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1.
J Radiat Res ; 61(6): 920-928, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32960262

RESUMO

The aim of the study was to evaluate the clinical feasibility of a 3D-print silica bolus for nasal NK/T-cell lymphoma radiation therapy. Intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) plans were designed using an anthropomorphic head phantom with a 3D-print silica bolus and other kinds of bolus used clinically, and the surface dose was measured by a metal oxide semiconductor field-effect transistor (MOSFET) dosimeter. Four nasal NK/T patients with or without 3D-print silica bolus were treated and the nose surface dose was measured using a MOSFET dosimeter during the first treatment. Plans for the anthropomorphic head phantom with 3D-print bolus have more uniform dose and higher conformity of the planning target volume (PTV) compared to other boluses; the homogeneity index (HI) and conformity index (CI) of the VMAT plan were 0.0589 and 0.7022, respectively, and the HI and CI of the IMRT plan were 0.0550 and 0.7324, respectively. The MOSFET measurement results showed that the surface dose of the phantom with 3D-print bolus was >180 cGy, and that of patients with 3D-print bolus was higher than patients without bolus. The air gap volume between the 3D-print bolus and the surface of patients was <0.3 cc. The 3D-print silica bolus fitted well on the patient's skin, effectively reducing air gaps between bolus and patient surface. Meanwhile, the 3D-print silica bolus provided patients with higher individuation, and improved the conformity and uniformity of the PTV compared to other kinds of boluses.


Assuntos
Linfoma Extranodal de Células T-NK/radioterapia , Neoplasias Nasais/radioterapia , Impressão Tridimensional , Radioterapia de Intensidade Modulada/métodos , Radioterapia/instrumentação , Dióxido de Silício/química , Antropometria , Humanos , Órgãos em Risco/efeitos da radiação , Imagens de Fantasmas , Fótons , Radiometria , Radioterapia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Fluxo de Trabalho
2.
Biosci. j. (Online) ; 34(3): 778-789, mai/jun. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-967000

RESUMO

Usually, weak inorganic acids have been used to disperse collagen as green solvents for fabricating kinds of biomaterials all the time. However, it is an open question how much the dissolving process preserves or alters the native structure of collagen till now. Herein, we have examined the effect of three different solvents (HAc, HCl, H3PO4) on the secondary structures of collagen, based on circular dichroism (CD) spectra of collagen from 185 to 260 nm together with CDNN programs. We have found that collagen almost completely preserved its triple helical structure in the three inorganic acids at pH=3.0 or so, which demonstrated that it was the concentration of free H+ in the above three solutions whose pH was fixed at 3.0 that can maintain an proper amount of surface charge on the collagen colloidal particles and appropriately loose the three-helix structure, which can not only lead to a better dispersion behavior, but also maximize the preservation of the integrity of the collagen structure. Although the fractions of kinds of secondary structures in collagen were different from all the three solvents based on CDNN data, which gave very similar results for each other. These results was tested for the first time in this work to estimate the secondary structures for collagen in the different common inorganic acids, which provides a new avenue for green collagen solvents to prepare collagen-based composite with well triple-helical structure for tissue engineering.


Habitualmente, os ácidos inorgânicos fracos têm sido usados para dispersar colágeno como solventes verdes para fabricar tipos de biomateriais o tempo todo. No entanto, é uma questão aberta quanto o processo de dissolução preserva ou altera a estrutura nativa do colágeno até agora. Aqui, examinamos o efeito de três solventes diferentes (HAc, HCl, H3PO4) nas estruturas secundárias de colágeno, com base em espectros de dicroísmo circular (CD) de colágeno de 185 a 260 nm em conjunto com programas CDNN. Descobrimos que o colágeno preservou quase completamente sua estrutura helicoidal tripla nos três ácidos inorgânicos a pH = 3,0 ou mais, o que demonstrou que foi a concentração de H+ livre nas três soluções acima cujo pH foi fixado em 3,0 que pode manter uma boa quantidade de carga superficial sobre as partículas coloidais de colágeno e destrói adequadamente a estrutura de três hélices, o que não só pode levar a um melhor comportamento de dispersão, mas também maximizar a preservação da integridade da estrutura de colágeno. Embora as frações de tipos de estruturas secundárias em colágeno fossem diferentes de todos os três solventes com base em dados CDNN, que deram resultados muito semelhantes entre si. Estes resultados foram testados pela primeira vez neste trabalho para estimar as estruturas secundárias para o colágeno nos diferentes ácidos inorgânicos comuns, o que fornece uma nova alternativa para solventes de colágeno verdes para preparar compósitos à base de colágeno com a estrutura helicoidal tripla para engenharia de tecidos.


