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2.
Int J Nanomedicine ; 14: 8989-9006, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819414

RESUMO

Objective: The objective of this study was to develop magnetic embolic microspheres that could be visualized by clinical magnetic resonance imaging (MRI) scanners aiming to improve the efficiency and safety of embolotherapy. Methods and discussion: Magnetic ferrite nanoclusters (FNs) were synthesized with microwave-assisted solvothermal method, and their morphology, particle size, crystalline structure, magnetic properties as well as T2 relaxivity were characterized to confirm the feasibility of FNs as an MRI probe. Magnetic polymer microspheres (FNMs) were then produced by inverse suspension polymerization with FNs embedded inside. The physicochemical and mechanical properties (including morphology, particle size, infrared spectra, elasticity, etc.) of FNMs were investigated, and the magnetic properties and MRI detectable properties of FNMs were also assayed by vibrating sample magnetometer and MRI scanners. Favorable biocompatibility and long-term MRI detectability of FNMs were then studied in mice by subcutaneous injection. FNMs were further used to embolize rabbits' kidneys to evaluate the embolic property and detectability by MRI. Conclusion: FNMs could serve as a promising MRI-visualized embolic material for embolotherapy in the future.


Assuntos
Embolização Terapêutica , Compostos Férricos/química , Imagem por Ressonância Magnética , Magnetismo , Microesferas , Nanopartículas/química , Polímeros/química , Animais , Difusão Dinâmica da Luz , Elasticidade , Feminino , Ferro/metabolismo , Rim/diagnóstico por imagem , Rim/patologia , Masculino , Camundongos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Coelhos
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(4): 471-477, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31642221

RESUMO

OBJECTIVE: To determinethe diagnostic valuesand reliabilityof cardiac magnetic resonance tissue tracking (CMR-TT) derived two-dimensional(2D) and three-dimensional(3D) strains in assessing experimental autoimmunity myocarditis (EAM) in rats. METHODS: 20 Lewis rats were randomly divided into model and control groups. The animal model of autoimmune myocarditis was induced by injecting porcine cardiac myosin into the footpads of the rats.On day 35, all of the rats were examined using the 7.0T CMR cine scan. The cardiac function and global strain of the left ventricular of the rats were analyzed with specific cardiac post-processing. The rats were then sacrificed and myocardial samples were taken and stained with HE and Masson. The diagnostic values of the strain parameters were assessed by receiver operating characteristic (ROC) curves with the pathological results as diagnostic criteria.The reliability of the strain parameters were tested using interclass correlation coefficient (ICC), coefficients of variation (CV) and Bland-Altman. RESULTS: No abnormal pathological changes in myocardial cells were found in the control group. Myocarditis was successfully induced in all of the rats in the model group, showing myocardial fiber arrangement disorder, degeneration, necrosis, inflammatory cell infiltration and interstitial fibrosis. The ROC showed that 2D global strain parameters possessed higher diagnostic values than 3D strain parameters. The 2D had an area under the curve (AUC) of 0.96 in global circumferential strain (GCS), 0.95 in global radial strain (GRS), and 0.90 in global longitudinal strain (GLS), compared with 0.87 GCS, 0.85 GRS, and 0.77 GLS in the 3D, respectively.The reliability of the 2D strain parameters was high, except for inter-observer 2D GRS(ICC=0.893). The 3D strain parameters had lower reliability (ICCs:0.421-0.79) than the 2D strain parameters (ICCs:0.893-0.986). CONCLUSION: The diagnostic values of 2D strain parameters are higher than 3D strain parameters in diagnosing myocarditis.


Assuntos
Doenças Autoimunes/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Miocardite/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Distribuição Aleatória , Ratos , Ratos Endogâmicos Lew , Reprodutibilidade dos Testes , Suínos , Função Ventricular Esquerda
4.
Int J Pharm ; 527(1-2): 31-41, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28487188

RESUMO

To develop embolic microspheres with MRI detectability, superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized and mixed with monomer of acrylic acid to prepare SPIONs-loaded polymerized microspheres (SPMs) by inverse suspension polymerization method. The SPMs were evaluated for the ability of embolization by investigating the morphology, particle size, elasticity and renal arterial embolization to rabbits. Meanwhile, the loading of SPIONs was verified by optical microscope, transmission electron microscope, Fourier transform infrared spectrum, vibrating sample magnetometer, X-ray diffraction and X-ray photoelectron spectroscopy, and the content of SPIONs in SPMs was measured quantitatively. Furthermore, the MRI detectability of SPMs was testified in gel phantom, mice and rabbits respectively by a clinical 3.0T MRI scanner. The results revealed the SPMs were potential MRI detectable embolic microspheres for improving the effectiveness and safety of embolotherapy in the future.


