Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 80
Filtrar
1.
Chem Rec ; 24(1): e202300302, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38010947

RESUMO

As supercapacitor (SC) technology continues to evolve, there is a growing need for electrode materials with high energy/power densities and cycling stability. However, research and development of electrode materials with such characteristics is essential for commercialization the SC. To meet this demand, the development of superior electrode materials has become an increasingly critical step. The electrochemical performance of SCs is greatly influenced by various factors such as the reaction mechanism, crystal structure, and kinetics of electron/ion transfer in the electrodes, which have been challenging to address using previously investigated electrode materials like carbon and metal oxides/sulfides. Recently, tellurium and telluride-based materials have garnered increasing interest in energy storage technology owing to their high electronic conductivity, favorable crystal structure, and excellent volumetric capacity. This review provides a comprehensive understanding of the fundamental properties and energy storage performance of tellurium- and Te-based materials by introducing their physicochemical properties. First, we elaborate on the significance of tellurides. Next, the charge storage mechanism of functional telluride materials and important synthesis strategies are summarized. Then, research advancements in metal and carbon-based telluride materials, as well as the effectiveness of tellurides for SCs, were analyzed by emphasizing their essential properties and extensive advantages. Finally, the remaining challenges and prospects for improving the telluride-based supercapacitive performance are outlined.

2.
BMC Cancer ; 22(1): 916, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36002810

RESUMO

BACKGROUND: Extralevator abdominoperineal excision (ELAPE) has been recommended for treating low rectal cancer due to its potential advantages in improving surgical safety and oncologic outcomes as compared to conventional abdominoperineal excision (APE). In ELAPE, however, whether the benefits of intraoperative position change to a prone jackknife position outweighs the associated risks remains controversial. This study is to introduce a modified position change in laparoscopic ELAPE and evaluate its feasibility, safety and the long-term therapeutic outcomes. METHODS: Medical records of 56 consecutive patients with low rectal cancer underwent laparoscopic ELAPE from November 2013 to September 2016 were retrospectively studied. In the operation, a perineal dissection in prone jackknife position was firstly performed and the laparoscopic procedure was then conducted in supine position. Patient characteristics, intraoperative and postoperative outcomes, pathologic and 5-year oncologic outcomes were analyzed. RESULTS: The mean operation time was 213.5 ± 29.4 min and the mean intraoperative blood loss was 152.7 ± 125.2 ml. All the tumors were totally resected, without intraoperative perforation, conversion to open surgery, postoperative 30-day death, and perioperative complications. All the patients achieved pelvic peritoneum reconstruction without the usage of biological mesh. During the follow-up period, perineal hernia was observed in 1 patient, impaired sexual function in 1 patient, and parastomal hernias in 3 patients. The local recurrence rate was 1.9% and distant metastasis was noted in 12 patients. The 5-year overall survival rate was 76.4% and the 5-year disease-free survival rate was 70.9%. CONCLUSIONS: Laparoscopic ELAPE with modified position change is a simplified, safe and feasible procedure with favorable outcomes. The pelvic peritoneum can be directly closed by the laparoscopic approach without the application of biological mesh.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Laparoscopia , Protectomia , Neoplasias Retais , Abdome/patologia , Abdome/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Períneo/cirurgia , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
3.
Int J Mol Sci ; 24(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36614159

RESUMO

Yarrowia lipolytica is progressively being employed as a workhouse for recombinant protein expression. Here, we expanded the molecular toolbox by engineering the enolase promoter (pENO) and developed a new self-excisable vector, and based on this, a combined strategy was employed to enhance the expression of Thermomyces lanuginosus lipase (TLL) in Y. lipolytica. The strength of 11 truncated enolase promoters of different length was first identified using eGFP as a reporter. Seven of the truncated promoters were selected to examine their ability for driving TLL expression. Then, a series of enolase promoters with higher activities were developed by upstream fusing of different copies of UAS1B, and the recombinant strain Po1f/hp16e100-tll harboring the optimal promoter hp16e100 obtained a TLL activity of 447 U/mL. Additionally, a new self-excisable vector was developed based on a Cre/loxP recombination system, which achieved efficient markerless integration in Y. lipolytica. Subsequently, strains harboring one to four copies of the tll gene were constructed using this tool, with the three-copy strain Po1f/3tll showing the highest activity of 579 U/mL. The activity of Po1f/3tll was then increased to 720 U/mL by optimizing the shaking flask fermentation parameters. Moreover, the folding-related proteins Hac1, Pdi, and Kar2 were employed to further enhance TLL expression, and the TLL activity of the optimal recombinant strain Po1f/3tll-hac1-pdi-kar2 reached 1197 U/mL. By using this combined strategy, TLL activity was enhanced by approximately 39.9-fold compared to the initial strain. Thus, the new vector and the combined strategy could be a useful tool to engineer Y. lipolytica for high-level expression of heterologous protein.


Assuntos
Eurotiales , Yarrowia , Eurotiales/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Regiões Promotoras Genéticas
4.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430193

RESUMO

In nature, DNA is ubiquitous, existing not only inside but also outside of the cells of organisms. Intracellular DNA (iDNA) plays an essential role in different stages of biological growth, and it is defined as the carrier of genetic information. In addition, extracellular DNA (eDNA) is not enclosed in living cells, accounting for a large proportion of total DNA in the environment. Both the lysis-dependent and lysis-independent pathways are involved in eDNA release, and the released DNA has diverse environmental functions. This review provides an insight into the origin as well as the multiple ecological functions of eDNA. Furthermore, the main research advancements of eDNA in the various ecological environments and the various model microorganisms are summarized. Furthermore, the major methods for eDNA extraction and quantification are evaluated.


Assuntos
DNA , DNA Bacteriano/genética , DNA/genética
5.
Korean J Physiol Pharmacol ; 26(3): 145-155, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35477542

RESUMO

Multidrug resistance of tumors has been a severe obstacle to the success of cancer chemotherapy. The study wants to investigate the reversal effects of imperatorin (IMP) on doxorubicin (DOX) resistance in K562/DOX leukemia cells, A2780/Taxol cells and in NOD/SCID mice, to explore the possible molecular mechanisms. K562/DOX and A2780/Taxol cells were treated with various concentrations of DOX and Taol with or without different concentrations of IMP, respectively. K562/DOX xenograft model was used to assess anti-tumor effect of IMP combined with DOX. MTT assay, Rhodamine 123 efflux assay, RT-PCR, and Western blot analysis were determined in vivo and in vitro. Results showed that IMP significantly enhanced the cytotoxicity of DOX and Taxol toward corresponding resistance cells. In vivo results illustrated both the tumor volume and tumor weight were significantly decreased after 2-week treatment with IMP combined with DOX compared to the DOX alone group. Western blotting and RT-PCR analyses indicated that IMP downregulated the expression of P-gp in K562/DOX xenograft tumors in NOD/SCID mice. We also evaluated glycolysis and glutamine metabolism in K562/DOX cells by measuring glucose consumption and lactate production. The results revealed that IMP could significantly reduce the glucose consumption and lactate production of K562/DOX cells. Furthermore, IMP could also remarkably repress the glutamine consumption, α-KG and ATP production of K562/DOX cells. Thus, IMP may sensitize K562/DOX cells to DOX and enhance the anti-tumor effect of DOX in K562/DOX xenograft tumors in NOD/SCID mice. IMP may be an adjuvant therapy to mitigate the multidrug resistance in leukemia chemotherapy.

6.
Zhongguo Zhong Yao Za Zhi ; 47(1): 103-110, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-35178916

RESUMO

The present study explored the effect of co-amorphous technology in improving the dissolution rate and stability of silybin based on the puerarin-silybin co-amorphous system prepared by the spray-drying method. Solid-state characterization was carried out by powder X-ray diffraction(PXRD), polarizing microscopy(PLM), Fourier transform infrared spectroscopy(FT-IR), differential scanning calorimetry(DSC), etc. Saturated powder dissolution, intrinsic dissolution rate, moisture absorption, and stability were further investigated. The results showed that puerarin and silybin formed a co-amorphous system at a single glass transition temperature which was higher than that of any crude drug. The intrinsic dissolution rate and supersaturated powder dissolution of silybin in the co-amorphous system were higher than those of the crude drug and amorphous system. The co-amorphous system kept stable for as long as three months under the condition of 40 ℃, 75% relative humidity, which was longer than that of the single amorphous silybin. Therefore, the co-amorphous technology could significantly improve the dissolution and stability of silybin.


