22 research outputs found
Bacterioruberin from Haloarchaea plus dexamethasone in ultra-small macrophage-targeted nanoparticles as potential intestinal repairing agent
Oral administration of antioxidant and anti-inflammatory drugs have the potential to improve the current therapy of inflammatory bowel disease. Success of oral treatments, however, depends on the capacity of drugs to remain structurally stable along the gastrointestinal tract, and on the feasibility of accessing the target cells. Delivering anti-inflammatory and antioxidant drugs to macrophages using targeted nanoparticles, could make treatments more efficient. In this work structural features and in vitro activity of macrophage-targeted nanostructured archaeolipid carriers (NAC) containing the high antioxidant dipolar C50 carotenoid bacterioruberin (BR) plus dexamethasone (Dex): NAC-Dex, are described. Ultra-small (66 nm), -32 mV potential, 1200 g Dex /ml NAC-Dex, consisted of a compritol and BR core, covered by a shell of sn 2,3 ether linked archaeolipids and Tween 80 (2: 2: 1.2: 3 % w/w) were obtained. NAC-Dex were extensively captured by macrophages and Caco-2 cells and displayed high anti-inflammatory and antioxidant activities on a gut inflammation model made of Caco-2 cells and lipopolysaccharide stimulated THP-1 derived macrophages reducing 65 % and 55 % TNF- and IL-8 release, respectively and 60 % reactive oxygen species production. NAC-Dex also reversed the morphological changes induced by inflammation and increased the transepithelial electrical resistance, partly reconstituting the barrier function. Activity of BR and Dex in NAC-Dex was partially protected after simulated gastrointestinal digestion, improving the chances of BR-Dex joint activity. Results suggest that oral NAC-Dex deserve further exploration as intestinal barrier repairing agent.Fil: Higa, Leticia Herminia. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Schilrreff, Priscila. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; ArgentinaFil: Briski, AndrĂ©s MartĂn. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; ArgentinaFil: Jerez, Horacio Emanuel. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: de Farias, Marcelo Alexandre. Brazilian Nanotechnology National Laboratory; BrasilFil: Villares Portugal, Rodrigo. Brazilian Nanotechnology National Laboratory; BrasilFil: Romero, Eder Lilia. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Morilla, MarĂa JosĂ©. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
The anti MRSA biofilm activity of Thymus vulgaris essential oil in nanovesicles
Background: Thymus vulgaris essential oil (T) could be an alternative to classical antibiotics against bacterial biofilms, which show increased tolerance to antibiotics and host defence systems and contribute to the persistence of chronic bacterial infections. Hypothesis: A nanovesicular formulation of T may chemically protect the structure and relative composition of its multiple components, potentially improving its antibacterial and antibiofilm activity. Study design: We prepared and structurally characterized T in two types of nanovesicles: nanoliposomes (L80-T) made of Soybean phosphatidylcholine (SPC) and Polysorbate 80 (P80) [SPC:P80:T 1:0.75:0.3 w:w], and nanoarchaeosomes (A80-T) made of SPC, P80 and total polar archaeolipids (TPA) extracted from archaebacteria Halorubrum tebenquichense [SPC:TPA:P80:T 0.5:0.50.75:0.7 w:w]. We determined the macrophage cytotoxicity and the antibacterial activity against Staphylococcus aureus ATCC 25,923 and four MRSA clinical strains. Results: L80-T (Z potential â4.1 ± 0.6 mV, ⌠115 nm, ⌠22 mg/ml T) and A80-T (Z potential â6.6 ± 1.5 mV, ⌠130 nm, ⌠42 mg/ml T) were colloidally and chemically stable, maintaining size, PDI, Z potential and T concentration for at least 90 days. While MIC 90 of L80-T was > 4 