Assuntos
Dicroísmo Circular , Colágeno Tipo I , Ácidos Inorgânicos , Solventes , Materiais Biocompatíveis
3.
J Magn Reson Imaging ; 45(6): 1684-1692, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27862557

RESUMO

PURPOSE: To establish normal reference values of left ventricular (LV) and right ventricular (RV) dimension, volume, mass, and ejection fraction in a Chinese population using cardiac magnetic resonance imaging (MRI). MATERIALS AND METHODS: A total of 120 (60 males; 60 females; 23-83 years) healthy Han Chinese subjects without cardiovascular disease or risk factors were recruited. They underwent comprehensive MRI examination at 3.0T. LV/RV morphology and function were evaluated by steady-state free-procession (SSFP) sequence. Parameters were analyzed according to a standard postprocessing protocol. RESULTS: Significant differences in LV size, mass, volume, and ejection fraction (EF) between sexes were noted (all P < 0.05). After indexing using body surface area (BSA), LV end-diastolic volume (EDV), and LV mass index were greater in males than in females (76.5 vs. 68.7 mL/m, P < 0.001; 52.9 vs. 45.1 g/m, P < 0.001; respectively). LVEF was lower in males than in females (64.6% vs. 67.1%, P = 0.007, respectively). RV volume was higher and RVEF lower in males compared with females (75.3 vs. 62.7 mL/m, P < 0.001; 59.9% vs. 62.6%, P = 0.001, respectively). Age was associated significantly with indices of LV and RV volume in females (left ventricular end-diastolic volume index: r = -0.41 P = 0.001; left ventricular end-systolic volume index: r = -0.37 P = 0.004; left ventricular end-diastolic volume index: r = -0.53 P < 0.001; right ventricular end-systolic volume index: r = -0.43 P < 0.001), but not in males (all P > 0.05). CONCLUSION: These data suggest that sex and age affect ventricular parameters in healthy Han Chinese subjects without cardiovascular disease or risk factors. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;45:1684-1692.


Assuntos
Envelhecimento/fisiologia , Testes de Função Cardíaca/normas , Ventrículos do Coração/anatomia & histologia , Ventrículos do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/normas , Volume Sistólico , Função Ventricular/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores Sexuais , Adulto Jovem
4.
Luminescence ; 31(7): 1384-1394, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26923950

RESUMO

In this study, the interaction between a novel ruthenium(II) arene complex with curcumin analogs and calf thymus DNA (ctDNA) was investigated systematically by viscosity measurement, the DNA melting approach, multispectroscopic techniques and electrochemical methods. The absorption spectra of the ctDNA-drug complex showed a slight red shift and a weak hypochromic effect. The relative viscosity and melting temperature of ctDNA increased on addition of the drug. The evidence obtained from fluorescence competitive experiments indicated that the binding mode of the drug with ctDNA was intercalative. Using acridine orange (AO) as a fluorescence probe, the drug statically quenched the fluorescence of the ctDNA-AO complex, and hydrogen bonding and van der Waals interactions played vital roles in the binding interaction between the drug and ctDNA. The influences of ionic strength, chemical denaturants and pH on the binding interaction were also investigated. Circular dichroism and Fourier transform infrared spectra suggested that this drug might bond with the G-C base pairs of ctDNA and the right-handed B-form helicity of ctDNA remained after drug binding. The intercalative binding between the drug and ctDNA was further investigated using electrochemical techniques. All these results suggested that the biological activity of ctDNA was affected by ruthenium(II) arene complex with curcumin analogs. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Curcumina/química , DNA/química , Rutênio/química , Animais , Benzeno/química , Sítios de Ligação , Bovinos , Dicroísmo Circular , Complexos de Coordenação/química , Eletroquímica , Viscosidade
5.
Biol Trace Elem Res ; 169(2): 189-203, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26170171

