5,460 research outputs found

    Phase state and surface topography of palmitoyl-ceramide monolayers

    Get PDF
    In cell biology (and in many biophysical) studies there is a natural tendency to consider ceramide as a highly condensed, solid-type lipid conferring rigidity and close packing to biomembranes. In the present work we advanced the understanding of the phase behavior of palmitoyl-ceramide restricted to a planar interface using Langmuir monolayers under strictly controlled and known surface packing conditions. Surface pressure-molecular area isotherms were complemented with molecular area-temperature isobars and with observations of the surface topography by Brewster Angle Microscopy. The results described herein indicate that palmitoyl-ceramide can exhibit expanded, as well as condensed phase states. Formation of three phases was found, depending on the surface pressure and temperature: a solid (1.80nm thick), a liquid-condensed (1.73nm thick, likely tilted) and a liquid-expanded (1.54nm thick) phase over the temperature range 5-62 °C. A large hysteretic behavior is observed for the S phase monolayer that may indicate high resistance to domain boundary deformation. A second (or higher) order S→LC phase transition is observed at about room temperature while a first order LC→LE transition occurs in a range of temperature encompassing the physiological one (observed above 30 °C at low surface pressure). This phase behavior broadens the view of ceramide as a type of lipid not-always-rigid but able to exhibit polymorphic properties.Fil: Fanani, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; ArgentinaFil: Maggio, Bruno. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; Argentin

    Stability Studies of the Vaccine Adjuvant U-Omp19

    Get PDF
    Unlipidated outer membrane protein 19 (U-Omp19) is a novel mucosal adjuvant in preclinical development to be used in vaccine formulations. U-Omp19 holds two main properties, it is capable of inhibiting gastrointestinal and lysosomal peptidases, increasing the amount of co-administered antigen that reaches the immune inductive sites and its half-life inside cells, and it is able to stimulate antigen presenting cells in vivo. These activities enable U-Omp19 to enhance the adaptive immune response to co-administrated antigens. To characterize the stability of U-Omp19 we have performed an extensive analysis of its physicochemical and biological properties in a 3-year long-term stability study, and under potentially damaging freeze-thawing and lyophilization stress processes. Results revealed that U-Omp19 retains its full protease inhibitor activity, its monomeric state and its secondary structure even when stored in solution for 36 months or after multiple freeze-thawing cycles. Non-enzymatic hydrolysis resulted the major degradation pathway for storage in solution at 4 °C or room temperature which can be abrogated by lyophilization yet increasing protein tendency to form aggregates. This information will play a key role in the development of a stable formulation of U-Omp19, allowing an extended shelf-life during manufacturing, storage, and shipping of a future vaccine containing this pioneering adjuvant.Fil: Darriba, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Cerutti, Maria Laura. Universidad Nacional de San Martin. Centro de Rediseño E Ingenieria de Proteinas.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Bruno, Laura Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Cassataro, Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Pasquevich, Karina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; Argentin

    Ordered-disordered domain coexistence in ternary lipid monolayers activates sphingomyelinase by clearing ceramide from the active phase

    Get PDF
    We explored the action of sphingomyelinase (SMase) on ternary monolayers containing phosphatidylcholine, sphingomyelin (SM) and dihydrocholesterol, which varied along a single tie line of phase coexistence. SMase activity exhibited a higher rate and extent of hydrolysis when the film is within the liquid-expanded (LE)/liquid-ordered (LO) coexistence range, compared to monolayers in the full LO phase. Since Alexa-SMase preferably adsorbs to the LE phase and there was no direct correlation found between enzymatic activity and domain borders, we postulate that the LE phase is the active phase for ceramide (Cer) generation. The enzymatically generated Cer was organized in different ways depending on the initial LE/LO ratio. The action of SMase in Chol-poor monolayers led to the formation of Cer-enriched domains, while in Chol-rich monolayers it resulted in the incorporation of Cer in the LO phase and the formation of new Chol- and Cer-enriched domains. The following novel mechanism is proposed to provide an explanation for the favored action of SMase on interfaces that exhibit an LE-LO phase coexistence: the LO phase sequesters the product Cer causing its depletion from the more enzyme-susceptible LE phase, thus decreasing inhibition by the reaction product. Furthermore, LO domains function as a substrate reservoir by allowing a rapid exchange of the substrate from this phase to the SM-depleted LE phase.Fil: Ale, Elisa Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; ArgentinaFil: Maggio, Bruno. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Fanani, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; Argentin