mg/ml T, MIC 90 of A80-T was 2 mg/ml T for all S. aureus strains. The antibiofilm formation activity was maximal for A80-T, while L80-T did not inhibit biofilm formation compared to untreated control. A80-T significantly decreased the biomass of preformed biofilms of S. aureus ATCC 25,923 strain and of 3 of the 4 clinical MRSA isolates at 4 mg/ml T. It was found that the viability of J774A.1 macrophages was decreased significantly upon 24 h incubation with A80-T, L80-T and T emulsion at 0.4 mg/ml T. These results show that from 0.4 mg/ml T, a value lower than MIC 90 and the one displaying antibiofilm activity, with independence of its formulation, T significantly decreased the macrophages viability. Conclusion: Overall, because of its lower MIC 90 against planktonic bacteria, higher antibiofilm formation capacity and stability during storage, A80-T resulted better antibacterial agent than T emulsion and L80-T. These results open new avenues to explode the A80-T antimicrobial intracellular activity.Fil: Perez, Ana Paula. Universidad Nacional de San MartĂn. Escuela de Ciencia y TecnologĂa; ArgentinaFil: Perez, Noelia Soledad. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de San MartĂn. Escuela de Ciencia y TecnologĂa; ArgentinaFil: Suligoy Lozano, Carlos Mauricio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Altube, MarĂa Julia. Universidad Nacional de San MartĂn. Escuela de Ciencia y TecnologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: de Farias, Marcelo Alexandre. No especifĂca;Fil: Portugal, Rodrigo Villares. No especifĂca;Fil: Buzzola, Fernanda Roxana. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Morilla, MarĂa JosĂ©. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de San MartĂn. Escuela de Ciencia y TecnologĂa; ArgentinaFil: Romero, Eder Lilia. Universidad Nacional de San MartĂn. Escuela de Ciencia y TecnologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
Studies of macromolecular complexes using electron cryo-electron microscopy and biophysical techniques
Este trabalho apresenta o estudo e caracterização de dois complexos moleculares, hRXRĂĄlfadeltaAB e hemocianina de Acanthoscurria gomesiana, atravĂ©s de tĂ©cnicas estruturais e biofĂsicas. O uso da tĂ©cnica de crio-microscopia eletrĂŽnica para o estudo da hemocianina de Acanthoscurria gomesiana, resultou em um modelo estrutural com resolução de 14 angstron- pelo mĂ©todode Fourier Shell Correlation com critĂ©rio de 1/2 bit. Neste limite de resolução, jĂĄ Ă© possĂvel observar detalhes estruturais que o mostram como sendo comptĂvel com outros modelos de hemocianinas. Com relação ao estudo de hRXRalfadeltaAB, mostrou-se, atravĂ©s das tĂ©cnicas de cromatografia analĂtica de exclusĂŁo por tamanho, eletroforese de gel de poliacrilamida e SAXS, que a proteĂna pode se apresentar no estado dimĂ©rico em solução, mesmo na ausĂȘncia do seu ligante, 9-cis-RA. TambĂ©m foi estudado a associação de hRXRalfadeltaAB a elementos responsivos: DR1, DR4, F2 e PAL. Suas constantes de dissociação foram calculadas atravĂ©s da tĂ©cnica de espectroscopia por anisotropia de fluorescĂȘncia. Os resultados obtidos mostram maior afinidade por DR1 e DR2 e indicam uma origem entrĂłpica para o processo de associaçãoThis work describes characterization of two biomolecular complexes: hRXR deltaAB and a hemocyanin from Acanthoscurria gomesiana using structural and biophysical techniques. Application of cryo-electron microscopy to studies of a hemocyanin from Acanthoscurria gomesiana resulted in its structural model to 14Ă