Assuntos
Resinas Acrílicas/química , Embolização Terapêutica , Nanopartículas de Magnetita/química , Microesferas , Animais , Imagem por Ressonância Magnética , Masculino , Camundongos , Coelhos
5.
Int J Toxicol ; 33(2): 98-105, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24563414

RESUMO

Toxicity is one of the major reasons for failure in drug development. Zebrafish, as an ideal vertebrate model, could also be used to evaluate drug toxicity. In this study, we aimed to show the predictability and highlight novel findings of toxicity in zebrafish model. Seven anticancer compounds, including triptolide (TP), gambogic acid (GA), mycophenolic acid (MPA), curcumin, auranofin, thalidomide, and taxol, were assessed in zebrafish for their toxicity. Three compounds (GA, TP, and taxol) showed highest acute lethality, with 50% lethal concentration ≈ 1 µmol/L. Missing tails, severe pericardial edema, and enlarged yolk sacs were observed in MPA-treated embryos. The development of pectoral fins was severely disturbed in thalidomide-, GA-, and TP-treated embryos. Bradycardia was observed in MPA- and thalidomide-treated groups. Our findings suggested that the zebrafish are a good model for toxicity assessment of anticancer compounds.


Assuntos
Antineoplásicos/toxicidade , Peixe-Zebra/fisiologia , Animais , Doenças Cardiovasculares/induzido quimicamente , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Larva/anatomia & histologia , Larva/efeitos dos fármacos , Dose Letal Mediana , Teratogênios/toxicidade
6.
Zhongguo Zhen Jiu ; 30(11): 949-51, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21246856

RESUMO

The loss of cultural information transmission, inaccurate of translation or misunderstanding of the whole sentence in acupuncture translation are illustrated in this article. It suggests that these mistakes should be paid attention to and avoided; simultaneously, the solutions are stated so as to insure the accurate transmission of acupuncture.


Assuntos
Terapia por Acupuntura , Terminologia como Assunto , Traduções , Cultura
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(5): 681-4, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-16128062

RESUMO

Nano-diamond was synthesized by TNT/RDX explosives detonation in a steel chamber and characterized by X-ray diffraction (XRD), laser Raman spectroscopy, and infrared spectroscopy. XRD results indicate that nano-diamond has cubic diamond structure. The parameter of unit cell of nano-diamond is 0.359 23 nm and is 0.72% larger than that of the bulk diamond. The high-density defects and other impurity atoms in the nano-diamond structure may lead to the large lattice constant. The examination results of Raman spectra show that the Raman band is broader and shifts to l ow frequency by 3 cm(-1), because the size of nano-diamond reaches nanometer order. There is little graphite in the nano-diamond. There are two peaks in FTIR of the nano-diamond, which are characteristic peaks of diamond at 1 262 and 1 134 cm(-1). Besides these two peaks, there are six peaks at 3 422, 1 643, 2 971, 2 930, 2 857 and 1 788 cm(-1) respectively. The FTIR bands at 2 930 and 2 857 cm(-1) are the antisymmetrical and symmetrical stretch vibration absorption spectra of CH2 respectively. The 3 422 cm(-1) is the stretch vibration absorption peak of O-H. The 1 634 cm(-1) confirms that there are H2O in the nano-diamond. The 2 971 cm(-1) is the antisymmetrical stretch vibration absorption peak of CH3. The 1 788 cm(-1) is the stretch vibration absorption peak of C=O. These indicate that there are H and O elements in the nano-diamond. From the mechanism of the nano-diamond, the authors discuss the reason for the vibration absorption peaks of O-H, CH2, CH3, and C=O, existing in the FTIR of the nano-diamond.


Assuntos
Diamante/química , Substâncias Explosivas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Algoritmos , Cristalização , Nanoestruturas/química , Triazinas/química , Trinitrotolueno/química , Difração de Raios X
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(1): 54-7, 2005 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15852818

RESUMO

The nano-graphite powder synthesized by the detonation of explosives with negative oxygen balance is a new powder material with potential applications. In this work, the preparation of nano-graphite powder in steel chamber by pure TNT (trinitrotoluene) explosives has been introduced. In the synthesis process, the protective gases in the steel chamber are N2, CO2 and Ar, and the pressure is 0.25-2 atm. Raman spectrum of the nano-graphite was measured. The characteristic Raman band assigned to sp2 of graphite has been observed at about 1 585 cm(-1) with half-peak width of 22 cm(-1). The peak shifted to a higher frequency by 5 cm(-1) compared with that of bulk graphite. The authors explain this blue shift phenomenon by size effect. The average size of nanographite from Raman measurement is 2.97-3.97 nm. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to measure the structure and particle size of the nano-graphite. The crystallite size of nano-graphite estimated from XRD andTEM are 2.58 nm (acid untreated) and 1.86 nm (acid treated) respectively, which is in accord with the results of the measurement approximately.


Assuntos
Substâncias Explosivas/química , Grafite/química , Análise Espectral Raman , Trinitrotolueno/química , Argônio/química , Dióxido de Carbono/química , Cristalização , Grafite/síntese química , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Nitrogênio/química , Tamanho da Partícula , Pós , Difração de Raios X
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