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Acceso Abierto Villa Gesell: un desequilibrio sedimentario inducido por fijaciones de médanos(Asociación Argentina de Sedimentología, 1998) Isla, Federico; Bértola, Germán R.; Farenga, Marcelo; Serra, Susana; Cortizo, Luis CamiloVilla Gesell fue construida sobre una barrera de médanos transversales a los vientos del SO. La fijación de estas dunas (plantaciones y forestaciones) alteró la morfología original y la dinámica eólica, principalmente a partir de una disminución de la disponibilidad de arena que transformó, en ciertos sectores, los médanos transversales en parabólicos. Parte de la arena litoral fue a colmatar las depresiones intermedanosas dispuestas perpendicularmente a la línea de costa. A partir de fotografías aéreas se constató que en el centro de Villa Gesell la línea de ribera no ha retrocedido significativamente en 24 años. Sólo hacia el sur del partido, se reconoce la erosión litoral debido indirectamente a la fijación de la barrera que produjo médanos frontales ( foredunes ) subalimentados. A través de balances sedimentarios de cinco playas se reconocieron zonas de diferente dinámica. Las playas del norte poseen intercambios volumétricos significativamente menores que los del sur. Las arenas gruesas se deben a procesos de retrabajamiento de depósitos litorales fósiles del sur. El transporte eólico selectivo, desde la playa hacia la barrera (inducido por las forestaciones), es también causante de que en la playa dominen las granulometrías gruesas. - Comunicacion
Acceso Abierto Observaciones sobre la producción y conservación de cebolla en el sudeste de Buenos Aires en relación con la disponibilidad hídrica(2007) Assuero, Silvia Graciela; Rattin, Jorge; Saluzzo, José; Sasso, Gastón; Tognetti, Jorge AlbertoEn experimentos con siete cultivares de cebolla de diferente longitud de ciclo, realizados en el sudeste de la provincia de Buenos Aires (Argentina) bajo restricción hídrica, se observó además del esperable tamaño reducido de los bulbos, una llamativa desmejora en su conservación, en relación con ensayos sin limitaciones de agua. La marcada aceleración de la brotación y el incremento en la tasa de pérdida de peso de los bulbos en almacenamiento como consecuencia de las restricciones hídricas durante el llenado fueron confirmadas en un ensayo independiente con el cv. Valcatorce INTA. Estos resultados sugieren la necesidad de replantear el manejo del agua en cebolla al menos cuando se pretende su conservación a largo plazo, como es el caso de los cultivos para exportación. - Artículo
Acceso Abierto Comparación de dos sistemas modernos de conducción de cerezo (Prunus avium) en base a la eficiencia de intercepción lumínica(2007) Godoy, Carlos; Tognetti, Jorge AlbertoLos sistemas de conducción modernos de cerezos son diseñados para maximizar la intercepción lumínica y optimizar su distribución en el canopeo, y de esta manera incrementar la productividad y mejorar la calidad de los frutos. Se evaluaron dos sistemas: Eje Central (EC) con moderadamente alta densidad de plantación y Tatura Modificado (TM) con muy alta densidad, en términos de intercepción de energía lumínica y distribución del área foliar en el canopeo, en una plantación comercial durante dos temporadas consecutivas. El perfil de intercepción de TM puso en evidencia una mayor iluminación en el centro de la doble fila con respecto a EC en el centro de la fila. La intercepción a nivel del suelo fue de 21 % en EC y de 38 % en TM, habiéndose determinado un índice de área foliar (IAF) para EC de 2,02 y de 3,89 para TM. La eficiencia en la penetración de la luz en el canopeo fue mayor en TM que en EC. Al evaluar el diámetro basal de las ramas laterales, los árboles conducidos en TM resultaron más equilibrados. - Artículo