    Membrane protein remodeling in microglia exposed to amyloid peptides

    Get PDF
    Infection, neurodegeneration, and other conditions associated with loss of brain homeostasis, induce changes in microglial morphology, gene expression and function, generally referred to as “activation”. Alzheimer’s disease (AD) is the most common dementia and is characterized by neuroinfammatory changes, including alterations in the morphology and distribution of microglia and astrocytes, and deposition of complement and other infammatory mediators. Our previous observations show that microglial cells challenged in vitro with amyloid peptides clustered and rounded up, dramatically changing their morphology. Besides, in these cells we observed the early acetylation and then the phosphorylation of STAT3 which is required for the expression of the epsilon isoform of 14-3-3, a marker of Abeta-activated microglia (1, 2). We applied afnity partitioning approach combined with high throughput mass spectrometric analysis in order to identify variation of proteins on plasma membrane of BV2 immortalized microglia upon treatment with amyloid peptides. By this method several proteins up- or down-regulated by amyloid treatment were identifed in microglial plasma membrane. Among them annexins (5 and 7), IFITM3 and MARK3. These data have been confrmed in primary microglial cultures. In microglia, plasma membrane plays a relevant role in the cross-talking with the external neuronal environment and in the resulting trophic or infammatory response of these sentinel cells. As such, knowledge of the microglia responsiveness to beta amyloids in term of changes in its plasma membrane proteome is imperative for unveiling the molecular landscape in which AD occurs

    Do Non-Aromatic Labiatae Produce Essential Oil? The Case Study of Prasium Majus L

    Get PDF
    Prasium majus L. (Labiatae, Lamioideae) is considered a typical non-aromatic plant. In this work we examined the glandular trichomes present on leaves and inflorescences and the essential oils of plants growing along the Tuscan coast of Italy. The micromorphological study evidenced different types of trichomes responsible for the essential oil production. The essential oil compositions of leaves and flowers were analyzed by GC/MS and are here reported

    TCD4pos lymphocytosis in rheumatoid and psoriatic arthritis patients following TNFα blocking agents

    Get PDF
    BACKGROUND: Lymphocyte expansion and true lymphocytosis are commonly observed in the everyday clinical practice. The meaning of such phenomenon is often poorly understood so that discrimination between benign and malignant lymphocytosis remains difficult to establish. This is mainly true when lymphocytosis rises in patients affected by immune-mediated chronic inflammatory diseases under immunosuppressive treatment, conditions potentially associated with lymphomagenesis. In this brief report the development of mild T CD4pos lymphocytosis in a group of patients with chronic arthritis under anti-TNF-α treatment is described. METHODS: Two hundred eight rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients have been evaluated longitudinally for at least 1-year before and 2-years after anti-TNF-α therapy introduction for the possible appearance of a lymphocyte expansion. In patients who developed lymphocyte expansion, T, B and NK cells were analysed. RESULTS: Twenty-five out of 208 (12%) subjects developed a mild T CD4pos lymphocytosis, during anti-TNF-α therapy, which reverted after its interruption. Higher lymphocyte count, more frequent use of steroids and shorter disease duration, before biological therapy start, have emerged as risk factors for lymphocytosis development. CONCLUSIONS: This is the first longitudinal cohort study evaluating the onset of lymphocytosis in RA and PsA patients under anti-TNF-α treatment and its possible clinical relevance. A mild T CD4pos lymphocytosis has been observed in 12% of RA and PsA patients probably related to anti-TNF-α treatment as previously reported by anecdotal cases. Patients with higher baseline lymphocyte count, use of steroids and shorter disease duration before the introduction of biologic therapy, seem to be prone to develop this laboratory reversible abnormality

    Estrategias de agregado de valor territorial: experiencia de bioeconomía circular en Balcarce, Argentina = Territorial Add Value Strategies: Circular Bioeconomy Experiences from Balcarce (Argentina)

    Get PDF
    La preocupación creciente por el incremento de la población mundial, el aumento de la demanda de alimentos y energía, así como por el cambio climático, genera la emergencia de iniciativas de agregado de valor vinculadas al desarrollo de territorios sustentables. El presente artículo se propone analizar el concepto de agregado de valor, y específicamente el agregado de valor territorial, a partir de una experiencia en torno a la bioeconomía circular en el municipio de Balcarce, Buenos Aires, Argentina. Se trata de una empresa innovadora orientada a la cría de insectos a partir de residuos orgánicos, obteniendo proteínas para la alimentación animal y abono. Bajo la metodología de estudio de caso revisamos fuentes secundarias y primarias, y analizamos el conjunto de actividades desarrolladas y coordinadas por la firma. Esta empresa muestra altas potencialidades en generar agregado de valor territorial con cuidado del medioambiente, para lo cual muestra un elevado desarrollo de construcción de redes multiescalares y multidimensionales, articulado entre modelos antagónicos para el desarrollo a nivel local.The growing concern about world population increases, high demand for food and energy, as well as climate change, generates the emergence of value-added initiatives linked to the development of sustainable territories. This article aims to analyze the add value concept, and specifically the territorial add value, based on an experience around the circular bioeconomy in Balcarce, Buenos Aires, Argentina. It is an innovative firm oriented to insect breeding from organic waste, obtaining proteins for animal feed and compost. Under the case study methodology, secondary and primary sources were reviewed, and activities developed and coordinated by the firm were analyzed. This firm shows high potential in generating strategies for territorial add value in a sustainable way. Besides, it shows a high development of multiscale and multidimensional networks, articulating between antagonistic models at local level.EEA BalcarceFil: Bruno, Mariana Paola. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; Argentina.Fil: Bruno, Mariana Paola. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Cendón, María Laura. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; Argentina.Fil: Fil: Cendón, María Laura. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Viteri, Maria Laura. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; Argentina

    Rediseño de la asignatura Mecánica I para su impertición en modalidad b-learning.

    Get PDF
    Esta experiencia se enmarca dentro del conjunto de Proyectos coordinados de Innovación Educativa de distintas Escuelas de la Universidad Politécnica de Madrid (UPM) cuyo objetivo principal es la generación y adaptación de materiales didácticos para transformar de forma progresiva la docencia a formato semi-presencial o completamente a distancia. Como recursos educativos se han utilizado los Objetos de Aprendizaje (OA). En este trabajo se describe la experiencia en la asignatura de Mecánica I y se muestran algunos de los materiales preparados. También se presenta los resultados académicos alcanzados por los alumnos y la valoración cualitativa que hacen los estudiantes respecto a disponer de objetos digitales de aprendizaje

    Linking family farming to endoparasites implicated in public health: A review of current health discussions

    Get PDF
    Family farming is essential in relation to food security, generation of employment, mitigation of poverty and conservation of biodiversity. Many governments have considered it a sector of indigence and degradation, adopting an agro-export model, which contributed to deepening inequality. Since 2000 decade, many countries started to include family farmers in their agenda. Only a few surveys have linked family farming to endoparasites, including zoonotic species. The aim of this paper was to review the records available of helminths, focusing on those with sanitary implication, and the protozoa Toxoplasma gondii, Neospora caninum and Cryptosporidium spp. Collection of data based upon literature available. Helminths with sanitary risk recorded were Ascaris spp., Capillaria spp., Enterobius vermicularis, Fasciola spp., Hymenolepis spp., Schistosoma spp., Taenia spp., Toxocara spp. and Trichuris spp., with prevalence values 0.1 to 95.8%. Three protozoa taxa were recorded, with prevalence values 1.4 to 70%. There is a common concern regarding the sanitary conditions that prevail in family farming system. It is necessary to create the conditions for family farmers to have access to information and education on safe food practices. Governments are called to correct this situation, promoting social integration and economic development, taking into account the particularities of each area.Fil: Fitte, Bruno. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Epizootiología y Salud Pública. Laboratorio de Inmunoparasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Basset, Carina Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Epizootiología y Salud Pública. Laboratorio de Inmunoparasitología; ArgentinaFil: Gos, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Epizootiología y Salud Pública. Laboratorio de Inmunoparasitología; ArgentinaFil: Robles, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Unzaga, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Epizootiología y Salud Pública. Laboratorio de Inmunoparasitología; Argentin

    Long-Term Use of Temozolomide as Safe and Effective Therapy for an Aggressive Corticotroph Adenoma in a Very Old Patient

    Get PDF
    Background: Temozolomide (TMZ) is safe and effective in the treatment of aggressive pituitary adenomas (PAs). However, the optimal duration of TMZ therapy is still unknown. Moreover, data about administration of TMZ in elderly (≥65 years) people to treat aggressive PAs are scarce. We report the case of the oldest female patient undergoing the longest TMZ protocol described so far to treat an aggressive, initially silent corticotroph PA. Case report: The patient initially underwent partial surgical removal of the PA. Subsequent treatment with cabergoline was applied, but it was unsuccessful in controlling the growth of the residual tumor. Pasireotide and external radiation also showed to be ineffective; therefore, treatment with TMZ was started at the standard dose of 200 mg/m2/day for 5 days every 4 weeks for a total of 47 cycles. At the time of treatment's beginning, the patient was 83 years old. Radiological follow-up documented a progressive, remarkable reduction of the adenoma and the last imaging, after 39 cycles of TMZ, showed an intrasellar lesion with large areas of cystic degeneration. The patient also developed adrenal deficiency managed with glucocorticoid replacement. No major side effects were observed throughout the treatment, with exception of nausea, well controlled with anti-emetic medication. TMZ therapy was discontinued after 47 cycles; hormonal and imaging follow-up investigations documented sustained functional and dimensional response. Conclusions: Our case supports the long-term use of TMZ, confirming its safety and efficacy also for elderly patients
    corecore