resolution, which was calculated by Fourier Shell Correlation with cut-off of 1/2 bit. At this resolution limit one can observe structural details of the complex which are compatible with other hemocyanin models. With respect to hRXR deltaAB, we showed using analytic size exclusion chromatography, SDS PAGE and SAXS, that the protein is dimeric in solution even at the absence of its ligand, 9-cis-RA. hRXR deltaAB binding to the responsive elements of DNA, DR1, DR4, F2 and PAL was investigated and the binding constants to these responsive elements have been determined using fluorescence anisotropy technique. Our results show higher affinity of the receptor to DR1 and DR4 and indicate entropic mechanism of DNA bindin
Not available
Este trabalho descreve o desenvolvimento da interface com o usuĂĄrio para um tomĂłgrafo por ressonĂąncia magnĂ©tica, a ser instalado na Santa Casa de SĂŁo Carlos. O objetivo desta interface Ă© permitir, ao usuĂĄrio clĂnico, uma fĂĄcil e rĂĄpida operaçãodo sistema. Os principais resultados obtidos foram a especificação dos requisitos, do sistema a ser desenvolvido, e uma implementação parcial da interface com o usuĂĄrio. Durante este projeto, tambĂ©m foram desenvolvidos dois outros programas:PosProc, que automatiza o pĂłs-processamento de imagens, no sistema jĂĄ instalado no IFSC, e TORM Image, um programa para visualização de imagens no formato IMR, tambĂ©m desenvolvido no grupo. AlĂ©m disso, foi implementado um site na internet, paradivulgar aspectos relativos ao grupo de MRI do IFSC/USP - SĂŁo Carlos e Ă prĂłpria tĂ©cnica. Foi implementada uma versĂŁo inicial de uma ferramenta para avaliação clĂnica utilizando a Internet, projeto este que ainda estĂĄ em andamentoThis work describes the development of a user interface to a magnetic resonance scanner, to be installed at Sanmta Casa in SĂŁo Carlos. The objective of this interface is to allow, to the clinical user, an easy and fast operation of the system. The major results obtained were the requirement specification, of the system to be developed, and a partial implementation of the user interface. During this project two other programs were also developed: PosProc, that automates the post-processing of images, in the system already installed in IFSC, and Torm Image, a vizualization program for IMR images, a local standard. Furthermore, an internet site was implemented to get across aspects related to the MRI group of IFSC/USP - SĂŁo Carlos and the technique itself. It was implemented a primer version of an Internet clinical valuation web tool. This project is still going o
Not available
Este trabalho descreve o desenvolvimento da interface com o usuĂĄrio para um tomĂłgrafo por ressonĂąncia magnĂ©tica, a ser instalado na Santa Casa de SĂŁo Carlos. O objetivo desta interface Ă© permitir, ao usuĂĄrio clĂnico, uma fĂĄcil e rĂĄpida operaçãodo sistema. Os principais resultados obtidos foram a especificação dos requisitos, do sistema a ser desenvolvido, e uma implementação parcial da interface com o usuĂĄrio. Durante este projeto, tambĂ©m foram desenvolvidos dois outros programas:PosProc, que automatiza o pĂłs-processamento de imagens, no sistema jĂĄ instalado no IFSC, e TORM Image, um programa para visualização de imagens no formato IMR, tambĂ©m desenvolvido no grupo. AlĂ©m disso, foi implementado um site na internet, paradivulgar aspectos relativos ao grupo de MRI do IFSC/USP - SĂŁo Carlos e Ă prĂłpria tĂ©cnica. Foi implementada uma versĂŁo inicial de uma ferramenta para avaliação clĂnica utilizando a Internet, projeto este que ainda estĂĄ em andamentoThis work describes the development of a user interface to a magnetic resonance scanner, to be installed at Sanmta Casa in SĂŁo Carlos. The objective of this interface is to allow, to the clinical user, an easy and fast operation of the system. The major results obtained were the requirement specification, of the system to be developed, and a partial implementation of the user interface. During this project two other programs were also developed: PosProc, that automates the post-processing of images, in the system already installed in IFSC, and Torm Image, a vizualization program for IMR images, a local standard. Furthermore, an internet site was implemented to get across aspects related to the MRI group of IFSC/USP - SĂŁo Carlos and the technique itself. It was implemented a primer version of an Internet clinical valuation web tool. This project is still going o