Acceso Abierto Bacillus subtilis as a bioindicator to estimate pentachlorophenol toxicity and concentration(2009) Ayude, M. A.; Okada, E.; González, J. F.; Haure, P. M.; Murialdo, Silvia ElenaPentachlorophenol (PCP) and its sodium salt (Na-PCP) are extremely toxic chemicals responsible for important soil and groundwater pollution, mainly caused by wastes from wood-treatment plants, because chlorinated phenols are widely used as wood preservatives. The methods most commonly used for routine analysis of pesticides such as PCP and Na-PCP are high-performance liquid chromatography (HPLC) and gas chromatography– mass spectroscopy (GC–MS). A variety of rapid biological screening tests using marine organisms, bioluminescent bacteria, and enzymes have also been reported. In this study, rapid biological screening analysis using Bacillus subtilis was developed, to assess the biodegradation of PCP and its by-products in liquid samples. An empirical model is proposed for spectrophotometric analysis of Na-PCP concentration after growth of Bacillus subtilis. - Artículo
Acceso Abierto Analysis Of Bacterial Chemotactic Response Using Dynamic Laser Speckle(2009) Murialdo, Silvia Elena; Sendra, Gonzalo Hernán; Passoni, Lucía I.; Arizaga, Ricardo; Gonzalez, Jorge Froilan; Rabal, Héctor J.; Trivi, Marcelo RicardoChemotaxis has a meaningful role in several fields, such as microbial physiology, medicine and biotechnology. We present a new application of dynamic laser speckle or biospeckle to detect different degrees of bacterial motility during chemotactic response experiments. Encouraging results showed different bacterial dynamic responses due to differences in the hardness of the support in the swarming plates. We compare this method to a conventional technique that uses white light. Both methods showed to be analogous and, in some cases, complementary. The results suggest that biospeckle processed images can be used as an alternative method to evaluate bacterial chemotactic response and can supply additional information about the bacterial motility in different areas of the swarm plate assay that might be useful for biological analysis. - Documento de conferencia
Acceso Abierto Apoplastic hydrophobic proteins involved in tuber defense response to P. Infestans(2009) Fernández, M.B; Daleo, Gustavo Raúl; Guevara, M.G.; Pagano, M.R.During infection, oomycetes secrete effectors into the plant apoplast where they interact with host resistance proteins. In response, large amounts of protease and protease inhibitors (PIs), are accumulated. We analyzed differentially expressed Apoplastic Hydrophobic Proteins (AHPs) in potato tubers from Innovator (resistant) and Spunta (susceptible) cvs, after wounding and P. infestans infection. Intercellular washing fluid was extracted from control, wounded or infected tubers at 0, 24 and 48 h and chromatographed into a PepRPCtmHR5/5 in FPLC. After elution with acetonitrile, fractions were analyzed by SDS-PAGE and proteins identified by MALDITOF- MS. Innovator cv. showed a higher basal AHP content and hydrophobicity than Spunta cv. In the latter, infection induced accumulation of patatins and PIs, whereas in Innovator cv. no changes in PIs accumulation were observed. In response to P. infestans infection, lypoxigenase, enolase, annexin p34 and glutarredoxin/cyclophilin were accumulated in both cvs. Hydrophobicity of AHPs was higher after 24 h of wounding and infection in both cultivars. These results suggest that an increase in AHPs concentration would be related with the protection against the oomycete and with the degree of resistance to pathogens. Finally, changes in hydrophobicity of Pis may induce changes in proteaseinhibitor interaction affecting the defense response. - Documento de conferencia
Acceso Abierto Analysing the expression of genes associated with induced resistance in potato plants treated with phosphites(2009) Machinandiarena, M.F.; Feldman, M.; Daleo, Gustavo Raúl; Andreu, A.B.Phosphites (Phi) have the ability to protect plants against different pathogens, both through a direct effect in oomycete metabolism and by an indirect effect stimulating the plant´s natural defence responses. We have previously shown that KPhi foliar application to potato plants resulted in different protection levels against Phytophthora infestans depending on dose and plant age at application time. In order to identify genes that are involved in induced resistant in plants treated with KPhi, we analyzed by RT PCR, the time course of transcript levels of two genes which encode predicted transcription factors involved in pathogen perception and defence gene expression. Preliminary results showed that WRKY and NPR1 were differentially induced in plants both treated with Phi and infected with Phytophthora infestans, showing an earlier and highest induction than infected plants non treated with Phi. These results may allow us to hypothetize that Phi treatment might trigger a fast mechanism to protect potato plants to pathogen infections. - Documento de conferencia
