109 research outputs found

    First Evidence of Reproductive Adaptation to “Island Effect” of a Dwarf Cretaceous Romanian Titanosaur, with Embryonic Integument In Ovo

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    <div><h3>Background</h3><p>The Cretaceous vertebrate assemblages of Romania are famous for geographically endemic dwarfed dinosaur taxa. We report the first complete egg clutches of a dwarf lithostrotian titanosaur, from Toteşti, Romania, and its reproductive adaptation to the “island effect”.</p> <h3>Methodology/Findings</h3><p>The egg clutches were discovered in sequential sedimentary layers of the Maastrichtian Sânpetru Formation, Toteşti. The occurrence of 11 homogenous clutches in successive strata suggests philopatry by the same dinosaur species, which laid clutches averaging four ∼12 cm diameters eggs. The eggs and eggshells display numerous characters shared with the positively identified material from egg-bearing level 4 of the Auca Mahuevo (Patagonia, Argentina) nemegtosaurid lithostrotian nesting site. Microscopic embryonic integument with bacterial evidences was recovered in one egg. The millimeter-size embryonic integument displays micron size dermal papillae implying an early embryological stage at the time of death, likely corresponding to early organogenesis before the skeleton formation.</p> <h3>Conclusions/Significance</h3><p>The shared oological characters between the Haţeg specimens and their mainland relatives suggest a highly conservative reproductive template, while the nest decrease in egg numbers per clutch may reflect an adaptive trait to a smaller body size due to the “island effect”. The combined presence of the lithostrotian egg and its embryo in the Early Cretaceous Gobi coupled with the oological similarities between the Haţeg and Auca Mahuevo oological material evidence that several titanosaur species migrated from Gondwana through the Haţeg Island before or during the Aptian/Albian. It also suggests that this island might have had episodic land bridges with the rest of the European archipelago and Asia deep into the Cretaceous.</p> </div

    Cancer-selective, single agent chemoradiosensitising gold nanoparticles

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    Two nanometre gold nanoparticles (AuNPs), bearing sugar moieties and/or thiol-polyethylene glycol-amine (PEG-amine), were synthesised and evaluated for their in vitro toxicity and ability to radiosensitise cells with 220 kV and 6 MV X-rays, using four cell lines representing normal and cancerous skin and breast tissues. Acute 3 h exposure of cells to AuNPs, bearing PEG-amine only or a 50:50 ratio of alpha-galactose derivative and PEG-amine resulted in selective uptake and toxicity towards cancer cells at unprecedentedly low nanomolar concentrations. Chemotoxicity was prevented by co-administration of N-acetyl cysteine antioxidant, or partially prevented by the caspase inhibitor Z-VAD-FMK. In addition to their intrinsic cancer-selective chemotoxicity, these AuNPs acted as radiosensitisers in combination with 220 kV or 6 MV X-rays. The ability of AuNPs bearing simple ligands to act as cancer-selective chemoradiosensitisers at low concentrations is a novel discovery that holds great promise in developing low-cost cancer nanotherapeutics

    Evaluation of the in vitro antimicrobial activity of leaves extracts of different cultivars of Fragaria ananassa Duch. for phytosanitary bioproducts formulation

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    En este trabajo se caracterizaron extractos metanólicos y acuosos de hojas de Fragaria ananassa Duch. de los genotipos “Camarosa”, “Camino Real”, “Merced”, “Benicia” y “San Andreas” (este último de dos procedencias: Tafí del Valle, Tucumán, y Patagonia), en base al contenido de compuestos fenólicos totales y a la capacidad para inhibir el crecimiento de bacterias y hongos fitopatógenos. No se observaron diferencias significativas en el contenido de fenólicos a excepción del extracto metanólico (EM) del genotipo “Merced” que presentó el mayor valor y los extractos acuosos (EA) de los genotipos “San Andreas” de Tafí del Valle y “Camarosa”, que fueron los de menor contenido. Las bacterias mostraron mayor sensibilidad que los hongos a los EM, mientras que en el caso de los EA ambos tipos de microorganismos mostraron una sensibilidad similar. No se observó una relación directa entre el contenido de compuestos fenólicos totales y la actividad antimicrobiana. Aunque algunos genotipos de frutilla mostraron actividad antimicrobiana específica, en general todos los genotipos evaluados presentaron un comportamiento similar. Se destacan los extractos acuosos para el desarrollo de un bioinsumo de bajo costo de producción, aprovechando los residuos de cosecha del cultivo de frutilla.In this work, methanolic and aqueous extracts from leaves of five genotypes of Fragaria ananassa Duch. were characterized based on their total phenolic compounds content and the ability to inhibit the growth of bacterial and fungal phytopathogens. Genotypes studied were: “Camarosa”, “Camino Real”, “Merced”, “Benicia” and “San Andreas” (this last one from two origins: Tafí del Valle, Tucumán and Patagonia). No significant differences were observed in the phenolic content except for the methanolic extract (ME) of the “Merced” genotype that presented the highest value and the aqueous extracts (AE) of the “San Andreas” genotypes from Tafí del Valle and “Camarosa”, which exhibited the lowest value. Bacteria showed greater sensitivity than fungi to ME, whereas in the case of AE both types of microorganisms showed a similar sensitivity. No direct correlation was observed between the content of total phenolic compounds and the antimicrobial activity. Although some strawberry genotypes showed specific antimicrobial activity, in general all evaluated genotypes showed a similar behavior and would be equally valid for the development of bioproducts. The aqueous extracts stand out for the development of bioproducts of low production cost, taking advantage of the crop residues of the strawberry crop.Fil: Cerviño Dowling, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres" (p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Grellet Bournonville, Carlos Froilan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres" (p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Di Peto, Pía de Los Ángeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres" (p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Rodríguez, L. C.. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia. Departamento de Biología; ArgentinaFil: Castagnaro, Atilio Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres" (p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Filippone, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia. Departamento de Biología; ArgentinaFil: Mamani, Alicia Ines de Fatima. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia. Departamento de Biología; Argentin

    Paleobiology of titanosaurs: reproduction, development, histology, pneumaticity, locomotion and neuroanatomy from the South American fossil record

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    Fil: GarcĂ­a, Rodolfo A.. Instituto de InvestigaciĂłn en PaleobiologĂ­a y GeologĂ­a. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Salgado, Leonardo. Instituto de InvestigaciĂłn en PaleobiologĂ­a y GeologĂ­a. General Roca. RĂ­o Negro; ArgentinaFil: FernĂĄndez, Mariela. Inibioma-Centro Regional Universitario Bariloche. Bariloche. RĂ­o Negro; ArgentinaFil: Cerda, Ignacio A.. Instituto de InvestigaciĂłn en PaleobiologĂ­a y GeologĂ­a. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Carabajal, Ariana Paulina. Museo Carmen Funes. Plaza Huincul. NeuquĂŠn; ArgentinaFil: Otero, Alejandro. Museo de La Plata. Universidad Nacional de La Plata; ArgentinaFil: Coria, Rodolfo A.. Instituto de PaleobiologĂ­a y GeologĂ­a. Universidad Nacional de RĂ­o Negro. NeuquĂŠn; ArgentinaFil: Fiorelli, Lucas E.. Centro Regional de Investigaciones CientĂ­ficas y Transferencia TecnolĂłgica. Anillaco. La Rioja; Argentin
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