Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
Int J Pharm ; 350(1-2): 155-65, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-17933475

RESUMO

The geometry, frequency and intensity of the vibrational bands of miconazole were derived from the density functional theory (DFT) calculations with the hybrid functional B3LYP and the 6-31G(d) basis set. Starting from the fully AM1 optimized geometries of miconazole/betaCD/acids complexes, the miconazole/acid dimers were reoptimized at the B3LYP/6-31G(d) level. Three acids were studied: maleic, fumaric and l-tartaric acids. To begin with the vibrational spectral data obtained from solid phase in mid FT-IR spectrum of miconazole and its dimers are assigned based on the results of the normal modes calculations. All the observed spectra and the calculated ones are found to be in good agreement. In a second step, theoretical results allowed the assignment of FT-IR spectrum for the miconazole/HPgammaCD inclusion complex produced by supercritical carbon dioxide treatment and confirmed the inclusion of miconazole. The experimental spectra for the miconazole/HPgammaCD/acids complexes prepared by supercritical carbon dioxide processing were also assigned using theoretical results. The results confirmed the presence of a genuine inclusion complex and also the interaction between miconazole and the acid.


Assuntos
Ciclodextrinas/química , Miconazol/química , Dimerização , Fumaratos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tartaratos/química , Vibração
2.
Int J Pharm ; 347(1-2): 62-70, 2008 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-17681684

RESUMO

(1)H NMR spectrometry, FT-IR spectroscopy, as well as molecular modeling at the AM1 level and normal mode analysis were used to characterise the interactions and the formation of inclusion complexes between three organic acids: maleic, fumaric, L-tartaric acids and betaCD. In aqueous medium, the complexation was confirmed by (1)H NMR spectroscopy using two-dimensional technique. The stable geometries of the complexes were determined by molecular modeling. Experimental infrared frequencies were assigned on the base of the vibrational normal mode calculation at the fully optimized geometry for the inclusion complexes. All the results point out the presence of stable inclusion complexes between acids and betaCD at the solid state. These results show the double role of the acid. Correlated with the theoretical and experimental data previously obtained for the miconazole/CD/acids complexes, in function of both acids and CDs structures, the acids can either stabilize the complexes by formation of a multicomponent complex or form acid/CD inclusion complexes, hindering the guest inclusion.


Assuntos
Ácidos Dicarboxílicos/química , Miconazol/química , Modelos Moleculares , beta-Ciclodextrinas/química , Fumaratos/química , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Maleatos/química , Veículos Farmacêuticos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tartaratos/química , Termodinâmica
3.
Gynecol Obstet Invest ; 66(2): 84-90, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18434742

RESUMO

BACKGROUND/AIMS: The aim of this study was to induce endometriosis in female rhesus macaques (Macaca mulatta) for research purposes. METHODS: Three female monkeys from 4 to 4.5 years of age underwent three consecutive attempts at endometriosis induction over an 8-month period: (i) the first attempt involved intravaginal sampling of endometrial tissue and transplantation into the intrapelvic cavity; (ii) the second entailed surgical removal of endometrium after hysterotomy and intra-abdominal placement, and (iii) the third used endometrial mucosa obtained by scraping the uterus after hysterectomy, placed in a surgical pouch created in the retrovesical space (Retzius). In each case, the pelvic cavity was closely inspected after 7, 9, and 6 weeks respectively for the presence of endometriotic lesions, and peritoneal biopsies were performed. RESULTS: Neither macroscopic observation nor histological analysis revealed any endometriotic lesions. CONCLUSION: This failure to induce endometriosis in female rhesus macaques suggests that this species is not the most efficient experimental model among primates to investigate endometriosis development or treatment.


