Osteogenic effects of simvastatin-loaded mesoporous titania thin films

The use of statins in the field of bone regeneration is under current investigation due to the existing demand for non-toxic anabolic agents capable of enhancing bone formation in cases of substantial loss. Simvastatin, a coenzyme currently prescribed in clinics to inhibit cholesterol biosynthesis, has been proven to promote osteogenic differentiation by stimulating bone formation and inhibiting osteoclasts activity. We present the loading of simvastatin in mesoporous TiO2 thin films toward combining the pro-osteogenic properties of this molecule with the demonstrated bioactivity of titania. TiO2 thin films processing and characterization were carried out, as well as evaluation of MC3T3-E1 pre-osteoblasts viability when directly incubated with different concentrations of simvastatin, followed by the analysis of osteogenic activity promoted by simvastatin upon loading in the thin films. The accessible porosity of 36% quantified on the 95 ± 5 nm thick mesoporous thin films, together with pore diameters of 5.5 nm, necks between pores of 2.8 nm and interpore distances of 12 ± 2 nm allow the loading of the simvastatin molecule, as confirmed by FTIR spectroscopy. Simvastatin was found to promote MC3T3-E1 pre-osteoblasts viability at concentrations ≤0.01 g l−1, with a cytotoxicity threshold of 0.05 g l−1. We additionally found that film loadings with 0.001 g l−1 simvastatin promotes statistically higher MC3T3-E1 pre-osteoblast proliferation whereas a higher concentration of 0.01 g l−1 leads to statistically higher osteogenic activity (ALP synthesis), after 21 days of incubation, as compared to unloaded films. These results demonstrate the potential of simvastatin local administration based on bioactive mesoporous thin films to promote pro-osteogenic properties. By focusing this strategy on the coating of metallic prostheses, the supply of simvastatin to the target tissue can be favored and risks of systemic side effects will be reduced while enhancing the osteointegration of the implants.Fil: Lopez Alvarez, Miriam. Universidad de Vigo; EspañaFil: López Puente, Vanesa. Universidad de Vigo; EspañaFil: Rodriguez Valencia, Cosme. Universidad de Vigo; EspañaFil: Angelome, Paula Cecilia. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Liz Marzan, Luis M. Ikerbasque; EspañaFil: Serra, Julia. Universidad de Vigo; EspañaFil: Pastoriza Santos, Isabel. Universidad de Vigo; EspañaFil: Gonzalez, Pio. Universidad de Vigo; Españ

Portal del empleado

Material del curso del IFIE "Soy profesor novel en la UBU. ¿Y ahora qué?", 28 de noviembre al 5 de diciembre de 202

Plan de Formación del Profesorado Novel (PFPN)

Material del curso del IFIE "Soy profesor novel en la UBU. ¿Y ahora qué?", 28 de noviembre al 5 de diciembre de 202

¿Qué es el IFIE y sus acciones formativas?

Material del curso del IFIE "Soy profesor novel en la UBU. ¿Y ahora qué?", 28 de noviembre al 5 de diciembre de 202

Soy profesor novel en la UBU. ¿Y ahora qué?

Presentación del curso del IFIE "Soy profesor novel en la UBU. ¿Y ahora qué?", 28 de noviembre al 5 de diciembre de 202

Portal de la Investigación

Material del curso del IFIE "Soy profesor novel en la UBU. ¿Y ahora qué?", 28 de noviembre al 5 de diciembre de 202