Studies of macromolecular complexes using electron cryo-electron microscopy and biophysical techniques
Este trabalho apresenta o estudo e caracterização de dois complexos moleculares, hRXRĂĄlfadeltaAB e hemocianina de Acanthoscurria gomesiana, atravĂ©s de tĂ©cnicas estruturais e biofĂsicas. O uso da tĂ©cnica de crio-microscopia eletrĂŽnica para o estudo da hemocianina de Acanthoscurria gomesiana, resultou em um modelo estrutural com resolução de 14 angstron- pelo mĂ©todode Fourier Shell Correlation com critĂ©rio de 1/2 bit. Neste limite de resolução, jĂĄ Ă© possĂvel observar detalhes estruturais que o mostram como sendo comptĂvel com outros modelos de hemocianinas. Com relação ao estudo de hRXRalfadeltaAB, mostrou-se, atravĂ©s das tĂ©cnicas de cromatografia analĂtica de exclusĂŁo por tamanho, eletroforese de gel de poliacrilamida e SAXS, que a proteĂna pode se apresentar no estado dimĂ©rico em solução, mesmo na ausĂȘncia do seu ligante, 9-cis-RA. TambĂ©m foi estudado a associação de hRXRalfadeltaAB a elementos responsivos: DR1, DR4, F2 e PAL. Suas constantes de dissociação foram calculadas atravĂ©s da tĂ©cnica de espectroscopia por anisotropia de fluorescĂȘncia. Os resultados obtidos mostram maior afinidade por DR1 e DR2 e indicam uma origem entrĂłpica para o processo de associaçãoThis work describes characterization of two biomolecular complexes: hRXR deltaAB and a hemocyanin from Acanthoscurria gomesiana using structural and biophysical techniques. Application of cryo-electron microscopy to studies of a hemocyanin from Acanthoscurria gomesiana resulted in its structural model to 14Ă
resolution, which was calculated by Fourier Shell Correlation with cut-off of 1/2 bit. At this resolution limit one can observe structural details of the complex which are compatible with other hemocyanin models. With respect to hRXR deltaAB, we showed using analytic size exclusion chromatography, SDS PAGE and SAXS, that the protein is dimeric in solution even at the absence of its ligand, 9-cis-RA. hRXR deltaAB binding to the responsive elements of DNA, DR1, DR4, F2 and PAL was investigated and the binding constants to these responsive elements have been determined using fluorescence anisotropy technique. Our results show higher affinity of the receptor to DR1 and DR4 and indicate entropic mechanism of DNA bindin
Surviving nebulization-induced stress: dexamethasone in pH-sensitive archaeosomes
Aim: To increase the subcellular delivery of dexamethasone phosphate (DP) and stability to nebulization stress, pH-sensitive nanoliposomes (LpH) exhibiting archaeolipids, acting as ligands for scavenger receptors (pH-sensitive archaeosomes [ApH]), were prepared. Materials & methods: The anti-inflammatory effect of 0.18 mg DP/mg total lipid, 100â150 nm DP-containing ApH (dioleylphosphatidylethanolamine: Halorubrum tebenquichense total polar archaeolipids:cholesteryl hemisuccinate 4.2:2.8:3 w:w) was tested on different cell lines. Size and HPTS retention of ApH and conventional LpH (dioleylphosphatidylethanolamine:cholesteryl hemisuccinate 7:3 w:w) before and after nebulization were determined. Results & conclusion: DP-ApH suppressed IL-6 and TNF-α on phagocytic cells. Nebulized after 6-month storage, LpH increased size and completely lost its HPTS while ApH3 conserved size and polydispersity, fully retaining its original HPTS content.Fil: Altube, MarĂa Julia. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Selzer, Solange Mailen. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; ArgentinaFil: de Farias, Marcelo Alexandre. Brazilian Nanotechnology National Laboratory; BrasilFil: Portugal, Rodrigo Villares. Brazilian Nanotechnology National Laboratory; BrasilFil: Morilla, MarĂa JosĂ©. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; ArgentinaFil: Romero, Eder Lilia. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; Argentin
Ultra-small solid archaeolipid nanoparticles for active targeting to macrophages of the inflamed mucosa
Aim: Develop nanoparticulate agents for oral targeted delivery of dexamethasone (Dex) to macrophages of inflamed mucosa. Materials & methods: Solid archaeolipid nanoparticles (SAN-Dex) (compritol/Halorubrum tebenquichense polar archaeolipids/soybean phosphatidylcholine/Tween-80 4; 0.9; 0.3; 3% w/w) loaded with Dex were prepared. Their mucopenetration, stability under digestion and in vitro anti-inflammatory activity, were determined. Results: Ultra-small SAN-Dex strongly reduced the levels of TNF-α, IL-6 and IL-12 on J774A1 cells stimulated with lipopolysaccharides as compared with free Dex or loaded in ordinary solid lipid nanoparticles-Dex. After in vitro digestion, the anti-inflammatory activity of SAN-Dex was retained, while that of solid lipid nanoparticles-Dex was lost. Conclusion: Because of their structural and pharmacodynamic features, SAN-Dex may be suitable for oral targeted delivery to inflamed mucosa.Fil: Higa, Leticia Herminia. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Jerez, Horacio Emanuel. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: de Farias, Marcelo Alexandre. Brazilian Nanotechnology National Laboratory; BrasilFil: Portugal, Rodrigo Villares. Brazilian Nanotechnology National Laboratory; BrasilFil: Romero, Eder Lilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; ArgentinaFil: Morilla, MarĂa JosĂ©. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentin
Novel imiquimod nanovesicles for topical vaccination
Development of needle and pain free noninvasive immunization procedures is a top priority for public health agencies. In this work the topical adjuvant activity of the immunomodulator imiquimod (IMQ) carried by ultradeformable archaeosomes (UDA 2 ) (nanovesicles containing sn-2,3 ether linked phytanyl saturated archaeolipids) was surveyed and compared with that of ultradeformable liposomes lacking archaeolipids (UDL 2 ) and free IMQ, using the model antigen ovalbumin and a seasonal influenza vaccine in Balb/c mice. UDA 2 (250 ± 94 nm, -26 ± 4 mV Z potential) induced higher IMQ accumulation in human skin and higher production of TNF-α and IL-6 by macrophages and keratinocytes than free IMQ and UDL 2 . Mixed with ovalbumin, UDA 2 was more efficient at generating cellular response, as measured by an increase in serum IgG2a and INF-Îł production by splenocytes, compared with free IMQ and UDL 2 . Moreover, mixed with a seasonal influenza vaccine UDA 2 produced same IgG titers and IgG2a/IgG1 isotypes ratio (â1) than the subcutaneously administered influenza vaccine. Topical UDA 2 however, induced highest stimulation index and INF-Îł levels by splenocytes. UDA 2 might be a promising adjuvant for topical immunization, since it produced cell-biased systemic response with â 13-fold lower IMQ dose than the delivered as the commercial IMQ cream, Aldara.Fil: Caimi, Ayelen Tatiana. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Altube, MarĂa Julia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; ArgentinaFil: de Farias, Marcelo Alexandre. Centro Nacional de Pesquisa Em Energia E Materiais; BrasilFil: Portugal, Rodrigo Villares. Centro Nacional de Pesquisa Em Energia E Materiais; BrasilFil: Perez, Ana Paula. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; ArgentinaFil: Romero, Eder Lilia. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Morilla, MarĂa JosĂ©. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂa; Argentin