RESUMO

The interaction between two ruthenium(II) arene complexes of curcumin analogs and human serum albumin (HSA) was systematically investigated by multispectroscopic techniques. The fluorescence spectral results indicated that two complexes quenched the intrinsic fluorescence of HSA through static quenching mode. The quenching constants and the corresponding thermodynamic parameters at different temperatures were calculated. The binding interactions of two complexes with HSA resulted in the complex formation of complex-HSA, and the van der Waals interactions and hydrogen bond interactions played major roles in the complex stabilization. The distances between HSA and two complexes were obtained according to fluorescence resonance energy transfer theory. The site competitive replacement experiments illustrated that two complexes mainly bounded with HSA on site I. The results of synchronous fluorescence spectra, three-dimensional fluorescence spectra, FT-IR spectra, and circular dichroism spectra indicated that the secondary structure of HSA was changed at the present of two complexes. The results of mass spectrometry further validated the binding interaction and the binding number between two complexes and HSA.


Assuntos
Complexos de Coordenação/química , Curcumina/análogos & derivados , Hidrocarbonetos Aromáticos/química , Rutênio/química , Albumina Sérica/química , Dicroísmo Circular , Interações Medicamentosas , Humanos , Modelos Químicos , Estrutura Molecular , Ligação Proteica , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
6.
Eur J Drug Metab Pharmacokinet ; 41(4): 449-56, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25854676

RESUMO

The aim of this study was to investigate the role of P-glycoprotein (P-gp) in the intestinal absorption of triptolide. In this research, the bidirectional transport of triptolide across Caco-2 cells was studied in vitro. Moreover, the pharmacokinetic profiles of orally administered triptolide with and without pretreatment with verapamil were determined in rats. A markedly higher transport of triptolide across Caco-2 cells was observed in the basolateral-to-apical direction and was abrogated in the presence of the P-gp inhibitor, verapamil. The result indicated that P-gp might be involved in the absorption of triptolide. When the rats were pretreated with verapamil, the C max of triptolide increased from 423.01 ± 19.59 to 565.33 ± 20.27 ng/mL (33.6 %), and the AUC0-6 h increased by approximately 57 % when co-administered with verapamil. It was demonstrated that P-gp was involved in the transport of triptolide, which might exhibit a role in limiting its absorption and attenuating the toxicity of triptolide.


Assuntos
Diterpenos/farmacocinética , Fenantrenos/farmacocinética , Verapamil/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Linhagem Celular Tumoral , Compostos de Epóxi/farmacocinética , Feminino , Humanos , Absorção Intestinal/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
7.
Inorg Chem ; 52(21): 12440-9, 2013 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-24143913

RESUMO

A series of ketone-N(4)-substituted thiosemicarbazone (TSC) compounds (L1-L9) and their corresponding [(η(6)-p-cymene)Ru(II)(TSC)Cl](+/0) complexes (1-9) were synthesized and characterized by NMR, IR, elemental analysis, and HR-ESI-mass spectrometry. The molecular structures of L4, L9, 1-6, and 9 were determined by single-crystal X-ray diffraction analysis. The compounds were further evaluated for their in vitro antiproliferative activities against the SGC-7901 human gastric cancer, BEL-7404 human liver cancer, and HEK-293T noncancerous cell lines. Furthermore, the interactions of the compounds with DNA were followed by electrophoretic mobility spectrometry studies.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Rutênio/química , Tiossemicarbazonas/química , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Complexos de Coordenação , Cristalografia por Raios X , DNA/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Eletroforese em Gel de Ágar , Células HEK293/efeitos dos fármacos , Humanos , Cetonas/química , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Tiossemicarbazonas/síntese química
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(10): 2333-5, 2339, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-20965839

RESUMO

OBJECTIVE: To evaluate the effect of Wulongdan on the learning and memory abilities of rats with chronic cerebral ischemia and explore the mechanisms. METHODS: Male SD Rat models of chronic cerebral ischemia were established by permanent ligation of the bilateral carotid arteries. Three weeks after the operation, the rats were randomly divided into sham-operated group, chronic cerebral ischemia group (model group), high-dose drug group, low-dose drug group and Yinxingye group and received the corresponding treatments on a daily basis for 5 consecutive weeks. Morris water maze was used to assess the learning and memory abilities of the rats, and Western blotting was carried out for detecting the expressions of NR1 and NR2B in the hippocampus and cerebral cortex. RESULTS: Compared with the model group, the rats in high-dose drug, low-dose drug and Yinxingye groups showed significantly shorter time of finding platform in Morris water maze test (P<0.05 or 0.01). The rats in the model group showed significantly lowered expressions of NR1 and NR2B of the cortex and hippocampus than those in the sham-operated group (P<0.01). In comparison with the model group, the high-dose Wulongdan group and Yinxingye group both showed significantly increase expressions of NR1 and NR2B (P<0.01), but their expression levels still remained significantly lower than those in the sham-operated group (P<0.01). CONCLUSION: Wulongdan can enhance the learning and memory abilities of rats with chronic cerebral ischemia, the mechanisms of which may involve increased expressions of NR1 and NR2B in the hippocampus and cortex.


Assuntos
Isquemia Encefálica/psicologia , Medicamentos de Ervas Chinesas/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Animais , Isquemia Encefálica/tratamento farmacológico , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Fitoterapia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(12): 2421-4, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20034892

RESUMO

OBJECTIVE: To evaluate the effect of Wulongdan, a tradition Chinese medicinal preparation, on the learning and memory abilities of rats with chronic cerebral ischemia and explore the mechanisms. METHODS: Male rats with chronic cerebral ischemia induced by permanent ligation of the bilateral carotid arteries were randomized into sham-operated group, chronic cerebral ischemia (model) group, and high-, middle-, and low-dose Wulongdan groups and Yinxingye group. The corresponding treatments were administered in the rats 24 h after the operation once daily for 8 consecutive weeks. Morris water maze and step-through tests were performed after 7 weeks of drug administration. The brain tissues were then taken to observe the morphological changes in the hippocampal neurons with Nissl staining by transmission electron microscopy. RESULTS: Compared with the model group, the latency of finding the platform in Morris water maze test was significantly shortened (P<0.05 or 0.01), and that in step-through test significantly prolonged (P<0.05 or 0.01) in high-, middle-, and low-dose Wulongdan groups and Yinxingye group. In the model group, Nissl staining of the hippocampal CA1 region visualized obvious pathological changes in the neurons, showing a significant difference from the sham-operated and high-dose Wulongdan groups. CONCLUSION: Wulongdan can enhance the learning and memory abilities of rats with chronic cerebral ischemia possibly through a mechanism in relation to neuronal protection in the hippocampus CA1 region.


Assuntos
Isquemia Encefálica/fisiopatologia , Medicamentos de Ervas Chinesas/farmacologia , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Isquemia Encefálica/tratamento farmacológico , Doença Crônica , Medicamentos de Ervas Chinesas/uso terapêutico , Hipocampo/patologia , Masculino , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Fitoterapia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
10.
Zhong Yao Cai ; 28(7): 599-601, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16252731

RESUMO

OBJECTIVE: To optimize the best extracting procedure for Radix Panacis Quinquefolii. METHODS: (1) The optimum alcohol extracting procedure was selected with the content and extraction efficiency of ginsenoside Rg, Re, Rb, from Radix Panacis Quinquefolii by orthogonal test design and synthesizing multiple guidelines method. (2) The content of three ginsenoides Rg1, Re and Rb1 in Radix Panacis Quinquefolii was determined by gradient elution method in RP-HPLC. RESULTS: The optimum alcohol-extracting procedure was determined as 12 times of 70% alcohol refluxing and extracting 3 h for 2 times. CONCLUSIONS: The optimum extracting procedure can increase extraction efficiency of Radix Panacis Quinquefolii.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Ginsenosídeos/isolamento & purificação , Panax/química , Plantas Medicinais/química , Tecnologia Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Etanol , Ginsenosídeos/análise , Raízes de Plantas/química , Controle de Qualidade , Tempo
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