Biobased polymers derived from itaconic acid bearing clickable groups with potent antibacterial activity and negligible hemolytic activity.

Herein, we report, for the first time, the synthesis of clickable polymers derived from biobased itaconic acid, which was then used for the preparation of novel cationic polymers with antibacterial properties and low hemotoxicity via click chemistry. Itaconic acid (IA) was subjected to chemical modification by incorporating clickable alkyne groups on the carboxylic acids. The resulting monomer with pendant alkyne groups was easily polymerized and copolymerized with dimethyl itaconate (DMI) by radical polymerization. The feed molar ratio of comonomers was varied to precisely tune the content of alkyne groups in the copolymers and the amphiphilic balance. Subsequently, an azide with a thiazole group, which is a component of the vitamin thiamine (B1), was attached onto the polymers by copper-catalyzed azidealkyne cycloaddition (CuAAC) click chemistry leading to triazole linkages. N-Alkylation reactions of the thiazole and triazole groups with methyl and butyl iodides provide the corresponding itaconate derivatives with pendant azolium groups. The copolymers with variable cationic charge densities and hydrophobic/ hydrophilic balances, depending on the comonomer feed ratio, display potent antibacterial activity against Gram-positive bacteria, whereas the activity was almost null against Gram-negative bacteria. Hemotoxicity assays demonstrated that the copolymers exhibited negligible hemolysis and excellent selectivity, more than 1000-fold, for Gram-positive bacteria over human red blood cells.post-print1945 K

Articulación agroecológica: estrategias para la reconversión a escala territorial

Entre los principales argumentos que pretenden descalificar una agricultura sustentable están sus bajos rendimientos y elevados costos. Además, se argumenta una limitada aplicabilidad (solo a escala de pequeñas fincas). Esta polémica se halla presente en la Cuba actual, urgida de soluciones a corto plazo para la alimentación de toda su población. Por ello, se necesita disponer de estrategias y modelos de desarrollo que respondan a los requerimientos actuales, asumiendo el reto de diseñar una agricultura sostenible sobre bases agroecológicas, productiva y eficiente, aplicable a diferentes condiciones y escalas productivas. Este fue reto del proyecto “Articulación agroecológica; diseño de alternativas sostenibles para la seguridad alimentaria local” promovido por la Asociación Cubana de Técnicos Agrícolas y Forestales (ACTAF) y la ONG Holandesa HIVOS. Esta acción se viene ejecutando desde hace 4 años (2011-2015) en 5 municipios cubanos, con apoyo financiero de la Unión Europea, de la Colaboración Suiza para el Desarrollo (COSUDE) y del Ministerio de la Agricultura de Cuba (MINAG). Se partió de la hipótesis de que el desarrollo agrario sostenible sobre bases agroecológicas tiene que diseñarse y conducirse localmente (escala municipal). Para ello, se planteó como objetivo, “contribuir al incremento y la sostenibilidad de la seguridad alimentaria cubana, facilitando la adopción de alternativas de articulación agroecológica en las estrategias de desarrollo agrario municipal”. Para el logro de este objetivo se planteó la necesidad de crear y fortalecer capacidades locales de desarrollo agrario, a partir de instituciones existentes y en coherencia con los programas oficiales de la agricultura local y los intereses y necesidades sentidas de los agricultores. Se trabajó desde un Equipo de Proyecto apoyado por un Equipo Técnico conformado por especialistas de diferentes entidades científicas y docentes nacionales. A nivel local se conformaron Equipos de Articulación Local (EAL) con integrantes designados por cada municipio. Estos EAL constituyeron el principal ente implementador del proyecto y se concibieron como el germen inicial de lo que debía ser el Equipo Municipal de Desarrollo Agrario de cada territorio. Alrededor de estos EAL se articularon las principales instituciones locales vinculadas a la agricultura y se seleccionó una cooperativa para demostrar la pertinencia de la reconversión agroecológica a escala superior a la pequeña finca. Se pudo comprobar que lograr el involucramiento de decisores importantes de la localidad es del todo imprescindible para un proceso de reconversión agroecológica a escala territorial, pues este debe ser visto como contribuyente al logro de los objetivos de las instituciones locales para la seguridad alimentaria de la población y minimizar la dependencia externa al territorio para el desarrollo de toda la cadena productiva. Disponer de servicios técnicos locales que puedan contribuir con insumos alternativos, asesoría y capacitación, aporta a la reconversión capacidad de contextualización de conocimientos y tradiciones campesinas y establece puentes con instituciones científicas especializadas para su complementación con los avances de la ciencia y la técnica.Eje: B2 Paisajes, territorios y agroecología (Relatos de experiencias)Facultad de Ciencias Agrarias y Forestale

Germination response of common annual and perennial forbs to heat shock and smoke treatments in the Chaco Serrano, central Argentina

Fire is a key ecological factor affecting plant dynamics. In the last few decades, fire occurrence in the Chaco region has increased noticeably, challenging the adaptive capacity of plants to regenerate after a fire. Broad-leaved forb species have been much less studied than woody and graminoids, although they are an important component of fire dynamics. Here we analysed the germination response to heat shock of 70 and 110°C, smoke and their combination in 10 broad-leaved herbaceous species frequently occurring in the Chaco Serrano of Córdoba province, central Argentina, including five annual (Bidens subalternans, Conyza bonariensis, Schkuhria pinnata, Tagetes minuta and Zinnia peruviana) and five perennial species (Borreria eryngioides, Sida rhombifolia, Solidago chilensis, Taraxacum officinale and Verbena litoralis). We also compared the response of annual versus perennial species. Six species had highest germination when treated with heat and smoke combined, whereas two had lowest germination under this treatment, indicating synergistic and antagonistic interaction of these factors respectively. Most of the species tolerated heat shock (i.e. germination was similar to that in control treatment), whereas others had higher germination in response to heat shock, especially under the moderate 70°C treatment. Germination was higher than control (i.e. no heat and no smoke) after smoke treatment in four species. Perennial species showed higher average germination than annuals in both heat treatments and in the control. Annual species had higher average germination for all treatments involving smoke. The high variability observed at the species level, and the limited number of species studied calls for precaution in interpreting and extrapolating results. Nevertheless, our study shows a general positive response of both perennial and annual species to fire cues, suggesting an advantage of these species for colonizing post-fire environments, and being favoured under scenarios of increasingly frequent low-to-medium intensity fires.Fil: Arcamone, Julieta Rocío. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Diversidad Biológica y Ecológica. Cátedra de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Jaureguiberry, Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

Defining the Molecular Basis of Tumor Metabolism: a Continuing Challenge Since Warburg's Discovery

Cancer cells are the product of genetic disorders that alter crucial intracellular signaling pathways associated with the regulation of cell survival, proliferation, differentiation and death mechanisms. the role of oncogene activation and tumor suppressor inhibition in the onset of cancer is well established. Traditional antitumor therapies target specific molecules, the action/expression of which is altered in cancer cells. However, since the physiology of normal cells involves the same signaling pathways that are disturbed in cancer cells, targeted therapies have to deal with side effects and multidrug resistance, the main causes of therapy failure. Since the pioneering work of Otto Warburg, over 80 years ago, the subversion of normal metabolism displayed by cancer cells has been highlighted by many studies. Recently, the study of tumor metabolism has received much attention because metabolic transformation is a crucial cancer hallmark and a direct consequence of disturbances in the activities of oncogenes and tumor suppressors. in this review we discuss tumor metabolism from the molecular perspective of oncogenes, tumor suppressors and protein signaling pathways relevant to metabolic transformation and tumorigenesis. We also identify the principal unanswered questions surrounding this issue and the attempts to relate these to their potential for future cancer treatment. As will be made clear, tumor metabolism is still only partly understood and the metabolic aspects of transformation constitute a major challenge for science. Nevertheless, cancer metabolism can be exploited to devise novel avenues for the rational treatment of this disease. Copyright (C) 2011 S. Karger AG, BaselFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Univ Fed ABC UFABC, CCNH, Santo Andre, BrazilUniversidade Federal de São Paulo UNIFESP, Dept Ciencias Biol, São Paulo, BrazilUniversidade Federal de São Paulo UNIFESP, Dept Bioquim, São Paulo, BrazilUniv Fed Sao Carlos UFSCar, DFQM, Sorocaba, BrazilUniversidade Federal de São Paulo UNIFESP, Dept Ciencias Biol, São Paulo, BrazilUniversidade Federal de São Paulo UNIFESP, Dept Bioquim, São Paulo, BrazilFAPESP: 10/16050-9FAPESP: 10/11475-1FAPESP: 08/51116-0Web of Scienc

Cognitive frailty: rational and definition from an (I.A.N.A./I.A.G.G.) international consensus group.

The frailty syndrome has recently attracted attention of the scientific community and public health organizations as precursor and contributor of age-related conditions (particularly disability) in older persons. in parallel, dementia and cognitive disorders also represent major healthcare and social priorities. although physical frailty and cognitive impairment have shown to be related in epidemiological studies, their pathophysiological mechanisms have been usually studied separately. an international Consensus Group on “Cognitive Frailty” was organized by the international academy on nutrition and aging (i.a.n.a) and the international association of Gerontology and Geriatrics (i.a.G.G) on april 16th, 2013 in toulouse (France). the present report describes the results of the Consensus Group and provides the first definition of a “Cognitive Frailty” condition in older adults. specific aim of this approach was to facilitate the design of future personalized preventive interventions in older persons. Finally, the Group discussed the use of multidomain interventions focused on the physical, nutritional, cognitive and psychological domains for improving the well-being and quality of life in the elderly. the consensus panel proposed the identification of the so-called “cognitive frailty” as an heterogeneous clinical manifestation characterized by the simultaneous presence of both physical frailty and cognitive impairment. in particular, the key factors defining such a condition include: 1) presence of physical frailty and cognitive impairment (Cdr=0.5); and 2) exclusion of concurrent ad dementia or other dementias. under different circumstances, cognitive frailty may represent a precursor of neurodegenerative processes. a potential for reversibility may also characterize this entity. a psychological component of the condition is evident and concurs at increasing the vulnerability of the individual to stressors

Abundancia de sifonóforos y larvas de Sardinops sagax caerulea en el invierno (1981-1982), en Bahía Magdalena B.C.S. México

Se encontraron ocho especies de Sifonóforos en muestras de plancton colectadas en diciembre de 1981; enero, febrero y marzo de 1982, dentro del complejo lagunar Bahía Magdalena y Bahía Almejas, Baja California Sur. Las especies más abundantes fueron: Muggiaea atlantica en su fase poligástríca, que presentó valores acumulados mayores a 7500/100 m, durante enero. La fase eudoxia con función reproductiva, Diphyosis mitra y Chelophyes contorta presentó valores acumulados de 5000/100 m durante el mismo mes. Se encontro una correlación negativa entre la abundancia de lar vas de Sardinops sagax caerulea y la fase poligástrica de Muggiaea atlantica encontrándose un coeficiente de correlación de -0.92