Assuntos
Modelos Animais de Doenças , Endometriose/patologia , Macaca mulatta , Doenças dos Macacos/patologia , Animais , Biópsia/veterinária , Endometriose/cirurgia , Feminino , Histocitoquímica/veterinária , Doenças dos Macacos/cirurgia
4.
Eur J Pharm Biopharm ; 66(3): 483-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17407809

RESUMO

Solid lipid microparticles (SLMs) loaded with the sunscreen agent, octyl-dimethylaminobenzoate (ODAB), were prepared in order to achieve enhanced sunscreen photostability. The microparticles were produced by the melt dispersion technique using glyceryl behenate as lipidic material and poloxamer 188 as the emulsifier. The obtained SLMs showed proper features in terms of morphology, size distribution (1.67-15.81 microm) and ODAB loading (16.15+/-0.11%, w/w). The sunscreen release from the SLMs was slower than its dissolution rate and the photodecomposition of ODAB was markedly decreased (>51.3%) by encapsulation into the lipid microparticles. The efficacy of the SLM carrier system was also evaluated after their introduction in model topical formulations (i.e., hydrogel and oil-in-water emulsion). Further in vitro release measurements, performed using Franz diffusion cells with polycarbonate membranes, indicated that the retention capacity of the microparticles was lost after their incorporation into the emulsion, whereas it was retained in the hydrogel. Moreover, the SLMs achieved a reduction of the sunscreen photodegradation in the hydrogel vehicle (the ODAB loss decreased from 87.4% to 59.1%), whereas no significant photoprotective effect was observed in the emulsion. Therefore, the efficacy of the ODAB-loaded SLMs was markedly affected by the vehicle.


Assuntos
Ácidos Graxos/administração & dosagem , Poloxâmero/administração & dosagem , Protetores Solares/administração & dosagem , p-Dimetilaminoazobenzeno/análogos & derivados , Estabilidade de Medicamentos , Veículos Farmacêuticos , Fotólise , Protetores Solares/química , p-Dimetilaminoazobenzeno/administração & dosagem , p-Dimetilaminoazobenzeno/química
5.
Eur J Pharm Biopharm ; 65(1): 47-56, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16962749

RESUMO

The controlled release of drugs for pulmonary delivery is a research field which has been so far rather unexploited but is currently becoming increasingly attractive. The introduction part of this research article first details the potential advantages of solid lipid microparticles (SLMs) as drug carrier compared to liposomes and polymeric microspheres. The aim of this work is to use SLMs to impart a sustained release profile to a model drug, salbutamol acetonide (SA). SA was synthesized from salbutamol in order to increase the lipophilicity of this molecule and thereby to increase its incorporation efficiency into SLMs. SA-loaded SLMs were then produced by a hot emulsion technique followed by high-shear homogenisation and the manufacturing parameters were optimized using the experimental design methodology in order to reach a suitable particle size for pulmonary administration. Scanning electron micrographs showed that SLMs are spherical, have a smooth surface and that SA crystallizes outside of the particles when the drug loading is higher than 20%. This was confirmed by X-ray diffraction. SA in vitro release study from SLMs showed that the release rate increased with SA loading but remained in every case lower than the dissolution rate of pure SA.


Assuntos
Preparações de Ação Retardada , Portadores de Fármacos , Lipídeos/química , Sistema Respiratório/metabolismo , Administração por Inalação , Albuterol/administração & dosagem , Albuterol/análogos & derivados , Albuterol/química , Albuterol/metabolismo , Broncodilatadores/administração & dosagem , Broncodilatadores/química , Broncodilatadores/metabolismo , Varredura Diferencial de Calorimetria , Química Farmacêutica , Cristalografia por Raios X , Composição de Medicamentos , Humanos , Cinética , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Solubilidade , Tecnologia Farmacêutica/métodos
6.
Int J Pharm ; 342(1-2): 152-60, 2007 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-17573213

RESUMO

The inclusion of miconazole into cyclodextrin cavity has been demonstrated by different authors. Preliminary studies have shown which fragment of the molecule is involved in the inclusion. In the present study, AM1 approximate molecular orbital calculations have been performed on several cyclodextrins complexes (betaCD, HPbetaCD and HPgammaCD) with miconazole and acidic compounds (maleic, fumaric and L-tartaric acids) as partners. For all the binary complexes, the inclusion of the dichlorobenzene-CH(2)-O-group leads to the most stable complex. For the ternary complexes, depending on their conformation and/or their structures, the acids can either stabilize or destabilize the complex. All the theoretical results were in good agreement with experimental data of miconazole inclusion yields into cyclodextrins. This work clearly demonstrates that the structure of both cyclodextrin and acid plays a key-role in the formation of inclusion complexes.


