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1.
Biomed Pharmacother ; 139: 111578, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33848774

RESUMEN

The COVID-19 has become of striking interest since the number of deaths is constantly rising all over the globe, and the search for an efficient treatment is more urgent. In light of this worrisome scenario, this opinion review aimed to discuss the current knowledge about the potential role of curcumin and its nanostructured systems on the SARS-CoV-2 targets. From this perspective, this work demonstrated that curcumin urges as a potential antiviral key for the treatment of SARS-CoV-2 based on its relation to the infection pathways. Moreover, the use of curcumin-loaded nanocarriers for increasing its bioavailability and therapeutic efficiency was highlighted. Additionally, the potential of the nanostructured systems by themselves and their synergic action with curcumin on molecular targets for viral infections have been explored. Finally, a viewpoint of the studies that need to be carried out to implant curcumin as a treatment for COVID-19 was addressed.


Asunto(s)
Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Curcumina/uso terapéutico , Sistemas de Liberación de Medicamentos , Nanomedicina , Animales , Ensayos Clínicos como Asunto , Humanos
2.
AAPS PharmSciTech ; 15(3): 612-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24510525

RESUMEN

The moderate heat treatment of amphotericin B (AmB) in its micellar form (M-AmB) results in superaggregates (H-AmB) that present a substantially lower toxicity and similar activity. The aim of this work was to evaluate the H-AmB behavior after a freeze-drying process. H-AmB and M-AmB micelles were evaluated before and after freeze-drying concerning their physicochemical and biological properties by spectrophotometry and activity/toxicity assay, respectively. Four concentrations of M-AmB and H-AmB were studied aiming to correlate their aggregation state and the respective biological behavior: 50 mg L(-1), 5 mg L(-1), 0.5 mg L(-1), and 0.05 mg L(-1). Then, potassium leakage and hemoglobin leakage from red blood cells were used to evaluate the acute and chronic toxicity, respectively. The efficacy of M-AmB and H-AmB formulations was assessed by potassium leakage from Candida albicans and by the broth microdilution method. After heating, in addition to an evident turbidity, a slight blueshift from 327 to 323 nm was also observed at the concentrations of 50 and 5 mg L(-1) for H-AmB. Additionally, an increase in the absorbance at 323 nm at the concentration of 0.5 mg L(-1) was detected. Concerning the toxicity, H-AmB caused significantly lower hemoglobin leakage than M-AmB. These results were observed for H-AmB before and after freeze-drying. However, there was no difference between H-AmB and M-AmB concerning their activity. Accordingly, the freeze-drying cycle did not show any influence on the behavior of heated formulations, highlighting the suitability of such a method to produce a new AmB product with a long shelf life and with both greater efficiency and less toxicity.


Asunto(s)
Anfotericina B/farmacología , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Liofilización , Calor , Tecnología Farmacéutica/métodos , Anfotericina B/química , Anfotericina B/toxicidad , Antifúngicos/química , Antifúngicos/toxicidad , Candida albicans/crecimiento & desarrollo , Candida albicans/metabolismo , Química Farmacéutica , Relación Dosis-Respuesta a Droga , Estabilidad de Medicamentos , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Hemoglobinas/metabolismo , Humanos , Micelas , Potasio/sangre , Espectrofotometría Ultravioleta , Factores de Tiempo
3.
Int J Pharm ; 454(2): 641-8, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23726904

RESUMEN

Amphotericin B (AmB) is a very efficient drug against serious diseases such as leishmaniasis and systemic fungal infections. However, its oral bioavailability is limited due to its poor solubility in water. Nevertheless, it is marketed as high-cost lipid parenteral formulations that may induce serious infusion-related side effects. In this study, oil-in-water (O/W) microemulsions (MEs) were developed and characterized with a view to their use as solubility enhancers and oral delivery systems for AmB. Therefore, different nonionic surfactants from the Tween(®) and Span(®) series were tested for their solubilization capacity in combination with several oils. Based on pseudoternary phase diagrams, AmB-loaded MEs with mean droplet sizes about 120 nm were successfully produced. They were able to improve the drug solubility up to 1000-fold. Rheological studies showed the MEs to be low-viscosity formulations with Newtonian behavior. Circular dichroism and absorption spectra revealed that part of the AmB in the MEs was aggregated as an AmB reservoir carrier. Cytotoxicity studies revealed limited toxicity to macrophage-like cells that may allow the formulations to be considered as suitable carriers for AmB.


