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1.
Energy Fuels ; 35(13): 10898-10907, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34276127

RESUMEN

1D Ca3Co2-z M z O6 (M = Co z = 0, M = Mn z = 1, and M = Fe z = 0.4) were prepared and tested electrochemically. While the iron-containing phase was not found to be active, the iron- and manganese-containing phases were found to be potentially interesting as positive electrode materials for calcium metal-based high-energy battery technologies and were investigated by operando synchrotron X-ray diffraction. Results indicate that electrochemically driven calcium deintercalation from the crystal structure (ca. 0.7 mol per formula unit) takes place upon oxidation in both cases. The oxidized phases have incommensurate modulated crystal structures with the space group R 3m(00γ)0s and a = 9.127(1) Å, c 1 = 2.4226(3) Å and c 2 = 4.1857(3) Å, and γ = 0.579 (M = Co) and a = 9.217(1) Å, c 1 = 4.9076(4) Å and c 2 = 4.3387(4) Å, and γ = 1.139 (M = Mn), which exhibit differences due to the presence of manganese and Mn/Co ordering. The degree of calcium re-intercalation within the structure was found to be extremely limited, if any. Complementary experiments carried out in lithium cells did not show any reversibility either, thus pointing at intrinsic structural/migration constraints in the oxidized phase rather than slow kinetics of high desolvation energies associated with divalent ion charge carriers.

2.
J Pharm Biomed Anal ; 169: 260-268, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30884324

RESUMEN

An integrated chromatographic system was developed to rapidly investigate the biocatalytic properties of ω-transaminases useful for the synthesis of chiral amines. ATA-117, an (R)-selective ω-transaminase was selected as a proof of concept. The enzyme was purified and covalently immobilized on an epoxy monolithic silica support to create an immobilized enzyme reactor (IMER). Reactor efficiency was evaluated in the conversion of a model substrate. The IMER was coupled through a switching valve to an achiral analytical column for separation and quantitation of the transamination products. The best conditions of the transaminase-catalyzed bioconversion were optimized by a design of experiments (DoE) approach. The production of (R)-1-(4-methoxyphenyl)propan-2-amine and (R)-1-methyl-3-phenylpropylamine, intermediates for the synthesis of the bronchodilator formoterol and the antihypertensive dilevalol respectively, was achieved in the presence of different amino donors. The enantiomeric excess (ee) was determined off-line by developing a derivatization procedure using Nα-(2,4-dinitro-5-fluorophenyl)-L-alaninamide reagent. The most satisfactory conversion yields were 60% for (R)-1-(4-methoxyphenyl)propan-2-amine and 29% for (R)-1-methyl-3-phenylpropylamine, using isopropylamine as amino donor. The enantiomeric excess of the reactions were 84%R and 99%R, respectively.


Asunto(s)
Cromatografía/métodos , Enzimas Inmovilizadas/química , Transaminasas/química , Aminación/fisiología , Aminas/química , Biocatálisis , Catálisis , Propilaminas/química , Estereoisomerismo
3.
J Phys Chem C Nanomater Interfaces ; 123(49): 29524-29532, 2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31956392

RESUMEN

Divalent-cation-based batteries are being considered as potential high energy density storage devices. The optimization of electrolytes for these technologies is, however, still largely lacking. Recent demonstration of the feasibility of Ca and Mg plating and stripping in the presence of a passivation layer or an artificial interphase has paved the way for more diverse electrolyte formulations. Here, we exhaustively evaluate several Ca-based electrolytes with different salts, solvents, and concentrations, via measuring physicochemical properties and using vibrational spectroscopy. Some comparisons with Mg- and Li-based electrolytes are made to highlight the unique properties of the Ca2+ cation. The Ca-salt solubility is found to be a major issue, calling for development of new highly dissociative salts. Nonetheless, reasonable salt solubility and dissociation are achieved using bis(trifluoromethanesulfonyl)imide (TFSI), BF4, and triflate anion based electrolytes and high-permittivity solvents, such as ethylene carbonate (EC), propylene carbonate (PC), γ-butyrolactone (gBL), and N,N-dimethylformamide (DMF). The local Ca2+ coordination is concentration-dependent and rather complex, possibly involving bidentate coordination and participation of the nitrogen atom of DMF. The ionicity and the degree of ion-pair formation are both investigated and found to be strongly dependent on the nature of the cation, solvent donicity, and salt concentration. The large ion-ion interaction energies of the contact ion pairs, confirmed by density functional theory (DFT) calculations, are expected to play a major role in the interfacial processes, and thus, we here provide electrolyte design strategies to engineer the cation solvation and possibly improve the power performance of divalent battery systems.