Acceso Abierto Differentially expressed genes in potato sprouts after potassium phosphite application(2009) Feldman, M.; Machinandiarena, M.F.; Amarilla, L.D.; Guzzo, M.C.; Di Rienzo, J.; Daleo, Gustavo Raúl; Andreu, A.B.We are studying the role of phosphites in disease control management, yield and potato tuber quality. In brief, our previous results showed a number of promising properties associated with these compounds. When we applied potassium phosphites (KPhi) at 3 litre $latex ha^{-1} $ to seed tubers immediately after cutting, this promoted early emergence, an increased in stem number and diameter, early tuber initiation and an increased in the number of tubers per plant. In addition to these physiological effects, phosphite treatment also resulted in greater resistance in seed tubers to Phytophthora infestans, Fusarium solani and Rhizoctonia solani. In order to understand the mechanisms which regulate these responses, we analyzed the changes in gene expression in tubers seeds at early stage of sprouting after KPhi treatment. Preliminary results of microarray analysis from potato sprouts treated or not with KPhi, showed that 26 genes were upregulated in the treated ones. These genes were classified into 5 groups: plant defense, metabolism, abiotic stress, transcription factors and unknown genes. We performed semiquantitative RT-PCR assays of some of these genes to validate the results. Interestingly one of these genes was CULLIN 1, involved in jasmonic acid mediated signaling pathway. This result may support the hypothesis that phophites could be involved in triggering IR (induced resistant). - Artículo
Acceso Abierto Psychophysical estimation of acid intensity and determination of sweet-acid interaction in a fish paste containing glycerol(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2010) Sanchez Pascua, Gabriela Leonor; Casales, María Rosa; Yeannes, María IsabelIn a fish paste made with cooked Brazilian flathead (Percophis brasiliensis), glycerol (17%), sodium chloride (1.5%) and potassium sorbate (0.1%) the following acid percentages: 0.2; 0.4; 0.6; 0.8, 1 and 1.5% w/w were incorporated to determine the relationship between added acetic acid and the sensorially perceived intensity, and the effects of the combination of sweet-acid tastes. Tests for paired comparison, ranking and structured verbal scales for sweet and acid attributes and psychophysical test were carried out. There was a perceptible difference among samples for differences of 0.4 units of acid concentration. Samples indicated as sweeter by 89.47% of the judges were those containing a lesser acid concentration. A reduction in glycerol sweetness when increasing acid levels was observed. Acetic acid reduced the sweetness of glycerol and inversely glycerol reduced the acidity of acetic acid. The data obtained with the magnitude estimation test agree with Steven’s law. - Artículo
Acceso Abierto Functional Cytology of the Hepatopancreas of Palaemonetes argentinus (Crustacea, Decapoda, Caridea) Under Osmotic Stress(Instituto de Tecnologia do Paraná - Tecpar, 2010) Díaz, Ana Cristina; Sousa, Liliana Graciela; Petriella, Ana MaríaThe present work describes the effect of different salinities on the functional morphology of the P. argentinus hepatopancreas and analyses the tissue recovery after re-acclimation to freshwater. Adult prawns of both sexes at sexual rest were collected from a tributary of the Mar Chiquita coastal lagoon. The prawns were acclimated in aquaria to four salinity conditions: 0 (control), 8, 16 and 24‰. To evaluate the possible tissular recovery, after 60 days individuals from all the treatments were gradually acclimated to freshwater and maintained for other 30 days. Hepatopancreas samples were processed at the beginning of the trial and every 30 days using standard histological techniques for OM and TEM. The individuals from all the treatments, except the controls, showed a continuous weight decrease, and survival was lower when higher the salinity. At 30 days from the beginning of the experiment, hepatopancreas from 16 and 24‰ salinities showed an enlarged tubular lumen and an infolded basal lamina. Ultratructurally, nuclear retraction, cytoplasmolysis, and RER membranes separated with electron-dense content were observed in all the treatments except 0‰. After 60 days, profound alterations were observed with the three treatments. After the re-acclimation period, there was no reestablishment of the functional cytology. The tolerance to short-term salinity changes explains the capability of this prawn to inhabit in estuarine environments. - Artículo
Acceso Abierto Multisubstrate Monod Kinetic Model for Simultaneous Degradation of Chlorophenol Mixtures(2011) Durruty, Ignacio; Okada, Elena; González, Jorge Froilan; Murialdo, Silvia ElenaChlorophenols (CPs) are persistent and highly toxic compounds rated as priority pollutants by the Environmental Protection Agency (EPA). Frequently, these compounds are present as mixtures of CPs in industrial wastewaters. Therefore the study of biodegradation on mixed pollutants is an important aspect of biodegradation and wastewater treatment. In this work, we studied the multisubstrate degradation of CPs by a mixed culture of Pseudomonas aeruginosa and a novel Acromobacter sp. capable of using pentachlorophenol (PCP), 2,4,6 trichlorophenol (2,4,6 TCP) and 2,3,5,6 tetrachlorophenol (2,3,5,6 TeCP) as the sole sources of carbon and energy. The main objective of this work was to evaluate the effect of substrate mixtures on the degradation kinetics of PCP. Batch experiments were conducted with each CP separately and in mixtures of PCP + 2,4,6 TCP, PCP + 2,3,5,6 TeCP, and PCP + 2,4,6 TCP + 2,3,5,6 TeCP. Based upon our results we have concluded that the simultaneous degradation of CPs is a key factor contributing to the improvement of PCP degradation. The kinetic parameters for PCP and 2,4,6 TCP were obtained by fitting the data to a Monod kinetics model. Using such parameters, the model was able to predict simultaneous multisubstrate degradation of PCP with others CPs. - Artículo
Acceso Abierto Effect of foliar applications of phosphite on post-harvest potato tubers(2011) Lobato, M.C.; Maschinandiarena, M.F.; Tambascio, C.; Dossio G.G.A.; Caldiz, D.; Daleo, Gustavo Raúl; Andreu, A.B; Olivieri, F.P.The utilization of phosphites (Phi) could be considered as another strategy to be included in integrated disease management programmes to reduce the intensive use of fungicides and production costs. The aim of the present work was to analyze whether the beneficial effects of phosphite treatment previously observed in potato plants grown under greenhouse conditions, were reflected after harvest of field grown potatoes, both in disease protection and in yield. In addition, biochemical compounds possibly involved in induced defence responses by Phi, like phytoalexins, pathogenesis related proteins and oxidative stress enzymes were measured. Foliar applications of KPhi to field grown crops resulted in post-harvest tubers with a reduced susceptibility to Phytophthora infestans, Fusarium solani and Erwinia carotovora infections, suggesting that this compound induced a systemic defence response. An increase in phytoalexin content in P. infestans inoculated tubers obtained from Phi-treated plants suggests their participation in the defence response. Chitinase content increased 72h after wounding or inoculation with P. infestans in tubers from KPhi-treated plants compared to wounded or infected tubers from non-treated plants. Contrary to this, the isoforms of β-1,3-glucanases analyzed did not increase in the tubers of Phi-treated plants. The increment in peroxidase and polyphenol oxidase activities indicated that these enzymes could be part of the Phi defence mechanism. No negative effects were observed in potato yield at harvest, measured as total tuber weight and dry matter, after foliar KPhi treatment. This suggests that the energetic cost involved in the defence response activation would not be detrimental to plant growth. - Artículo
Acceso Abierto Cholesterol and membrane phospholipid compositions modulate the leakage capacity of the swaposin domain from a potato aspartic protease (StAPs-PSI).(2011) Muñoz, F.F; Palomares-Jerez, M.F.; Daleo, Gustavo Raúl; Villalaín, J.; Guevara, M.GPotato aspartic proteases (StAPs) and their swaposin domain (StAsp-PSI) are proteins with cytotoxic activity which involves plasma membrane destabilization. The ability of these proteins to produce cell death varies with the cellular type. Therefore, StAPs and StAsp-PSI selective cytotoxicity could be attributed to the different membrane lipid compositions of target cells. In this work we investigate the possible mechanism by which StAPs and StAsp-PSI produce selective membrane destabilization. Results obtained from leakage assays show that StAsp-PSI is a potent inducer of the leakage of LUVs containing anionic phospholipids, especially those containing phosphatidylglycerol. Based in these results, we suggest that the cytotoxic activity of StAsp-PSI on pathogenic microorganisms could be mediated by the attraction between the exposed positive domains of StAsp-PSI and the negatively charged microorganism membrane. On the other hand, our circular dichroism spectroscopic measurements and analysis by size exclusion chromatography and followed by electrophoresis, indicate that hydrophobic environment is necessary to StAsp-PSI oligomerization and both StAsp-PSI disulfide bounds and membrane with negative charged phospholipids are required by StAsp-PSI to produce membrane destabilization and then induce cell death in tumors and microorganism cell targets. Additionally, we demonstrate that the presence of cholesterol into the LUV membranes strongly diminishes the capacity of StAsp-PSI to produce leakage - Artículo
Acceso Abierto Achromobacter marplatensis sp. nov., isolated from a pentachlorophenol contaminated soil(Microbiology Society, 2011) Gomila, Margarita; Tvrzová, Ludmila; Teshim, Andrea; Sedláek, Ivo; González Escalona, Narjol; Zdráhal, Zbynk; Šedo, Ondrej; González, Jorge Froilán; Bennasar, Antonio; Moore, Edward R. B.; Lalucat, Jorge; Murialdo, Silvia ElenaA polyphasic taxonomic approach was applied to the study of a Gram-negative bacterium (B2T) isolated from soil by selective enrichment with pentachlorophenol. 16S rRNA gene sequence analysis of strain B2T showed that the strain belongs to the genus Achromobacter within the Betaproteobacteria. The 16S rRNA gene sequence displayed more than 99 % similarity to the sequences of the type strains of all species of Achromobacter, with the highest sequence similarity to those of Achromobacter spanius CCM 7183T and A. piechaudii CCM 2986T (99.8 %). On the basis of phylogenetic analysis, genomic DNA–DNA relatedness and phenotypic characteristics, including chemotaxonomic (cellular fatty acid profile) analysis, a novel species is proposed, Achromobacter marplatensis sp. nov., with the type strain B2T ( = CCM 7608T = CCUG 56371T = CECT 7342T). - Artículo
Acceso Abierto Degradation of chlorophenol mixtures in a fed-batch system by two soil bacteria(Water Research Commission, 2011) Durruty, Ignacio; Okada, Elena; González, Jorge Froilán; Murialdo, Silvia ElenaThis work was undertaken to investígate the effect of variations of the feed rate on a fed-batch set-up used to degrade xenobiotics. The mixture of substrates was composed of PCP, 2,4,6 TCP and 2,3,5,6 TeCP (pentachlorophenol, 2,4,6 trichlo- rophenol and 2,3,5,6 tetrachlorophenol respectively). Two acclimated bacteria isolated from soil were used: Pseudomonas aeruginosa and Achromobacter sp. nov. The different flow rates tested were: I: 0.5 ml*min-1, II: 1.67 ml*min$latex ^{} $-1 and III: 2.00 mf-min'1. Our results show that during fed-batch operation the 2,4,6 TCP exhibits an earlier degradation than the other com- pounds, for all of the flow rates tested. This indicates that in this case the degradation of the most recalcitrant compounds (PCP and 2,3,5,6 TeCP) is benefited by the increase in biomass ofbacteria, due to the metabolisation of a less recalcitrant compound (2,4,6 TCP). The defined parameter, specific degradation rate (SDR), was demonstrated to be very useful for comparing the degradation abilities at different flow rates of a fed-batch system. The degradation efficiencies were shown to be higher than 90% for all of the cases and to decrease as the feed rate increases. However, the SDR, a parameter that involves the rate of degradation and the biomass, increases as the flow rate increases. At a feed flow rate of 2 mf-min'1 SDR reaches a maximum of 12.476 x 10'10 mgCP-M-CFU'1. Finally, among the feed flows tested, taking into account both the degradation efficiency and the SDR, 2 ml-min-1 is the most convenient flow rate for chlorophenol degradation in fed-batch Systems. An even higher degradation efficiency (97%) can be achieved by using the feed rate of 2 mf-min'1 followed by an additional batch post-treatment of2 h, with a SDR of 13.136 x 10-10 mg CP-h1-CFU1. - Artículo
Acceso Abierto Effect of salinity changes on the midgut gland of Artemesia longinaris (Decapoda, Penaeidae)(Universidad Católica de Valparaíso, 2012) Masson, Ignacio; Díaz, Ana Cristina; Petriella, Ana M.The response of the midgut gland of Artemesia longinaris to salinity changes was evaluated by analyzing its histological changes. Animals were exposed gradually and abruptly to 33, 29, 25 and 16 psu for different time intervals and readapted to 33 psu for 30 days. Individuals maintained 10 days at 16 psu showed the lowest survival and presented histopathologies which were not present in those readapted to 33 psu. Shrimps abruptly transferred from 33 to 16 psu died in 3-5 h but did not show midgut gland alterations likely due to the brief exposure. Only shrimps abruptly transferred from 33 to 25 psu presented histopathologies after 96 h. When readapted to 33 psu for 30 days, the midgut gland recovered an unaltered structure. Except E-cells, which did not vary in height among treatments, F, R and B-cells were taller in animals gradually adapted to 29 than to 16 psu. Abrupt salinity changes had a significant effect on the mean height of F, R and B-cells of those animals transferred from 33 to 25 psu (from 24 to 96 h after transfer F and R-cells heights decreased, and from 96 to 144 h after transfer B-cells height increased). Our study shows the effect of osmotic stress at the tissue level on the midgut gland and, at least partially, explains the reason for the mortalities at low salinities. - Artículo
Acceso Abierto Potassium phosphite primes defense responses in potato against(2012) Machinandiarena, M.F.; Lobato, M.C.; Feldman, M.; Daleo, Gustavo Raúl; Andreu, A.B.Although phosphite is widely used to protect plants from pathogenic oomycetes on a wide range of horticultural crops, the molecular mechanisms behind phosphite induced resistance are poorly understood. The aim of this work was to assess the effects of potassium phosphite (KPhi) on potato plant defense responses to infection with Phytophtora infestans (Pi). Pathogen development was severely restricted and there was also an important decrease in lesion size in infected KPhi-treated leaves. We demonstrated that KPhi primed hydrogen peroxide and superoxide anion production in potato leaves at 12 h post-inoculation with Pi. Moreover, the KPhi-treated leaves showed an increased and earlier callose deposition as compared with water-treated plants, beginning 48 h after inoculation. In contrast, callose deposition was not detected in water-treated leaves until 72 h after inoculation. In addition, we carried out RNA gel blot analysis of genes implicated in the responses mediated by salicylic (SA) and jasmonic acid (JA). To this end, we examined the temporal expression pattern of StNPR1 and StWRKY1, two transcription factors related to SA pathway, and StPR1 and StIPII, marker genes related to SA and JA pathways, respectively. The expression of StNPR1 and StWRKY1 was enhanced in response to KPhi treatment. In contrast, StIPII was down regulated in both KPhi- and water-treated leaves, until 48 h after infection with Pi, suggesting that the regulation of this gene could be independent of the KPhi treatment. Our results indicate that KPhi primes the plant for an earlier and more intense response to infection and that SA would mediate this response. - Artículo
Acceso Abierto Molecular modifications in tuber periderm and cortex associated to pathogen resistance induced by phosphite treatment(2012) Olivieri, F.P.; Feldman, M.; Machinandiarena, M.F.; Lobato, M.C.; Caldiz, D.; Daleo, Gustavo Raúl; Andreu, A.B.Phosphite (Phi) compounds are salts derived from phosphorous acid. These compounds have the ability to protect plants against different pathogens. The aim of the present research was to assess the effect of Phi compounds on components of potato tuber periderm and cortex and to assess their effects on pathogen resistance in the postharvest stage. In a series of field experiments, potassium phosphite (KPhi) was applied to seed potato tubers and foliage. After harvest, several variables were analyzed in tubers obtained from these plants. An increase in pectin content was observed in both periderm and cortex tissue in tubers originating from KPhi-treated plants. After wounding and infection with Fusarium solani, a higher amount of pectin accumulation in cortical tissues was observed in tubers following treatment with KPhi. The content and/or activity of polygalacturonase and proteinase inhibitor also increased in tubers from KPhi-treated plants. A new isoform of chitinase was detected in the tuber periderm of treated plants. These results suggest that KPhi applied to seed tuber and foliage induces defense responses in tuber periderm and cortex and that these reactions are associated with structural and biochemical changes in these tissues. - Artículo
Acceso Abierto DEVDase activity is induced in potato leaves during Phytophthora infestans infection.(2012) Fernández, M.B.; Daleo, Gustavo Raúl; Guevara, M.G.Programmed cell death (PCD) occurs in plants, animals and several branches of unicellular eukaryotes as a part of developmental and/or defense processes. Caspase proteases are universal mediators of animal apoptosis, a type of PCD. In plants, there are not animal caspase homologs; therefore, the characterization of caspase-like activities is of considerable importance to our understanding of PCD in plants. Here we report for the first time the involvement of caspase-3-like activity in the resistance mechanism of potato to Phytophthora infestans infection. We showed that disease development in infected potato leaves is dependent of caspase-3-like activity. Unlike plant DEVDases previously reported, this DEVDase activity was sensitive to the serine protease inhibitor PMSF. As reported for other subtilisin- like proteases with caspase activity, potato DEVDase activity was mainly localized in the apoplast. We demonstrated that in total protein extract DEVDase activity accounts for a 60% of serine prot - Documento de conferencia
Acceso Abierto El hábitat en la 3ra edad: análisis y diagnóstico de tipologías de viviendas en altura de zonas centrales de la Ciudad de Mar del Plata en función de los requerimientos de los adultos mayores(2013) Fernandez, JenniferEl propósito de este trabajo es avanzar con la evaluación objetivable de Viviendas en Altura de la Zona Céntrica de la Ciudad de Mar del Plata (VAZC) en función de los requerimientos de los Adulto Mayores (AM). Se plantea una metodología desde un enfoque cuanti-cualitativo, utilizando estudios de tipo exploratorio-descriptivos, mediante el estudio de casos. Durante el año 2012 se realizaron 10 observaciones directas de AM que habitan VAZC que resultaron en el registro de relatos exhaustivos sobre el uso de los espacios de la vivienda, relevamiento fotográfico y la confección de planos en planta de cada una con su equipamiento y distribución. A partir de esto se ha avanzado en la elaboración una grilla, para la comparación y procesamiento de datos, que permita extraer generalizaciones para un análisis y diagnóstico cuantitativo de VAZC, aplicable a un amplio espectro tipológico extraído de los archivos municipales de edificios de vivienda. Si bien los trabajos permitieron recabar datos sobre distintos aspectos de este campo habitacional (incluidos espacios de uso común y usos de la planta baja), nos remitiremos aquí a aquellos aspectos referidos a los espacios privativos de las unidades de vivienda.