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What do we know about the publications related with Azospirillum? A metadata analysis

What do we know about the publications related with Azospirillum? A metadata analysis Cassan, Fabricio Dario; Lopez, Gaston Alberto; Nievas, Sofia Mariela; Coniglio, Nayla Anahí; Torres, Daniela Soledad; Donadío, Evelyn Florencia; Molina, Romina Micaela; Mora, Maria Veronica Azospirillum is one of the most successful plant growth-promoting bacteria (PGPB) genera and it is considered a study model for plant–bacteria interactions. Because of that, a wide broad of topics has been boarded and discussed in a significant number of publications in the last four decades. Using the Scopus® database, we conducted a bibliographic search in order to analyze the number and type of publications, the authors responsible of these contributions, and the origin of the researchers, as well as the keywords and journals selected by the authors, among other related characteristics, with the aim to understand some less addressed details about the work done with Azospirillum worldwide since its discovery in 1925. Despite that the largest numbers of publications about this bacterium were obtained between the 1970 and 1980s, there is still a linear increase tendency in the number of published works. Understanding the mechanisms involved in the ability of these bacteria to promote growth in a wide broad of plant species under both laboratory and field conditions has been a preferential target for these published articles. This tendency could be considered a cause or consequence of the current increase in the number of commercial products formulated with Azospirillum around the world and a catalyzer for the increase of published articles along time.

Temporal and spatial variation in the soil seed bank of Nassella trichotoma (serrated tussock) in its native range

Temporal and spatial variation in the soil seed bank of Nassella trichotoma (serrated tussock) in its native range García, Andrés; Loydi, Alejandro; Distel, Roberto Alejandro Serrated tussock (Nassella trichotoma (Nees) Hack. ex Arechav) is an unpalatable grass species that has been expanding in its native range and invading non-native ranges. In this study in its natural environment, we aimed to describe the spatial relationship between seed density, the cover and density of standing individuals of serrated tussock, the seasonal variation in the seed density in the soil seed bank, and to compare these results with those reported in non-native ranges. We took soil samples seasonally and recorded the cover and density of standing individuals of serrated tussock at two sites in the native Pampas grasslands in central-east Argentina. Seed density was evaluated by seedling emergence and seed extraction. Seed density showed a seasonality trend, with maximum values in the end of summer and minimum values in winter and spring. Seed density was independent of the cover and density of standing individuals of serrated tussock. The values of seed density were lower than those reported in the invaded ranges. Since seeds of serrated tussock are present in the seed bank regardless of the cover and density of its standing individuals, the maintenance of a high cover of desirable species may play a key role in preventing the establishment of serrated tussock in both its natural and invaded ranges.

ALD1 accumulation in Arabidopsis epidermal plastids confers local and non-autonomous disease resistance

ALD1 accumulation in Arabidopsis epidermal plastids confers local and non-autonomous disease resistance Jiang, Shang-Chuan; Engle, Nancy L.; Banday, Zeeshan Zahoor; Cecchini, Nicolas Miguel; Jung, Ho Won; Tschaplinski, Timothy J.; Greenberg, Jean T. The Arabidopsis plastid-localized ALD1 protein acts in the lysine catabolic pathway that produces infection-induced pipecolic acid (Pip), Pip derivatives, and basal non-Pip metabolite(s). ALD1 is indispensable for disease resistance associated with Pseudomonas syringae infections of naïve plants as well as those previously immunized by a local infection, a phenomenon called systemic acquired resistance (SAR). Pseudomonas syringae is known to associate with mesophyll as well as epidermal cells. To probe the importance of epidermal cells in conferring bacterial disease resistance, we studied plants in which ALD1 was only detectable in the epidermal cells of specific leaves. Local disease resistance and many features of SAR were restored when ALD1 preferentially accumulated in the epidermal plastids at immunization sites. Interestingly, SAR restoration occurred without appreciable accumulation of Pip or known Pip derivatives in secondary distal leaves. Our findings establish that ALD1 has a non-autonomous effect on pathogen growth and defense activation. We propose that ALD1 is sufficient in the epidermis of the immunized leaves to activate SAR, but basal ALD1 and possibly a non-Pip metabolite(s) are also needed at all infection sites to fully suppress bacterial growth. Thus, epidermal plastids that contain ALD1 play a key role in local and whole-plant immune signaling.

Vine mealybugs disrupt biomass allocation in grapevine

Vine mealybugs disrupt biomass allocation in grapevine Schulze sylvester, Maria; Corronca, Jose Antonio; Paris, Carolina Ivon Vine mealybug Planococcus ficus Signoret (Hemiptera: Pseudococcidae) is an important phloem-feeding pest species in many grapevine producing areas worldwide. The economic damage of P. ficus is thought to be mainly caused by sooty mould on infested grape clusters and transmission of plant viruses. Direct damage caused by mealybug feeding to grapevine plants (Vitis vinifera, L.) has only been vaguely described or otherwise completely discarded. The present study is the first to give an insight into the direct impacts of P. ficus on vegetative growth and biomass dynamics of grapevine plants. In a screenhouse, three-year-old, potted grapevine plants were infested with mealybugs at two different densities, imitating high and low field infestation levels. Mealybug numbers, plant biomass, leaf area, leaf size and leaf number were monitored over six months and compared to a control treatment without mealybugs. High infestation levels reduced leaf and stem biomass by one third, while low levels of P. ficus impacted only stem biomass, indicating a higher sensibility of the perennial parts of the plant or a reallocation of biomass. Leaf area, size and number were not affected by mealybug feeding. In conclusion, grapevine response to P. ficus is gradual and involves different plant parts depending on the severity of the attack. Contrary to previous assumptions, this study demonstrates considerable direct impacts of mealybug feeding on temporal and perennial parts of grapevine plants.

Emergency response for evaluating SARS-CoV-2 immune status, seroprevalence and convalescent plasma in Argentina

Emergency response for evaluating SARS-CoV-2 immune status, seroprevalence and convalescent plasma in Argentina Ojeda, Diego Sebastian; González López Ledesma, María Mora; Pallarés, Horacio Martín; Costa Navarro, Guadalupe Soledad; Sanchez, Lautaro Nicolas; Perazzi, Beatriz Elizabeth; Villordo, Sergio; Alvarez, Diego Ezequiel; Echavarría, Marcela Silvia; Oguntuyo, Kasopefoluwa Y.; Stevens, Christian S.; Lee, Benhur; Carradori, Jorge; Caramelo, Julio Javier; Yanovsky, Marcelo Javier; Gamarnik, Andrea Vanesa We report the emergency development and application of a robust serologic test to evaluate acute and convalescent antibody responses to SARS-CoV-2 in Argentina. The assays, COVIDAR IgG and IgM, which were produced and provided for free to health authorities, private and public health institutions and nursing homes, use a combination of a trimer stabilized spike protein and the receptor binding domain (RBD) in a single enzyme-linked immunosorbent assay (ELISA) plate. Over half million tests have already been distributed to detect and quantify antibodies for multiple purposes, including assessment of immune responses in hospitalized patients and large seroprevalence studies in neighborhoods, slums and health care workers, which resulted in a powerful tool for asymptomatic detection and policy making in the country. Analysis of antibody levels and longitudinal studies of symptomatic and asymptomatic SARS-CoV-2 infections in over one thousand patient samples provided insightful information about IgM and IgG seroconversion time and kinetics, and IgM waning profiles. At least 35% of patients showed seroconversion within 7 days, and 95% within 45 days of symptoms onset, with simultaneous or close sequential IgM and IgG detection. Longitudinal studies of asymptomatic cases showed a wide range of antibody responses with median levels below those observed in symptomatic patients. Regarding convalescent plasma applications, a protocol was standardized for the assessment of end point IgG antibody titers with COVIDAR with more than 500 plasma donors. The protocol showed a positive correlation with neutralizing antibody titers, and was used for clinical trials and therapies across the country. Using this protocol, about 80% of convalescent donor plasmas were potentially suitable for therapies. Here, we demonstrate the importance of providing a robust and specific serologic assay for generating new information about antibody kinetics in infected individuals and mitigation policies to cope with pandemic needs.

8-Hydroxyquinoline platinum(ii) loaded nanostructured lipid carriers: synthesis, physicochemical characterization and evaluation of antitumor activity

8-Hydroxyquinoline platinum(ii) loaded nanostructured lipid carriers: synthesis, physicochemical characterization and evaluation of antitumor activity Boztepe, Tugce; Scioli Montoto, Sebastián; Ruiz, María Esperanza; Alvarez, Valeria Alejandra; Castro, Guillermo Raul; Leon, Ignacio Esteban Every year the incidence of cancer and the death rate are increasing worldwide. The drug 8-hydroxyquinoline platinum(II) [PtCl(8-O-quinoline)(dmso)] (8HQ-Pt) has been identified as a promising antitumor complex. Nanostructured lipid carriers (NLC) are second-generation drug nanocarrier systems that have superior advantages over other kinds of colloidal carrier systems. 8HQ-Pt compound loaded NLC formulations of cetyl esters (SS) were synthesized via ultrasonication in the presence of two different liquid oils: capric triglyceride, or olive oil. The physicochemical and microscopic characterizations of NLC were analyzed via dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction analysis (XRD). In vitro drug release and cytotoxicity, cell uptake and apoptosis assays against the human colon cancer cell line HT-29 were investigated. The results showed that NLCs indicated a narrow size distribution and a mean particle diameter in the range of 136?159 nm. The thermal characteristic analysis confirmed the stability of NLCs up to 185 °C. Encapsulation efficiencies of the 8HQ-Pt compound in NLCs were about 80% and the 8HQ-Pt compound in the formulations showed a controlled release profile during 72 h. The release profiles of these two different formulations and the antitumor effect on the HT-29 cell line were compared with those of the free 8HQ-Pt compound. The cellular uptake of two different NLC groups was proved by fluorescence microscopy and the presence of capric triglyceride liquid oil in the formulation increased the intracellular drug delivery capacity when compared with olive oil.

Native, exotic, and livestock prey: assessment of puma Puma concolor diet in South American temperate region

Native, exotic, and livestock prey: assessment of puma Puma concolor diet in South American temperate region Guerisoli, Maria de Las Mercedes; Gallo, Orlando; Martínez, Sabrina Daniela; Luengos Vidal, Estela Maris; Lucherini, Mauro Understanding the food habits of mammalian carnivores is crucial for the comprehension of the role of apex-predators in maintaining healthy ecosystems. The puma is currently the most widespread top predator and the carnivore most frequently involved in conflicts with humans in the Americas. We analyzed puma diet in the South American temperate region, a vast area largely modified by humans, to assess the importance of native prey with respect to livestock and exotic species. We reviewed 18 studies published between 1991 and 2020 to which we added 19 feces of puma from a rangeland area of central Argentina. “Undetermined small rodent,” plains vizcacha, European hare, and wild boar were the most frequent species in the small area of the Argentinean Espinal. In the southern temperate region, exotic (European hare and wild boar) and native species (guanaco and armadillos) were the most frequent wild prey species, while sheep was the most frequent livestock followed by cattle. Exotic species had a greater frequency of occurrence than native and livestock species. Livestock frequency of occurrence was greater inside protected areas than outside. These findings reveal that, although the puma is considered in this large area as conflictive, wild prey (exotic and native) are its main food sources. Given the potentially crucial role exotic species can play in the ecosystem, understanding the role of pumas in controlling their populations is a challenge for future research.

Selective microstructure-size filters for non-invasive quantitative imaging by mag- netic resonance

Selective microstructure-size filters for non-invasive quantitative imaging by mag- netic resonance Zwick, Analía Elizabeth; Capiglioni, Milena Sofía; Jiménez, Pablo Javier; Alvarez, Gonzalo Agustin Extracting quantitative microstructure information of living tissue by non-invasive imaging is an outstandingchallenge for understanding disease mechanisms and allowing early stage diagnosis of pathologies. Magnetic Reso-nance Imaging (MRI) is a promising and widely used technique to pursue this goal, but still provides low resolutionto reveal microstructure details [1]. We here report on a method to produce images of filtered microstructure-sizesbased on selective probing of nuclear-spin dephasing induced by the molecular diffusion within specific tissue-compartments [2]. The microstructure-size filter relies on suitable dynamical control of nuclear spins that sensemagnetization decay-shifts rather than the commonly used spin-echo decay-rates. The feasibility and performanceof the method are illustrated with proof-of-principle experiments and simulations on typical size-distributions ofwhite-matter in the mouse brain [3]. These results show that spin-echo decay-shifts can be a new MRI paradigmto advance towards unravelling diagnostic information based on microstructure parameters that characterize bio-logical tissues.

Ritualidades para la tierra: "Memorias envueltas del habitar"

Ritualidades para la tierra: "Memorias envueltas del habitar" Martinez, Maria Soledad; Cohen, Maria Lorena Presentaremos distintos atados, paquetes y envoltorios vinculados al mundo ritual andino, los mismos fueron elaborados en tiempos históricos y enterrados y/0 depositados en lugares habitados desde los albores del segundo milenio de la era y reutilizados en contextos colonial y republicano. Hablamos de una práctica, que involucra distintas temporalidades, materializada en estos objetos amarrados, no sólo entre ellos sino también a espacios habitados por ancestras y ancestros. El primero de los hallazgos, corresponde a un q'uepi o conjunto enmarañado de fragmentos de piezas -mayormente textiles- hallado en la cumbre de Peñas Coloradas, el segundo, a un envoltorio o paquete de cuero de llama con la misma procedencia que el anterior, y el último, a un atado procedente de un recinto residencial de Punta de la Peña 3, sector C. Ambos sitios ubicados en el curso medio e inferior sobre la margen sur del río Las Pitas, en Antofagasta de la Sierra, puna de Catamarcа. El sitio Peñas Coloradas 3 cumbre, se interpretó como una cima baja en la que se conformó en un espacio predominantemente ritual, vinculado al culto de los ancestros que protegían al entorno habitado, ampliamente visibilizado desde allí. Se identificaron unas 20 unidades arquitectónicas de función residencial y funeraria construidas en tiempos previos al contacto hispano, pero reutilizadas posteriormente. Las cámaras actuaron tanto para alojar a los cuerpos humanos sin vida como también para almacenar elementos variados (alimentos, herramientas, materias primas). En tiempos republicanos, se enterraron en el interior de las cámaras, otro tipo de objetos los cuales identificamos como a) q’uepi, y b) un envoltorio o paquete de cuero de llama, que guarecía un fragmento textil de sarga azul en su interior. En tanto, Punta de la Peña 3 sector C, corresponde a unidad doméstica, con una configuración arquitectónica dada por una agrupación de recintos habitacionales, un patio rectangular y recintos productivos. En el interior de una habitación residencial (del complejo A), en proximidad a un fogón, se halló en el interior de un pozo, un atado constituido por un conjunto de textiles (industriales y artesanales), cordeles, vellones, semillas de algarrobo, plumas, restos de leñosas y un cordel trenzado. Este atado, compuesto por ítems entrelazados, se encontró envuelto en un cuero de oveja, cuyo interior resguardaba también un fragmento de tela industrial con una costura artesanal de unión (que remite a una modalidad textil local propia) de mediados y fines del Siglo XIX. Podemos concluir que la construcción y entierro de estos envoltorios o paquetes y, q'uepi forman parte de las ritualidades para la tierra. La vuelta de estos elementos a la matriz que les dio origen debió ser parte de una práctica que los amarraba al territorio conformado por lugares con memorias profundas. Así se lograba conectar gente, tiempos, historias de vida, lazos parentales y el sentido ancestral de los espacios, aportando a la renovación de ciclos del habitar andino y la reproducción de identidad territorial.

Seguridad Alimentaria: (Escala global, 1974-2000)

Seguridad Alimentaria: (Escala global, 1974-2000) González, José Fernando Concepto que define las condiciones mínimas para satisfacer las necesidades alimentarias. Acuñado por los organismos internacionales dedicados a la agricultura y la alimentación a mediados de la década de 1970, adquirió diferentes significados hasta integrar en sus principales dimensiones la disponibilidad, el acceso (físico, social y económico), la utilización y la estabilidad de los alimentos.

Proyecto Arqueológico Infiernillo: 8000 años de historia en la Quebrada de Los Corrales, Tucumán

Proyecto Arqueológico Infiernillo: 8000 años de historia en la Quebrada de Los Corrales, Tucumán Oliszewski, Nurit; Martinez, Javier Gustavo; Arreguez, Guillermo Anibal; Backwell, Lucinda Ruth; Coronel, Alexis Alberto; Di Lullo, Eugenia; Funes Coronel, Jorge Alejandro; Gramajo Bühler, María Cecilia; Mercuri, Cecilia; Molar, R.; Montegu, J.; Naharro, E.; Nasif, Norma; Vera, Yanet Desde 2005 investigamos la arqueología de la Quebrada de Los Corrales (QDLC), ubicada por encima de los 3000 msnm en el Abra de El infiernillo, en el oeste de la provincia de Tucumán. La aplicación de un enfoque integral que entrecruza distintas líneas metodológicas y teóricas ha permitido generar un amplio corpus de conocimiento que se sintetiza a continuación.El área de estudio tiene una superficie total aproximada de 28 km² y comprende a la cuenca inferior, media y superior del río de Los Corrales. En la cuenca inferior se encuentra Cueva de Los Corrales 1, una cueva de uso intermitente entre 3000 y 650 AP. En la cuenca media/superior se registran extensas áreas con estructuras agrícolas y pastoriles. En el curso superior se ubica la localidad arqueológica de Puesto Viejo donde se concentran al menos 47 unidades residenciales que conformaron un gran núcleo aldeano durante el primer milenio d.C. Hacia el sur de PV se encuentra el sitio Taller Puesto Viejo 1 (TPV1) que tiene la particularidad de contar con una larga persistencia ocupacional (7800-1750 AP). QDLC es una de las pocas áreas del NOA en donde se registra una continuidad en las ocupaciones humanas desde el Holoceno medio al tardío, lo cual incluye el proceso generalizado de transición desde una economía basada en caza y recolección hacia un esquema de producción agro-pastoril.Las ocupaciones más antiguas datan de 7800 AP con la presencia de grupos cazadores recolectores móviles. Luego hacia 3800 AP tuvo lugar un proceso transicional hacia la producción de alimentos evidenciado principalmente por una base residencial ubicada en TPV1. En dicha base se llevaron a cabo múltiples actividades como molienda, manufactura y uso de vasijas cerámicas, elaboración y uso de artefactos líticos, consumo de guanacos producto de la caza e inhumaciones mediante prácticas crematorias con acompañamiento de artefactos como cuentas de collar y semillas de quínoa y maíz. Todo esto nos permitió proponer la ocurrencia de un proceso local que llevó a grupos cazadores-recolectores móviles a arraigarse y paulatinamente constituirse en una aldea agro-pastoril sedentaria.La ocupación más intensa se dio durante los primeros siglos de la Era Cristiana (1840-1560 AP) materializada en un conjunto aldeano ubicado en Puesto Viejo, asociado a extensas áreas productivas compuestas por aproximadamente 450 hectáreas cubiertas por andenes y corrales. Es así que, durante 350 años, en QDLC funcionó una aldea autosuficiente orientada a la producción de alimentos. Hacia 1550 AP las ocupaciones humanas en esta zona se vieron interrumpidas por el probable acontecimiento de un evento volcánico que habría inutilizado la producción agrícola y el agua para consumo humano y animal. A partir de ese momento y especialmente durante el segundo milenio d.C., QDLC habría funcionado sólo como un espacio de circulación sin ocupación/producción efectiva.Toda esta información, generada a lo largo de muchos años de trabajo, estará a disposición de la sociedad en el Centro de Interpretación El Infiernillo ubicado en la entrada de la Quebrada de Los Corrales sobre RP 307.

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