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1.
Mar Drugs ; 11(4): 1113-25, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23549283

RESUMO

This study was aimed at developing a sensitive and selective HPLC method with postcolumn fluorescence derivatization for the detection of propylene glycol alginate sodium sulfate (PSS) in rat plasma. Plasma samples were prepared by a simple and fast ultrafiltration method. PSS was extracted from rat plasma with D-glucuronic acid as internal standard. Isocratic chromatographic separation was performed on a TSKgel G2500 PWxL column with the mobile phase of 0.1 M sodium sulfate at a flow rate of 0.5 mL/min. Analyte detection was achieved by fluorescence detection (FLD) at 250 nm (excitation) and 435 nm (emission) using guanidine hydrochloride as postcolumn derivatizing reagent in an alkaline medium at 120 °C. The calibration curve was linear over a concentration range of 1-500 µg/mL, and the lower limit of detection (LLOD) was found to be 250 ng/mL. This validated method was applied successfully to the pharmacokinetic study of PSS and PSS-loaded poly lactic-co-glycolic acid (PLGA) nanoparticles (PSS-NP) in rat plasma after a single intravenous (PSS only) and oral administration (PSS and PSS-NP). Significant differences in the main pharmacokinetic parameters of PSS and PSS-NP were observed. The relative bioavailability of PSS-NP was 190.10% compared with PSS which shows that PSS-NP can improve oral bioavailability.


Assuntos
Alginatos/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Ácido Láctico/química , Nanopartículas , Ácido Poliglicólico/química , Administração Oral , Alginatos/análise , Alginatos/química , Animais , Disponibilidade Biológica , Calibragem , Feminino , Fluorescência , Injeções Intravenosas , Limite de Detecção , Masculino , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Wistar , Sulfatos/química
2.
Chemistry ; 18(49): 15676-82, 2012 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-23080514

RESUMO

Monodisperse poly(acrylic acid)-modified Fe(3)O(4) (PAA@Fe(3)O(4)) hybrid microspheres with dual responses (magnetic field and pH) were successfully fabricated. The PAA polymer was encapsulated into the inner cavity of Fe(3)O(4) hollow spheres by a vacuum-casting route and photo-initiated polymerization. TEM images show that the samples consist of monodisperse porous spheres with a diameter around 200 nm. The Fe(3)O(4) spheres, after modification with the PAA polymer, still possess enough space to hold guest molecules. We selected doxorubicin (DOX) as a model drug to investigate the drug loading and release behavior of as-prepared composites. The release of DOX molecules was strongly dependent on the pH value due to the unique property of PAA. The HeLa cell-uptake process of DOX-loaded PAA@Fe(3)O(4) was observed by confocal laser scanning microscopy (CLSM). After being incubated with HeLa cells under magnet magnetically guided conditions, the cytotoxtic effects of DOX-loaded PAA@Fe(3)O(4) increased. These results indicate that pH-responsive magnetic PAA@Fe(3)O(4) spheres have the potential to be used as anticancer drug carriers.


Assuntos
Resinas Acrílicas/química , Antineoplásicos/química , Sistemas de Liberação de Medicamentos/métodos , Compostos Férricos/química , Polímeros/química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Campos Magnéticos
3.
Gastroenterol Res Pract ; 2019: 2651450, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31097959

RESUMO

OBJECTIVE: This study was conducted to compare a lactulose oral solution with a polyethylene glycol (PEG) formulation for colonoscopy preparation using the following metrics: quality of cleansing, colonoscopy outcomes, patient/physician satisfaction, and patient tolerability. METHODS: The enrolled patients were randomly divided into two groups and received a single 2 L dose of either PEG (PEG group) or lactulose (Lac group). The Boston Bowel Preparation Scale (BBPS) was used for assessing the cleansing quality of the bowel preparations. Patient tolerability and adverse events were obtained through the completion of questionnaires. RESULTS: The lactulose oral solution showed superior bowel cleansing compared to PEG, as evidenced by higher BBPS scores in the Lac group for all segments of the colon (P < 0.05). The detection rates of polyps and intestinal lesions in the Lac group (30.68% and 36.36%, respectively) were significantly higher than those in the PEG group (12.50% vs. 13.63%, respectively). For the degree of satisfaction, the Lac group had significantly higher scores compared to the PEG group, as evaluated by both the patients and endoscopist. PEG was associated with an increased incidence of nausea. There were no statistical differences between the groups in terms of vomiting, abdominal pain or fullness, dizziness, unfavorable palatability, dry mouth, palpitation, tinnitus, and tongue numbness. CONCLUSION: A single 2 L dose of a lactulose oral solution had higher efficacy, improved tolerability, and acceptable safety for bowel preparation when compared to the same volume of PEG. Thus, a lactulose oral solution may be a potential bowel-cleansing option for colonoscopy preparation.

4.
Chem Asian J ; 9(2): 506-13, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24227257

RESUMO

Multifunctional, mesoporous, silica-coated upconversion luminescent/magnetic NaGdF4:Yb/Er@NaGdF4:Yb@mSiO2-PEG (referred to as UCNPS; PEG=polyethylene glycol) nanocomposites were fabricated through a phase-transfer-assisted surfactant-templating coating process, followed by hydrophilic polymer (PEG) functionalization to improve the stability and biocompatibility. The UCNP core imparts the nanomaterials with luminescence and magnetic properties for simultaneous upconversion optical and magnetic resonance (MR) imaging, whereas the mesoporous shell affords the nanomaterials the ability to load the anticancer drug doxorubicin. Proof-of-principle in vitro and in vivo experiments are presented to demonstrate that the resultant composite nanomaterials can serve as nanotheranostics for synchronous upconversion luminescence/MR dual modal imaging and anticancer drug delivery; this finally realizes the integration of diagnostics and the treatment of cancers.


Assuntos
Portadores de Fármacos/química , Fluoretos/síntese química , Nanocompostos/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/química , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/toxicidade , Érbio/química , Fluoretos/química , Gadolínio/química , Células HeLa , Humanos , Imageamento por Ressonância Magnética , Magnetismo , Camundongos , Nanopartículas/química , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Polietilenoglicóis/química , Porosidade , Itérbio/química
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