4.
Steroids ; 107: 20-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26718089

RESUMEN

More than 100 filamentous fungi strains, mostly ascomycetes and zygomycetes from different phyla, were screened for the ability to convert deoxycholic acid (DCA) to valuable bile acid derivatives. Along with 11 molds which fully degraded DCA, several strains were revealed capable of producing cholic acid, ursocholic acid, 12-keto-lithocholic acid (12-keto-LCA), 3-keto-DCA, 15ß-hydroxy-DCA and 15ß-hydroxy-12-oxo-LCA as major products from DCA. The last metabolite was found to be a new compound. The ability to catalyze the introduction of a hydroxyl group at the 7(α/ß)-positions of the DCA molecule was shown for 32 strains with the highest 7ß-hydroxylase activity level for Fusarium merismoides VKM F-2310. Curvularia lunata VKM F-644 exhibited 12α-hydroxysteroid dehydrogenase activity and formed 12-keto-LCA from DCA. Acremonium rutilum VKM F-2853 and Neurospora crassa VKM F-875 produced 15ß-hydroxy-DCA and 15ß-hydroxy-12-oxo-LCA, respectively, as major products from DCA, as confirmed by MS and NMR analyses. For most of the positive strains, the described DCA-transforming activity was unreported to date. The presented results expand the knowledge on bile acid metabolism by filamentous fungi, and might be suitable for preparative-scale exploitation aimed at the production of marketed bile acids.


Asunto(s)
Ascomicetos/metabolismo , Ácido Desoxicólico/metabolismo , Hongos no Clasificados/metabolismo , Biotransformación , Catálisis
5.
Chemistry ; 22(5): 1714-21, 2016 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-26692423

RESUMEN

Synthetic sulfonamide derivatives are a class of potent matrix metalloproteinase inhibitors (MMPI) that have potential for the treatment of diseases related to uncontrolled expression of these enzymes. The lack of selectivity of the large majority of such inhibitors, leading to the inhibition of MMPs in tissues other than the targeted one, has dramatically reduced the therapeutic interest in MMPIs. The recent development of efficient drug delivery systems that allow the transportation of a selected drug to its site of action has opened the way to new perspectives in the use of MMPIs. Here, a PAMAM-based divalent dendron with two sulfonamidic residues was synthesized. This nanomolar inhibitor binds to the catalytic domain of two MMPs as well as to the transmembrane human carbonic anhydrases (hCAs) XII, which is present in the eye and considered an antiglaucoma target. In the animal model of an experimental dry eye, no occurrence of dotted staining in eyes treated with our inhibitor was observed, indicating no symptoms of corneal desiccation.


Asunto(s)
Inhibidores de Anhidrasa Carbónica/química , Inhibidores de Anhidrasa Carbónica/farmacología , Síndromes de Ojo Seco/tratamiento farmacológico , Inhibidores de la Metaloproteinasa de la Matriz/química , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Metaloproteinasas de la Matriz/química , Animales , Sistemas de Liberación de Medicamentos , Humanos , Metaloproteinasas de la Matriz/metabolismo
6.
Int J Cosmet Sci ; 37(3): 298-305, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25565399

RESUMEN

OBJECTIVE: The UV filter 3(4-methylbenzylidene) camphor (4-MBC) is a common ingredient in sunscreen cosmetic products. However, different 'in vitro' and 'in vivo' studies suggest that 4-MBC can cause endocrine disrupting effects. Therefore, there is a need for new systems able to minimize the skin penetration of this UV filter. The aim of this study was to evaluate cutaneous permeation and distribution, through and into EPISKIN reconstituted epidermis (RE) from an O/W emulsion containing 4-MBC free or encapsulated in polymeric substantive microspheres. METHODS: Microspheres containing 4-MBC were prepared using the emulsification-solvent evaporation method and characterized for shape and surface morphology and encapsulation efficiency. O/A emulsions containing sunscreen free or encapsulated in microspheres were undergone to permeation tests through RE using vertical diffusion cells. At the end of the in vitro permeation experiments, the skin was subjected to tape stripping procedure to separate stratum corneum from viable epidermis. Each part was properly treated to extract the sunscreen retained and subject to quantitative analysis. RESULTS: The encapsulation of the sunscreen in the microspheres remarkably reduced the permeation of 4-MBC and increased its retention on the skin surface where its action is more desirable. CONCLUSIONS: The results of this study confirm the validity of substantive microspheres as an ideal formulation candidate to use in sunscreen preparation as they appear minimizing its systemic uptake and the potential associate toxicological risks. Therefore, more of the active sunscreen remains on the surface of the skin where it is intended to act and a higher activity it will explicate.