Assuntos
Antifúngicos/química , Ciclodextrinas/química , Miconazol/química , Cromatografia com Fluido Supercrítico , Simulação por Computador , Modelos Moleculares , Modelos Estatísticos , Conformação Molecular , Relação Estrutura-Atividade
7.
Eur J Pharm Sci ; 28(3): 189-95, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16520026

RESUMO

Ro 28-2653 (5-biphenyl-4-yl-5-[4-(4-nitro-phenyl)-piperazin-1-yl]-pyrimidine-2,4,6-trione) is a new synthetic inhibitor of matrix metalloproteinases (MMPs) with a high selectivity towards MMP2, MMP9 and membrane type 1-MMP. It has been shown that cyclodextrins (CDs) are able to form inclusion complexes with Ro 28-2653 and to increase its aqueous solubility. The aim of this study is to demonstrate that an increase in Ro 28-2653 solubility, via ternary complex formation, can lead to an increase in the oral bioavailability of this drug. This study shows that a synergistic effect exists between hydroxypropyl-beta-cyclodextrin (HP-beta-CD) and l-lysine. The use of this multicomponent system enabled the preparation of oral and intravenous solutions of Ro 28-2653. In vivo evaluation of the oral solution of the inclusion complex of Ro 28-2653 in comparison with a suspension of the same uncomplexed drug showed a significant (p<0.05) increase in absolute bioavailability. The area under curve (AUC) and the peak serum concentration (Cmax) were approximately 10 times higher than those obtained with the suspension, while the time (Tmax) to reach Cmax was reduced. Moreover, in vivo administration of Ro 28-2653 solutions highlighted some information about the pharmacokinetic behavior of Ro 28-2653: a long biologic half-life (about 15.5h) and a small overall volume of distribution (8l).


Assuntos
Excipientes/química , Lisina/química , Inibidores de Metaloproteinases de Matriz , Piperazinas/farmacocinética , Inibidores de Proteases/farmacocinética , Pirimidinas/farmacocinética , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Administração Oral , Animais , Disponibilidade Biológica , Química Farmacêutica , Injeções Intravenosas , Piperazinas/administração & dosagem , Piperazinas/química , Inibidores de Proteases/administração & dosagem , Inibidores de Proteases/química , Pirimidinas/administração & dosagem , Pirimidinas/química , Ovinos , Solubilidade , Soluções , Suspensões
8.
Int J Pharm ; 312(1-2): 75-82, 2006 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-16455215

RESUMO

Lipophilic drugs have limited solubility in phospholipid systems, hence maximum entrapment levels in liposomes are known to be low. "Drugs-in-cyclodextrin-in-liposome" systems were previously proposed to overcome this drawback but studies were limited to betaCD and HPbetaCD. In some cases, other cyclodextrins may be more interesting than betaCD or HPbetaCD, such as methylated cyclodextrins. However, these cyclodextrins are known to extract lipid components from the lipid membrane, which may destabilize liposomes. We tested the influence of several cyclodextrins (betaCD, gammaCD, Dimeb, Trimeb, Crysmeb, Rameb, HPbetaCD and HPgammaCD) on the aqueous solubility of betamethasone by phase solubility diagrams and on the encapsulation efficiency in liposomes. The release kinetics of betamethasone was studied using Franz diffusion cells. We showed that release kinetics are directly correlated with encapsulation efficiency, which is closely related to betamethasone concentration in cyclodextrin complex solution. No liposome destruction was observed, even with the testing of methylated cyclodextrins at the highest concentration (40 mM). This can be explained by the fact that these cyclodextrins have a higher affinity for betamethasone than for cholesterol. This was proved by the comparison of phase solubility diagrams of both betamethasone and cholesterol.


Assuntos
Betametasona/química , Ciclodextrinas/química , Aminas/química , Química Farmacêutica , Colesterol/química , Técnica de Fratura por Congelamento , Géis , Cinética , Lipossomos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Fosfatidilcolinas/química , Solubilidade , Água
9.
J Feline Med Surg ; 8(1): 45-54, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16213765

RESUMO

This study investigated the effect of inhaled fluticasone on lower airway inflammation and bronchial responsiveness (BR) to inhaled carbachol in cats with very mild, chronic bronchitis (n = 5) that were compared with healthy cats serving as controls (n = 6). Chest radiographs, BR tests performed non-invasively by barometric whole body plethysmography (BWBP) and bronchoalveolar lavage (BAL) were performed before and after treatment. BR was quantified by calculating the concentration of carbachol inducing bronchoconstriction (C-Penh300%), defined as a 300% increase of baseline Penh, an index of bronchoconstriction obtained by BWBP. BAL fluid was analyzed cytologically and the oxidant marker 8-iso-PGF2alpha was determined. At test 1, healthy cats and cats with bronchitis were untreated, whereas for test 2 inhalant fluticasone (250 microg once daily) was administrated for 2 consecutive weeks to cats with bronchitis. Control cats remained untreated. Inhaled fluticasone induced a significant increase in C-Penh300% and a significant decrease of BAL fluid total cells, macrophages, neutrophils and 8-iso-PGF2alpha in cats with bronchitis, whilst untreated control cats did not show significant changes over time. This study shows that a 2-week fluticasone treatment significantly reduced lower airway inflammation in very mild bronchitis. BR could be successfully monitored in cats using BWPB and decreased significantly in response to inhaled fluticasone. 8-Iso-PGF2alpha in BAL fluid was responsive to treatment and appeared as a sensitive biomarker of lower airway inflammation in cats.


Assuntos
Androstadienos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Bronquite Crônica/veterinária , Broncodilatadores/administração & dosagem , Doenças do Gato/tratamento farmacológico , Administração por Inalação , Animais , Bronquite Crônica/tratamento farmacológico , Líquido da Lavagem Broncoalveolar/química , Estudos de Casos e Controles , Gatos , Feminino , Fluticasona , Masculino , Pletismografia/veterinária , Resultado do Tratamento
10.
Expert Opin Drug Deliv ; 2(1): 75-87, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16296736

RESUMO

This review details the properties of solid lipid microparticles (SLMs): a promising drug carrier system that has been until now rather unexploited. First, the advantages of SLMs compared with other drug carrier systems are listed. Then an overview of SLM manufacturing compounds and techniques is presented. A detailed discussion of the characteristics of SLMs follows, and includes the determination of particle size distribution, the determination of SLM morphology, the solid-state analysis, the determination of SLM drug loading and the factors influencing it. The in vitro drug release studies that have been carried out so far and the parameters affecting them are also described. Some preliminary in vivo aspects (in vivo drug release studies, biocompatibility studies and in vivo fate) are also considered.


Assuntos
Portadores de Fármacos , Lipídeos/química , Microesferas , Preparações Farmacêuticas/administração & dosagem , Animais , Química Farmacêutica , Preparações de Ação Retardada , Vias de Administração de Medicamentos , Excipientes/química , Humanos , Tamanho da Partícula , Preparações Farmacêuticas/química , Solubilidade , Propriedades de Superfície , Fatores de Tempo
11.
J Pharm Pharm Sci ; 8(2): 163-74, 2005 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-16124927

RESUMO

PURPOSE: Ro 28-2653 (RO) is a synthetic inhibitor of matrix metalloproteinases (MMPs), which is potentially effective against bronchial remodeling. Given that this molecule has very poor aqueous solubility, different cyclodextrins (CDs) have been tested to increase its solubility. The aim of this study was to prepare and to characterize inclusion complexes between RO and CDs, in order to develop nebulizable solutions. METHODS: The complex formation was investigated by phase solubility studies. (1)H-NMR spectroscopy and molecular modeling studies were carried out to elucidate the structure of the inclusion complex between RO and dimethyl-beta-CD (DIMEB). Nebulizable solutions of RO were developed with CDs and a stability study was performed over 9 months. RESULTS: The phase solubility studies showed that beta-CD and its derivatives form a 1:2 complex with RO, whereas gamma-CD includes RO with a 1:1 stoichiometry and a weak stability constant. T-ROESY spectra showed that DIMEB is able to complex two RO substituents (nitrophenyl and biphenyl groups) with preferential orientations, while molecular modeling demonstrated that the configurations observed with (1)H-NMR are energetically favorable, especially owing to H-bond formation between RO and DIMEB. Two CDs were selected to develop nebulizable solutions of RO and the stability study demonstrated that RO degradation in solution is strongly dependent on the concentration of the 1:2 inclusion complex. CONCLUSIONS: CDs are able to include RO and to improve its aqueous solubility. The beta-CD derivatives can be used to formulate nebulizable solutions of RO, the stability of which depends on the concentration of the 1:2 complex.


Assuntos
Ciclodextrinas/química , Espectroscopia de Ressonância Magnética/métodos , Inibidores de Metaloproteinases de Matriz , Modelos Moleculares , Piperazinas/química , Pirimidinas/química , Ciclodextrinas/análise , Estabilidade de Medicamentos , Nebulizadores e Vaporizadores , Soluções Farmacêuticas/análise , Soluções Farmacêuticas/química , Piperazinas/análise , Inibidores de Proteases/análise , Inibidores de Proteases/química , Prótons , Pirimidinas/análise , Solubilidade/efeitos dos fármacos , Água/química
12.
Mini Rev Med Chem ; 4(6): 659-68, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15279600

RESUMO

Increasing interest in the role of omega3 fatty acids has arisen in these latest years since evidence of their implication in the cardioprotective fish based diet of the Inuit has been demonstrated. Furthermore, several in vitro, in vivo and epidemiological studies support the benefit of this fatty acids intake in various pathological states such as in the cardiovascular, cancer, inflammation, psychiatric, paediatric, pulmonary, dermatological and ophthalmologic fields. This review will focus on metabolism and pharmacological implication of omega3 fatty acids intake as well as its interest in the prevention or treatment of the above-mentioned pathologies.


Assuntos
Ácido Araquidônico/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-3/farmacologia , Ácido Araquidônico/química , Doenças Cardiovasculares/prevenção & controle , Eicosanoides/biossíntese , Oftalmopatias/prevenção & controle , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/uso terapêutico , Feminino , Humanos , Inflamação/prevenção & controle , Lipoxigenase/metabolismo , Pneumopatias/prevenção & controle , Doenças do Sistema Nervoso/prevenção & controle , Gravidez , Prostaglandina-Endoperóxido Sintases/metabolismo , Transdução de Sinais , Dermatopatias/prevenção & controle
13.
J Pharm Pharm Sci ; 7(3): 378-88, 2004 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-15576020

RESUMO

PURPOSE: The aim of the study is to evaluate the effect of different acidic compounds on the inclusion of miconazole (MICO) in several cyclodextrins (CDs) using supercritical carbon dioxide (SCCO(2) ) processing. METHODS: Physical mixtures were processed by SCCO(2) at 30 MPa, 125 degrees C during 60 minutes in a static mode to produce inclusion complexes. The inclusion complexes were characterized by differential solubility, Fourier transform infrared spectroscopy (FT-IR) and dissolution test. RESULTS: The best inclusion yields were achieved with the combination of MICO base and HPgammaCD with or without acids. Maleic and fumaric acids influenced the MICO inclusion differently in function of their conformation. During the process, a miconazole salt was observed with maleic acid and characterized by thermal analysis and mass spectrometry. The kinetics inclusion followed a saturation-type shape curve. FT-IR confirmed the presence of genuine inclusion complexes. The complexes MICO base/HPgammaCD/(L-tartaric acid) enhanced the dissolution rates of MICO more than the corresponding physical mixtures did. Lastly, the stability study revealed that the complexes were stable. CONCLUSIONS: The formation of stable complexes between MICO and CDs is possible using SCCO(2). Moreover an acidic ternary compound is able to modify the formation of the complex. The inclusion complexes, which show better dissolution profiles than those with the corresponding physical mixtures, could lead to an increase of the oral bioavailability of MICO.


Assuntos
Dióxido de Carbono/química , Química Farmacêutica , Ciclodextrinas/química , Miconazol/química , Concentração de Íons de Hidrogênio
14.
Eur J Pharm Sci ; 15(4): 347-53, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11988396

RESUMO

Few analytical techniques allow to evaluate the inclusion yield of cyclodextrin-drug complexes, because most manufacturing processes give amorphous products. In this study, we have developed an alternative method to differential scanning calorimetry, to accurately determine the free/complexed piroxicam ratio by UV spectroscopy. This method is based on the differential solubility of the piroxicam-beta-cyclodextrin 1:2.5 mol/mol complex in water-acetonitrile (1:1, v/v) (Solvent A) or in anhydrous acetonitrile (Solvent B), both containing 0.05 M HCl. In anhydrous acetonitrile, beta-cyclodextrin is insoluble and the included drug remains entrapped, allowing the free piroxicam determination, while with 50% of water, the complex is totally dissolved, allowing the determination of the total guest content. This method was validated for linearity, precision and accuracy. The presence of cyclodextrin does not influence the assays, but more than 0.5% of water in Solvent B significantly affects the determination of the free piroxicam content. In comparison with differential scanning calorimetry, both detectability and precision were improved. It is now possible to analyse complexes with an inclusion purity greater than 99%.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Piroxicam/análise , Varredura Diferencial de Calorimetria , Ciclodextrinas/química , Reprodutibilidade dos Testes , Solubilidade , Espectrofotometria Ultravioleta
15.
J Pharm Biomed Anal ; 36(1): 133-43, 2004 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-15351057

RESUMO

In the framework of a preliminary study on the transdermal penetration of cyproterone acetate (CPA), a simple and rapid procedure involving an extraction step coupled to a HPLC-UV determination has been developed for the separation and quantification of CPA in the two main skin layers-epidermis and dermis-after local application. The separation of epidermis and dermis layers was carefully carried out by means of a sharp spatula after skin immersion in heated water at 65 degrees C. The two skin layers were then treated separately according to the same process: (1) sample homogenization by vibration after freezing with liquid nitrogen in a Mikro-Dismembrator; (2) CPA extraction with methanol after addition of the internal standard (betamethasone dipropionate); (3) centrifugation; (4) evaporation of a supernatant aliquot; (5) dissolution of the dry residue in methanol and addition of water; (6) centrifugation; (7) injection of a supernatant aliquot into the HPLC system. The separation was achieved on octadecylsilica stationary phase using a mobile phase consisting in a mixture of acetonitrile and water (40:60 (v/v)). The method was then validated using a new approach based on accuracy profiles over a CPA concentration range from 33 to 667 ng/ml for each skin layer. Finally, the method was successfully applied to the determination of CPA to several skin samples after topical application of different gel formulations containing CPA.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Acetato de Ciproterona/análise , Pele/química , Acetato de Ciproterona/farmacocinética , Feminino , Humanos , Técnicas In Vitro , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Pele/metabolismo , Absorção Cutânea , Manejo de Espécimes
16.
AAPS PharmSciTech ; 5(2): e27, 2004 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-15760085

RESUMO

The purpose of this research was to investigate the effects of processing conditions on the characteristics of solid lipid microparticles (SLM) with a potential application as carriers for pulmonary administration. Compritol (5.0% wt/wt) SLM dispersions were prepared by rotor-stator homogenization, at different surfactant concentrations and emulsification times. The SLM were characterized, in terms of morphology and size, after lyophilization and sterilization by autoclaving process. In vivo assessment was carried out in rats by intratracheal instillation of either placebo or SLM dispersion, and by bronchoalveolar lavage for cytological analysis. Mean particle size of 4 to 5 microm was achieved using 0.3% and 0.4% (wt/wt) of emulsifier (Poloxamer 188) and emulsification times of 2 and 5 minutes. The particles showed spherical shape and smooth surface. The morphology of microparticles, the size, and the size distribution were not substantially modified after lyophilization and sterilization. Total cell counts showed no significant differences between placebo and SLM 0.5% or 2.5% groups. Regarding cytology, percentage of polymorphonuclear neutrophils and macrophages did not significantly differ between groups. These results suggest that a single intratracheal administration of the SLMs does not induce a significant inflammatory airway response in rats and that the SLMs might be a potential carrier for encapsulated drug via the pulmonary route.


Assuntos
Portadores de Fármacos , Pulmão , Animais , Química Farmacêutica , Lipídeos , Masculino , Microesferas , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Tecnologia Farmacêutica , Toxicologia
17.
Int J Pharm Compd ; 10(6): 469-77, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-23974421

RESUMO

A study was conducted at the Laboratory of Pharmaceutical Technology, University of Liege, Belgium, of the performance of the Unguator Mixing System, an instrument belonging to a new generation of electronic mortar and pestle apparatus, which was designed to improve pharmaceutical compounding, provide pharmaceutically elegant preparations, and reduce nonproductive time. The goal of this study was to verify that preparations that met the actual quality criteria established by the United States Pharmacopeia, the Therapeutic Compounding Formulary, and the British Pharmacopoeia could be achieved by using the Unguator Mixing System. To achieve this goal, the optimal conditions, such as speed, mixing time, and order of addition of the components, were determined for each of several representative preparations. Two different systems were studied, the Unguator 2000 and the Unguator E/S, and effectiveness of standard and disposable blades was examined. Formulations prepared during the study were tested for appearance, microscopic appearance, and, when judged necessary, uniformity of content. Study results revealed that both models tested were less suitable for preparation of gel bases than for other types bases. Very positive and reproducible results were obtained with compositions containing a low content of active ingredient in hydrophobic ointment or hydrophilic cream. A hydrophobic drug such as clioquinol can be mixed effectively in a hydrophilic carbomer gel with either model, as quantitative assays of different batches showed perfect homogeneity, and microscopic examination found no large agglomerates. Special conditions were required for a material such as benzoyl peroxide which consists of large and hard agglomerates. Salicylic acid hydrophobic 10% ointment can be prepared without any difficulty with both models. Both systems provided full protection for the operator against dust inhalation, since all preparation steps, with the exception of weighing the ingredients, occur in closed containers.

18.
AAPS J ; 7(1): E149-55, 2005 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-16146337

RESUMO

The objective of this study was to determine the pharmacokinetic parameters of miconazole after oral administration of a miconazole/hydroxypropyl-gamma-cyclodextrin(HPgammaCD)/L-tartaric acid inclusion complex produced by supercritical carbon dioxide processing. The pharmacokinetics of the miconazole ternary complex (CPLX), of the corresponding physical mixture (PHYS), and of miconazole alone (MICO) were compared after oral administration. Six mixed-breed pigs received each formulation as a single dose (10 mg miconazole/kg) in a crossover design. Miconazole plasma concentrations were determined by a high-performance liquid chromatography method. Preliminary in vitro dissolution data showed that CPLX exhibits a faster and higher dissolution rate than either PHYS or MICO. Following CPLX oral administration, mean area under the plasma concentration curve (AUC(0-infinity)) for miconazole was 95.0 +/- 55.8 microg/min/mL, with the peak plasma concentration (C(max) 0.59 +/- 0.39 microg/mL) at 19.30 minutes. The AUC(0-infinity) and C(max) values were significantly higher than those after oral administration of PHYS (AUC(0-infinity) 38.5 +/- 12.7 microg/min/mL and C(max) 0.24 +/- 0.08 microg/mL; P < .1) and of MICO (AUC(0-infinity) 24.1 +/- 14.0 microg/min/mL and C(max) 0.1 +/- 0.05 microg/mL; P < .1). There were also significant differences between PHYS and MICO (P < .1). The results of the study indicate that CPLX shows improved dissolution properties and a higher relative oral bioavailability compared with PHYS and MICO.


Assuntos
Cromatografia com Fluido Supercrítico , Miconazol/farmacocinética , Tartaratos/farmacocinética , gama-Ciclodextrinas/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Cápsulas , Dióxido de Carbono , Química Farmacêutica , Misturas Complexas , Feminino , Masculino , Miconazol/administração & dosagem , Solubilidade , Sus scrofa , Tartaratos/administração & dosagem , gama-Ciclodextrinas/administração & dosagem
19.
Pharm Res ; 22(6): 962-71, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15948040

RESUMO

PURPOSE: The aim of the present study was to design a new mucosal drug delivery system composed of liposomes dispersed within a bioadhesive hydrogel containing methyl-beta-cyclodextrin (Me(beta)CD) for controlled drug release. METHODS: A hydrophilic model molecule, inulin, was encapsulated within positively charged and PEG-ylated liposomes and its release was measured in the presence of Me(beta)CD after vesicle dispersion within the bioadhesive Carbopol 974P gel. Freeze-fracture electron microscopy (FFEM) was used to follow liposome morphological changes when dispersed within the hydrogel. Liposome-Me(beta)CD interactions were investigated by turbidity monitoring during continuous addition of Me(beta)CD to liposomes and by FFEM. RESULTS: Inulin diffusion within the gel was influenced by Carbopol 974P concentration since no gel erosion occurred. When dispersed within the gel, positively charged liposomes displayed a higher stability than PEG-ylated vesicles. In the presence of Me(beta)CD, higher amounts of free inulin were released from liposomes, especially in Carbopol-free system. Me(beta)CD appeared to diffuse towards lipid vesicles and permeabilized their bilayer allowing inulin leakage. Indeed, freeze-fracture experiments and liposome turbidity monitoring have shown that Me(beta)CD behaved as a detergent behavior, resulting in lipid vesicle solubilization. CONCLUSION: is able to mediate, within a bioadhesive hydrogel, the release of a liposome-encapsulated molecule allowing further application of this delivery system for mucosal administration.


Assuntos
Preparações Farmacêuticas/administração & dosagem , beta-Ciclodextrinas/química , Resinas Acrílicas , Adesivos , Fenômenos Químicos , Físico-Química , Composição de Medicamentos , Técnica de Fratura por Congelamento , Congelamento , Géis , Inulina/administração & dosagem , Inulina/farmacocinética , Bicamadas Lipídicas , Lipossomos , Microscopia Eletrônica , Nefelometria e Turbidimetria , Polivinil , Solubilidade
20.
Antimicrob Agents Chemother ; 48(11): 4342-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15504863

RESUMO

Because of the central role of dendritic cells and/or Langerhans cells(DC/LC) in the induction of cellular immune responses, pharmacological agents that modulate the recruitment of these cells might have a clinical interest. The present study was designed to evaluate the capacity of several pharmaceutical formulations to topically deliver granulocyte-macrophage colony-stimulating factor (GM-CSF) on human papillomavirus (HPV)-associated genital (pre)neoplastic lesions. The formulations were evaluated for their bioactivity and for their potential to recruit DC in organotypic cultures of HPV-transformed keratinocytes. We found that a bioadhesive polycarbophil gel (Noveon) at pH 5.5 is able to maintain the bioactivity of GM-CSF at 4 or 37 degrees C for at least 7 days, whereas a decreased activity of GM-CSF was observed when the molecule is included in other polymer gels. GM-CSF incorporated in the polycarbophil gel was also a potent factor in enhancing the colonization of DC into organotypic cultures of HPV-transformed keratinocytes since the infiltration of DC in the in vitro-formed (pre)neoplastic epithelium was very low under basal conditions and dramatically increased in the presence of GM-CSF gel. We next demonstrated that GM-CSF incorporated in polycarbophil gel induces the recruitment of human DC in a human (pre)neoplastic epithelium grafted into NOD/SCID mice. The efficacy of GM-CSF in this formulation was equivalent to that observed with liquid GM-CSF. These results suggest that GM-CSF incorporated in polycarbophil gel could play an important role in the recruitment of DC/LC in mucosal surfaces and be useful as a new immunotherapeutic approach for genital HPV-associated (pre)neoplastic lesions.


Assuntos
Células Dendríticas/efeitos dos fármacos , Epitélio/patologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Papillomaviridae , Infecções por Papillomavirus/patologia , Lesões Pré-Cancerosas/patologia , Resinas Acrílicas , Adesivos , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Imunofluorescência , Corantes Fluorescentes , Humanos , Hidrogéis , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Técnicas de Cultura de Órgãos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA