synthesized UCNCs were used for in vitro and in vivo CT imaging, and could be acted as the potential CT contrast agents.


Subject(s)
Chemical Phenomena , Contrast Media/administration & dosage , Contrast Media/chemistry , Lanthanoid Series Elements/administration & dosage , Lanthanoid Series Elements/chemistry , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Animals , Female , Mice, Nude , Tomography, X-Ray Computed
10.
J Mater Chem B ; 3(19): 3948-3958, 2015 May 21.
Article in English | MEDLINE | ID: mdl-32262617

ABSTRACT

The phase transition of upconversion nanocrystals (UNs) from cubic to hexagonal structure is of fundamental importance in improving the luminescence intensity by about one or two orders of magnitudes, but the mechanism is still not well understood and efforts to completely transfer the phase from cubic to hexagonal structure remains a difficult and challenging task. Here, we describe a hydrothermal system in which an anion induces the phase transition process to give simultaneous control over the size, morphology, phase and emission properties. We first confirm that the crystal cell oriented-rotation driven by an anion in a hydrothermal system promoted the phase transition, and the energy zones figure of the phase transition from cubic to hexagonal structure has been figured out. We have successfully applied the structural mechanics finite element calculations to validate the reaction process. We have also demonstrated that porous UNs can be rationally tuned in size (down to fifteen nanometers), phase (cubic or hexagonal) and emission properties at precisely defined conditions, and were effective for in vitro and in vivo CT imaging.

11.
ACS Appl Mater Interfaces ; 7(1): 340-50, 2015 Jan 14.
Article in English | MEDLINE | ID: mdl-25490394

ABSTRACT

In this work, we developed a facile hydrothermal method for synthesis of hybrid α-Fe2O3-carbon nanotubes (CNTs) architectures (α-Fe2O3-CNTs-1 and α-Fe2O3-CNTs-2). The CNTs are in situ attached to the α-Fe2O3 submicron spheres and form three-dimensional network robust architectures. The increase in the amount of CNTs in the network α-Fe2O3-CNTs architectures will significantly enhance the cycling and rate performance, as the flexible and robust CNTs could ensure the fast electron transport pathways, enhance the electronic conductivity, and improve the structural stability of the electrode. As for pure α-Fe2O3 submicron spheres, the capacity decreased significantly and retained at 377.4 mAh g(-1) after 11 cycles, and the capacity has a slightly increasing trend at the following cycling. In contrast, the network α-Fe2O3-CNTs-2 electrode shows the most remarkable performance. At the 60th cycle, the capacity of network α-Fe2O3-CNTs-2 (764.5 mAh g(-1)) is 1.78 times than that of α-Fe2O3 submicron spheres (428.3 mAh g(-1)). The long-term cycling performance (1000 cycles) of samples at a high current density of 5 C showed that the capacity of α-Fe2O3 submicron spheres fade to ∼37.3 mAh g(-1) at the 400th cycle and gradually increased to ∼116.7 mAh g(-1) at the 1000th cycle. The capacity of network α-Fe2O3-CNTs-2 maintained at ∼220.2 mAh g(-1) before the 400th cycle, arrived at ∼326.5 mAh g(-1) in the 615th, cycle and retained this value until 1000th cycle. The network α-Fe2O3-CNTs-2 composite could significantly enhance the cycling and rate performance than pure α-Fe2O3 submicron spheres composite.

12.
Nanoscale ; 5(23): 11512-25, 2013 Dec 07.
Article in English | MEDLINE | ID: mdl-24121736

ABSTRACT

Owing to their unique photo-physical properties, rare-earth ions-doped upconversion nanoparticles (UCNPs) have attracted extensive attention in recent years. UCNPs have many special merits, such as a long luminescence lifetime, narrow emission band widths, high quantum yields and low toxicity, which allows their potential applications in bio-medical field, biological luminescent labels and drug delivery carriers. Compared with traditional fluorescence labels exited by UV (ultraviolet), such as organic dyes and quantum dots, UCNPs can transfer near-infrared (NIR) light into visible light, which is commonly called upconversion luminescence (UCL). This paper reviews the recent advances of several typical synthesis methods of UCNPs in detail as well as the fabrication and optimization of the particle morphology, and the latest advances of UCNPs for multimode imaging, surface passivation and functionalization are also described.

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