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1.
Pharmacol Res ; 169: 105658, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33992797

RESUMO

Pancreatic cancer is one of the most aggressive cancers with a poor prognosis and 5-year low survival rate. In the present study, we report that bruceine A, a quassinoid found in Brucea javanica (L.) Merr. has a strong antitumor activity against human pancreatic cancer cells both in vitro and in vivo. Human proteome microarray reveals that 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 4 (PFKFB4) is the candidate target of bruceine A and both fluorescence measurement and microscale thermophoresis suggest bruceine A binds to PFKFB4. Bruceine A suppresses glycolysis by inhibiting PFKFB4, leading to cell cycle arrest and apoptosis in MIA PaCa-2 cells. Furthermore, glycogen synthase kinase-3 ß (GSK3ß) is identified as a downstream target of PFKFB4 and an PFKFB4-interacting protein. Moreover, bruceine A induces cell growth inhibition and apoptosis through GSK3ß, which is dysregulated in pancreatic cancer and closely related to the prognosis. In all, these findings suggest that bruceine A inhibits human pancreatic cancer cell growth via PFKFB4/GSK3ß-mediated glycolysis, and it may serve as a potent agent for curing human pancreatic cancer.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Fosfofrutoquinase-2/metabolismo , Quassinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia de Fluorescência , Transplante de Neoplasias , Neoplasias Pancreáticas/metabolismo , Reação em Cadeia da Polimerase , Quassinas/farmacologia
2.
Int J Pharm ; 658: 124180, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38705246

RESUMO

During the past several decades, nanostructures have played their increasing influences on the developments of novel nano drug delivery systems, among which, double-chamber Janus nanostructure is a popular one. In this study, a new tri-channel spinneret was developed, in which two parallel metal capillaries were nested into another metal capillary in a core-shell manner. A tri-fluid electrospinning was conducted with a solvent mixture as the shell working fluid for ensuring the formation of an integrated Janus nanostructure. The scanning electronic microscopic results demonstrated that the resultant nanofibers had a linear morphology and two distinct compartments within them, as indicated by the image of a cross-section. Fourier Transformation Infra-Red spectra and X-Ray Diffraction patterns verified that the loaded poorly water-soluble drug, i.e. icariin, presented in the Janus medicated nanofibers in an amorphous state, which should be attributed to the favorable secondary interactions between icariin and the two soluble polymeric matrices, i.e. hydroxypropyl methyl cellulose (HPMC) and polyvinylpyrrolidone (PVP). The in vitro dissolution tests revealed that icariin, when encapsulated within the Janus nanofibers, exhibited complete release within a duration of 5 min, which was over 11 times faster compared to the raw drug particles. Furthermore, the ex vivo permeation tests demonstrated that the permeation rate of icariin was 16.2 times higher than that of the drug powders. This improvement was attributed to both the rapid dissolution of the drug and the pre-release of the trans-membrane enhancer sodium lauryl sulfate from the PVP side of the nanofibers. Mechanisms for microformation, drug release, and permeation were proposed. Based on the methodologies outlined in this study, numerous novel Janus nanostructure-based nano drug delivery systems can be developed for poorly water-soluble drugs in the future.


Assuntos
Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Flavonoides , Derivados da Hipromelose , Nanofibras , Povidona , Solventes , Nanofibras/química , Animais , Solventes/química , Povidona/química , Flavonoides/química , Flavonoides/administração & dosagem , Flavonoides/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Derivados da Hipromelose/química , Solubilidade , Absorção Cutânea , Masculino , Ratos
3.
Int J Pharm ; 651: 123742, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38151102