Asunto(s)
Alcanfor/análogos & derivados , Epidermis/metabolismo , Microesferas , Absorción Cutánea , Protectores Solares/farmacocinética , Alcanfor/farmacocinética , Humanos , Modelos Biológicos , Distribución Tisular
7.
Cell Death Dis ; 5: e1097, 2014 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-24603325

RESUMEN

Amyloidogenic 'gain-of-function' mutations in apolipoprotein A-I (ApoA-I) gene (APOA1) result in systemic amyloidosis characterized by aggregate deposition and eventually cell death. However, how amyloidogenic variants of ApoA-I induce cell death is unknown. Here we report that one of the mechanisms by which amyloidogenic ApoA-I induces cell death is through attenuating anti-stress activity of angiogenin (ANG), a homeostatic protein having both pro-growth and pro-survival functions. Under growth conditions, ANG is located in nucleolus where it promotes ribosomal RNA (rRNA) transcription thereby stimulating cell growth. In adverse conditions, ANG is relocated to cytoplasm to promote damage repairs and cell survival. We find that in cells overexpressing the L75P-APOA1 mutant ANG expression is decreased and normal cellular localization of ANG is altered in response to stress and growth signals. In particular, ANG does not relocate to cytoplasm under stress conditions but is rather retained in the nucleolus where it continues promoting rRNA transcription, thus imposing a ribotoxic effect while simultaneously compromising its pro-survival activity. Consistently, we also find that addition of exogenous ANG protects cells from L75P-ApoA-I-induced apoptosis.


Asunto(s)
Proteínas Amiloidogénicas/metabolismo , Apolipoproteína A-I/metabolismo , Variación Genética , Hepatocitos/enzimología , Ribonucleasa Pancreática/metabolismo , Estrés Fisiológico , Proteínas Amiloidogénicas/genética , Apolipoproteína A-I/genética , Apoptosis , Nucléolo Celular/metabolismo , Supervivencia Celular , Células Hep G2 , Hepatocitos/patología , Humanos , Transporte de Proteínas , ARN Ribosómico/metabolismo , Transducción de Señal , Factores de Tiempo , Transcripción Genética , Transfección
8.
Exp Gerontol ; 54: 14-20, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24487345

RESUMEN

Centenarians are rare and exceptional individuals characterized by a peculiar phenotype. They are the best example of healthy aging in humans as most of them have escaped or substantially delayed the onset of major age-related diseases. Within this scenario, the purpose of the present work was to understand if immune status is associated with survival and health status in centenarians. To this aim, 116 centenarians were concomitantly characterized for their immunological, health and functional status, and followed-up for five-year survival. On the basis of previous knowledge we focused on a core of fundamental and basic immune parameters (number of leukocytes, monocytes, total lymphocytes, CD3(+) T lymphocytes, CD4(+) helper T lymphocytes, CD8(+) cytotoxic T lymphocytes, CD19(+) B lymphocytes and plasma levels of IgM), and the most important findings can be summarized as follows: i. a hierarchical cluster analysis was able to define Cluster1 (88 centenarians) and Cluster2 (28 centenarians) characterized by low and high values of all these immune parameters, respectively; ii. centenarians of Cluster2 showed a statistically longer five-year survival and more favorable values of other important immune (naïve, activated/memory and effector/memory T cells) and metabolic (glycemia, insulin and HOMA-IR) parameters, in accord with previous observations that centenarians have a peculiar immune profile, a preserved insulin pathway and a lower incidence of type 2 diabetes; and iii. unexpectedly, parameters related to frailty, as well as functional and cognitive status, did not show any significant correlation with the immune clustering, despite being capable per se of predicting survival. In conclusion, high values of basic immunological parameters and important T cell subsets correlate with five-year survival in centenarians, independent of other phenotypic characteristics. This unexpected biological scenario is compatible with the general hypothesis that in centenarians a progressive disconnection and loss of biological coherence among the different functions of the body occur, where survival/mortality result from the failure of any of these domains which apparently follow an independent age-related trajectory.


