Marine nematode taxonomy in the DNA age: the present and future of molecular tools to access their biodiversity

Molecular taxonomy is one of the most promising yet challenging fields of biology. Molecular markers such as nuclear and mitochondrial genes are being used in a variety of studies surveying marine nematode taxa. Sequences from more than 600 species have been deposited to date in online databases. These barcode sequences are assigned to 150 nominal species from 104 genera. There are 41 species assigned to Enoplea and 109 species to Chromadorea. Morphology-based surveys are greatly limited by processing speed, while barcoding approaches for nematodes are hampered by difficulties in matching sequence data with morphology-based taxonomy. DNA barcoding is a promising approach because some genes contain variable regions that are useful to discriminate species boundaries, discover cryptic species, quantify biodiversity and analyse phylogeny. We advocate a combination of several approaches in studies of molecular taxonomy, DNA barcoding and conventional taxonomy as a necessary step to enhance the knowledge of biodiversity of marine nematodes

Biological activity of phenolic compounds from argentinean herbs infusions

Argentinean herbal infusions were studied for their beneficial biological properties and secondary metabolites content, such as phenolic compounds in order to find new natural products beneficial. The modifications of antihypertensive and antioxidant activities by the addition of commonly used additives (lemon, sugar and sweetener) were studied also. Ilex paraguaiensis infusion showed the highest concentration of phenolic compounds and flavonoid fraction, the supplementation with lemon juice increased the phenolic compound content. All infusion showed high DPPH radical scavenging assays and additives did not modify significantly this activity. The infusion of I. paraguaiensis presents the maximum viability reduction of Escherichia coli and Staphylococcus aureus and the herbs combination Lippia integrifolia-Ilex paraguaiensis was the most effective to reduce S. aureus and E.coli viability. The phenolic compounds concentration as well as the qualitative composition of each infusion plays an important role in the antimicrobial activity. Because the high correlation between the concentration of total phenolic compounds and antioxidant and antihypertensive activities, we can infer that the phenolic compounds are responsible for such activities. The results obtained allow us to propose the herbs studied as potential natural antioxidants and antihypertensive compounds that could be used in pharmaceutical and food industries.Fil: Rodriguez Vaquero, Maria Jose. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vallejo, Claudia Veronica. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aredes Fernández, Pedro Adrián. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Marine nematode taxonomy in the DNA age: the present and future of molecular tools to access their biodiversity

Molecular taxonomy is one of the most promising yet challenging fields of biology. Molecular markers such as nuclear and mitochondrial genes are being used in a variety of studies surveying marine nematode taxa. Sequences from more than 600 species have been deposited to date in online databases. These barcode sequences are assigned to 150 nominal species from 104 genera. There are 41 species assigned to Enoplea and 109 species to Chromadorea. Morphology-based surveys are greatly limited by processing speed, while barcoding approaches for nematodes are hampered by difficulties in matching sequence data with morphology-based taxonomy. DNA barcoding is a promising approach because some genes contain variable regions that are useful to discriminate species boundaries, discover cryptic species, quantify biodiversity and analyse phylogeny. We advocate a combination of several approaches in studies of molecular taxonomy, DNA barcoding and conventional taxonomy as a necessary step to enhance the knowledge of biodiversity of marine nematodes

Promoter sequence of Shiga Toxin II (Stx2) is recognized in vivo leading to the production of biologically active Stx2

Shiga toxins (Stxs) are the main agent responsible for the development of hemolytic uremic syndrome (HUS), the most severe and life-threatening systemic complication of infection with enterohemorrhagic Escherichia coli (EHEC) strains. We previously reported Stx2 expression by eukaryotic cells after they were transfected in vitro with the stx2 gene cloned into a prokaryotic plasmid (pStx2). The aim of this study was to evaluate whether mammalian cells were also able to express Stx2 in vivo after pStx2 injection. Mice were inoculated by hydrodynamic based transfection (HBT) with pStx2. We studied the survival, the percentage of polymorphonuclear leukocytes in plasma, plasma urea levels and histology of the kidney and the brain of mice. Mice displayed a lethal dose-response to pStx2. Stx2-mRNA was recovered from the liver and Stx2 cytotoxic activity was observed in plasma of mice injected with pStx2. Stx2 was detected by immunofluorescence in the brains of mice inoculated with pStx2, and markers of central nervous system (CNS) damage were observed, including increased expression of glial fibrillary acidic protein (GFAP) and fragmentation of NeuN in neurons. Moreover, anti-Stx2B immunized mice were protected against pStx2 inoculation. Our results show that Stx2 is expressed in vivo from the wild stx2 gene, reproducing pathogenic damage induced by purified Stx2 or secondary to EHEC-infection.Fil: Bentancor, Leticia Veronica. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental; ArgentinaFil: Mejias, Maria Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental; ArgentinaFil: Pinto, Alípio. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas; ArgentinaFil: Bilen, Marcos Fabian. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular; ArgentinaFil: Meiss, Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental; ArgentinaFil: Rodriguez Galan, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Baez, Natalia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Pedrotti, Luciano Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Goldstein Raij, Jorge. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas. Laboratorio de Fisiopatogenia; ArgentinaFil: Ghiringhelli, Pablo Daniel. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular; ArgentinaFil: Palermo, Marina Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; Argentin

Industrial manufacturing and characterization of multiscale CFRP laminates made from prepregs containing graphene-related materials

The introduction of graphene-related materials (GRMs) in carbon fibre-reinforced polymers (CFRP) has been proved to enhance their mechanical and electrical properties. However, methodologies to produce the 3-phase materials (multiscale composites) at an industrial scale and in an efficient manner are still lacking. In this paper, multiscale CFRP composites containing different GRMs have been manufactured following standard procedures currently used in the aerospace industry with the aim to evaluate its potential application. Graphite nanoplateletelets (GNPs), in situ exfoliated graphene oxide (GO) and reduced graphene oxide (rGO) have been dispersed into an epoxy resin to subsequently impregnate aeronautical grade carbon fibre tape. The resulting prepregs have been used for manufacturing laminates by hand lay-up and autoclave curing at 180 {\deg}C. Abroad characterization campaign has been carried out to understand the behaviour of the different multiscale laminates manufactured. The degree of cure, glass transition temperature and degradation temperature have been evaluated by thermal evolution techniques. Similarly, their mechanical properties (tensile, flexural, in-plane shear, interlaminar shear and mode I interlaminar fracture toughness) have been analysed together with their electrical conductivity. The manufacturing process resulted appropriated for producing three-phase laminates and their quality was as good as in conventional CFRPs. The addition ofGOand rGO resulted in an enhancement of the in-plane shear properties and delamination resistance while the addition ofGNPimproved the electrical conductivity

Transformaciones territoriales y desigualdad en el norte de la Patagonia: extractivismo y conflictos en las zonas agrarias y turísticas.

En este artículo presentamos estudios en curso que abordan las transformaciones territoriales en las zonas agrarias y turísticas del norte de la Patagonia, a partir de las cuales se profundiza la profundización de los procesos de expropiación y desigualdad. Consideramos que las dinámicas analizadas se observan como expropiación de bienes comunes como la tierra y el agua. A partir del trabajo de campo realizado en los valles de regadío de los ríos Negro y Neuquén y en las zonas de estepa y cordillera de la provincia de Neuquén, pretendemos atender las nuevas dinámicas de control de la naturaleza y dar cuenta de las resistencias territorializadas que se expresan a través de diversas acciones. en respuesta a las expropiaciones ejercidas por el frente extractivo.In this paper we present ongoing studies that address territorial transformations in agrarian and tourist areas of northern Patagonia, from which to problematize the deepening of processes of dispossession and inequality. We consider that the analyzed dynamics are observed as dispossession of common goods such as land and water. From the field work carried out in the irrigated valleys of the Negro and Neuquén rivers and in steppe and cordillera zones in the Neuquén province, we intend to attend to new dynamics of nature control and to account for the territorialized resistances that they are expressed through various collective actions in response to the dispossessions exerted by the extractivist front.Fil: Trpin, Veronica. Universidad Nacional del Comahue. Instituto Patagonico de Estudios en Humanidades y Ciencias Sociales; Argentina.Fil: Trpin, Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Rodriguez, María Daniela. Universidad Nacional del Comahue. Instituto Patagonico de Estudios en Humanidades y Ciencias Sociales; Argentina.Fil: Rodriguez, María Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Inactivation of Listeria monocytogenes and Salmonella Typhimurium in strawberry juice enriched with strawberry polyphenols

BACKGROUND: Low molecular-weight phenolic fractions (LMPFs) were extracted from Albion (LMPF-A) and Camarosa (LMPF-C) strawberry cultivars. Their antibacterial activity against Listeria monocytogenes and Salmonella Typhimurium cocktails in vitro and in vivo was investigated using strawberry juice as a food model. This study also sought to determine their antibacterial mechanism. RESULTS: Quercetin was identified as a principal compound in both phenolic fractions. The minimum bactericide concentration (MBC) values were 750 and 850 μg mL−1 (LMPF-C) and 800 and 950 μg mL−1 (LMPF-A) against S.Typhimurium and L. monocytogenes, respectively. The possible antibacterial activity of the phenolic extracts could be related to the release of phosphate and potassium ions, the effect of the disruption of membrane integrity on L. monocytogenes, and the effect of the inhibition of dihydronicotinamide adenine dinucleotide (NADH) oxidase activity on S. Typhimurium. Quercetin and kaempferol were the most active compounds in producing bacterial damage. Strawberry juice supplemented with the phenolic fractions and incubated at 37, 20, and 4 °C reduced bacterial viability; moreover, after treatment with the phenolic fraction at the lowest temperature, no viable cells were detected after 7 days’ incubation. Salmonella was more sensitive to the supplements than Listeria in strawberry juice. CONCLUSIONS: This study could form the basis for the development of natural antibacterial agents that could be included in natural juice or used by the pharmaceutical industry.Fil: Vallejo, Claudia Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Microbiología General; ArgentinaFil: Minahk, Carlos Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Rollan, Graciela Celestina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Rodriguez Vaquero, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Microbiología "Luis Verna". Cátedra de Microbiología General; Argentin

Programa de Acompañamiento a los Estudios Secundarios : Ensayo de una política de inclusión escolar

In the debate about creating devices (dispositifs) to provide answers to the problems related to the ending of high school studies, we consider the analysis of “Accompanying Programme to Secondary Education” (PACES for its acronym in Spanish), developed in Cordoba between 2015 and 2019. We consider that PACES constitutes a unique study case. It is unique because it lasted a short period of time; and because of its articulated development to another device, still in force, “Programme of Inclusion and Completion of Secondary Education for youngsters between the ages of 14 and 17” (PIT 14-17 for its acronym in Spanish) that aims to aid students whose secondary education continuity is at risk. PACES put to work a syllabus and pedagogical organization to tackle the accreditation of subjects and courses in regular secondary school by means of a “different repetition experience”. This was created to avoid school dropout with the purpose of entering PIT 14-17. This investigation was carried out from a socio-anthropological point of view and from an interpretative approach. This exposition focuses on three main topics: a) origins, functioning and organization of PACES as an inclusive education policy; b) programme design: organizational, pedagogical, didactic and course contents aspects; c) school practices, classroom dynamics and feelings of the people involved in the programme.En la discusión sobre la construcción de dispositivos escolares para dar respuesta a los problemas de finalización de estudios secundarios, se pone a consideración el análisis del “Programa de Acompañamiento en la Continuidad a los Estudios Secundarios (PACES)”, desarrollado en Córdoba entre 2015 y 2019. El PACES constituye un caso único por su duración y su desarrollo articulado a otro dispositivo, aún en vigencia, el “Programa de Inclusión y Terminalidad de la Educación Secundaria para Jóvenes de 14 a 17 años (PIT 14-17)” que todavía tiene como objetivo atender a estudiantes en situación de abandono de los estudios secundarios. El PACES puso en marcha una organización curricular y pedagógica para atender la acreditación de asignaturas en la escuela secundaria común por medio de una “repitencia diferente” y con el propósito de evitar la deserción escolar como posibles pedidos de ingreso al PIT. El trabajo de investigación se realizó desde un enfoque socioantropológico con un abordaje interpretativo. La exposición pone foco en tres ejes: a) orígenes, funcionamiento y organización del PACES en tanto política de inclusión educativa; b) diseño del programa: aspectos organizacionales, pedagógicos, didácticos y curriculares; c) prácticas escolares, dinámica en las aulas y los sentires de los sujetos involucrados

Investigación en matemáticas, economía y ciencias sociales

El resultado de este libro que reune inquietudes académicas en torno a temas tan estudiados como los que están alrededor del maíz, del frijol o del café; y tan contemporáneos como las aplicaciones concretas de las ciencias ya citadas, al estudio de la adopción del comercio electrónico en empresas del sector agroindustrial o, el caso de la generación de biogas o energía eléctrica por medio de biodigestores. Al editar este texto e incorporarlo a la bibliografía de los temas de referencia, se enriquecen opciones de consulta para los estudiosos de esos temas en general; pero también para interesados en aspectos tan específicos como la cadena de suministro del mercado hortofrutícola en Texcoco

Conversion of grape pomace into fungal biomass: a study of Pleurotus cultivation for a sustainable agro-residue management

Background Grape production generates substantial agricultural waste, particularly grape pomace, a by-product rich in bioactive compounds. Moreover, its reuse is strongly recommended to prevent environmental issues from improper disposal. This study explores the feasibility of using exhausted grape pomace, alone and in combination with anaerobic digestate, as substrates for Pleurotus mushroom cultivation. Grape pomace is rich in fiber, lipids, sugars, proteins, and phenolic compounds, which makes it a promising substrate for this purpose.Results Elemental analyses of this substrate revealed high carbon (46%) and nitrogen (2.5%) contents, along with greater levels of macro and microelements (P, Ca, Mg, Fe) compared to conventional substrates. Fourier Transformed Infrared (FTIR) spectroscopy identified aliphatic groups from seed fatty acids and polysaccharide bands, typical of the seedless part of grape pomace. Fatty acid evaluation confirmed the presence of partial glycerides with linoleic acid content exceeding 62%, while phenolic composition analysis highlighted a predominance of bound phenols. These chemical characteristics significantly increased mushroom production, with statistically significant increases in fresh weights observed upon the addition of grape pomace, resulting in variations exceeding 130% in some instances. The mixture with digestate exhibited the most promising results, probably due to improved pH values. FTIR and Surface Enhanced Raman Scattering (SERS) spectra of mushrooms grown on different matrices were similar, but with some differences likely related to substrate composition. In addition, SERS analysis identified ergothioneine, a significant fungal amino acid, which was not detectable in the FTIR spectra. Conclusions This study highlights grape pomace as an effective and sustainable substrate for mushroom cultivation, offering a viable alternative to conventional growth mediums. The high yield and consistent quality of mushrooms grown on grape pomace, particularly when mixed with anaerobic digestate, demonstrate its potential for commercial mushroom production. The findings support the broader goals of sustainable agriculture by promoting the recycling of agricultural by-products, minimizing waste, and adding economic value. This innovative approach to utilizing grape pomace contributes to improved environmental management and opens new opportunities for enhancing the efficiency and sustainability of mushroom cultivation practices