RESUMO

Skin graft rejection is a significant challenge in skin allografts for skin defects, particularly in extensive burn injury patients when autografts are insufficient. Enhancing the survival duration of allogeneic skin grafts can improve the success rate of subsequent autologous skin grafting, thereby promoting the therapeutic efficacy for wound healing. Rapamycin (Rapa), a potent immunosuppressant with favorable efficacy in organ transplantation, is limited by its systemic administration-associated toxicity and side effects. Therefore, addressing the short survival time of allogeneic skin grafts and minimizing the toxicity related to systemic application of immunosuppressive agents is an urgent requirement. Here, we present a topical formulation based on bioadhesive poly (lactic acid)-hyperbranched polyglycerol nanoparticles (BNPs) with surface-modified encapsulation of Rapamycin (Rapa/BNPs), applied for local immunosuppression in a murine model of allogeneic skin grafts. Our Rapa/BNPs significantly prolong nanoparticle retention, reduce infiltration of T lymphocytes and macrophages, decrease the level of pro-inflammatory cytokines and ultimately extend skin allograft survival with little systemic toxicity compared to free Rapa or Rapamycin-loaded non-bioadhesive nanoparticles (Rapa/NNPs) administration. In conclusion, Rapa/BNPs effectively deliver local immunosuppression and demonstrate potential for enhancing skin allograft survival while minimizing localized inflammation, thus potentially increasing patient survival rates for various types of skin defects.


Assuntos
Nanopartículas , Sirolimo , Humanos , Camundongos , Animais , Imunossupressores , Nanopartículas/uso terapêutico , Aloenxertos , Administração Cutânea
4.
Carbohydr Polym ; 278: 118950, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973766

RESUMO

Cancer is a complex disease, and blocking tumor angiogenesis has become one of the most promising approaches in cancer therapy. Here, an exopoly heteropolysaccharide (AQP70-2B) was firstly isolated from Akebia quinata. Monosaccharide composition indicated that the AQP70-2B was composed of rhamnose, glucose, galactose, and arabinose. The backbone of AQP70-2B consisted of →1)-l-Araf, →3)-l-Araf-(1→, →5)-l-Araf-(1→, →3,5)-l-Araf-(1→, →2,5)-l-Araf-(1→, →4)-d-Glcp-(1→, →6)-d-Galp-(1→, and →1)-d-Rhap residues. Based on the close relationship between selenium and anti-tumor activity, AQP70-2B was modified with selenium to obtain selenized polysaccharide Se-AQP70-2B. Then, a series of methods for analysis and characterization, especially scanning electron microscopy coupled with energy dispersive spectrometry (SEM-EDS), indicated that Se-AQP70-2B was successfully synthesized. Furthermore, zebrafish xenografts and anti-angiogenesis experiments indicated that selenization could improve the antitumor activity by inhibiting tumor cell proliferation and migration and blocking angiogenesis.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Frutas/química , Neovascularização Patológica/tratamento farmacológico , Polissacarídeos/farmacologia , Ranunculales/química , Selênio/química , Inibidores da Angiogênese/química , Inibidores da Angiogênese/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Configuração de Carboidratos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/patologia , Neovascularização Patológica/patologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Peixe-Zebra/embriologia
5.
Food Chem ; 341(Pt 2): 128290, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33039743

RESUMO

The effect of pulsed air-impingement jet drying (AID) on the sensory qualities of Shiitake mushroom was comprehensively examined compared with hot air drying (HAD) and vacuum freeze-drying (VFD). AID considerably improved the characteristic flavors (onion-like odor and umami) of dried mushrooms by partially inhibiting enzymatic and Maillard reactions. The texture characteristics (rehydration and shrinkage) of AID mushrooms had no significant difference to VFD ones and were better than HAD ones. AID combined the advantages of HAD and VFD technologies and outperformed HAD and VFD in terms of overall quality, though the total content of free amino acids and soluble sugars of AID mushrooms dropped slightly. In summary, AID is a promising drying technology for obtaining high sensory quality Shiitake mushrooms compared to prevailing drying methods.


Assuntos
Dessecação/métodos , Liofilização/métodos , Cogumelos Shiitake/química , Paladar , Aminoácidos/química , Aromatizantes/análise , Odorantes/análise
6.
Int J Pharm ; 596: 120203, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33497703

RESUMO

In nature, the combination of composition, structure, and shape determines the matter's functional performance to a large extent. Inspired by which, two electrospun Janus nanofiber formulations were created using side-by-side electrospinning in this work. Tamoxifen citrate (TAM) was used as a model drug and ethyl cellulose (EC) and polyvinylpyrrolidone K60 (PVP) as the polymer carrier matrices. The fibers have linear cylindrical morphologies and distinct Janus structures by scanning electron microscopy. One side of the fibers took a round shape, while the other was crescent-shaped. The drug was present in both polymer matrices in the form of amorphous solid dispersions, owing to strong intermolecular interactions between drug and polymer. In vitro dissolution tests demonstrated that both sets of fibers could provide biphasic drug release due to the difference in solubility of PVP and EC. The different shape of TAM-EC and TAM-PVP side of the Janus structure resulted in a considerable variation in the drug release profiles. The Janus structure with crescent TAM-PVP side and round TAM-EC side gave a more rapid burst release in the first phase of release, and slower sustained release in the second phase. This work thus reports a new strategy for systematically developing advanced functional nanomaterials based on both shape- and structure-performance relationships.


Assuntos
Nanofibras , Composição de Medicamentos , Liberação Controlada de Fármacos , Polímeros , Solubilidade
7.
Food Chem ; 310: 125854, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31784067

RESUMO

Zeaxanthin dipalmitate (ZDP) is a major non-saponified carotenoid in fully ripe fruits of Lycium barbarum L. In the present study, response surface methodology was used to optimize the ultrasonic-assisted extraction (UAE) conditions of carotenoids from the fruits of L. barbarum, and the optimal extraction conditions were determined as follows: ultrasonic power of 360 W, ultrasonic time of 40 min and the ratio of extraction solvent to sample of 30 mL/g. An actual value of ZDP content of 5.40 mg/g and short extraction time indicated the efficiency of UAE. Furthermore, a promising high-speed counter-current chromatography (HSCCC) method was established for the purification of ZDP from the fruits of L. barbarum. With a developed two-phase solvent system composed of n-hexane/dichloromethane/acetonitrile (10/3/7, v/v/v), ZDP with a purity of higher than 95% was successfully isolated from the crude extract. This is the first report on the purification of ZDP by using HSCCC.


Assuntos
Distribuição Contracorrente/métodos , Lycium/química , Palmitatos/isolamento & purificação , Sonicação , Xantofilas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Solventes/química
8.
Food Chem ; 331: 127352, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32652343

RESUMO

The influence of some additives, including metal ions, antioxidants, enzyme inhibitors and organic solvents, on the storage stability of four organophosphorus pesticides in cucumber samples were investigated. It was found that metal ions, including Al3+, Fe3+, and Co2+, increased the stability of dichlorvos, malathion, and chlorpyrifos. Conversely, Al3+, Fe3+, Fe2+, and Co2+ caused catalytic degradation of diazinon. With the addition of organic solvents (CH2Cl2, CHCl3, CCl4, CH3OH and CH3COCH3), remaining of diazinon residues was higher (16-54%) after storage for seven days. CCl4 was associated with the highest retention of malathion, diazinon, and chlorpyrifos (33%, 48% and 44%, respectively) in samples. SDS also stabilized the pesticides since residues were, again, higher (13-38%) after seven days storage. Furthermore, addition of Al3+ and Fe3+ decreased peroxidase (POD) activity and inhibited degradation of dichlorvos and malathion. After 14 days, lyophilization increased the pesticide residues remaining by 36%, 29%, and 58% for diazinon, malathion and chlorpyrifos, respectively. Overall, the stability of these pesticides during storage is impacted by water content and addition of exogenous substances. This could ensure higher quality of pesticide residue data in samples.


Assuntos
Cucumis sativus/química , Contaminação de Alimentos/análise , Armazenamento de Alimentos , Inseticidas/química , Compostos Organofosforados/química , Alumínio/química , Clorpirifos/análise , Clorpirifos/química , Diazinon/análise , Diazinon/química , Diclorvós/análise , Diclorvós/química , Aditivos Alimentares/química , Liofilização , Inseticidas/análise , Malation/análise , Malation/química , Compostos Organofosforados/análise , Oxirredutases/química , Peroxidases/química , Peroxidases/metabolismo , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/química , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Dodecilsulfato de Sódio/química , Água/química
9.
Carbohydr Polym ; 219: 201-209, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151517

RESUMO

Sodium alginate (SA) is a marine-derived biocompatible polysaccharide with huge reserves and polyisobutylene (PIB) is a saturated elastomer with gas barrier property, bio-inertness, and biocompatibility. Herein, we developed the biomass-based ASA-g-(THF5-b-PIB) graft copolymer/Ag (3-11 nm, 0.7-3.8%) nanocomposites formed in-situ via combination of transition of terminal groups in PIB chains with grafting-onto method. The above graft copolymers exhibit microphase separation by self-assembly for the difference in chemical structure from backbone and branches and annealing process as well. The crystallization morphology from backbone depends on the Mn,PIB and GN, changing from thin strip to rod-like crystal. The pH sensitivity happens in drug release behavior of ASA-g-(THF5-b-PIB) micelles, which reach 100% of drug-release within 40 h at pH = 7.4. The ASA-g-(THF5-b-PIB)/Ag composites behave good antibacterial properties to both E. coli and S. aureus and anti-protein adsorption performance. This novel graft copolymer with comprehensive properties and would have a prospect in biomedical field.

10.
Food Chem ; 275: 322-332, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724203

RESUMO

The potentialities of front-face fluorescence (FFF) and mid-infrared (MIR) spectroscopies coupled with partial least square regression (PLSR) were compared to predict the lipid oxidation of pound cakes. The level of lipid oxidation in pound cakes determined using classical methods showed some changes. Similarly, the fluorescence emission (305-490 nm) and excitation (252-390 nm) spectra and MIR spectra scanned in the 4000-700 cm-1 region showed some changes in pound cakes as a function of both storage time and the type of oil used in the formulation. The application of PLSR to the MIR spectra, provided excellent predictive results for free fatty acid (R2 = 0.97) and peroxide values (R2 = 0.87). Similar results were obtained from both tryptophan and MIR spectra for the prediction of TOTOX (R2 > 0.86) demonstrating the efficiency of the MIR and FFF spectroscopies to qualify and quantify the level of lipid oxidation in pound cakes.


Assuntos
Pão , Armazenamento de Alimentos/métodos , Lipídeos/química , Espectrometria de Fluorescência/métodos , Espectrofotometria Infravermelho/métodos , Análise dos Mínimos Quadrados , Oxirredução , Óleo de Palmeira , Óleo de Brassica napus , Espectrometria de Fluorescência/estatística & dados numéricos , Espectrofotometria Infravermelho/estatística & dados numéricos , Triptofano/química , Vitamina A/química
11.
Int J Pharm ; 547(1-2): 24-30, 2018 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-29800738

RESUMO

A delivery system based on poly(lactic-co-glycolic acid) polymer (PLGA) microparticles has been developed for parenteral administration of the local anesthetic prilocaine in its free base form. Both drug-free and drug-loaded microparticles, prepared by a double-emulsion-evaporation method, were characterized for mean size by Laser Diffraction Analysis, while their morphology was investigated by scanning electron microscopy. The preparation technique allowed obtainment of homogeneous microparticles of about 25 µm diameter, suitable for subcutaneous administration. The encapsulation efficiency, determined by both direct and indirect methods, was around 36-38%. Differential Scanning Calorimetry was used to characterize the solid state of the raw materials, assess drug-polymer compatibility and miscibility and highlight possible modifications of the components induced by the preparation method. In vitro release studies showed a sustained release profile, with about 80% of drug released after the first 24 h. The anesthetic effect of the formulation was evaluated in vivo on rats, according to the test of cutaneous trunci muscle reflex. Administration of prilocaine base as PLGA microparticles allowed to significantly enhance both extent (60% AUC increase) and duration (100% increase) of the anesthetic effect in the animal model, in comparison with the equivalent dose of prilocaine hydrochloride aqueous solution.


Assuntos
Anestésicos Locais/administração & dosagem , Portadores de Fármacos , Ácido Láctico/administração & dosagem , Ácido Poliglicólico/administração & dosagem , Prilocaína/administração & dosagem , Anestésicos Locais/química , Animais , Varredura Diferencial de Calorimetria , Composição de Medicamentos , Liberação Controlada de Fármacos , Ácido Láctico/química , Masculino , Microscopia Eletrônica de Varredura , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Prilocaína/química , Ratos Sprague-Dawley , Reflexo/efeitos dos fármacos
12.
Carbohydr Polym ; 190: 87-94, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29628263

RESUMO

A neutral water soluble polysaccharide (HPA) was isolated from the marine fungus Hansfordia sinuosae. Monosaccharide composition analysis indicated that HPA was mainly composed of mannose with minor amounts of galactose and glucose. The molecular weight of HPA was approximately 22.5 kDa as analyzed by HPGPC. Structure analysis of HPA with methylation and 1D, 2D NMR indicated that HPA was composed of [α-d-Manp(1→], [→2)-α-d-Manp(1→], [→3)-α-d-Manp(1→] and [→2,6)-α-d-Manp(1→] with [α-d-Manp(1→] linked to C-6 position of [→2,6)-α-d-Manp(1→]. The antitumor effect of HPA was evaluated in vitro. HPA showed remarkable inhibitory effect on human cervical carcinoma HeLa cells and human breast carcinoma MCF-7 cells. When cells were incubated with HPA at 400 µg/mL for 48 h, the inhibition rate on HeLa and MCF-7 cells was 79.5% and 73.8%, respectively. Furthermore, for HeLa cells, HPA could increase intracellular ROS levels, induce cells apoptosis, decrease mitochondrial membrane potential, and elevate the expression of caspase-3. The results suggested that HPA could be explored as a potential antitumor agent.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Ascomicetos/citologia , Espaço Extracelular/química , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Metilação/efeitos dos fármacos , Monossacarídeos/análise , Espécies Reativas de Oxigênio/metabolismo
13.
Food Chem ; 267: 10-14, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29934142

RESUMO

Mycotoxins, present in a wide range of food and feed commodities, are toxic secondary metabolites produced by a number of different fungi. Certain mycotoxins do not readily degrade at high temperatures, therefore are resistant to food processing, and consequently are present in the human and animal food supply. Optical waveguide lightmode spectroscopy (OWLS) was applied for the detection of aflatoxin B1, in a competitive immunoassay format, to compare the analytical sensitivity achieved with an immunosensor design allowing signal enhancement by increasing the sensor surface through immobilization of gold nanoparticles (AuNPs) of different size and origin (obtained by chemical or biotechnological synthesis). The effects of AuNPs median size, the methods of sensitization and the biochemical parameters on immunosensor performace were examined. After optimization of the sensitized sensor surface, an immunosensing method was developed for the analysis of aflatoxin in paprika matrix and the results were compared with HPLC reference measurements.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Micotoxinas/análise , Refratometria/métodos , Aflatoxina B1/análise , Capsicum/metabolismo , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Concentração de Íons de Hidrogênio , Lasers de Gás , Tamanho da Partícula , Soroalbumina Bovina/química
14.
Eur J Pharm Sci ; 122: 195-204, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-30008429

RESUMO

Structural nanocomposites that provide fast dissolving drug release profiles are highly in demand in pharmaceutics. In this study, a poorly water-soluble drug such as quercetin or tamoxifen citrate (TC) was selected as a model active pharmaceutical ingredient. Core-shell nanofibers with ultra-thin shells were designed and prepared using modified coaxial electrospinning. Polyvinylpyrrolidone (PVP) K90 or Polycaprolactone (PCL) was selected as core. The drugs and PVP K10 were selected as shell. All types of solutions can be used as the shell fluids in modified coaxial process regardless of their electrospinnability, which means the increasing functional ingredients and unspinnable matrix can be processed. Evaluations via SEM and TEM demonstrated that the core-shell nanofibers had linear morphology with a shell thickness smaller than 100 nm. XRD and FTIR results showed that the model drug was distributed in the polymeric matrix amorphously and that PVP K10 had good compatibility with quercetin or TC. In vitro dissolution tests suggested that the core-shell nanofibers with ultra-thin shells released the loaded cargoes in the dissolution media within 1 min. The present investigation paved a new way for implementing the modified coaxial processes, which can be utilized to fabricate structural nanocomposites with ultra-thin shells for enhancing the fast dissolution of poorly water-soluble drugs.


Assuntos
Sistemas de Liberação de Medicamentos , Membranas Artificiais , Nanocompostos/química , Liberação Controlada de Fármacos , Nanofibras/química , Poliésteres/química , Povidona/química , Quercetina/química , Tamoxifeno/química
15.
Neurochem Int ; 113: 8-22, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29174381

RESUMO

In the course of searching for anti-neuroinflammatory metabolites from marine-derived fungi, three fungal metabolites, 6,8,1'-tri-O-methylaverantin, 6,8-di-O-methylaverufin, and 5-methoxysterigmatocystin were isolated from a marine-derived fungal strain Aspergillus sp. SF-6796. Among these, 6,8,1'-tri-O-methylaverantin induced the expression of heme oxygenase (HO)-1 protein in BV2 microglial cells. The induction of HO-1 protein was mediated by the activation of nuclear transcription factor erythroid-2 related factor 2 (Nrf2), and was regulated by the p38 mitogen-activated protein kinase and phosphatidylinositol 3-kinase/protein kinase B signaling pathways. Furthermore, 6,8,1'-tri-O-methylaverantin suppressed the overproduction of pro-inflammatory mediators, such as nitric oxide, prostaglandin E2, inducible nitric oxide synthase, and cyclooxygenase-2 in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. These anti-neuroinflammatory effects were mediated through the negative regulation of the nuclear factor kappa B pathway, repressing the phosphorylation and degradation of inhibitor kappa B-α, translocation into the nucleus of p65/p50 heterodimer, and DNA-binding activity of p65 subunit. The anti-neuroinflammatory effect of 6,8,1'-tri-O-methylaverantin was partially blocked by a selective HO-1 inhibitor, suggesting that its anti-neuroinflammatory effect is at least partly mediated by HO-1 induction. In this study, 6,8,1'-tri-O-methylaverantin also induced HO-1 protein expression in primary microglial cells, and this correlated with anti-neuroinflammatory effects observed in LPS-stimulated primary microglial cells. In conclusion, 6,8,1'-tri-O-methylaverantin represents a potential candidate for use in the development of therapeutic agents for the regulation of neuroinflammation in neurodegenerative diseases.


Assuntos
Antraquinonas/metabolismo , Anti-Inflamatórios/metabolismo , Aspergillus/metabolismo , Heme Oxigenase-1/biossíntese , Proteínas de Membrana/biossíntese , Microglia/metabolismo , Regulação para Cima/fisiologia , Animais , Antraquinonas/isolamento & purificação , Antraquinonas/farmacologia , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Aspergillus/isolamento & purificação , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Lipopolissacarídeos/toxicidade , Camundongos , Microglia/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
16.
Int J Hyg Environ Health ; 220(7): 1133-1140, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28720343

RESUMO

BACKGROUND: The incidence of childhood cancers has been increasing and environmental exposure to air toxics has been suggested as a possible risk factor. This study aims to explore ambient exposure to dichloromethane (methylene chloride). METHODS: We frequency matched by birth year approximately 20 cancer-free controls identified from birth records to all childhood cancers ages 0-5 in the California Cancer Registry diagnosed from 1988 to 2012; i.e. 13,636 cases and a total of 270,673 controls. Information on industrial releases of dichloromethane within 3km of birth addresses was retrieved from mandatory industry reports to the EPA's Toxics Release Inventory (TRI). We derived exposure to dichloromethane within close vicinity of birth residences using several modeling techniques including unconditional logistic regression models with multiple buffer distances, inverse distance weighting, and quadratic decay models. RESULTS: We observed elevated risks for germ cell tumors [Odds Ratio (OR): 1.52, 95% Confidence Interval (CI) 1.11, 2.08], particularly teratomas (OR: 2.08, 95% CI 1.38-3.13), and possible increased risk for acute myeloid leukemias (AML) (OR: 1.64, 95% CI 1.15-2.32 in the quadratic decay model). Risk estimates were similar in magnitude whether releases occurred in pregnancy or the child's first year of life. CONCLUSION: Our findings suggest that exposure to industrial dichloromethane releases may be a risk factor for childhood germ cell tumors, teratomas, and possibly AML.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Leucemia Mieloide Aguda/induzido quimicamente , Leucemia Mieloide Aguda/epidemiologia , Exposição Materna/efeitos adversos , Cloreto de Metileno/efeitos adversos , Teratoma/induzido quimicamente , Teratoma/epidemiologia , Adolescente , Adulto , Poluição do Ar/efeitos adversos , California/epidemiologia , Estudos de Casos e Controles , Pré-Escolar , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Feminino , Humanos , Indústrias , Lactente , Modelos Logísticos , Masculino , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Neoplasias Embrionárias de Células Germinativas/induzido quimicamente , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Gravidez , Sistema de Registros , Fatores de Risco , Adulto Jovem
17.
Carbohydr Polym ; 174: 617-625, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28821112

RESUMO

Hypromellose (HPMC)-based hydrophilic composites (HCs) used for rapid dissolution of ferulic acid (FA) were investigated. Electrospun and casting HCs were prepared from a solution containing HPMC, FA, and polyethylene glycol. Ethanol was used as sheath fluid during coaxial processes, and the effects of its flow rates on the Taylor cone and straight fluid jet were investigated. The morphology, component state, hydrophilicity, and drug dissolution rate of the HCs were characterized. Results demonstrated that all HCs were amorphous materials, and their components were compatible. However, the dissolution rate of electrospun HCs was 10 times faster than that of casting HCs. The smaller the diameters of electrospun HCs were, the better their performances were. The mechanism of electrospun HCs was suggested. By utilizing modified coaxial electrospinning and combinations of drug carriers, new types of HPMC-based HCs can provide an alternative approach for the effective delivery of poorly water-soluble drugs.


Assuntos
Portadores de Fármacos/química , Derivados da Hipromelose/química , Ácidos Cumáricos , Interações Hidrofóbicas e Hidrofílicas , Polietilenoglicóis , Solubilidade , Água
18.
Carbohydr Polym ; 170: 247-253, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28521994

RESUMO

Enrofloxacin (ENRO) is widely used as an antimicrobial drug for treatment of uncomplicated and complicated infections in veterinary medicine. Its bitter taste limits its clinical applications in veterinary. To mask the bitter taste of this drug, double-coated taste-masking microparticles of ENRO (DTME) were prepared through stearic acid solid dispersion and chitosan-alginate microparticle coating technologies. The taste-masking effect was evaluated by pig feeding experiment. Results showed that DTME exhibited a spherical-like shape (170490µm). DTME yielded a drug loading rate of DTME 20.3% and an entrapment efficiency of 89.8%. The bitter detection threshold value of ENRO for pigs is 2µg/mL. The drug release amounts of DTME within 30s were less than 2µg/mL in artificial saliva. Compared with normal food intake, the food intake of pigs decreased 28.65% when fed with fodder containing free ENRO and slightly increased (0.18%) when fed with fodder containing DTME. Therefore, DTME masked the bitterness of ENRO and improved its palatability. In conclusion, DTME showed satisfactory bitter taste-masking property; this novel formulation was likely to provide more selectable dosage forms for ENRO.


Assuntos
Alginatos/química , Quitosana/química , Fluoroquinolonas/química , Animais , Enrofloxacina , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Nanopartículas/química , Paladar
19.
Eur J Pharm Biopharm ; 109: 174-183, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27793757

RESUMO

Cervical cancer is one of the most life threatening types of cancer among women and is generally resistant to chemotherapy. The objective of this study was to prepare a vaginal suppository containing a chemotherapeutic agent and a genetic material that can be applied locally for cervical cancer. Paclitaxel was selected as the chemotherapeutic agent and siRNA which inhibits BCL-2 oncogene was selected as the genetic material. Bcl-2 siRNA, paclitaxel and paclitaxel/Bcl-2 siRNA combination were incorporated into solid lipid nanoparticles (SLNs) and were dispersed separately in vaginal suppositories prepared with PEG 6000. Physicochemical properties of SLNs, their cytotoxicities on HeLa cell lines and also the effect of SLNs on the total protein amount of the cells were examined followed by the investigation of release rates of the active materials from the SLNs prepared. Average diameters of all SLNs prepared were below 180nm with a positive zeta potential value between +22.20 and +48.16mV at the pH range of 4.2 and 7.4. The release of Bcl-2 siRNA from SLNs incorporated Bcl-2 siRNA and the release of paclitaxel (PTX) from PTX incorporated SLNs were completed within 12h and 36h. SLNs incorporating Bcl-2 siRNA and paclitaxel/Bcl-2 siRNA were found to be more toxic when compared to paclitaxel incorporated SLN and placebo SLN. The disintegration of the vaginal suppositories as well as the release of the SLNs was completed within 2 h. This study indicates that vaginal suppository containing SLNs can bring the advantages of the simultaneous delivery of paclitaxel and siRNA via vaginal route with no help from professionals.


Assuntos
Administração Intravaginal , Paclitaxel/administração & dosagem , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Interferente Pequeno/genética , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Cromatografia Líquida de Alta Pressão , Colorimetria , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Feminino , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Lipídeos/química , Lipossomos/química , Nanopartículas/química , Paclitaxel/química , Tamanho da Partícula , Solventes , Supositórios/química
20.
J Ethnopharmacol ; 194: 98-107, 2016 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-27586821

RESUMO

BACKGROUND: Malaria remains a major health problem worldwide especially in sub-Saharan Africa. In Kenya, 80% of the population is at risk of contracting the disease. Pregnant mothers and children under five years are the most affected by this disease. Antimalarial drug resistance poses a major threat in the fight against malaria necessitating continuous search for new antimalarial drugs. Due to inadequate and inaccessible health facilities, majority of people living in rural communities heavily depend on traditional medicine which involves the use of medicinal plants for the management of malaria. Most of these indigenous knowledge is undocumented and risks being lost yet such information could be useful in the search of new antimalarial agents. AIM OF STUDY: An ethnobotanical survey was carried out among the Luhya community of Kakamega East sub-County, a malaria epidemic region, with the aim of documenting the plants used in the management of malaria. MATERIALS AND METHODS: Semi-structured questionnaires were used to collect information from 21 informants who included traditional medicine practitioners and other caregivers who had experience in use of plants in management of malaria. These were drawn from 4 villages located in Kakamega East sub-county, within Kakamega County based on their differences in topography. Information recorded included plant names, parts used, mode of preparation and administration and the sources of plant materials. A literature search was conducted using PubMed and google scholar to identify the reported traditional uses of these plants and studied antiplasmodial activities. RESULTS: In this study, 57% of the informants were aged above 50 years and a total of 61% had either no formal education or had only attained primary school education. A total of 42 plant species belonging to 24 families were identified. Most plants used in the management of malaria in this community belonged to Lamiaceae (18%), Leguminosae (9%) and Compositae (9%) plant families. Plants mostly used included Melia azedarach L, Aloe spp, Ajuga integrifolia Buch. Ham, Vernonia amygdalina Del., Rotheca myricoides (Hochst.) Steane and Mabb, Fuerstia africana T.C.E.Fr., Zanthoxylum gilletii (De Wild.) P.G.Waterman and Leucas calostachys Oliv. Rumex steudelii Hochst.ex A. Rich and Phyllanthus sepialis Müll. Arg are reported for the first time in the management of malaria. Although Clerodendrum johnstonii Oliv. (Jeruto et al., 2011) and Physalis peruviana L.(Ramadan et al., 2015) are reported in other studies for management of malaria, no studies have been carried out to demonstrate their antiplasmodial activity. The plant parts mostly used were the leaves (36%) and stem barks (26%). Majority of these plants were prepared as decoctions by boiling and allowed to cool before administration (66%) while infusions accounted for 28% of the preparations. The literature mined supports the use of these plants for the management of malaria since most of them have demonstrated in-vitro and in-vivo antiplasmodial activities. CONCLUSION: Most of the reported plant species in this study have been investigated for antiplasmodial activity and are in agreement with the ethnomedical use. Two (2) plants are reported for the first time in the management of malaria. There is need for documentation and preservation of the rich ethnomedical knowledge within this community given that most of the practitioners are advanced in age and less educated. There is also the danger of over-exploitation of plant species as most of them are obtained from the wild, mainly Kakamega forest. Therefore, there is need for determining the economically and medicinally important plants in this community and planning for their preservation.


Assuntos
Malária/terapia , Plantas Medicinais , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimaláricos/uso terapêutico , Feminino , Humanos , Quênia/epidemiologia , Malária/epidemiologia , Masculino , Medicinas Tradicionais Africanas , Pessoa de Meia-Idade , Adulto Jovem
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