Biosynthesis of 5-aminolevulic acid in trypanosoma cruzi

Trypanosoma cruzi requires heme-compounds for growing, due to its partially or totally deficient biosynthetic pathway of heme. There are reports that support the functionality of mitochondrial enzymes involved in this pathway, such as 5-aminolevúlico synthetase (ALA-S) and Heme synthetase (Heme-S). T. cruzi genome is known and two homologous genes, Tc00.1047053511899.40 y Tc00.1047053511071.140, were identified by bioinformatic studies. Both of them are candidates to code with high score (50%) for the ALA-S enzyme, responsible for synthesizing ALA from succinyl CoA and glycine. Our hypothesis is that the parasite is able to synthesize ALA (although it cannot be metabolized to heme) and the Tc00.1047053511899.40 y Tc00.1047053511071.140 sequences encodes for a protein with ALA-S activity. Using epimastigotes, we were able to detect and quantify, by spectrophotometric studies and HPLC chromatography, the presence of ALA in the parasite both intra and extracellularly. The mesasurements were made in 30ml of parasite culture which yielded about 608,31 ± 45,20 nmol of ALA. The extracellular content represents 96% of the total synthesized. Such excretion would be avoiding the citotoxicity of ALA since it cannot be metabolized to heme From bioinformatic studies using the Blast, ORF Finder, Mitoprop, Prosite and ClustalW platforms, it was determined that the above genes would code for a mitochondrial protein (98%) which is dependent on pyridoxal phosphate and shown a KBL domain, which is characteristic of enzymes as ALA-S. Both, ALA detection and the computer analysis would support our hypothesis and encourages us to continue trying to confirm it.Fil: Puente, Vanesa Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Investigaciones sobre Porfirinas y Porfirias. Universidad de Buenos Aires. Centro de Investigaciones sobre Porfirinas y Porfirias; ArgentinaFil: Martinez, Maria del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Investigaciones sobre Porfirinas y Porfirias. Universidad de Buenos Aires. Centro de Investigaciones sobre Porfirinas y Porfirias; ArgentinaFil: Abou Assali, Lubna. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Investigaciones sobre Porfirinas y Porfirias. Universidad de Buenos Aires. Centro de Investigaciones sobre Porfirinas y Porfirias; ArgentinaFil: Benlolo, Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Investigaciones sobre Porfirinas y Porfirias. Universidad de Buenos Aires. Centro de Investigaciones sobre Porfirinas y Porfirias; ArgentinaFil: Bontempi, Esteban. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbrán"; ArgentinaFil: Lombardo, Maria Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Investigaciones sobre Porfirinas y Porfirias. Universidad de Buenos Aires. Centro de Investigaciones sobre Porfirinas y Porfirias; ArgentinaLXIV Reunión Anual de la Sociedad Argentina de Investigación Clínica; LI Reunión Anual de la Asociación Argentina de Farmacología Experimental; XXI Reunión Anual de la Sociedad Argentina de Biología; XXXI Reunión Anual de la Sociedad Argentina de Protozoología; IX Reunión Anual de la Asociación Argentina de Nanomedicinas y VI Reunión Científica Regional de la Asociación Argentina de Ciencia y Tecnología de Animales de LaboratorioMar del PlataArgentinaSociedad Argentina de Investigación ClínicaAsociación Argentina de Farmacología ExperimentalSociedad Argentina de BiologíaSociedad Argentina de ProtozoologíaAsociación Argentina de NanomedicinasAsociación Argentina de Ciencia y Tecnología de Animales de Laboratori

Using Surface Enhanced Raman Scattering to Analyze the Interactions of Protein Receptors with Bacterial Quorum Sensing Modulators

Many members of the LuxR family of quorum sensing (QS) transcriptional activators, including LasR of Pseudomonas aeruginosa, are believed to require appropriate acyl-homoserine lactone (acyl-HSL) ligands to fold into an active conformation. The failure to purify ligand-free LuxR homologues in nonaggregated form at the high concentrations required for their structural characterization has limited the understanding of the mechanisms by which QS receptors are activated. Surface-enhanced Raman scattering (SERS) is a vibrational spectroscopy technique that can be applied to study proteins at extremely low concentrations in their active state. The high sensitivity of SERS has allowed us to detect molecular interactions between the ligand-binding domain of LasR (LasRLBD) as a soluble apoprotein and modulators of P. aeruginosa QS. We found that QS activators and inhibitors produce differential SERS fingerprints in LasRLBD, and in combination with molecular docking analysis provide insight into the relevant interaction mechanism. This study reveals signal-specific structural changes in LasR upon ligand binding, thereby confirming the applicability of SERS to analyze ligand-induced conformational changes in proteinsS

Primary targets of the sesquiterpene lactone deoxymikanolide on Trypanosoma cruzi

Background: Deoxymikanolide is a sesquiterpene lactone isolated from Mikania micrantha and M. variifolia which, has previously demonstrated in vitro activity on Trypanosoma cruzi and in vivo activity on an infected mouse model. Purpose: Based on these promising findings, the aim of this study was to investigate the mechanism of action of this compound on different parasite targets. Methods: The interaction of deoxymikanolide with hemin was examined under reducing and non- reducing conditions by measuring modifications in the Soret absorption band of hemin; the thiol interaction was determined spectrophotometrically through its reaction with 5,5′-dithiobis-2-nitrobenzoate in the presence of glutathione; activity on the parasite antioxidant system was evaluated by measuring the activity of the superoxide dismutase and trypanothione reductase enzymes, together with the intracellular oxidative state by flow cytometry. Superoxide dismutase and trypanothione reductase activities were spectrophotometrically tested. Cell viability, phosphatidylserine exposure and mitochondrial membrane potential were assessed by means of propidium iodide, annexin-V and rhodamine 123 staining, respectively; sterols were qualitatively and quantitatively tested by TLC; ultrastructural changes were analyzed by transmission electron microscopy. Autophagic cells were detected by staining with monodansylcadaverine. Results: Deoxymikanolide decreased the number of reduced thiol groups within the parasites, which led to their subsequent vulnerability to oxidative stress. Treatment of the parasites with the compound produced a depolarization of the mitochondrial membrane even though the plasma membrane permeabilization was not affected. Deoxymikanolide did not affect the intracellular redox state and so the mitochondrial dysfunction produced by this compound could not be attributed to ROS generation. The antioxidant defense system was affected by deoxymikanolide at twenty four hours of treatment, when both an increased oxidative stress and decreased activity of superoxide dismutase and trypanothione reductase (40 and 60% respectively) were observed. Both the oxidative stress and mitochondrial dysfunction induce parasite death by apoptosis and autophagy. Conclusion: Based on our results, deoxymikanolide would exert its anti-T cruzi activity as a strong thiol blocking agent and by producing mitochondrial dysfunction.Fil: Puente, Vanesa Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Investigaciones sobre Porfirinas y Porfirias. Universidad de Buenos Aires. Centro de Investigaciones sobre Porfirinas y Porfirias; ArgentinaFil: Laurella, Laura Cecilia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología. Cátedra de Farmacognosia; ArgentinaFil: Spina Zapata, Renata María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Lozano, Esteban Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Martino, Virginia Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Sosa Escudero, Miguel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Sülsen, Valeria Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Lombardo, Maria Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Investigaciones sobre Porfirinas y Porfirias. Universidad de Buenos Aires. Centro de Investigaciones sobre Porfirinas y Porfirias; Argentin

Patents, supply of medicines and protection of public health

INTRODUCCIÓN: A fin de cumplir con las obligaciones asumidas en la Organización Mundial del Comercio, Argentina comenzó a conceder patentes sobre medicamentos en octubre de 2000. Cerca de 1.000 patentes farmacéuticas fueron concedidas entre 2000 y 2007 OBJETIVOS: caracterizar el patentamiento farmacéutico y, en particular, establecer el tipo de materias protegidas, las aplicaciones terapéuticas y el origen de los titulares de patentes otorgadas; examinar el posible impacto del nuevo régimen de patentamiento sobre las adquisiciones públicas de medicamentos; clarificar en qué situaciones y con qué procedimientos pueden otorgarse licencias obligatorias, especialmente en casos de emergencia sanitaria; y examinar qué implicaciones tiene el marco legal nacional e internacional de la propiedad intelectual sobre las políticas de salud pública. MÉTODOS: Se diseñó y analizó una base de datos con las patentes concedidas en el período indicado. Se revisaron los procedimientos de adquisición de medicamentos del Ministerio de Salud de la Nación y el marco legal aplicable, así como las negociaciones internacionales en curso. RESULTADOS: casi la totalidad de las patentes otorgadas pertenecen a empresas extranjeras; la mayoría se refiere a enfermedades del sistema nervioso e incluyen reivindicaciones del tipo "Markush". La mayoría de las patentes son de derivados o variantes de productos existentes (sales, formulaciones, polimorfos, etc.). CONCLUSIONES: El estudio concluye con recomendaciones, sobre los procedimientos de adquisición, concesión de licencias obligatorias y la transparencia del sistema de patentes en lo concerniente a medicamentos.INTRODUCTION: In order to comply with its obligations in the World Trade Organization, Argentina started to grant patents on pharmaceutical products in October 2000. In the period 2000-2007 near one thousand pharmaceutical patents were granted. OBJECTIVES: To characterize pharmaceutical patenting and, in particular, to establish the type of protected subject matter, the therapeutic uses and the origin of patent owners; to examine the possible impact of the new patenting regime on public procurement of medicines; to clarify in which situations and with which procedures compulsory licenses can be granted, particularly in cases of health emergencies; to examine the implications of the national and international legal framework of intellectual property on public health policies. METHODS: A data base with the patents granted in the above-mentioned period was designed and analyzed, the procurement procedures of the National Ministry of Health were studied, as well as the applicable legal framework and ongoing international negotiations. RESULTS: The study revealed that almost all granted patents belong to foreign companies. The majority refers to diseases of the nervous system and includes 'Markush-type'. In addition, the great majority of patents relate to derivatives or variants of existing products (salts, formulations, polymorphs, etc.). CONCLUSIONS: The study concludes with recommendations, about procurement procedures, the grant of compulsory licenses and the transparency of the patent system as regards medicines.Facultad de Ciencias Médica