Assuntos
Dessecação , Tecnologia , Varredura Diferencial de Calorimetria , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Silibina , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
7.
Blood ; 133(23): 2518-2528, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-30971389

RESUMO

The microRNA (miRNA) locus miR-144/451 is abundantly expressed in erythrocyte precursors, facilitating their terminal maturation and protecting against oxidant stress. However, the full repertoire of erythroid miR-144/451 target messenger RNAs (mRNAs) and associated cellular pathways is unknown. In general, the numbers of mRNAs predicted to be targeted by an miRNA vary greatly from hundreds to thousands, and are dependent on experimental approaches. To comprehensively and accurately identify erythroid miR-144/451 target mRNAs, we compared gene knockout and wild-type fetal liver erythroblasts by RNA sequencing, quantitative proteomics, and RNA immunoprecipitation of Argonaute (Ago), a component of the RNA-induced silencing complex that binds miRNAs complexed to their target mRNAs. Argonaute bound ∼1400 erythroblast mRNAs in a miR-144/451-dependent manner, accounting for one-third of all Ago-bound mRNAs. However, only ∼100 mRNAs were stabilized after miR-144/451 loss. Thus, miR-144 and miR-451 deregulate <10% of mRNAs that they bind, a characteristic that likely applies generally to other miRNAs. Using stringent selection criteria, we identified 53 novel miR-144/451 target mRNAs. One of these, Cox10, facilitates the assembly of mitochondrial electron transport complex IV. Loss of miR-144/451 caused increased Cox10 mRNA and protein, accumulation of complex IV, and increased mitochondrial membrane potential with no change in mitochondrial mass. Thus, miR-144/451 represses mitochondrial respiration during erythropoiesis by inhibiting the production of Cox10.


Assuntos
Alquil e Aril Transferases/biossíntese , Eritropoese/genética , Regulação da Expressão Gênica/genética , Proteínas de Membrana/biossíntese , MicroRNAs/genética , Alquil e Aril Transferases/genética , Animais , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout
8.
Molecules ; 26(2)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33435543

RESUMO

Perovskite-type lithium ionic conductors were explored in the (LixLa1-x/3)ScO3 system following their syntheses via a high-pressure solid-state reaction. Phase identification indicated that a solid solution with a perovskite-type structure was formed in the range 0 ≤ x < 0.6. When x = 0.45, (Li0.45La0.85)ScO3 exhibited the highest ionic conductivity and a low activation energy. Increasing the loading of lithium as an ionic diffusion carrier expanded the unit cell volume and contributed to the higher ionic conductivity and lower activation energy. Cations with higher oxidation numbers were introduced into the A/B sites to improve the ionic conductivity. Ce4+ and Zr4+ or Nb5+ dopants partially substituted the A-site (La/Li) and B-site Sc, respectively. Although B-site doping produced a lower ionic conductivity, A-site Ce4+ doping improved the conductive properties. A perovskite-type single phase was obtained for (Li0.45La0.78Ce0.05)ScO3 upon Ce4+ doping, providing a higher ionic conductivity than (Li0.45La0.85)ScO3. Compositional analysis and crystal-structure refinement of (Li0.45La0.85)ScO3 and (Li0.45La0.78Ce0.05)ScO3 revealed increased lithium contents and expansion of the unit cell upon Ce4+ co-doping. The highest ionic conductivity of 1.1 × 10-3 S cm-1 at 623 K was confirmed for (Li0.4Ce0.15La0.67)ScO3, which is more than one order of magnitude higher than that of the (LixLa1-x/3)ScO3 system.