Asunto(s)
Inmunidad Adaptativa/fisiología , Estado de Salud , Anciano de 80 o más Años , Linfocitos B/inmunología , Análisis por Conglomerados , Diabetes Mellitus Tipo 2/inmunología , Femenino , Anciano Frágil , Humanos , Memoria Inmunológica/inmunología , Estimación de Kaplan-Meier , Masculino , Linfocitos T/inmunología
9.
Exp Gerontol ; 48(4): 395-400, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23403041

RESUMEN

According to the findings of some recent studies, the centenarians' offspring appear to represent a promising model for research on longevity and healthy aging. This study compares the health status and the functional status of three groups of subjects: 1. individuals with two long-lived parents (one of whom centenarian), 2. individuals with only one long-lived (centenarian) parent, and 3. individuals with no long-lived parents. The goal is to verify whether the centenarians' offspring display any advantage over the offspring of both non-long-lived parents and to evaluate whether the longevity of the non-centenarian parent provides a further advantage. A total of 374 subjects (mean age approximately 70 years) was examined. A threshold for longevity was established for non-centenarian parents through demographic data available for Italy (males surviving to at least 81 years of age and females to 87 years). The participants were assessed for their health and functional status by means of a standardized questionnaire and tests of physical performance. Data were analyzed using multivariate regression models adjusted for socio-demographic characteristics and risk factors for age-related pathologies. The results of the study show that centenarians' offspring have a better functional status, a reduced risk for several age-related pathologies and reduced drug consumption than the offspring of non-long-lived parents. In addition, the health status of centenarians' offspring does not appear to be influenced by the longevity of the second parent. It therefore seems possible to conclude that at ages around 70 years the genetic contribution to health status deriving from having one centenarian parent is not substantially improved if the other parent is also long-lived.


Asunto(s)
Niños Adultos , Evaluación Geriátrica/estadística & datos numéricos , Disparidades en el Estado de Salud , Esperanza de Vida , Longevidad/fisiología , Padres , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Censos , Demografía , Femenino , Humanos , Italia/epidemiología , Masculino , Análisis de Regresión , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios , Análisis de Supervivencia
10.
Steroids ; 78(3): 370-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23333587

RESUMEN

Selected actinobacteria and filamentous fungi of different taxonomy were screened for the ability to carry out regio- and stereospecific hydroxylation of lithocholic acid (LCA) at position 7ß. The production of ursodeoxycholic acid (UDCA) was for the first time shown for the fungal strains of Bipolaris, Gibberella, Cunninghamella and Curvularia, as well as for isolated actinobacterial strains of Pseudonocardia, Saccharothrix, Amycolatopsis, Lentzea, Saccharopolyspora and Nocardia genera. Along with UDCA, chenodeoxycholic (CDCA), deoxycholic (DCA), cholic (CA), 7-ketodeoxycholic and 3-ketodeoxycholic acids were detected amongst the metabolites by some strains. A strain of Gibberella zeae VKM F-2600 expressed high level of 7ß-hydroxylating activity towards LCA. Under optimized conditions, the yield of UDCA reached 90% at 1g/L of LCA and up to 60% at a 8-fold increased substrate loading. The accumulation of the major by-product, 3-keto UDCA, was limited by using selected biotransformation media.


Asunto(s)
Actinobacteria/metabolismo , Ascomicetos/metabolismo , Ácido Litocólico/metabolismo , Biotransformación , Ácido Quenodesoxicólico/metabolismo , Ácido Cólico/metabolismo , Ácido Desoxicólico/análogos & derivados , Ácido Desoxicólico/metabolismo , Hidroxilación , Espectroscopía de Resonancia Magnética , Estereoisomerismo , Ácido Ursodesoxicólico/metabolismo
11.
J Eur Acad Dermatol Venereol ; 27(2): e153-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22449201

RESUMEN

BACKGROUND: In a previous study a new hydrosoluble nail lacquer (P-3051) containing 8% ciclopirox (CPX) showed higher nail penetration compared to a water-insoluble 5% amorolfine (MRF) lacquer. To our knowledge, in vivo human data on a similar topic are not available. OBJECTIVES: To compare fingernail penetration of P-3051 with that of MRF reference in humans and to evaluate their predicted efficacy against Trichophyton rubrum and Candida parapsilosis. METHODS: Single centre, randomized, multiple dose, open label, within subjects study. Test and reference were self-applied to all fingernails of either hand for 28 days. At baseline and after 15 and 25 days, the nail free edge was collected for analysis. Efficiency coefficients were calculated for T. rubrum and C. parapsilosis as ratios of nail concentration/minimum inhibitory concentration. The coefficients were classified as very high, high or poor. RESULTS: Nail concentrations after 15 days were 2.82 ± 0.58 µg/mg for CPX and 0.64 ± 0.11 µg/mg for MRF. At day 25 there was a non-significant decline (1.85 ± 0.31 µg/mg, P = 0.077) for CPX and a highly significant (0.13 ± 0.03 µg/mg, P = 0.0002) 80% decline for MRF. Efficiency coefficients were very high/high in all subjects treated with P-3051 against both T. rubrum and C. parapsilosis; they were significantly lower for MRF reference against both pathogens at both observation points. CONCLUSIONS: P-3051 exhibited better penetration and higher predicted efficacy after in vivo multiple application to human fingernails when compared to MRF reference. These in vivo data are in good agreement with our previous in vitro study.


Asunto(s)
Morfolinas/uso terapéutico , Uñas/metabolismo , Onicomicosis/prevención & control , Piridonas/uso terapéutico , Adulto , Ciclopirox , Humanos , Masculino , Persona de Mediana Edad , Morfolinas/administración & dosificación , Morfolinas/farmacocinética , Piridonas/administración & dosificación , Piridonas/farmacocinética , Valores de Referencia
12.
Age (Dordr) ; 35(5): 1995-2007, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23138631

RESUMEN

With aging, an increased prevalence of a clustering of metabolic abnormalities has been observed. These abnormalities include obesity, dyslipidemia, hypertension, and insulin resistance and are collectively known as metabolic syndrome (MetS), a low-grade, systemic, inflammatory condition associated with an increased risk of cardiovascular disease, diabetes, and other adverse health outcomes. A number of studies have demonstrated that centenarians' offspring have a significant survival advantage and a lower risk of developing the most important age-related diseases. They therefore represent one of the best models with which to study the familiar component of human longevity. The aim of this study was to determine if the offspring of centenarians (n = 265 subjects) showed a different prevalence of MetS in comparison to the offspring of non-long-lived parents (controls, n = 101 subjects). In addition, we assessed whether centenarians' offspring showed particular features of MetS and a distinct regulation of circulating adipokines, cytokines, and metabolic mediators. Although the prevalence of MetS was quite similar both in the offspring of centenarians and the controls, MetS-affected centenarians' offspring seemed healthier, more functionally fit, and had lower resistin levels. MetS prevalence did not change in centenarians' offspring across resistin, IGF-1, and resistin/IGF-1 ratio tertiles. On the other hand, in controls, MetS prevalence strongly increased across resistin tertiles and in the third resistin/IGF-1 ratio tertile, indicating a dramatic increase in MetS prevalence when the ratio between these two factors is unbalanced, with high levels of resistin and low levels of IGF-1.


Asunto(s)
Adipoquinas/sangre , Envejecimiento , Síndrome Metabólico/epidemiología , Padres , Anciano , Femenino , Humanos , Italia/epidemiología , Masculino , Síndrome Metabólico/sangre , Prevalencia , Factores de Riesgo
13.
Br J Dermatol ; 165(1): 99-105, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21410668

RESUMEN

BACKGROUND: Topical therapy has recently been proposed for treating onychomycosis and other nail disturbances. However, the clinical outcome may be limited by the difficulty of active ingredients effectively penetrating the nail plate. Bovine hoof membranes have been widely used to predict in vitro efficacy of drug products in nail diseases. Many studies have compared bovine hooves with human healthy nails, considering the difference between healthy and unhealthy nails to be negligible. OBJECTIVES: To validate bovine hoof slices as a model for human unhealthy nails by investigating the transungual permeation/retention of ciclopirox (CPX) through bovine hoof slices and excised infected human toenails after application of a new film-forming formulation (P-3051). To investigate the ability of CPX to achieve fungicidal concentrations in and through infected toenails. METHODS: A new experimental technique based on a permeation unit allowed analysis by high-performance liquid chromatography of the amounts of CPX permeating through and retained in the membranes. The efficacy index was evaluated as follows: amount of permeated CPX/Trichophyton rubrum minimum inhibiting concentration. RESULTS: Extrapolated CPX flux through bovine hoof slices was about 14-fold higher than through infected human toenails, the difference being mainly due to the fourfold higher thickness of the toenails. In toenails, the CPX efficacy index for T. rubrum was positive (>1·0) soon after P-3051 application. CONCLUSIONS: This study confirms the validity of bovine hoof slices as a model for infected human nails, and suggests a substantial equivalence between the two models. Following P-3051 application, CPX reaches fungicidal concentrations in and through human infected toenails.


Asunto(s)
Antifúngicos/farmacocinética , Pezuñas y Garras/efectos de los fármacos , Onicomicosis/tratamiento farmacológico , Piridonas/farmacocinética , Trichophyton/efectos de los fármacos , Administración Tópica , Animales , Antifúngicos/administración & dosificación , Bovinos , Ciclopirox , Modelos Animales de Enfermedad , Pezuñas y Garras/metabolismo , Humanos , Laca , Uñas/efectos de los fármacos , Uñas/metabolismo , Permeabilidad , Piridonas/administración & dosificación
14.
Eur J Pharm Biopharm ; 76(3): 443-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20832470

RESUMEN

In this investigation two vitamin C-based -6-O-ascorbic acid esters (ASC12 and ASC16), able to form liquid-crystal structures (coagels) was evaluated for their potential usefulness to promote the permeation and distribution of ibuprofen (IBU). Two coagel formulations and the same coagels added of polyethylene glycol (PEG-400) were assayed in comparison with a commercial product (Arfen®) by using hairless rat skin as model. The ASC16 and ASC12 derivatives gave rise to stable supramolecular assemblies in water and in water/PEG mixtures (coagels), allowing the solubilization of IBU (0.85%) and producing a IBU controlled release systems, as evidenced by the dynamic dialyse test: the n values were near 1.0, indicative of a linear kinetic, for all coagel formulations, except for the ASC12PEG/C formulation (n=1.51). Our results evidenced the enhancement activity of coagels and the synergic effect of the combination with PEG: all coagels showed a higher amount of IBU permeated through the skin compared to commercial Arfen® with an enhancement factor of 52.94 and 21.53 for ASC12PEG/C and ASC16/C respectively. Otherwise, coagels formulations appeared to produce a low IBU depot in the skin and in the same order of magnitude in epidermis and derma, in spite of significant increase of IBU cutaneous permeation. The positive synergic effect of the coagel-PEG mixtures was demonstrated by the high amount of IBU accumulated in the upper skin layers. The effect of the coagels on the IBU skin permeation and distribution depending on their hydro-lipophilic character could allow a rational design and an optimization of topical formulations.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacocinética , Sistemas de Liberación de Medicamentos , Ibuprofeno/farmacocinética , Nanoestructuras , Piel/metabolismo , Administración Cutánea , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/análisis , Antiinflamatorios no Esteroideos/farmacología , Ácido Ascórbico/análogos & derivados , Ibuprofeno/administración & dosificación , Ibuprofeno/análisis , Ibuprofeno/farmacología , Masculino , Permeabilidad/efectos de los fármacos , Polietilenglicoles , Ratas , Ratas sin Pelo , Piel/efectos de los fármacos , Absorción Cutánea
15.
Int J Pharm ; 400(1-2): 32-6, 2010 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-20728514

RESUMEN

Aim of this research was to evaluate novel microspheres based on poloxamer 407, alone or in mixture with Gelucire(®) 50/13, as possible buccal delivery system for atenolol (AT). The microspheres have been prepared by spray congealing and investigated to assess AT in vitro delivery through cellulose membranes and ex vivo permeation using porcine buccal mucosa. The microparticles were tested as such or directly compacted to obtain tablets. For comparison the physical mixtures, tablets of the physical mixtures and an AT solution were examined. Finally, the microparticles were sublingually administered in rabbits to evaluate AT pharmacokinetics compared to a market oral tablet (reference). The AT release from microspheres through the synthetic membrane was delayed with respect to the drug solution, more markedly when microparticles contained poloxamer as unique adjuvant; this formulation enhanced AT transmucosal permeation. The enhancement effect of poloxamer was confirmed by the permeation experiments on the corresponding physical mixture. Tabletting hindered both release through cellulose membranes and transmucosal permeation of drug. In vivo studies revealed that the absolute bioavailability of microsphere formulations was higher than that of reference in spite of a lower dosage of drug, suggesting a possible dose reduction by AT microparticles orotransmucosal administration.


Asunto(s)
Antagonistas de Receptores Adrenérgicos beta 1/administración & dosificación , Atenolol/administración & dosificación , Mucosa Bucal/metabolismo , Poloxámero/química , Administración Bucal , Administración Sublingual , Antagonistas de Receptores Adrenérgicos beta 1/química , Antagonistas de Receptores Adrenérgicos beta 1/farmacocinética , Animales , Atenolol/química , Atenolol/farmacocinética , Disponibilidad Biológica , Química Farmacéutica , Portadores de Fármacos , Femenino , Técnicas In Vitro , Microesferas , Permeabilidad , Polietilenglicoles/química , Conejos , Solubilidad , Porcinos , Comprimidos
16.
Int J Pharm ; 399(1-2): 71-9, 2010 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-20696227

RESUMEN

The two-part article aimed to investigate poloxamer 407-based microspheres as a novel platform for enhancing and controlling the delivery of atenolol across the oromucosal tissue. In the Part I of the work, atenolol-loaded poloxamers 407 microparticles were prepared by the solvent free spray congealing technology. This approach was feasible upon the high viscosity of the systems allowing for high loaded (20% w/w) non-aggregated microspheres. Several formulations were studied and the results demonstrated that the drug release patterns, solubility data, mucoadhesion to buccal tissue and gelling properties in saliva could be modified by adding different amount of an amphiphilic polymer-lipid excipient (Gelucire(®) 50/13) to poloxamer 407. Particularly, microspheres based only on poloxamer 407 exhibited very high solubility, mucoadhesive strength and gelling behaviour. To assess their potential as matrix for buccal application, the gelling property and the drug release from tablets obtained from direct compression of the microparticles were further evaluated. The microspheres were then characterized by differential scanning calorimetry, X-ray powder diffraction and Fourier transform-infrared spectra analysis. No solid state modifications and chemical interactions were detectable in the microspheres after manufacturing and during storage, suggesting their stability and use as orotransmucosal delivery systems.


Asunto(s)
Química Farmacéutica/métodos , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Mucosa Bucal/metabolismo , Preparaciones Farmacéuticas/administración & dosificación , Poloxámero/química , Administración Oral , Rastreo Diferencial de Calorimetría , Humanos , Microscopía Electrónica de Rastreo , Microesferas , Tamaño de la Partícula , Permeabilidad , Preparaciones Farmacéuticas/química , Difracción de Polvo , Saliva/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Comprimidos , Viscosidad , Difracción de Rayos X
17.
Curr Pharm Des ; 16(7): 802-13, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20388091

RESUMEN

Human aging and longevity are complex and multi-factorial traits that result from a combination of environmental, genetic, epigenetic and stochastic factors, each contributing to the overall phenotype. The multi-factorial process of aging acts at different levels of complexity, from molecule to cell, from organ to organ systems and finally to organism, giving rise to the dynamic "aging mosaic". At present, an increasing amount of experimental data on genetics, genomics, proteomics and other -omics are available thanks to new high-throughput technologies but a comprehensive model for the study of human aging and longevity is still lacking. Systems biology represents a strategy to integrate and quantify the existing knowledge from different sources into predictive models, to be later tested and then implemented with new experimental data for validation and refinement in a recursive process. The ultimate goal is to compact the new acquired knowledge into a single picture, ideally able to characterize the phenotype at systemic/organism level. In this review we will briefly discuss the aging phenotype in a systems biology perspective, showing four specific examples at different levels of complexity, from a systemic process (inflammation) to a cascade-process pathways (coagulation) and from cellular organelle (proteasome) to single gene-network (PON-1), which could also represent targets for anti-aging strategies.


Asunto(s)
Envejecimiento/fisiología , Longevidad/fisiología , Biología de Sistemas , Factores de Edad , Diseño de Fármacos , Humanos , Modelos Biológicos
18.
Br J Dermatol ; 162(2): 311-7, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19886884

RESUMEN

BACKGROUND: Two nail lacquers, containing ciclopirox (CPX) or amorolfine (MRF), based on water-insoluble polymers are currently considered mainstays of topical treatment of onychomycosis. The present study aimed at evaluating the antimycotic activity of a new water-soluble nail lacquer containing CPX (CPX/sol), easily removable by washing with water and applicable to periungual skin. OBJECTIVES: To compare transungual permeation of CPX with that of MRF in the same hydroxypropyl chitosan-based nail lacquer (MRF/sol) and with a nonwater-soluble reference (Loceryl); Galderma International, La Défense, France), and to evaluate the antimycotic activity of CPX/sol and Loceryl against the most common fungal strains that cause onychomycosis. Methods In vitro drug permeation experiments with CPX/sol, MRF/sol and Loceryl were carried out through bovine hoof slices. Experimental permeates from CPX/sol and Loceryl underwent in vitro susceptibility testing against clinical isolates of dermatophytes, moulds and yeast. Results MRF transungual flux from MRF/sol lacquer was significantly higher when compared with Loceryl. CPX was able to permeate hoof membranes more easily compared with MRF. CPX and MRF concentrations in the subungual fluids collected after application of CPX/sol or Loceryl were sufficient to inhibit fungal growth, with the exception of Candida parapsilosis. Smaller amounts of fluid containing CPX were required for complete inhibition of fungal growth. Efficacy index values were significantly higher for CPX/sol. Conclusions Application of the CPX/sol nail lacquer allows rapid nail penetration of CPX, providing CPX levels sufficient to inhibit fungal growth for a prolonged period of time (30 h) after application of lacquer dose. CPX/sol nail lacquer appeared superior to the market reference Loceryl in terms of both vehicle (hydroxypropyl chitosan) and active ingredient (CPX) as witnessed by its higher efficacy on all nail pathogens.


Asunto(s)
Antifúngicos/administración & dosificación , Laca , Morfolinas/administración & dosificación , Onicomicosis/tratamiento farmacológico , Piridonas/administración & dosificación , Absorción , Administración Tópica , Animales , Antifúngicos/farmacocinética , Bovinos , Ciclopirox , Pezuñas y Garras , Humanos , Morfolinas/farmacocinética , Uñas , Onicomicosis/metabolismo , Permeabilidad , Soluciones Farmacéuticas/administración & dosificación , Vehículos Farmacéuticos , Piridonas/farmacocinética , Análisis de Regresión , Solubilidad
19.
Drug Deliv ; 16(5): 237-42, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19538003

RESUMEN

Previous studies in vitro had identified niaouli essential oil (NEO) as a valuable transdermal permeation promoter for estradiol (ES). Subsequent considerations on the complex issue of NEO provenance and composition stimulated the present investigation, which was aimed at defining the composition of NEOs obtained from four different sources, at evaluating their influence on transdermal permeation of ES through hairless mouse skin, and at formulating and evaluating simpler terpene mixtures mimicking the NEOs' composition. While all oils contained 1,8-cineol (eucalyptol) as the main component, appreciable variations in composition could be evidenced, originating differences on the ES cutaneous permeation. Two artificial mixtures containing the same proportions of the main terpenes present in each oil (except the commercially unavailable gamma-terpineol) proved equal or significantly superior in activity when compared with the original oils. It is felt that this study might contribute to the formulation of terpene mixtures acting more efficiently and reproducibly with respect to natural NEOs, whose complex and variable composition, depending on growing place, season, and extraction process, is well documented in the relevant literature.


Asunto(s)
Administración Cutánea , Estradiol/administración & dosificación , Melaleuca/química , Aceites Volátiles/administración & dosificación , Absorción Cutánea/efectos de los fármacos , Terpenos/administración & dosificación , Animales , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/farmacología , Sistemas de Liberación de Medicamentos , Estradiol/metabolismo , Femenino , Ratones , Ratones Pelados , Aceites Volátiles/química , Permeabilidad/efectos de los fármacos , Tecnología Farmacéutica , Terpenos/química , Terpenos/farmacología
20.
Neuroimmunomodulation ; 15(4-6): 224-40, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19047800

RESUMEN

At present, individuals can live up to 80-120 years, a time much longer than that of our ancestors, as a consequence of the improvements in life conditions and medical care. Thus, the human immune system has to cope with a lifelong and evolutionarily unpredicted exposure to a variety of antigens, which are at the basis of profound age-related changes globally indicated as immunosenescence, a multifaceted phenomenon that increases morbidity and mortality due to infections and age-related pathologies. The major changes occurring during immunosenescence are the result of the accumulation of cellular, molecular defects and involutive phenomena (such as thymic involution) occurring concomitantly to a hyperstimulation of both innate and adaptive immunity (accumulation of expanded clones of memory and effector T cells, shrinkage of the T cell receptor repertoire, progressive activation of macrophages), and resulting in a low-grade, chronic state of inflammation defined as inflammaging. It is unknown whether inflammaging, which represents a risk factor for most age-related pathologies, is a cause or rather an effect of the aging process. In this complex scenario, the role of genetic background likely represents a fundamental variable to attain successful aging and longevity. Accordingly, centenarians seem to be equipped with gene variants that allow them to optimize the balance between pro- and anti-inflammatory molecules, and thus to minimize the effects of the lifelong exposure to environmental insults and stressors. The remarkable features of the genetics of aging and longevity are reviewed, stressing the unexpected and unusual results obtained regarding such a postreproductive type of genetics.


Asunto(s)
Envejecimiento/inmunología , Fenómenos Inmunogenéticos , Longevidad/fisiología , Tejido Adiposo/fisiología , Anciano , Anciano de 80 o más Años , Envejecimiento/genética , Antígenos Virales/inmunología , Atrofia , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/fisiopatología , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/fisiopatología , Humanos , Inmunidad Celular/genética , Inmunidad Celular/inmunología , Inmunocompetencia/genética , Inmunocompetencia/inmunología , Infecciones/genética , Infecciones/inmunología , Inflamación/genética , Inflamación/inmunología , Interleucinas/genética , Interleucinas/inmunología , Interleucinas/fisiología , Longevidad/genética , Longevidad/inmunología , Persona de Mediana Edad , Neoplasias/genética , Neoplasias/inmunología , Subgrupos de Linfocitos T/inmunología , Timo/patología
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