Asunto(s)
Anfotericina B/química , Antiinfecciosos/química , Lípidos/química , Tensoactivos/química , Administración Oral , Anfotericina B/administración & dosificación , Animales , Antiinfecciosos/administración & dosificación , Línea Celular , Supervivencia Celular/efectos de los fármacos , Emulsiones , Ratones , Reología , Agua/química
4.
ScientificWorldJournal ; 9: 37-45, 2009 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-19151897

RESUMEN

The purpose of this study was to identify the knowledge and use of contraceptive methods by female adolescent students. The study was cross-sectional and quantitative, using a semi-structured questionnaire that was administered to 12- to 19-year-old female students in Maceió, Brazil. A representative and randomized sample was calculated, taking into account the number of hospital admissions for curettage. This study was approved by the Human Research Ethics Committee, and Epi Info software was used for data and result evaluation using the mean and chi-square statistical test. Our results show that the majority of students know of some contraceptive methods (95.5%), with the barrier/hormonal methods being the most mentioned (72.4%). Abortion and aborting drugs were inaccurately described as contraceptives, and 37.9% of the sexually active girls did not make use of any method. The barrier methods were the most used (35.85%). A significant association was found in the total sample (2,592) between pregnancy and the use of any contraceptive method. This association was not found, however, in the group having an active sexual life (559). The study points to a knowledge of contraceptive methods, especially by teenagers who have already been pregnant, but contraceptives were not adequately used. The low use of chemical methods of contraception brings the risk of pregnancy. Since abortion and aborting drugs were incorrectly cited as contraceptive methods, this implies a nonpreventive attitude towards pregnancy.


Asunto(s)
Conducta Anticonceptiva/estadística & datos numéricos , Anticonceptivos/administración & dosificación , Conocimientos, Actitudes y Práctica en Salud , Conducta Sexual/estadística & datos numéricos , Adolescente , Brasil/epidemiología , Niño , Femenino , Humanos , Embarazo , Adulto Joven
5.
Drug Dev Ind Pharm ; 34(10): 1111-6, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18777238

RESUMEN

Aqueous suspensions containing magnetic microparticles have been increasingly used in biosciences and biotechnology. This work describes an experimental procedure to produce superparamagnetic microparticles. The particles were prepared based on the coprecipitation of iron salts in alkaline medium. Afterwards, characterization was performed. Characterization data demonstrated that magnetite was the dominant phase in the analyzed sample, and 50% of them were in the size range of 0.5-5 microm. The results suggest that the experimental protocol provided a simple synthesis route to produce superparamagnetic microparticles. Such properties may be very useful for biotechnological purposes.


Asunto(s)
Biotecnología/métodos , Óxido Ferrosoférrico/química , Magnetismo , Tamaño de la Partícula , Difracción de Rayos X
6.
Int J Pharm ; 344(1-2): 158-60, 2007 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-17614224

RESUMEN

The aim of this work was to investigate the influence of a lipophilic drug, Ibuprofen, on the stability of o/w emulsions. Five formulations were prepared by the phase inversion temperature (PIT) method, and Ibuprofen was incorporated into their oil phase. Emulsion stability was evaluated by short- and long-term studies. Concerning the former, stability under centrifugation showed an improved profile for Ibuprofen-loaded emulsions. The latter confirmed such findings. In conclusion, a rather resistant interfacial film may take place when Ibuprofen was incorporated into the emulsions. Therefore, the critical hydrophilic-lipophilic-balance (HLB) of o/w emulsions can be affected by a lipophilic drug into their oil phase. Such approach is of great importance on the development of lipid carriers for therapeutic drug targeting.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Portadores de Fármacos/química , Emulsiones/química , Ibuprofeno/química , Antiinflamatorios no Esteroideos/administración & dosificación , Estabilidad de Medicamentos , Emulsionantes/química , Concentración de Iones de Hidrógeno , Ibuprofeno/administración & dosificación , Aceite Mineral/química , Reología , Agua/química
7.
Int J Pharm ; 334(1-2): 42-7, 2007 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-17113734

RESUMEN

This work evaluates an experimental set-up to coat superparamagnetic particles in order to protect them from gastric dissolution. First, magnetic particles were produced by coprecipitation of iron salts in alkaline medium. Afterwards, an emulsification/cross-linking reaction was carried out in order to produce magnetic polymeric particles. The sample characterization was performed by X-ray powder diffraction, laser scattering particle size analysis, optical microscopy, thermogravimetric analysis and vibrating sample magnetometry. In vitro dissolution tests at gastric pH were evaluated for both magnetic particles and magnetic polymeric particles. The characterization data have demonstrated the feasibility of the presented method to coat, and protect magnetite particles from gastric dissolution. Such systems may be very promising for oral administration.


Asunto(s)
Óxido Ferrosoférrico/química , Magnetismo , Polímeros/química , Xilanos/química , Administración Oral , Preparaciones de Acción Retardada , Sistemas de Liberación de Medicamentos , Óxido Ferrosoférrico/síntesis química , Concentración de Iones de Hidrógeno , Rayos Láser , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Dispersión de Radiación , Solubilidad , Termogravimetría , Difracción de Rayos X , Zea mays
8.
Radiat Environ Biophys ; 45(4): 245-52, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17021785

RESUMEN

The recent development of superconducting magnets has resulted in a huge increase in human exposure to very large static magnetic fields of up to several teslas (T). Considering the rapid advances in applications and the great increases in the strength of magnetic fields used, especially in magnetic resonance imaging, safety concerns about magnetic field exposure have become a key issue. This paper points out some of these safety concerns and gives an overview of the findings about this theme, focusing mainly on mechanisms of magnetic field interaction with living organisms and the consequent effects.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Seguridad , Factores de Edad , Síntomas Conductuales/etiología , Circulación Sanguínea/fisiología , Líquidos Corporales/fisiología , Humanos , Presión
9.
AAPS PharmSciTech ; 7(1): E21, 2006 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-16584152

RESUMEN

The aim of this work was to develop a methodology for rapid determination of the critical hydrophilic-lipophilic balance (HLB) value of lipophilic fractions of emulsions. The emulsions were prepared by the spontaneous emulsification process with HLB value from 4.3 to 16.7. The preparations were stored at 2 different temperatures (25 degrees C and 4 degrees C) and their physicochemical behavior was evaluated by the micro-emultocrit technique and the long-term stability study. The experimental data show a reverse relationship between HLB values of the surfactant mixtures and emulsion stability. A close correlation between the results for both stability procedures was observed, suggesting the use of micro-emultocrit to predict stabilities of such systems. In addition, it was found that the critical HLB of the Mygliol 812 was 15.367.


Asunto(s)
Emulsiones , Tecnología Farmacéutica , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Solubilidad
10.
AAPS PharmSciTech ; 7(1): E146-E152, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28290036

RESUMEN

The aim of this work was to develop a methodology for rapid determination of the critical hydrophilic-lipophilic balance (HLB) value of lipophilic fractions of emulsions. The emulsions were prepared by the spontaneous emulsification process with HLB value from 4.3 to 16.7. The preparations were stored at 2 different temperatures (25°C and 4°C) and their physicochemical behavior was evaluated by the micro-emultocrit technique and the long-term stability study. The experimental data show a reverse relationship between HLB values of the surfactant mixtures and emulsion stability. A close correlation between the results for both stability procedures was observed, suggesting the use of micro-emultocrit to predict stabilities of such systems. In addition, it was found that the critical HLB of the Mygliol 812 was 15.367.

11.
Acta Cir Bras ; 20 Suppl 1: 257-61, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16186987

RESUMEN

PURPOSE: Amphotericin B (AmB), an antifungal agent that presents a broad spectrum of activity, remains the gold standard in the antifungal therapy. However, sometimes the high level of toxicity forbids its clinical use. The aim of this work was to evaluate and compare the efficacy and toxicity in vitro of Fungizon (AmB-D) and two new different AmB formulations. METHODS: three products were studied: Fungizon, and two Fungizon /Lipofundin admixtures, which were diluted through two methods: in the first one, Fungizon was previously diluted with water for injection and then, in Lipofundin (AmB-DAL); the second method consisted of a primary dilution of AmB-D as a powder in the referred emulsion (AmB-DL). For the in vitro assay, two cell models were used: Red Blood Cells (RBC) from human donors and Candida tropicallis (Ct). The in vitro evaluation (K+ leakage, hemoglobin leakage and cell survival rate-CSR) was performed at four AmB concentrations (from 50 to 0.05 mg x L(-1)). RESULTS: The results showed that the action of AmB was not only concentration dependent, but also cellular type and vehicle kind dependent. At AmB concentrations of 50 mg x L(-1), although the hemoglobin leakage for AmB-D was almost complete (99.51), for AmB-DAL and AmB-DL this value tended to zero. The p = 0.000 showed that AmB-D was significantly more hemolytic. CONCLUSION: The Fungizon-Lipofundin admixtures seem to be the more valuable AmB carrier systems due to their best therapeutic index presented.


Asunto(s)
Anfotericina B/farmacología , Antifúngicos/farmacología , Nutrición Parenteral/normas , Fosfolípidos/farmacología , Sorbitol/farmacología , Anfotericina B/efectos adversos , Análisis de Varianza , Antifúngicos/efectos adversos , Candida tropicalis/efectos de los fármacos , Portadores de Fármacos , Combinación de Medicamentos , Eritrocitos/efectos de los fármacos , Femenino , Hemoglobinas/efectos de los fármacos , Humanos , Técnicas In Vitro , Modelos Biológicos , Fosfolípidos/efectos adversos , Potasio/sangre , Sorbitol/efectos adversos , Resultado del Tratamiento
12.
Acta cir. bras ; Acta cir. bras;20(supl.1): 257-261, 2005.
Artículo en Inglés | LILACS | ID: lil-414652

RESUMEN

OBJETIVO: A anfotericina B é um agente antifúngico de largo espectro bastante empregado na terapia antifúngica. Entretanto, esta molécula apresenta um alto nível de toxicidade que, na maioria das vezes, impede o seu uso contínuo na terapêutica médica. O objetivo deste artigo foi comparar a eficácia e a toxicidade in vitro do Fungizon™ (AmB-D) e de dois sistemas carreadores de AmB. MÉTODOS: Três produtos foram avaliados: o Fungizon™ , e dois sistemas oriundos da mistura entre o Fungizon™ e o Lipofundin™ , uma emulsão de uso parenteral. Tais sistemas foram obtidos por duas técnicas: Na primeira diluiu-se previamanete o Fungizon™ com água para injetáveis e em seguida inseriu-se o Lipofundin™ (AmB-DAL); o segundo método consistiu na diluíção extemporânea do Fungizon™ com a referida emulsão (AmB-DL). Dois modelos celulares foram empregados no estudo: os eritrócitos (RBC) oriundos de doadores humanos e a Candida tropicalis (Ct). A avaliação in vitro (liberação de K+ e hemoglobina, e o índice de sobrevivência celular-CSR) foi realizado com quatro concentrações de AmB (entre 50 e 0.05mg.L-1). RESULTADOS: Os resultados demonstram que a ação da AmB não só foi dependente da concentração como também variou de acordo com o modelo celular e o veículo que diluiu o Fungizon™ . Nas concentrações de 50 mg.L-1, apesar da liberação de hemoglobina ser quase que total para AmB-D (99.51), para a AmB-DAL e AmB-DL este valor tendeu a zero. Um p = 0.000 demonstrou que AmB-D foi significativamente mais hemolítico. CONCLUSÃO: A mistura Fungizon™ -Lipofundin™ aparenta ser um bom sistema para carrear a AmB tendo em vista seu elevado índice terapêutico demonstrado.


Asunto(s)
Femenino , Humanos , Anfotericina B/farmacología , Antifúngicos/farmacología , Técnicas In Vitro , Nutrición Parenteral/normas , Fosfolípidos/farmacología , Sorbitol/farmacología , Análisis de Varianza , Anfotericina B/efectos adversos , Antifúngicos/efectos adversos , Candida tropicalis/efectos de los fármacos , Portadores de Fármacos , Combinación de Medicamentos , Eritrocitos/efectos de los fármacos , Hemoglobinas/efectos de los fármacos , Modelos Biológicos , Fosfolípidos/efectos adversos , Potasio/sangre , Sorbitol/efectos adversos , Resultado del Tratamiento
13.
J Pharm Sci ; 93(6): 1557-65, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15124213

RESUMEN

This work analyzes the genotoxicity potential, in the G2 phase of the cellular cycle, of an amphotericin B (AmB) commercially available form (Fungizone), and correlates it with the physicochemical properties of this product in aqueous media. The genotoxic studies were performed using peripheral blood lymphocytes from human donors. The chromosome aberrations and mitotic index were determined. Absorption spectra of Fungizone were obtained by dispersion of the stock solution in water for injection at various AmB concentrations, and using different cuvette path lengths for spectrophotometric determination. The absorption spectra of Fungizone in water are concentration dependent. High concentrations of Fungizone present a spectrum with an intense band at 340 nm, characteristic of AmB self-association. Conversely, at low concentrations, the spectra are similar to those obtained with AmB in methanol, with a positive band at 409 nm, assigned to AmB monomeric form. Similarly, the cytogenetic analysis shows an important decrease on the mitotic index, which is also concentration dependent when compared with control. Furthermore, the chromosome aberrations present a small, not statistically significant, increase only at the highest concentration. The results suggest that the Fungizone presents a cytotoxicity similar to membrane pore formation in mammalian cells that depends on the existence of self-associated AmB. In the presence of only monomeric forms, this phenomenon disappears. However, no genotoxicity was observed in this study.


Asunto(s)
Anfotericina B/toxicidad , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/fisiología , Adulto , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Humanos , Pruebas de Mutagenicidad/métodos
14.
J Pharm Sci ; 91(11): 2354-66, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12379920

RESUMEN

Mixing Fungizone with a fat emulsion used for nutritional purpose (Intralipid or Lipofundin ) was reported to decrease Amphotericin B (AmB) toxicity in clinical use. In an effort to understand the reason for this phenomenon, spectral and morphological analyses were done for the Fungizone and Fungizone /Lipofundin admixture (FLmix). The absorption spectra analyses showed that not only Fungizone but also FLmix presented spectra that were concentration dependent. Moreover, the spectra of FLmix remained stable until the concentration of 5 x 10(-7) M, and only at 5 x 10(-8) M did they become similar in shape to the Fungizone spectra. Morphological studies revealed that even though emulsion droplets with or without Fungizone presented the same particle size, the former was less electron dense compared with Lipofundin alone. These results suggest a kind of association between Fungizoneand Lipofundin that remains over the whole range of concentrations. This hypothesis was confirmed by in vitro studies in which FLmix presented an important selectivity against human and fungal cells compared with Fungizone. These findings suggest that parenteral emulsions should be able to reduce the AmB toxicity probably by changing the AmB self-association state by binding it with emulsion droplets.


Asunto(s)
Anfotericina B/farmacocinética , Anfotericina B/toxicidad , Anfotericina B/química , Candida tropicalis/efectos de los fármacos , Química Farmacéutica , Interacciones Farmacológicas/fisiología , Emulsiones , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Femenino , Humanos
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