Assuntos
Compostos de Cálcio/química , Eletrodos , Eletrônica/instrumentação , Lantânio/química , Lítio/química , Óxidos/química , Escândio/química , Titânio/química , Condutividade Elétrica
9.
Haematologica ; 103(3): 406-416, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29269522

RESUMO

The microRNAs miR-144 and -451 are encoded by a bicistronic gene that is strongly induced during red blood cell formation (erythropoiesis). Ablation of the miR-144/451 gene in mice causes mild anemia under baseline conditions. Here we show that miR-144/451-/- erythroblasts exhibit increased apoptosis during recovery from acute anemia. Mechanistically, miR-144/451 depletion increases the expression of the miR-451 target mRNA Cab39, which encodes a co-factor for the serine-threonine kinase LKB1. During erythropoietic stress, miR-144/451-/- erythroblasts exhibit abnormally increased Cab39 protein, which activates LKB1 and its downstream AMPK/mTOR effector pathway. Suppression of this pathway via drugs or shRNAs enhances survival of the mutant erythroblasts. Thus, miR-144/451 facilitates recovery from acute anemia by repressing Cab39/AMPK/mTOR. Our findings suggest that miR-144/451 is a key protector of erythroblasts during pathological states associated with dramatically increased erythropoietic demand, including acute blood loss and hemolytic anemia.


Assuntos
Anemia/sangue , Células Eritroides/citologia , MicroRNAs/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Doença Aguda , Animais , Proteínas de Ligação ao Cálcio/genética , Sobrevivência Celular , Eritropoese , Redes e Vias Metabólicas , Camundongos , RNA Mensageiro , Serina-Treonina Quinases TOR/metabolismo
10.
Genes Dev ; 24(15): 1620-33, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20679398

RESUMO

The bicistronic microRNA (miRNA) locus miR-144/451 is highly expressed during erythrocyte development, although its physiological roles are poorly understood. We show that miR-144/451 ablation in mice causes mild erythrocyte instability and increased susceptibility to damage after exposure to oxidant drugs. This phenotype is deeply conserved, as miR-451 depletion synergizes with oxidant stress to cause profound anemia in zebrafish embryos. At least some protective activities of miR-451 stem from its ability to directly suppress production of 14-3-3zeta, a phospho-serine/threonine-binding protein that inhibits nuclear accumulation of transcription factor FoxO3, a positive regulator of erythroid anti-oxidant genes. Thus, in miR-144/451(-/-) erythroblasts, 14-3-3zeta accumulates, causing partial relocalization of FoxO3 from nucleus to cytoplasm with dampening of its transcriptional program, including anti-oxidant-encoding genes Cat and Gpx1. Supporting this mechanism, overexpression of 14-3-3zeta in erythroid cells and fibroblasts inhibits nuclear localization and activity of FoxO3. Moreover, shRNA suppression of 14-3-3zeta protects miR-144/451(-/-) erythrocytes against peroxide-induced destruction, and restores catalase activity. Our findings define a novel miRNA-regulated pathway that protects erythrocytes against oxidant stress, and, more generally, illustrate how a miRNA can influence gene expression by altering the activity of a key transcription factor.


Assuntos
Proteínas 14-3-3/metabolismo , Células Eritroides/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/metabolismo , Estresse Oxidativo , Proteínas 14-3-3/genética , Transporte Ativo do Núcleo Celular , Animais , Sequência de Bases , Catalase/metabolismo , Células Eritroides/enzimologia , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Técnicas de Silenciamento de Genes , Camundongos , Camundongos Knockout , MicroRNAs/genética , Alinhamento de Sequência , Deleção de Sequência/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
11.
Molecules ; 23(8)2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30042338

RESUMO

P-glycoprotein affects the transport of numerous drugs including chemotherapeutic drugs vincristine sulfate (VCR) and docetaxel (DTX), and is one of the main causes for multidrug resistance. Our previous studies have shown that oxypeucedanin (OPD) can enhance the intestinal transit of puerarin and VCR. However, the underlying mechanism is unclear. This study investigated the potential mechanism by which OPD improves P-gp-mediated drug transport. Molecular docking was performed to predict the binding force between OPD and P-gp and the contribution of OPD on P-gp activity. We observed the effect of OPD on the transport of VCR in MDCK-MDR1 cell monolayer and also measured the plasma pharmacokinetic parameters of DTX in the presence and absence of OPD by LC-MS/MS. Moreover, we further investigated the reversal mechanism of OPD on P-gp-mediated drug transport by determining the intracellular accumulation of Rhodamine-123 (Rh123) and P-gp ATPase activity as well as protein expression and mRNA level of P-gp. Our molecular docking results revealed that the binding force between OPD and P-gp was much lower than that between P-gp and verapamil (a P-gp substrate). The transport study in vitro indicated that OPD increased the flux of VCR across MDCK-MDR1 cell monolayer. The in vivo pharmacokinetic parameters data showed OPD increased the absorption of DTX. OPD activated P-gp ATPase activity and enhanced intracellular accumulation of Rh123 in MDCK-MDR1 cells. Western blotting and qRT-PCR outcomes indicated that OPD suppressed P-gp protein expression as well as downregulated P-gp mRNA level. Thus, OPD reverse P-gp-mediated drug transport via inhibition of P-gp activity and P-gp protein expression as well as downregulation of P-gp mRNA level. Our results suggest that OPD could reverse P-gp-mediated drug resistance in tumor cells.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Furocumarinas/farmacologia , RNA Mensageiro/antagonistas & inibidores , Taxoides/metabolismo , Vincristina/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Docetaxel , Cães , Resistência a Múltiplos Medicamentos/genética , Corantes Fluorescentes/metabolismo , Corantes Fluorescentes/farmacologia , Furocumarinas/química , Furocumarinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Cinética , Células Madin Darby de Rim Canino , Simulação de Acoplamento Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rodamina 123/metabolismo , Rodamina 123/farmacologia , Taxoides/farmacologia , Verapamil/metabolismo , Verapamil/farmacologia , Vincristina/farmacologia
12.
Zhongguo Zhong Yao Za Zhi ; 42(4): 795-799, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-28959855

RESUMO

To study the correlation of four properties of traditional Chinese medicine and the function of reversing multidrug resistance (MDR) of tumor cells, with 580 herbs in Chinese Pharmacopoeia 2015 version as the research objects. CNKI, CBA, Wanfang, VIP, and PubMed were searched to screen the documents related to the reversal of MDR for collection, summarizing and analysis. The results of the research showed that a total of 114 species Chinese herbs had been reported to be associated with reversal of MDR in tumor cells. Among 15 Chinese herbs with heat nature, 7 herbs had the function of reversing MDR in tumor cells, accounting for 46.7%. Among the 48 herbs with cool nature, 12 herbs had the function of reversing MDR, accounting for 25%. Among the 211 herbs with cold nature, 46 herbs had the function of reversing MDR, accounting for 21.8%. Among the 179 herbs with warm nature, 34 herbs had the function of reversing MDR, accounting for 19%. Among the 127 herbs with neutral nature, 15 herbs had the function of reversing MDR, accounting for 11.8%. Through the analysis on the relationship between four properties of 114 kinds of traditional Chinese medicines and reversing multidrug resistance of tumor cells, this paper speculated that there was a certain correlation between four properties of traditional Chinese medicine and the function of reversing multidrug resistance of tumor cells.


Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Linhagem Celular Tumoral , Humanos , Medicina Tradicional Chinesa
13.
Zhongguo Zhong Yao Za Zhi ; 42(10): 1894-1900, 2017 May.
Artigo em Chinês | MEDLINE | ID: mdl-29090548

RESUMO

The purpose of this study was to investigate the effect of key physical properties of hawthorn leaf granule on its dissolution behavior. Hawthorn leaves extract was utilized as a model drug. The extract was mixed with microcrystalline cellulose or starch with the same ratio by using different methods. Appropriate amount of lubricant and disintegrating agent was added into part of the mixed powder, and then the granules were prepared by using extrusion granulation and high shear granulation. The granules dissolution behavior was evaluated by using equilibrium dissolution quantity and dissolution rate constant of the hypericin as the indicators. Then the effect of physical properties on dissolution behavior was analyzed through the stepwise regression analysis method. The equilibrium dissolution quantity of hypericin and adsorption heat constant in hawthorn leaves were positively correlated with the monolayer adsorption capacity and negatively correlated with the moisture absorption rate constant. The dissolution rate constants were decreased with the increase of Hausner rate, monolayer adsorption capacity and adsorption heat constant, and were increased with the increase of Carr index and specific surface area. Adsorption heat constant, monolayer adsorption capacity, moisture absorption rate constant, Carr index and specific surface area were the key physical properties of hawthorn leaf granule to affect its dissolution behavior.


Assuntos
Crataegus/química , Medicamentos de Ervas Chinesas/análise , Extratos Vegetais/análise , Folhas de Planta/química , Química Farmacêutica , Tamanho da Partícula , Pós , Análise de Regressão , Solubilidade , Comprimidos
14.
Zhongguo Zhong Yao Za Zhi ; 42(24): 4870-4874, 2017 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29493160

RESUMO

The study was aimed to establish a liquid chromatography-tandem mass spectrometric method for the determination of the docetaxel concentration in rat plasma, and study the effect of coumarin constituents (imperatorin, isoimperatorin and oxypeucedanin) in Angelica dahurica on pharmacokinetics of docetaxel.Plasma was precipitated with acetonitrile and determined by LC-MS method with Paclitaxel as an internal standard. The specificity, linearity, range, accuracy, precision and stability of the method were suitable for the determination of docetaxel in plasma.Six sprague-dawley rats in each group received intragastric administration of docetaxel (50 mg•kg⁻¹), oxypeucedanin (8 mg•kg⁻¹) combined with docetaxel (50 mg•kg⁻¹), imperatorin (15 mg•kg⁻¹) combined with docetaxel (50 mg•kg⁻¹), and isoimperatorin(15 mg•kg⁻¹) combined with docetaxel (50 mg•kg⁻¹).Their drug plasma concentration was determined by LC-MS with Paclitaxel as an internal standard to draw plasma concentration-time curve, and the phamacokinetic parameters were calculated by DAS 2.0. The results showed that the phamacokinetic parameters of docetaxel all had notable changes when combined with imperatorin, isoimperatorin, and oxypeucedanin, respectively. The phamacokinetic parameters AUC and Cmax were significantly increased, indicating that coumarin constituents in Angelica dahurica could promote the oral bioavailability of docetaxel, and their effects were in the following order: oxypeucedanin> isoimperatorin> imperatorin.


Assuntos
Angelica/química , Docetaxel/farmacocinética , Furocumarinas/análise , Animais , Disponibilidade Biológica , Cromatografia Líquida , Espectrometria de Massas , Ratos
15.
Molecules ; 21(12)2016 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-27886150

RESUMO

P-glycoprotein (P-gp) affects the transport of many drugs; including puerarin and vincristine. Our previous study demonstrated that imperatorin increased the intestinal absorption of puerarin and vincristine by inhibiting P-gp-mediated drug efflux. However; the underlying mechanism was not known. The present study investigated the mechanism by which imperatorin promotes P-gp-mediated drug transport. We used molecular docking to predict the binding force between imperatorin and P-gp and the effect of imperatorin on P-gp activity. P-gp efflux activity and P-gp ATPase activity were measured using a rhodamine 123 (Rh-123) accumulation assay and a Pgp-Glo™ assay; respectively. The fluorescent probe 1,6-diphenyl-1,3,5-hexatriene (DPH) was used to assess cellular membrane fluidity in MDCK-MDR1 cells. Western blotting was used to analyze the effect of imperatorin on P-gp expression; and P-gp mRNA levels were assessed by qRT-PCR. Molecular docking results demonstrated that the binding force between imperatorin and P-gp was much weaker than the force between P-gp and verapamil (a P-gp substrate). Imperatorin activated P-gp ATPase activity; which had a role in the inhibition of P-gp activity. Imperatorin promoted Rh-123 accumulation in MDCK-MDR1 cells and decreased cellular membrane fluidity. Western blotting demonstrated that imperatorin inhibited P-gp expression; and qRT-PCR revealed that imperatorin down-regulated P-gp (MDR1) gene expression. Imperatorin decreased P-gp-mediated drug efflux by inhibiting P-gp activity and the expression of P-gp mRNA and protein. Our results suggest that imperatorin could down-regulate P-gp expression to overcome multidrug resistance in tumors.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Furocumarinas/farmacologia , Isoflavonas/metabolismo , Preparações de Plantas/farmacologia , Vincristina/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Angelica/química , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Difenilexatrieno/química , Cães , Células Madin Darby de Rim Canino , Simulação de Acoplamento Molecular , RNA Mensageiro/biossíntese
16.
Zhongguo Zhong Yao Za Zhi ; 41(12): 2245-2249, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-28901067

RESUMO

To study the improvement of powder flowability and hygroscopicity of traditional Chinese medicine extract by surface coating modification technology. The 1% hydrophobic silica nanoparticles were used as surface modifier, and andrographis extract powder was taken as a model drug. Three different techniques were used for coating model drugs, with angle of repose, compressibility, flat angle and cohesion as the comprehensive evaluation indexes for the powder flowability. The powder particle size and the size distribution were measured by Mastersizer 2000. FEI scanning electron microscope was used to observe the surface morphology and structure of the powder. The percentage of Si element on the powder surface was measured by energy dispersive spectrometer. The hygroscopicity of powder was determined by Chinese pharmacopoeia method. All of the three techniques can improve the flowability of powder extract. In particular, hygroscopicity of extract powder can also be improved by dispersion and then high-speed mixing, which can produce a higher percentage of Si element on the powder surface. The improvement principle may be correlated with a modifier adhered to the powder surface.


Assuntos
Medicamentos de Ervas Chinesas/química , Excipientes/química , Pós , Medicina Tradicional Chinesa , Tamanho da Partícula , Tecnologia Farmacêutica , Molhabilidade
17.
Zhongguo Zhong Yao Za Zhi ; 41(1): 60-64, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-28845641

RESUMO

To establish a method for the determination of chemical specific chromatograms and five components in Yinqiao powder decoction, and provide basis for elucidating the scientific connotation of ″taking in when the fragrance volatilized fiercely″. Yinqiao powder decoctions with different decocting times were prepared to study the changes of chemical components during decocting process. Specific chromatograms and contents of chlorogenic acid, phillyrin, arctiin, liquiritin and glycyrrhizin were determined by high performance liquid chromatography. According to the results, the similarities of Yinqiao powder decoctions with different decocting times were high, which indicated that their chemical compositions were similar. The dissolutions of the five components in Yinqiao powder reached more than 39.7% of 2 hour maximum dissolution amounts (MDA) after 20 minutes of soaking, more than 69.5% of MDA when boiling, more than 79.1% of MDA at the 5th minute after boiling, and more than 85.7% of MDA at the 10th minute after boiling. The concentrations of five components were not increasing obviously after 15 minutes of boiling (RSD<4.3%). The fragrance volatilized fiercely at about the 5th minute after boiling, which indicated that the contents of volatile components in Yinqiao powder decoctions were high, but it became weak after boiling for 15 minutes, which indicated that the contents of volatile components in Yinqiao powder decoctions were low. The results showed that the contents of five components in Yinqiao powder decoctions were heavily influenced by the decocting time. When boiling for about 5 minutes, the fragrance volatilized fiercely, both the contents of volatile components and non-volatile components were high. It is suggested that the traditional decocting method has a certain scientific basis.


Assuntos
Medicamentos de Ervas Chinesas/análise , Química Farmacêutica , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Flavanonas/análise , Glucosídeos/análise , Pós/análise
18.
Phytother Res ; 29(2): 220-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25312586

RESUMO

Radix Angelicae Dahuricae is the dried root of Angelicae Dahurica (Fisch.ex Hoffm.)Benth.et Hook.f. var.formosana (Boiss.) Shan et Yuan (Fam.Umbelliferae). The total coumarins (Cou) and volatile oil (VO) were main active components that drived from Radix Angelicae Dahuricae. Our previous studies have shown that Cou and VO could increase intestinal absorption for transmucosal drug delivery with unknown mechanism. The aim of this study was to investigate the molecular mechanism of Radix Angelicae Dahuricae for improving drug intestinal transport. Caco-2 cell model was used to study the effect of Radix Angelicae Dahurica on transepithelial electrical resistance. Western blot was used to study its effect on the expression of the actin and ZO-1, tight junction proteins. The effect of Radix Angelicae Dahurica on the expression of P-gp protein was investigated using flow cytometry. VO (0.036-2.88 µL/mL) and Cou (0.027-0.54 mg/mL) caused a reversible, time- and dose-dependent decrease in transepithelial electrical resistance. VO and/or Cou could inhibit the expression of the tight junction protein, ZO-1 and actin. VO and/or Cou also could inhibit the expression of P-gp. These data suggested that Radix Angelicae Dahurica increased cell permeability by affecting the expression of actin, ZO-1 or P-gp, opening the tight junction or inhibiting the efflux induced by P-gp.


Assuntos
Angelica/química , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacocinética , Absorção Intestinal/efeitos dos fármacos , Isoflavonas/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Actinas/metabolismo , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Cumarínicos/farmacologia , Humanos , Mucosa Intestinal/metabolismo , Óleos Voláteis/farmacologia , Raízes de Plantas/química , Junções Íntimas/efeitos dos fármacos , Proteína da Zônula de Oclusão-1/metabolismo
19.
Phytother Res ; 29(9): 1396-1403, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26074393

RESUMO

The objective of this study was to establish a quantitative method to evaluate the biotransportation of a drug across the cell membrane. Through the application of the law of mass conservation, the drug transportation rate was calculated based on Fick's law of passive diffusion and the Michaelis-Menten equation. The overall membrane-transportation rate was the sum of the passive diffusion rate and the carrier-mediated diffusion rate, which were calculated as the transportation mass divided by the respective rate. The active ingredients of Puerariae lobatae Radix and Chuanxiong rhizoma, namely, puerarin and ferulic acid, respectively, were used as two model drugs. The transportation rates of puerarin and ferulic acid were obtained by fitting a model that includes both Fick's law of diffusion and the Michaelis-Menten equation. Compared with the overall transportation, the carrier-mediated transport and passive diffusion of 1.59 mmol/L puerarin were -35.07% and 64.93%, respectively, whereas the respective transportation modes of 0.1 mmol/L ferulic acid were -35.40% and 64.60%, respectively. Verapamil and MK-571 increased the overall transport rate and ratio, and MK-571 treatment changed the carrier-mediated transport from negative to positive. However, the transport rate and ratio of ferulic acid did not change significantly. The cell transportation mechanisms of puerarin and ferulic acid primarily involve simple passive diffusion and carrier-mediated transportation. Moreover, P-glycoprotein and multidrug resistance-associated protein efflux proteins, and other transportation proteins were found to be involved in the transportation of puerarin. Copyright © 2015 John Wiley & Sons, Ltd.

20.
J Immunol ; 189(12): 5965-75, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23169590

RESUMO

MicroRNAs (miRNAs) are important posttranscriptional regulators in immune cells, but how viral infection regulates miRNA expression to shape dendritic cell (DC) responses has not been well characterized. We identified 20 miRNAs that were differentially expressed in primary murine DCs in response to the dsRNA agonist polyinosinic-polycytidylic acid, a subset of which were modestly regulated by influenza infection. miR-451 was unique because it was induced more strongly in primary splenic and lung DCs by live viral infection than by purified agonists of pattern recognition receptors. We determined that miR-451 regulates a subset of proinflammatory cytokine responses. Three types of primary DCs treated with antisense RNA antagomirs directed against miR-451 secreted elevated levels of IL-6, TNF, CCL5/RANTES, and CCL3/MIP1α, and these results were confirmed using miR-451(null) cells. miR-451 negatively regulates YWHAZ/14-3-3ζ protein levels in various cell types, and we measured a similar inhibition of YWHAZ levels in DCs. It is known that YWHAZ can control the activity of two negative regulators of cytokine production: FOXO3, which is an inhibitory transcription factor, and ZFP36/Tristetraprolin, which binds to AU-rich elements within 3'-untranslated regions to destabilize cytokine mRNAs. Inhibition of miR-451 expression correlated with increased YWHAZ protein expression and decreased ZFP36 expression, providing a possible mechanism for the elevated secretion of IL-6, TNF, CCL5/RANTES, and CCL3/MIP1α. miR-451 levels are themselves increased by IL-6 and type I IFN, potentially forming a regulatory loop. These data suggest that viral infection specifically induces a miRNA that directs a negative regulatory cascade to tune DC cytokine production.


Assuntos
Citocinas/biossíntese , Células Dendríticas/imunologia , Células Dendríticas/virologia , MicroRNAs/fisiologia , Animais , Linhagem Celular Tumoral , Citocinas/antagonistas & inibidores , Células Dendríticas/metabolismo , Regulação para Baixo/imunologia , Regulação Viral da Expressão Gênica/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Melanoma Experimental/virologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Cultura Primária de Células , Regulação para Cima/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA