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2.
Bioorg Med Chem Lett ; 30(4): 126927, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31901382

RESUMO

A series of xanthone derivatives were designed, synthesized and evaluated as multifunctional ligands against Alzheimer's disease (AD). In vitro studies showed all xanthone derivatives had good metal chelating property and exhibited selective inhibitory activity against Acetylcholinesterase (AChE). In particular, compound 2a showed the highest inhibitory activity against AChE, and the IC50 value was (0.328 ± 0.001) µM, which was comparable to tacrine. Kinetic analysis and molecular docking studies indicated that these derivatives targeted both the catalytically active site (CAS) and the peripheral anion site (PAS) of AChE. Moreover, all derivatives showed higher anti-oxidative activity than vitamin C. Furthermore, copper complex had higher anti-AChE activity and antioxidant activity. Thus, these xanthone derivatives are potential multi-targeted-directed ligands for further development for the treatment of AD.

3.
J Ethnopharmacol ; 249: 112407, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31751652

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Persicaria orientalis (L.) Spach (internationally accepted and only valid name; synonym: Polygonum orientale L.; family: Polygonaceae), which is named Hongcao in China, is a Chinese herbal medicine that has a wide range of pharmacological effects including treatment to rheumatoid arthritis, coronary heart disease, hernia, carbuncle sore, enhance immunity, antimicrobial, osteogenic and dilated bronchiectasis. AIM OF THIS REVIEW: This review aims to provide systematically organized information on traditional uses of Persicaria orientalis (L.) Spach (P. orientalis) and to critically analyze evidences in phytotherapeutic, botanical, and pharmacological literatures that support its therapeutic potential in treatment to human diseases. Isolation of additional compounds and detailed pharmacological investigations are key areas to investigate. MATERIALS AND METHODS: Relevant information on P. orientalis was collected through published scientific materials (including PubMed, ScienceDirect, Wiley, ACS, CNKI, Scifinder, Springer, Taylor & Francis, Web of Science, Google Scholar, and Baidu Scholar) and other literature sources (e.g., Chinese Pharmacopoeia, 2015 edition, Chinese herbal classic books and PhD and MSc thesis, etc.). RESULTS: Traditional uses were compiled in this review, including classic prescriptions and historical applications. Approximately 70 compounds, mainly including flavonoids, phenolics, lignans, limonoids and steroids, have been isolated and identified from P. orientalis. Among them, flavonoids were main components. Crude extracts and pure compounds isolated from P. orientalis exhibited various pharmacological activities, such as protection against ischemia and hypoxia-induced myocardial cells and hypoxia/reoxygenation cardiomyocyte, increase the blood flow in myocardium, expanding bronchus, anti-inflammatory and analgesic, and antithrombotic effects and so on. CONCLUSIONS: P. orientalis is a valuable source with therapeutic potential on a wide range of diseases especially cardiovascular-system disorders. Though most traditional uses of P. orientalis are supported by in vitro/vivo pharmacological studies, however, there is still a lack of researches on active pharmacodynamic ingredients as well as in-depth and in-vivo mechanistic studies. Therefore, isolation and identification of more active compounds (especially flavonoids), their structure-activity relationship and studies on pharmacodynamic mechanisms by more elaborative in-vivo studies on P. orientalis may be focused on in order to confirm efficacy of reported therapeutic effects of P. orientalis and help explore it's therapeutic potentials. Furthermore, research designs of pharmacological studies based on traditional uses of anti-rheumatoid arthritis through cell lines and animal models should also be considered as key research topics.

4.
Nat Immunol ; 21(2): 168-177, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31873294

RESUMO

Group 3 innate lymphoid cell (ILC3)-mediated production of the cytokine interleukin-22 (IL-22) is critical for the maintenance of immune homeostasis in the gastrointestinal tract. Here, we find that the function of ILC3s is not constant across the day, but instead oscillates between active phases and resting phases. Coordinate responsiveness of ILC3s in the intestine depended on the food-induced expression of the neuropeptide vasoactive intestinal peptide (VIP). Intestinal ILC3s had high expression of the G protein-coupled receptor vasoactive intestinal peptide receptor 2 (VIPR2), and activation by VIP markedly enhanced the production of IL-22 and the barrier function of the epithelium. Conversely, deficiency in signaling through VIPR2 led to impaired production of IL-22 by ILC3s and increased susceptibility to inflammation-induced gut injury. Thus, intrinsic cellular rhythms acted in synergy with the cyclic patterns of food intake to drive the production of IL-22 and synchronize protection of the intestinal epithelium through a VIP-VIPR2 pathway in ILC3s.

5.
Regen Med ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829095

RESUMO

Aim: To determine the efficacy and safety of intracoronary infusion of autologous bone marrow mesenchymal stem cells (MSCINJ) in combination with intensive atorvastatin (ATV) treatment for patients with anterior ST-segment elevation myocardial infarction-elevation myocardial infarction. Patients & methods: The trial enrolls a total of 100 patients with anterior ST-elevation myocardial infarction. The subjects are randomly assigned (1:1:1:1) to receive routine ATV (20 mg/d) with placebo or MSCsINJ and intensive ATV (80 mg/d) with placebo or MSCsINJ. The primary end point is the absolute change of left ventricular ejection fraction within 12 months. The secondary end points include parameters in cardiac function, remodeling and regeneration, quality of life, biomarkers and clinical outcomes. Results & conclusion: The trial will implicate the essential of cardiac micro-environment improvement ('fertilizing') for cell-based therapy. Clinical Trial Registration: NCT03047772.

6.
Acta Trop ; 202: 105256, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31682815

RESUMO

In recent years, attractive toxic sugar bait has been used in the mosquito control in nature, and achieved good control effects. However, the current researches about toxic sugar bait did not focus on whether the wild mosquito population used for control is resistant or not. The purpose of this study was to evaluate the effectiveness of the toxic sugar bait against mosquito resistant populations to test the effects of bait on the control of mosquitoes with different levels of resistance. Boric acid, dinotefuran and deltamethrin were separately formulated into toxic sugar bait to test their anti-mosquito activity against Culex quinquefasciatus. Using the sugar baits formulated with boric acid and dinotefuran, the mortality of Cx. quinquefasciatus resistant populations was significantly higher than that of sensitive populations at the same concentration. Conversely, with the use of sugar baits formulated with deltamethrin, the mortality of Cx. quinquefasciatus resistant populations was significantly lower than that of sensitive populations at the same concentration. The results suggested that toxic sugar baits might have a good application prospect in high resistant mosquito management.

7.
J Neurol Sci ; 407: 116507, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31644991

RESUMO

BACKGROUND: Clinical tools predicting brain edema after reperfusion therapy in acute ischemic stroke are scarce. We aim to develop a nomogram model to predict brain edema within the first 24 h after endovascular treatment (EVT) in the anterior cerebral circulation. METHODS: A total of 199 patients were retrospectively identified in a single-center stroke registry. Brain edema was measured by midline shift (MLS). The associations between MLS and early neurologic outcomes were described. A nomogram predicting MLS was developed and internally validated. The nomogram was also compared with an available model using the area under the receiver operating characteristic curve (AUC) and decision curve analyses. RESULTS: Overall, 87 patients (43.7%) had MLS. The patients with MLS ≥ 6 mm showed progressive neurological deterioration according to repeated measures analysis of variance. Each millimeter increase in MLS was strongly correlated with the presence of in-hospital death or forgoing treatment (Spearman's rho = 0.429, P < .001). Patients with brain edema were less likely to have functional independence at 3 months (19.5% vs. 46.8%, P < .001). A nomogram model including 24-h CT ASPECT scores and cisternal effacement, hypertension and complete recanalization showed a C-index of 0.874. This tool exhibited a higher AUC and higher net benefit than the available model. CONCLUSIONS: This study showed a profound association between MLS and early neurologic outcomes. A nomogram model was developed to predict patients at risk of brain edema after EVT in the anterior cerebral circulation.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31584868

RESUMO

A yellow, Gram-stain-negative, aerobic, non-gliding, non-spore-forming, rod-shaped strain, designated YIM 102600T, was isolated from the faeces of Macaca mulatta dwelling in the Yunnan Wild Animal Park, Yunnan Province, South-West PR China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 102600T was a member of the genus Flavobacterium, and closely related to Flavobacterium qiangtangense F3T (96.9 % similarity) and Flavobacterium noncentrifugens R-HLS-17T (96.0 % similarity). Phylogenetic trees showed that strain YIM 102600T formed a clade with F. qiangtangense F3T and F. noncentrifugens R-HLS-17T. Growth occurred at 4-30 °C (optimum, 28 °C), pH 7.0-8.0 (pH 7.5) and NaCl concentration 0-2 % (w/v; 0-1 %, w/v). The major fatty acids were iso-C15:0 and summed feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c). The predominant polar lipid was phosphatidylethanolamine and the sole respiratory quinone was menaquinone-6. The DNA G+C content was 36.4 mol%. The calculated digital DNA-DNA hybridization values between strain YIM 102600T and other species of Flavobacterium ranged from 70.0 to 75.0 % and average nucleotide identity values were in a range between 13.7 to 23.5 %. Based above the consensus of phenotypic and phylogenetic analyses as well as whole genome comparisons, strain YIM 102600T (=KCTC 52099T=CCTCC AB 201632T) is proposed to represent type strain of a novel species, Flavobacterium macacae sp. nov.

9.
Oxid Med Cell Longev ; 2019: 4591384, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531183

RESUMO

Background: Among all the common complications that occur after abdominal surgery, intestinal adhesion is perhaps the most unpleasant one. However, current methods to treat and prevent intestinal adhesion are limited; thus, exploring new methods to prevent and treat intestinal adhesion is greatly needed. In this study, we demonstrated that Danhong injection (DHI) may be used as a promising method to prevent and treat intra-abdominal adhesion in a rat model. Materials and Methods: Forty-eight rats were randomly divided into six groups. Except for the sham-operated group, all rats underwent cecal abrasion to establish an adhesion model. After the operation, the rats in the DHI-treated groups received different doses of DHI via the tail vein daily, while the other group was treated with the same volume of saline solution. Seven days after the operation, all rats were sacrificed, and the degree of adhesion was evaluated by Nair's scoring system. The extent of inflammation in the adhesion tissue was detected by HE staining and the expression of tumor necrosis factor-α (TNF-α) and transforming growth factor-ß (TGF-ß). The collagen deposition was assessed by Sirius red staining and α-SMA, MMP9, t-PA, and PAI-1 levels. Oxidative stress was indicated by the level of reactive oxygen species (ROS) in adhesion tissues and by immunohistochemical labeling of Nrf2. Furthermore, rat primary peritoneal mesothelial cells (RPMCs) were treated with H2O2 and DHI, and NF-κB phosphorylation was detected to illustrate the effect of DHI on oxidative stress. Results: The intra-abdominal adhesion scores were significantly decreased in the groups treated with a high dose of DHI compared with the control groups, and the degree of inflammation, fibrosis, and oxidative stress was also significantly decreased. DHI treatment significantly reduced the levels of TNF-α, TGF-ß1, and PAI and increased the expression levels of MMP9, Nrf2, and t-PA in the adhesion tissues. ROS levels and NF-κB phosphorylation were significantly reduced in DHI-treated RPMCs compared with the control RPMCs. Conclusion: DHI alleviates the formation of postoperative intra-abdominal adhesions by inhibiting inflammation, collagen deposition, and oxidative stress in a rat model and may serve as a promising drug to prevent intra-abdominal adhesions.

10.
Biomacromolecules ; 20(9): 3303-3312, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31094501

RESUMO

Synthetic organogels/hydrogels are attracting growing interests due to their potential applications in biomedical fields, organic electronics, and photovoltaics. Photogelation methods for synthesis of organogels/hydrogels have been shown particularly promising because of the high efficiency and simple synthetic procedures. This study synthesized new biodegradable polyhydroxyalkanoates (PHA)-based organogels/hydrogels via UV photo-cross-linking using unsaturated PHA copolymer poly[(R)-3-hydroxyundecanoate-co-(R)-3-hydroxy-10-undecenoate] (PHU10U) with polyethylene glycol dithiol (PDT) as a photo-cross-linker. The PHU10U was synthesized by an engineered Pseudomonas entomophila and characterized via Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance (NMR), and 13C NMR. With decreasing the molar ratio of PHU10U to PDT, both the swelling ratio and pore size were decreased. Meanwhile, increasing densities of the gel networks resulted in a higher compressive modulus. Cell cytotoxicity studies based on the CCK-8 assay on both the PHU10U precursor and PHU10U/PDT hydrogels showed that the novel PHA-based biodegradables acting as hydrogels possess good biocompatibility.

11.
Metab Eng ; 54: 117-126, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30959245

RESUMO

Bacterial polyhydroxyalkanoates (PHA) are a family of intracellular polyester granules with sizes ranging from 100 to 500 nm. Due to their small sizes, it has been very difficult to separate the PHA granules from the bacterial broths. This study aims to engineer the PHA size control mechanism to obtain large PHA granular sizes beneficial for the separation. It has been reported that phasin (PhaP) is an amphiphilic protein located on the surface of PHA granules functioning to regulate sizes and numbers of PHA granules in bacterial cells, deletions on PhaPs result in reduced PHA granule number and enhanced granule sizes. Three genes phaP1, phaP2 and phaP3 encoding three PhaP proteins were deleted in various combinations in halophilic bacterium Halomonas bluephagenesis TD01. The phaP1-knockout strain generated much larger PHA granules with almost the same size as their producing cells without significantly affecting the PHA accumulation yet with a reduced PHA molecular weights. In contrast, the phaP2- and phaP3-knockout strains produced slightly larger sizes of PHA granules with increased PHA molecular weights. While PHA accumulation by phaP3-knockout strains showed a significant reduction. All of the PhaP deletion efforts could not form PHA granules larger than a normal size of H. bluephagenesis TD01. It appears that the PHA granular sizes could be limited by bacterial cell sizes. Therefore, genes minC and minD encoding proteins that block formation of cell fission rings (Z-rings) were over-expressed in various phaP deleted H. bluephagenesis TD01, resulting in large cell sizes of H. bluephagenesis TD01 containing PHA granules with sizes of up to 10 µm that has never been observed previously. It can be concluded that PHA granule sizes are limited by the cell sizes. By engineering a large cell morphology large PHA granules can be produced by PhaP deleted mutants.

12.
J Nucl Cardiol ; 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30993654

RESUMO

BACKGROUND: This study aimed to compare the accuracy of gated-SPECT (GSPECT) and gated-PET (GPET) in the assessment of left ventricular (LV) end-diastolic volumes (EDVs), end-systolic volumes (ESVs) and LV ejection fractions (LVEFs) among patients with prior myocardial infarction (MI). METHODS: One hundred and sixty-eight consecutive patients with MI who underwent GSPECT and GPET were included. Of them, 76 patients underwent CMR in addition to the two imaging modalities. The measurements of LV volumes and LVEF were performed using Quantitative Gated SPECT (QGS), Emory Cardiac Toolbox (ECTB), and 4D-MSPECT (4DM). RESULTS: The correlation between GPET, GSPECT, and CMR were excellent for LV EDV (r = 0.855 to 0.914), ESV (r = 0.852 to 0.949), and LVEF (r = 0.618 to 0.820), as calculated from QGS, ECTB, and 4DM. In addition, subgroup analysis revealed that EDV, ESV, and LVEF measured by GPET were accurate in patients with different extents of total perfusion defect (TPD), viable myocardium, and perfusion/metabolic mismatch. Furthermore, multivariate regression analysis identified that mismatch score was associated with the difference in EDV (P < 0.05) measurements between GPET and CMR. CONCLUSIONS: In patients with MI, LV volumes and LVEF scores measured by both GSPECT and GPET imaging were comparable to those determined by CMR, but should not be interchangeable in individual patients.

13.
J Sci Food Agric ; 99(8): 3886-3894, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30684279

RESUMO

BACKGROUND: Foxtail millet (Setaria italica) bran is a by-product of millet processing, rich in dietary fiber (DF) and has great application value. A comparative study was conducted to explore the differences in structural and functional properties among millet bran DF, soluble dietary fiber (SDF) and insoluble dietary fiber (IDF). RESULTS: There was a significant difference in the content of monosaccharides between SDF and IDF, in which xylose, arabinose and glucose were the main compositions. The results of scanning electron microscopy showed that DF and IDF had different forms of network structure, and SDF presented a sign of mutual adhesion. The total phenolic and flavonoid contents were 0.54 and 0.08 g kg-1 in SDF. Antioxidant activity of SDF was higher than that of IDF based on the evaluation of free radical scavenging and iron reducing capacity in vitro. Meanwhile, the glucose dialysis retardation index of IDF and SDF was 12.59% and 9.26% at 30 min, respectively. And, there was no significant difference in the adsorption capacity of glucose among different samples (P > 0.05). Furthermore, SDF had strong α-amylase inhibition (17.92% inhibition rate) and sodium cholate adsorption capacities; the adsorption amount was 16.76 g kg-1 in 2.00 g L-1 sodium cholate solution. CONCLUSION: Foxtail millet bran DF, especially SDF, has good functional properties and would be a suitable ingredient for health-beneficial food production. However, the relevant verification trials in vivo need to be carried out in the next steps. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/análise , Fibras na Dieta/análise , Extratos Vegetais/química , Setaria (Planta)/química , Adsorção , Antioxidantes/química , Flavonoides/química , Monossacarídeos/química , Fenóis/química , Colato de Sódio/química , Resíduos/análise
14.
Chem Commun (Camb) ; 55(8): 1120-1123, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30624441

RESUMO

An unprecedented zeolite supramolecular framework featuring truncated cuboctahedral and truncated octahedral cavities was self-assembled from tetrahedral metal-organic cationic cages and tetrahedral anions. This crystalline porous material could trap iodine and organic dye molecules, and its solid state spin-crossover behavior was affected by guest encapsulation.

15.
Psychiatry Res ; 272: 398-403, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30611025

RESUMO

This study estimated the prevalence, correlates, severity and functional impairment of disabilities attributed to neurotic disorders in the Chinese population. Data from a representative national sample of 2,526,145 non-institutionalized residents were obtained from the Second China National Sample Survey on Disabilities (CNSSD) in 2006. The data were analyzed to estimate prevalence, correlates, severity and functional impairment of disability attributable to neurotic disorders by gender, age, region, and other key socio-demographic and economic factors. The disability prevalence attributed to neurotic disorders was 0.032% (805/2,526,145) in China. Women, rural residents, unemployed job status, low education level and those who were divorced or widowed showed higher prevalence rates than their counterparts. Proportions of mild, moderate, severe and extremely severe of neurotic attributed disability only accounted for 78.48%, 9.14%, 6.5% and 5.9%, respectively. Finally, these findings provide evidence that, prevalence rates of disability attributable to neurotic disorders vary greatly among different population groups and regions. Multiple disabilities including disability attributable to neurotic disorders can bring much more impairment to individuals than disability attributable to neurotic disorder only.


Assuntos
Pessoas com Deficiência/psicologia , Transtornos Neuróticos/epidemiologia , Transtornos Neuróticos/psicologia , Adolescente , Adulto , Idoso , China/epidemiologia , Estudos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Neuróticos/diagnóstico , Prevalência , População Rural , Fatores Sexuais , Fatores Socioeconômicos , Viuvez/psicologia , Adulto Jovem
16.
Chem Commun (Camb) ; 55(6): 822-825, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30574963

RESUMO

A novel porphyrin-based porous organic polymer PPOP-1(Pd) with bifunctional catalytic sites was constructed via imine condensation of tetra(4-aminophenyl)porphyrin and acenaphthenequinone. PPOP-1(Pd) containing Pd(ii)-porphyrin and Pd(ii)-α-diimine moieties exhibits excellent catalytic activity and outstanding reusability for tandem catalytic reactions of C-H arylation and Suzuki coupling.

17.
Food Sci Technol Int ; 25(4): 282-294, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30551720

RESUMO

Normal pressure steaming, high pressure steaming, microwave, and frying are widely used to deactivate enzyme in the oats, but these thermal processing methods may affect the structural and functional properties of soluble dietary fiber, which contribute greatly to the health benefits of oat foods. The objective of this study was to evaluate the effects of four different thermal processing methods on the structural and functional properties of soluble dietary fiber from whole grain oats. The results showed that the thermal processing resulted in changes on nutritional components of whole grain oats. Especially dietary fiber components, the total dietary fiber, insoluble dietary fiber, and soluble dietary fiber content of heat-treated oats were significantly increased ( p < 0.05). Moreover, thermal processing can not only result in an increase in molecular weight and particle size, but also cause molecular aggregation and different functional properties of soluble dietary fiber. High pressure steaming-treated oat soluble dietary fiber displayed significantly higher swelling and emulsifying ( p < 0.05), but microwave-treated oat soluble dietary fiber exhibited the highest glucose, cholesterol, and sodium cholate adsorption capacities. These results might provide basic information to help to better understand the functionality of oat soluble dietary fiber and improve the process efficiency of oat foods with high nutritional qualities.


Assuntos
Avena/química , Fibras na Dieta , Grão Comestível/química , Manipulação de Alimentos , Temperatura Alta , Grãos Integrais/química , Colesterol , Glucose , Peso Molecular , Valor Nutritivo , Tamanho da Partícula , Pressão , Colato de Sódio
18.
Exp Ther Med ; 16(5): 4010-4018, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30344679

RESUMO

Cutaneous squamous cell carcinoma (cSCC) accounts for 20% of non-melanoma skin cancer worldwide. MicroRNAs (miRNAs or miRs) are a subtype of non-coding RNA associated with the progression of various types of human cancer. MiR-186 has been demonstrated to act as an oncogene in human tumors. However, the role of miR-186 in cSCC remains unclear. The expression of miR-186 and apoptotic protease activating factor 1 (APAF1) was examined using reverse transcription-quantitative polymerase chain reaction, western blotting and immunofluorescence. The correlation between miR-186 and APAF1 was determined using a dual-luciferase assay. Mimics or inhibitors of miR-186 were transfected into A-431 cells to establish cell lines with overexpressed or knocked-down miR-186, respectively. EdU staining and colony formation assays were performed to detect cell proliferation. Transwell and wound-healing assays were performed to analyze cell invasion and migration, respectively. Hoechst staining and flow cytometry were performed to assess cell apoptosis and cell cycle distribution. MiR-186 expression was significantly increased, while APAF1 expression was significantly decreased in cSCC tissues compared with the controls. An miR-186 binding site was predicted in APAF1 and their expression was negatively correlated in cSCC tissues. Cell proliferation, invasion and migration were significantly enhanced in the miR-186-overexpressed A-431 cells and attenuated in miR-186 knockdown cells compared with the control. APAF1 expression was regulated by miR-186, while APAF1 knockdown significantly promoted cell invasion and inhibited cell apoptosis. In summary, the results of the present study indicate that miR-186 serves as an oncogene in cSCC by inhibiting APAF1.

19.
J Nanobiotechnology ; 16(1): 76, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30290822

RESUMO

BACKGROUND: Recently, we found that berberine (BBR) exerts anti-acute myeloid leukemia activity, particularly toward high-risk and relapsed/refractory acute myeloid leukemia MV4-11 cells in vitro. However, the poor water solubility and low bioavailability observed with oral BBR administration has limited its clinical use. Therefore, we design and develop a novel oil-in-water self-nanoemulsifying system for BBR (BBR SNE) to improve oral bioavailability and enhance BBR efficacy against acute myeloid leukemia by greatly improving its solubility. RESULTS: This system (size 23.50 ± 1.67 nm, zeta potential - 3.35 ± 0.03 mV) was prepared with RH40 (surfactant), 1,2-propanediol (co-surfactant), squalene (oil) and BBR using low-energy emulsification methods. The system loaded BBR successfully according to thermal gravimetric, differential scanning calorimetry, and Fourier transform infrared spectroscopy analyses. The release profile results showed that BBR SNE released BBR more slowly than BBR solution. The relative oral bioavailability of this novel system in rabbits was significantly enhanced by 3.41-fold over that of BBR. Furthermore, Caco-2 cell monolayer transport studies showed that this system could help enhance permeation and prevent efflux of BBR. Importantly, mice with BBR SNE treatment had significantly longer survival time than BBR-treated mice (P < 0.001) in an MV4-11 engrafted leukemia murine model. CONCLUSIONS: These studies confirmed that BBR SNE is a promising therapy for acute myeloid leukemia.


Assuntos
Absorção Fisiológica , Berberina/uso terapêutico , Emulsões/química , Leucemia Mieloide Aguda/tratamento farmacológico , Nanopartículas/química , Administração Oral , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Berberina/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citarabina/farmacologia , Citarabina/uso terapêutico , Interações de Medicamentos , Liberação Controlada de Fármacos , Leucemia Mieloide Aguda/patologia , Camundongos , Nanopartículas/ultraestrutura , Permeabilidade , Transição de Fase , Coelhos , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Nanoscale ; 10(39): 18492-18501, 2018 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-30132773

RESUMO

Quasi-one-dimensional semiconducting materials have attracted increasing attention due to their excellent ability to downscale the size of transistors. However, in quasi-one-dimensional nanowire (NW) transistors, their surface and interface properties play a very important role mainly due to the large surface-to-volume ratio of NWs and surface scattering, which degrade their carrier mobility. Herein, we developed a new method to cover the channel surface of InAs NW field effect transistors (FETs) with Y2O3/HfO2 layers to improve their electrical properties. We successfully fabricated nine FETs and measured their electrical properties, which improve after depositing the Y2O3/HfO2 layers, including an increase in on-state current, decrease in off-state current, increase in transconductance, increase in electron mobility and decrease in subthreshold swing. By comparing the properties of Y2O3/HfO2-covered devices with that of the FETs fabricated without the Y2O3 covering or without annealing, we prove that it is the combined Y2O3/HfO2 layers instead of only the Y2O3 or HfO2 layer that improve the electrical properties of the FETs. The Cs-corrected high-resolution scanning transmission electron microscopy study demonstrates that Y can actually diffuse through the native oxide layer (confirmed to be InOx) and reach the surface of the InAs NWs. Our results indicate that the desirable characteristics of Y2O3 and the surface passivation by HfO2 improve the electrical properties of the InAs NW FETs, in which Y2O3 plays an important role to modify and stabilize the interface between the InAs NWs and the outside dielectric layer. Furthermore, this method should also be applicable to other III-V materials.

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