Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732136

RESUMO

In the context of sustainable agriculture and biomaterial development, understanding and enhancing plant secondary cell wall formation are crucial for improving crop fiber quality and biomass conversion efficiency. This is especially critical for economically important crops like upland cotton (Gossypium hirsutum L.), for which fiber quality and its processing properties are essential. Through comprehensive genome-wide screening and analysis of expression patterns, we identified a particularly high expression of an R2R3 MYB transcription factor, GhMYB52 Like, in the development of the secondary cell wall in cotton fiber cells. Utilizing gene-editing technology to generate a loss-of-function mutant to clarify the role of GhMYB52 Like, we revealed that GhMYB52 Like does not directly contribute to cellulose synthesis in cotton fibers but instead represses a subset of lignin biosynthesis genes, establishing it as a lignin biosynthesis inhibitor. Concurrently, a substantial decrease in the lint index, a critical measure of cotton yield, was noted in parallel with an elevation in lignin levels. This study not only deepens our understanding of the molecular mechanisms underlying cotton fiber development but also offers new perspectives for the molecular improvement of other economically important crops and the enhancement of biomass energy utilization.


Assuntos
Fibra de Algodão , Regulação da Expressão Gênica de Plantas , Gossypium , Lignina , Proteínas de Plantas , Lignina/biossíntese , Gossypium/genética , Gossypium/metabolismo , Gossypium/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Parede Celular/metabolismo , Parede Celular/genética , Celulose/biossíntese , Celulose/metabolismo , Vias Biossintéticas
2.
Mol Genet Genomics ; 293(5): 1139-1149, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29752547

RESUMO

Cotton fibers are the most important natural raw material used in textile industries world-wide. Fiber length, strength, and fineness are the three major traits which determine the quality and economic value of cotton. It is known that exogenous application of phosphatidylinositols (PtdIns), important structural phospholipids, can promote cotton fiber elongation. Here, we sought to increase the in planta production of PtdIns to improve fiber traits. Transgenic cotton plants were generated in which the expression of a cotton phosphatidylinositol synthase gene (i.e., GhPIS) was controlled by the fiber-specific SCFP promoter element, resulting in the specific up-regulation of GhPIS during cotton fiber development. We demonstrate that PtdIns content was significantly enhanced in transgenic cotton fibers and the elevated level of PtdIns stimulated the expression of genes involved in PtdIns phosphorylation as well as promoting lignin/lignin-like phenolic biosynthesis. Fiber length, strength and fineness were also improved in the transgenic plants as compared to the wild-type cotton, with no loss in overall fiber yield. Our data indicate that fiber-specific up-regulation of PtdIns synthesis is a promising strategy for cotton fiber quality improvement.


Assuntos
CDP-Diacilglicerol-Inositol 3-Fosfatidiltransferase/genética , Fibra de Algodão , Gossypium/genética , Plantas Geneticamente Modificadas/genética , Regulação da Expressão Gênica de Plantas , Gossypium/crescimento & desenvolvimento , Lignina/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
3.
Blood Cells Mol Dis ; 59: 16-24, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27282562

RESUMO

BACKGROUND: The multidrug resistance of leukemia cells is closely related to the microenvironment. The present leukemia microenvironment models focus on two-dimensional co-culture system in vitro which does not mimic the in vivo cell growth, while the 3D polystyrene (PS) scaffolds have the advantage. Stromal cell derived factor-1 may be involved in the shielding of endosteal niche from leukemia cells by binding to its receptor CXCR4, but the relationship between SDF-1/CXCR4 axis and leukemia cells is unclear. DESIGN AND METHODS: The experiments were built on the 3D PS scaffolds coated with osteoblasts. Stromal cells and MV4-11 cells were plated on the scaffolds. Then G-CSF, AMD3100 and cytarabine were added. Adhesive rate, SDF-1 level, migration state, apoptosis rate, and cell cycle of leukemia cells were observed after incubation at 24h and 48h. RESULTS: G-CSF decreased the level of SDF-1 and inhibited the expression of CXCR4 and promoted stationary phase leukemia cells to enter the mitotic phase and enhanced the killing effect of chemotherapeutic drugs. AMD3100 disrupted the interaction between tumors and matrix, mobilized the leukemia cells to keep away from the protective microenvironment and strengthened the cytotoxic effect of Ara-C. The combination of G-CSF and AMD3100 had stronger effects on killing the leukemia cells induced by Ara-C. CONCLUSION: It demonstrates that AMD3100 and G-CSF may inhibit adhesion and migration abilities of leukemia cells with the bone marrow niche. Both of them inhibit the role of SDF-1/CXCR4 directly or indirectly. Thus inhibiting SDF-1/CXCR4 axis may be helpful to the treatment of refractory AML.


Assuntos
Materiais Biomiméticos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Compostos Heterocíclicos/farmacologia , Leucemia/patologia , Receptor Cross-Talk/efeitos dos fármacos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzilaminas , Adesão Celular , Movimento Celular , Células Cultivadas , Quimiocina CXCL12/metabolismo , Ciclamos , Citarabina/farmacologia , Humanos , Leucemia Mieloide Aguda/patologia , Poliestirenos , Receptores CXCR4/metabolismo , Células Estromais/citologia
4.
Plant Cell ; 25(11): 4421-38, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24220634

RESUMO

LIN-11, Isl1 and MEC-3 (LIM)-domain proteins play pivotal roles in a variety of cellular processes in animals, but plant LIM functions remain largely unexplored. Here, we demonstrate dual roles of the WLIM1a gene in fiber development in upland cotton (Gossypium hirsutum). WLIM1a is preferentially expressed during the elongation and secondary wall synthesis stages in developing fibers. Overexpression of WLIM1a in cotton led to significant changes in fiber length and secondary wall structure. Compared with the wild type, fibers of WLIM1a-overexpressing plants grew longer and formed a thinner and more compact secondary cell wall, which contributed to improved fiber strength and fineness. Functional studies demonstrated that (1) WLIM1a acts as an actin bundler to facilitate elongation of fiber cells and (2) WLIM1a also functions as a transcription factor to activate expression of Phe ammonia lyase-box genes involved in phenylpropanoid biosynthesis to build up the secondary cell wall. WLIM1a localizes in the cytosol and nucleus and moves into the nucleus in response to hydrogen peroxide. Taken together, these results demonstrate that WLIM1a has dual roles in cotton fiber development, elongation, and secondary wall formation. Moreover, our study shows that lignin/lignin-like phenolics may substantially affect cotton fiber quality; this finding may guide cotton breeding for improved fiber traits.


Assuntos
Parede Celular/metabolismo , Fibra de Algodão , Gossypium/citologia , Gossypium/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Actinas/metabolismo , Núcleo Celular/metabolismo , Parede Celular/genética , Parede Celular/ultraestrutura , Clonagem Molecular , Citoplasma/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/efeitos dos fármacos , Gossypium/genética , Peróxido de Hidrogênio/farmacologia , Lignina/metabolismo , Filogenia , Células Vegetais/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Transporte Proteico/efeitos dos fármacos
5.
Plant Sci ; 346: 112161, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38879177

RESUMO

Paper mulberry (Broussonetia papyrifera) is a fast-growing tree known for its tolerance to diverse biotic and abiotic stresses. To explore genes combating Verticillium wilt, a devasting and formidable disease damage to cotton and many economically significant crops, we purified an antifungal protein, named BpAFP, from the latex of paper mulberry. Based on peptide fingerprint, we cloned the full cDNA sequence of BpAFP and revealed that BpAFP belongs to Class I chitinases, sharing 74 % identity with B. papyrifera leaf chitinase, PMAPII. We further introduced BpAFP into Arabidopsis, tobacco, and cotton. Transgenic plants exhibited significant resistance to Verticillium wilt. Importantly, BpAFP also demonstrated insecticidal activity against herbivorous pests, Plutella xylostella, and Prodenia litura, when feeding the larvae with transgenic leaves. Our finding unveils a dual role of BpAFP in conferring resistance to both plant diseases and lepidopterous pests.


Assuntos
Quitinases , Látex , Mariposas , Doenças das Plantas , Plantas Geneticamente Modificadas , Verticillium , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Quitinases/metabolismo , Quitinases/genética , Animais , Mariposas/fisiologia , Verticillium/fisiologia , Látex/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resistência à Doença/genética , Filogenia , Arabidopsis/genética , Arabidopsis/microbiologia
6.
Shanghai Kou Qiang Yi Xue ; 33(2): 141-147, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-39005089

RESUMO

PURPOSE: To study the stability of physicochemical properties and sterilizing effect about two commercially available hypochlorous acid (HClO) products under simulated clinical conditions, and to evaluate the compatibility of HClO on soft and hard tissues and cells in oral cavity. METHODS: Samples of HClO solution with different production processes were prepared, to detect the changes of physicochemical indexes of each sample over time under simulated clinical conditions (shielded from light at 20-25 ℃, open the cover for 5 minutes every day), including free available chlorine, oxidation-reduction potential and pH. Through suspension quantitative germicidal test, the antibiosis-concentration curve of HClO solution was made, so as to calibrate the change of antibacterial ability of disinfectant with the decrease of available chlorine content during storage. Pulp, tongue and dentine were immersed in PBS, 100 ppm HClO, 200 ppm HClO and 3% NaClO. The influence on soft and hard tissues was evaluated by weighing method and microhardness test. The toxic effects of HClO, NaClO and their 10-fold diluent on human gingival fibroblasts were determined by CCK-8 cytotoxicity assay. GraphPad PRIS 8.0 software was used to analyze the data. RESULTS: Under simulated conditions, the free available chlorine (FAC) of HClO solution decayed with time, and the attenuation degree was less than 20 ppm within 1 month. The bactericidal effect of each HClO sample was still higher than 5log after concentration decay. There was no obvious dissolution and destruction to soft and hard tissues for HClO(P>0.05). The cell viability of HClO to human gingival fibroblast cells (HGFC) was greater than 80%, which was much higher than 3% NaClO (P<0.001). CONCLUSIONS: The bactericidal effect and stability of HClO solution can meet clinical needs, which has low cytotoxicity and good histocompatibility. It is expected to become a safe and efficient disinfection product in the field of living pulp preservation and dental pulp regeneration.


Assuntos
Fibroblastos , Ácido Hipocloroso , Boca , Ácido Hipocloroso/química , Humanos , Boca/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Gengiva/citologia , Gengiva/efeitos dos fármacos , Irritantes , Desinfetantes/farmacologia , Desinfetantes/química , Antibacterianos/farmacologia , Antibacterianos/química
7.
Am J Rhinol Allergy ; 33(2): 184-193, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30704266

RESUMO

BACKGROUND: Perennial allergic rhinitis (PAR) often coexists in asthmatic patients. Intranasal cellulose powder (ICP) was reportedly effective in ameliorating PAR. OBJECTIVE: We investigated whether ICP is equally effective compared with intranasal corticosteroids in improving asthma control as well as nasal symptoms among children with PAR and allergic asthma (AA). METHODS: Between July 2015 and September 2016, we did a single-center, randomized, placebo-controlled trial. Asthmatic children aged 6 to 11 years with mild-to-moderate PAR were randomly assigned to formoterol/budesonide inhalation (4·5 µg/80 µg, twice daily) plus intranasal budesonide 64 µg twice daily (group A), ICP 250 µg thrice daily (group B), or intranasal placebo 250 µg thrice daily (group C) for 8 weeks. The primary outcome was change in asthma control test for children (C-ACT) score from baseline to week 8 posttreatment. Changes in spirometry, peak expiratory flow (PEF), fractional exhaled nitric oxide (FeNO), and visual analog scale (VAS) for nasal and ocular symptoms were detected as secondary outcomes. RESULTS: We included 121 patients (38 in group A, 41 in group B, and 42 in group C) in full-analysis set. C-ACT score was markedly higher at week 8 compared with baseline (mean difference: 5.11, 6.05, and 4.85 points in groups A, B, and C, respectively; P < .05). There were interactions between baseline and treatment in C-ACT scores ( P < .05). Group B demonstrated greater improvement in C-ACT score than group C among children with baseline C-ACT score of 6 to 18. 95% confidence intervals of group A at baseline overlapped with those of groups B and C. The treatment achieved reduced VAS symptoms in groups A and B but not in group C. Incidence of adverse events was comparable. No serious adverse event was reported. CONCLUSIONS: ICP could be recommended for children with PAR and AA who have poorer asthma control.


Assuntos
Asma/prevenção & controle , Celulose/administração & dosagem , Rinite Alérgica Perene/prevenção & controle , Administração por Inalação , Administração Intranasal , Corticosteroides/administração & dosagem , Criança , Método Duplo-Cego , Humanos , Testes de Função Respiratória , Resultado do Tratamento
8.
PLoS One ; 9(5): e96537, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24816840

RESUMO

Bioactive gibberellins (GAs) comprise an important class of natural plant growth regulators and play essential roles in cotton fiber development. To date, the molecular base of GAs' functions in fiber development is largely unclear. To address this question, the endogenous bioactive GA levels in cotton developing fibers were elevated by specifically up-regulating GA 20-oxidase and suppressing GA 2-oxidase via transgenic methods. Higher GA levels in transgenic cotton fibers significantly increased micronaire values, 1000-fiber weight, cell wall thickness and cellulose contents of mature fibers. Quantitative RT-PCR and biochemical analysis revealed that the transcription of sucrose synthase gene GhSusA1 and sucrose synthase activities were significantly enhanced in GA overproducing transgenic fibers, compared to the wild-type cotton. In addition, exogenous application of bioactive GA could promote GhSusA1 expression in cultured fibers, as well as in cotton hypocotyls. Our results suggested that bioactive GAs promoted secondary cell wall deposition in cotton fibers by enhancing sucrose synthase expression.


Assuntos
Parede Celular/enzimologia , Fibra de Algodão/normas , Giberelinas/metabolismo , Glucosiltransferases/metabolismo , Gossypium/enzimologia , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Parede Celular/genética , Celulose/biossíntese , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Giberelinas/farmacologia , Glucosiltransferases/classificação , Glucosiltransferases/genética , Gossypium/genética , Hipocótilo/enzimologia , Hipocótilo/genética , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Dados de Sequência Molecular , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Interferência de RNA , Homologia de Sequência de Aminoácidos
9.
J Biomed Mater Res A ; 100(2): 441-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22105865

RESUMO

The biodegradable polylactide/poly(ethylene glycol) (PLA/PEG) hybrid membranes were fabricated via electrospinning of PLA/PEG solution. Their structures and properties were investigated by scanning electron microscopy, differential scanning calorimetry, and water contact angle. In vitro hydrolytic degradation showed that PEG content influenced the degradation rate of the PLA/PEG hybrid mats. The mechanical property was measured by tensile test and the result revealed that the addition of PEG had an obvious plasticization on PLA matrix. In-vitro biocompatibility was investigated by culturing cell on the scaffolds and MTT assay. The results indicated that the cell could attach and proliferate on the membranes, so confirmed that the PLA/PEG hybrid membrane had good biocompatibility, and it could be a promising biomaterial for tissue engineering applications.


Assuntos
Polietilenoglicóis/farmacologia , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Varredura Diferencial de Calorimetria , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Hidrólise , Camundongos , Células NIH 3T3 , Estresse Mecânico , Temperatura , Resistência à Tração/efeitos dos fármacos , Água/química
10.
J Biomed Mater Res A ; 100(1): 171-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22009709

RESUMO

In orthopedic tissue engineering, the extensively applied acellular bone matrix (ABM) can seldom be prefabricated just right to mold the cavity of the diverse defects, might induce severe inflammation on account of the migration of small granules and usually bring the patients great pain in the treatment. In this study, a new injectable thermosensitive ABM/PECE composite with good biocompatibility was designed and prepared by adding the ABM granules into the triblock copolymer poly(ethylene eglycol)-poly(ε-caprolactone)-poly(ethylene eglycol) (PEG-PCL-PEG, PECE). The PECE was synthesized by ring-opening copolymerization and characterized by ¹H NMR. The ABM was prepared by acellular treatment of natural bone and ground to fine granules. The obtained ABM/PECE composite showed the most important absorption bands of ABM and PECE copolymer in FT-IR spectroscopy and underwent sol-gel phage transition from solution to nonflowing hydrogel at 37°C. SEM results indicated that the ABM/PECE composite with different ABM contents all presented similar porous 3D structure. ABM/PECE composite presented mild cytotoxicity to rat MSCs in vitro and good biocompatibility in the BALB/c mice subcutis up to 4 weeks. In conclusion, all the results confirmed that the injectable thermosensitive ABM/PECE composite was a promising candidate for orthopedic tissue engineering in a minimally-invasive way.


Assuntos
Materiais Biocompatíveis/farmacologia , Matriz Óssea/metabolismo , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Poliésteres/síntese química , Poliésteres/farmacologia , Polietilenoglicóis/síntese química , Polietilenoglicóis/farmacologia , Temperatura , Animais , Matriz Óssea/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Humanos , Injeções , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura , Transição de Fase/efeitos dos fármacos , Poliésteres/química , Poliésteres/toxicidade , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Ratos , Ratos Sprague-Dawley , Reologia/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/patologia
11.
Orthop Surg ; 3(4): 265-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22021144

RESUMO

OBJECTIVE: To compare the influence of different methods of adding vancomycin on the strength of bone cement used for fixing rabbits' femoral prostheses. METHODS: Eighteen New Zealand white rabbits (36 femora) were allocated to three groups of six rabbits (12 femora) each: a control group, an experimental group 1 and experimental group 2. The bone cement used in the control group was mixed manually without vancomycin; in experimental group 1 it was mixed manually with 5% (2 g/40 g) vancomycin; and in experimental group 2 it was mixed in a vacuum with 5% (2 g/40 g) vancomycin. The cement combinations were then used to fill the marrow cavity of rabbit femurs to fix prostheses. An electronic universal testing machine (EUTM) was used to test the pullout force of the prostheses with bone cement 48 hours later. Student's paired t-test was used for statistical analysis. RESULTS: It was found that the maximum load of pullout force was 559.3 ± 82.3 N in the control group; 523.6 ± 86.5 N in experimental group 1; and 645.1 ± 105.9 N in experimental group 2. Statistical analysis showed there was no significant difference between the control group and experimental group 1 (P > 0.05). However, there were significant differences between the control group and experimental group 2 (P < 0.05); and between experimental group 1 and experimental group 2 (P < 0.05). CONCLUSION: When bone cement and vancomycin were mixed manually in a low concentration (<5%) vancomycin had no influence on the strength of the bone cement. However, bone cement and vancomycin mixed at the same concentrations in a vacuum did have a statistically significant effect on the strength of the bone cement.


Assuntos
Cimentos Ósseos/uso terapêutico , Fêmur/cirurgia , Próteses e Implantes , Vancomicina/farmacologia , Animais , Fenômenos Biomecânicos , Modelos Animais de Doenças , Masculino , Teste de Materiais , Desenho de Prótese , Coelhos , Distribuição Aleatória , Valores de Referência , Sensibilidade e Especificidade , Estresse Mecânico , Resistência à Tração
12.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 29(3): 264-7, 271, 2011 Jun.
Artigo em Zh | MEDLINE | ID: mdl-21776851

RESUMO

OBJECTIVE: The morphological characteristics of posterior tooth in the Beagle dog were investigated in order to provide reference to mini-screw implant (MSI) implantation in the root furcation site. METHODS: Seventy posterior teeth of five Beagle dogs were collected and measured as follows: First, the greatest mesio-distal diameter AB of the crown was measured, which was perpendicular to the tooth long axis. Second, mesial cusp of maxillary posterior tooth or central cusp of mandibular was marked as the piont C, and CD which was equal and perpendicular to AB was drawn. The piont D was planned to be the reference point for MSI implantation. Finally, Dm, Dd and Df were measured, which were the distance from the point D to the mesial and distal root surface and root furcation. RESULTS: The difference between the left and right sides teeth with the same name had no statistical significant (P > 0.05). The measurement results of all indices assumed a Gaussian distribution. The mean Dd was basically equal to Dm. All the average Df were more than 4 mm. CONCLUSION: The point D could be used as a reference point for MSI implantation in the root furcation site of posterior tooth in the Beagle dog. The data of this study can provide certain reference for MSI implantation in the study of the biomechanics of anchorage stability, and provide certain reference for MSI implantation in the study of root repair after injury.


Assuntos
Parafusos Ósseos , Dente , Animais , Cães , Mandíbula , Maxila , Técnicas de Movimentação Dentária , Raiz Dentária
13.
J Biomed Nanotechnol ; 6(4): 325-32, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21323105

RESUMO

With the aim to enhance dissolution rate and oral bioavailability of quercetin, a poorly water-soluble drug, quercetin loaded nanosuspension (QT-NS) was fabricated by a tandem of nano-precipitation (NP) and high pressure homogenization (HPH) method. The formulation of nanosuspension was optimized by screening different stabilizers. Characterization of the original QT powder and QT-NS was carried out by transmission electron microscopy and scanning electron microscopy, X-ray diffraction (XRD) and dissolution tests. QT-NS presented a sphere-like shape under transmission electron microscopy with an average diameter of 393.5 nm and the zeta potential of -35.75 mV. XRD study suggested that QT was maintained in the state of crystalline during the fabrication process. The solubility of QT in nanosuspension was about 70-fold that of crude QT, and the dissolution of QT from QT-NS was increased as compared to that of the original QT powder. In plasma, QT-NS exhibited a significant reduction of clearance rate (2 +/- 0.1 mL/min vs. 15 +/- 4 mL/min) and increase of AUC(0-infinity), (53995 +/- 4126 microg/mL x min versus 3470 +/- 110.1 microg/mL x min) compared with the control suspension. Our results showed that the developed nanosuspension formulation had a great potential as a possible formulation of the poorly water-soluble QT to enhance the bioavailability.


Assuntos
Quercetina/química , Administração Oral , Animais , Disponibilidade Biológica , Química Farmacêutica/métodos , Masculino , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Nanotecnologia , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Polietilenoglicóis/química , Propilenoglicóis/química , Quercetina/administração & dosagem , Quercetina/farmacocinética , Ratos , Ratos Wistar , Solubilidade , Suspensões
14.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 27(2): 157-9, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19472878

RESUMO

OBJECTIVE: To compare the adaptation of porcelain fused-to-metal (PFM) restorations made from Ni-Cr alloy, precious alloy and galvanized forming copings after cementation and to provide a theory guidance for their application. METHODS: Three kinds of crowns (Ni-Cr alloy, precious alloy and galvanized forming) were manufactured and cleaned by ultrasonic vibrate with alcoholic solution for 5 minutes, and cemented on their dies as their order. All the crowns were cemented by polycarboxylate zinc-cement and maintained 10 minutes. After coated in the center of methyl acrylic resins, all the samples were cut vertically along buccolingual direction. The cement thickness of PFM was measured by scanning electron microscope and the data were analyzed by multivariate ANOVA. RESULTS: No significant difference was found between the cement thickness of precious alloy crown and galvanized forming crown (P>0.05), while both of these two kinds of crown had significant differences in cement thickness with Ni-Cr crown (P<0.05). CONCLUSION: The adaptation of precious alloy crown and galvanized forming crown are superior to Ni-Cr crown.


Assuntos
Coroas , Porcelana Dentária , Cimentação , Cimentos Dentários , Cimentos de Ionômeros de Vidro , Metais
15.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 23(2): 133-5, 2005 Apr.
Artigo em Zh | MEDLINE | ID: mdl-15952626

RESUMO

OBJECTIVE: To compare the color differences of different metal bases and different opaque thickness, and evaluate the best thickness of opaque on different metal bases. METHODS: Precious metal, gold sediment and Ni-Cr plates were prepared as bases, then opaque samples of 0.05, 0.1, 0.2, 0.3, 0.4 and 0.5 mm thickness were fabricated on such plates. Minolta chromatics meter CR-321 was used to examine the color properties of these samples, and deltaE was calculated to evaluate the color difference of the specimens. RESULTS: For the restoration based on Ni-Cr and precious alloys, the color of restorations was not affected by the color of metal bases as the thickness of opaque reached 0.3 mm, and the chromatic value deltaE < 1.5 NBS. For the restoration based on gold sediment, the color of restoration was not affected by the color of metal as the thickness of opaque reached 0.1 mm, and the chromatic value deltaE < 1.5 NBS. CONCLUSION: Different opaque thickness was necessary to obtain ideal color appearance in clinic. As the opaque thickness increased, the color of restoration based on Ni-Cr and noble metal increased but the color of restoration based on gold sediment decreased.


Assuntos
Cor , Porcelana Dentária , Ligas Metalo-Cerâmicas , Ligas Dentárias , Ouro
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA