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1.
An Acad Bras Cienc ; 92(1): e20190336, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32321026

RESUMEN

Uncaria tomentosa (UT) extracts have been shown to have promising anti-tumor activity. We hypothesized that its incorporation into nanostructured systems could improve the anticancer properties. Here, poly-e-caprolactone (PCL) and poly-d,l-lactide-co-glycolide (PLGA) were employed to generate nanoparticles loaded with UT extract in a single emulsion solvent evaporation method. The nanoparticles were characterized by particle size, zeta potential, morphology and entrapment efficiency along with stability and release profiles. The nanoparticles presented entrapment efficiencies above 60% and a mean diameter below 300nm. UT-PCL nanoparticles presented higher entrapment efficiency and mean particle size as well as a slow release rate. The UT-PLGA nanoparticles showed higher drug loading. Two prostate cancer cell-lines, LNCaP and DU145 that were derived from metastatic sites, served as model systems to assess cytotoxicity and anti-cancer activity. In vitro, both formulations reduced the viability of DU145 and LNCaP cells. Yet, the UT-PLGA nanoparticles showed higher cytotoxicity towards DU145 cells while the UTPCL against LNCaP cells. The results confirm that the incorporation of UT into nanoparticles could enhance its anti-cancer activities that can offer a viable alternative for the treatment of prostrate canner and highlights the potential of nanostructured systems to provide a promising methodology to enhance the activity of natural extracts.


Asunto(s)
Antineoplásicos/farmacología , Uña de Gato/química , Extractos Vegetales/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos , Humanos , Nanopartículas
2.
J Photochem Photobiol B ; 193: 162-171, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30884286

RESUMEN

Olive leaves contain higher amount of polyphenols than olive oil and represent a waste product from olive harvest and pruning of olive trees. The most abundant compound in olive leaves is oleuropein. Benefits of the topical application of olive leaves extract were previously reported, but little information is available on its photoprotective potential and the result of the association of this extract with organic UV filters in topical sunscreen formulations. The olive leaves extract photoprotective potential is less explored for both oral and topical photoprotection in comparison with other plants extracts and polyphenols, such as Polypodium leucotomos extract and resveratrol. There are increasing efforts towards developing more efficient sunscreens and a photoprotection assessement along with a better understanding of the photochemistry of naturally occurring sunscreens could aid the design of new and improved commercial sunscreen formulations. This study was designed to investigate the photoprotective potential of olive leaves extract standardized for oleuropein performing a set of in vitro and in silico tools as an innovative approach, highlighting yeast assays, in vitro Sun Protection Factor (SPF) and molecular modelling studies of UV absorption. This study supports the use of olive leaves extract for photoprotection, as an effective photoprotective, anti-mutagenic and antioxidant active, also showing a synergistic effect in association with UV filters with an improvement on in vitro SPF of sunscreen formulations.


Asunto(s)
Iridoides/química , Olea/química , Extractos Vegetales/química , Protectores Solares/química , Antioxidantes/química , Glucósidos Iridoides , Iridoides/aislamiento & purificación , Modelos Moleculares , Olea/metabolismo , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Teoría Cuántica , Factor de Protección Solar , Protectores Solares/aislamiento & purificación , Rayos Ultravioleta
3.
An Acad Bras Cienc ; 90(3): 3063-3073, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30043910

RESUMEN

Dietary supplements in many countries such as the USA do not require registration prior to commercialization. The Agência Nacional de Vigilância Sanitária (ANVISA) registers substances with functional properties as foods. Lutein is a carotenoid with antioxidant activity available on the market. However, no regulatory mandates exist to govern the design of quality control tests, which are necessary to ensure formulation effectiveness. Therefore, in the present study, tablet and dosage formulations from different manufacturers were tested following general methods outlined in the Brazilian and American Pharmacopeias. The averageweight, disintegration, content and dose uniformity assays were performed for all tablets and capsules, whereas hardness assays were only performed on tablets. None of the 10 formulations studied were found to be of satisfactory quality. Of all tablets tested, two had no-significant available lutein content, which may indicate adulteration. The capsules displayed adequate amounts of lutein, however had alarmingly negative disintegration and dissolution test results, which may contribute to non-bioavailability of lutein. All formulations analyzed are currently being marketed in the Brazilian and American markets. The low physicochemical performance in these formulations can be explained by the lack of specific regulations, which are necessary to ensure the quality of lutein-containing products on the market.


Asunto(s)
Cápsulas/normas , Suplementos Dietéticos/normas , Regulación Gubernamental , Luteína/normas , Comprimidos/normas , Disponibilidad Biológica , Brasil , Cápsulas/química , Fenómenos Químicos , Suplementos Dietéticos/análisis , Humanos , Luteína/química , Permeabilidad , Solubilidad , Comprimidos/química
4.
J Biomol Struct Dyn ; 36(16): 4352-4365, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29241420

RESUMEN

Infections by Candida albicans in immune compromised patients cause significant morbidity and mortality. In the search for potential molecular targets for drug development, the family of agglutinin-like proteins (Als) in C. albicans have been identified due to numerous attributes associated with high virulence, most prominently due to their role in adherence. Here, molecular models of individual members of the Als family illustrated common and unique structure features. Additionally, dynamic simulations were performed to display regions of high mobility. The results showed variations between Als members in the fluctuation of the A1B1 protein loop, which is located at the entrance to the peptide binding cavity, suggesting that this feature may be a factor contributing to observed differences in affinities to ligands and adhesion properties. Molecular docking results further suggested that ligand affinity could be influenced by movements in the A1B1 loop. In addition, a new site was identified in Als in an area adjacent to the peptide binding cavity that could serve as a new binding site for the design of future anti-adhesion ligands that provide increased specificity inhibiting Als proteins from C. albicans.


Asunto(s)
Aglutininas/química , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candidiasis/prevención & control , Proteínas Fúngicas/química , Aglutininas/metabolismo , Antifúngicos/química , Antifúngicos/metabolismo , Sitios de Unión , Candida albicans/metabolismo , Candida albicans/patogenicidad , Candidiasis/microbiología , Proteínas Fúngicas/metabolismo , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Unión Proteica , Dominios Proteicos , Virulencia
5.
Nutr J ; 11: 26, 2012 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-22510447

RESUMEN

OBJECTIVE: The present study aimed to evaluate the influence of the relative composition of trace elements and vitamins in physicochemical stability of neonatal parenteral nutrition. MATERIAL AND METHODS: Three formulations for neonatal administration were selected; the main variable was the presence of trace elements and vitamins. The analyses where carried out immediately after preparation and at 24 h, 48 h, 72 h and 7 days after preparation. Three methods were selected to determine globule size: light obscuration, dynamic light scattering and optical microscopy. Complementary evaluation including visual inspection, determination of pH and osmolarity, peroxide levels and measurements of zeta potential were also performed. RESULTS: There was an observable alteration in color and phase separation in the PN stored at 25°C and 40°C. Neither globule size pattern, nor any other physicochemical characteristic evaluated appeared to be considerably altered in any of the analyzed formulations even after 7 days of storage at 5°C. Globule size in all the PN studied was consistent with the established limit, below 500 nm by DLS measurement, and PFAT5 was below 0.05% under all storage temperatures. CONCLUSION: Concomitant presence of trace elements and vitamins in the same neonatal formulation did not alter the evaluated aspects of stability.


Asunto(s)
Soluciones para Nutrición Parenteral/química , Oligoelementos/análisis , Vitaminas/análisis , Fenómenos Químicos , Química Farmacéutica/métodos , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Emulsiones Grasas Intravenosas/química , Humanos , Concentración de Iones de Hidrógeno , Concentración Osmolar , Soluciones para Nutrición Parenteral/farmacología , Nutrición Parenteral Total , Tamaño de la Partícula , Peróxidos/análisis , Oligoelementos/farmacología , Vitaminas/farmacología
6.
J Ethnopharmacol ; 135(1): 135-46, 2011 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-21396436

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Lower urinary tract symptoms (LUTS) are a common complaint among aging men and are usually caused by Benign Prostatic Hyperplasia (BPH). A number of medical treatments for LUTS/BPH exist, such as α-blockers, 5α-reductase inhibitors, phytotherapeutical drugs and combination therapies. Babassu is the common name of a Brazilian native palm tree called Orbignya speciosa, whose kernels are commonly used (eaten entirely or as a grounded powder), in parts of Brazil for the treatment of urinary disorders. This study investigates the effects of Orbignya speciosa nanoparticle extract, a newly developed phytotherapic formulation derived from the kernels of babassu, in the treatment of BPH. MATERIALS AND METHODS: Orbignya speciosa extract was obtained from the kernels, a nanoparticulate system was developed and acute toxicity test was performed. BPH primary stromal cell and tissue cultures were established and treated with 300µg/mL Orbignya speciosa nanoparticle (NanoOse) extract in order to evaluate its effects on apoptosis induction, cytotoxicity, cell morphology and proliferation. RESULTS: Our results indicated that NanoOSE shows no toxicity in animals and acts incisively by promoting morphological cell changes, reducing cell proliferation as well as inducing necrosis/apoptosis on BPH cells and tissues. CONCLUSIONS: This study provided the first report of the successful use of NanoOSE on BPH treatment which corroborates with the popular use of the kernels of this plant. The results also suggest the potential of NanoOSE as a candidate new phytotherapeutic agent on the management of BPH.


Asunto(s)
Arecaceae , Fitoterapia , Extractos Vegetales/uso terapéutico , Hiperplasia Prostática/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Brasil , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Femenino , Humanos , Masculino , Ratones , Nanotecnología , Necrosis , Extractos Vegetales/farmacología , Hiperplasia Prostática/fisiopatología , Semillas
7.
Artículo en Inglés | MEDLINE | ID: mdl-18955360

RESUMEN

Bacterial infections involving multidrug-resistant strains are one of the ten leading causes of death and an important health problem in need for new antibacterial sources and agents. Herein, we tested and compared four snake venoms (Agkistrodon rhodostoma, Bothrops jararaca, B. atrox and Lachesis muta) against 10 Gram-positive and Gram-negative drug-resistant clinical bacteria strains to identify them as new sources of potential antibacterial molecules. Our data revealed that, as efficient as some antibiotics currently on the market (minimal inhibitory concentration (MIC) = 1-32 µg mL(-1)), A. rhodostoma and B. atrox venoms were active against Staphylococcus epidermidis and Enterococcus faecalis (MIC = 4.5 µg mL(-1)), while B. jararaca inhibited S. aureus growth (MIC = 13 µg ml(-1)). As genomic and proteomic technologies are improving and developing rapidly, our results suggested that A. rhodostoma, B. atrox and B. jararaca venoms and glands are feasible sources for searching antimicrobial prototypes for future design new antibiotics against drug-resistant clinical bacteria. They also point to an additional perspective to fully identify the pharmacological potential of these venoms by using different techniques.

8.
Curr Microbiol ; 57(5): 463-8, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18810543

RESUMEN

Bacterial infections are a significant cause of morbidity and mortality among critically ill patients. The increase of antibiotic resistance in bacteria from human microbiota-such as Staphylococcus epidermidis, an important nosocomial pathogen that affects immunocompromised patients or those with indwelling devices-increased the desire for new antibiotics. In this study we designed, synthesized, and determined the antimicrobial activity of 27 thieno[2,3-b]pyridines (1, 2, 2a-2m, 3, 3a-3m) derivatives against a drug-resistant clinical S. epidermidis strain. In addition, we performed a structure-activity relationship analysis using a molecular modeling approach, and discuss the drug absorption, distribution, metabolism, excretion, and toxicity profile and Lipinski's "rule of five," which are tools to assess the relationship between structures and drug-like properties of active compounds. Our results showed that compound 3b (5-(1H-tetrazol-5-yl)-4-(3;-methylphenylamino)thieno[2,3-b]pyridine) was as active as oxacillin and chloramphenicol but with lower theoretical toxicity risks and a better drug likeness and drug score potential than chloramphenicol. All molecular modeling and biological results reinforced the promising profile of 3b for further experimental investigation and development of new antibacterial drugs.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Diseño de Fármacos , Farmacorresistencia Bacteriana , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus epidermidis/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/farmacocinética , Bacterias/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Humanos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Piridinas/síntesis química , Piridinas/química , Piridinas/farmacocinética , Piridinas/farmacología , Infecciones Estafilocócicas/microbiología , Relación Estructura-Actividad
9.
Bioorg Med Chem ; 16(1): 313-21, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-17937990

RESUMEN

Herpes Simplex Virus (HSV) infections are among the most common human diseases. In this work, we assess the structural features and electronic properties of a series of ten 1-hydroxyacridone derivatives (1a-j) recently described as a new class of non-nucleoside inhibitors of Herpes Simplex Virus-1 (HSV-1). Based on these molecules, we applied rigid analogue and isosteric replacement approaches to design and synthesize nine new 3H-benzo[b]pyrazolo[3,4-h]-1,6-naphthyridine derivatives (2a-i). The biological and computational results of these new molecules were compared with 1-hydroxyacridones. An inhibitory profile was observed in 10-Cl substituted 3H-benzo[b]pyrazolo[3,4-h]-1,6-naphthyridine derivative (2f), which presents the same substituent at the analogous position of 1-hydroxyacridone derivative (1b). The structure-activity relationship (SAR) studies pointed out the 10-position next to nitrogen atom as important for the anti-HSV-1 profile in the pyrazolo-naphthyridine derivatives tested, which reinforced the promising profile for further experimental investigation. The most potent acridone and pyrazolo-naphthridine derivatives were also submitted to an in silico ADMET screening in order to determine their overall drug-score, which confirmed their potential antiviral profile.


Asunto(s)
Acridinas/química , Antivirales/química , Herpesvirus Humano 1/efectos de los fármacos , Naftiridinas/química , Naftiridinas/farmacología , Acridinas/farmacología , Acridonas , Antivirales/farmacología , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Humanos , Relación Estructura-Actividad
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